Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Molecular Dynamics of Yukawa System (Dust Plasma) with Deformable Periodic Boundary Conditions: Formulation7587ENHirooTotsujiYoshihikoInoueTokunariKishimotoChiekoTotsujiShigetoshiNara10.18926/15381Molecular dynamics of the Yukawa system, the system of particles interacting via the Yukawa or the screened Coulomb potential, are formulated for various statistical ensembles and external conditions. The Yukawa potential smoothly interpolates the long-range Coulomb and the short-range interactions by adjusting a single parameter, the
screening length. In order to reduce the effect of boundaries, the periodic boundary conditions are imposed and the deformations of the fundamental vectors of periodicity are taken into account. Ewald-type expressions for interaction energy, force, and kinematic pressure are
given explicitly.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Intrinsic Bistability of Coupled Quantum Wires: Localization due to Many-Body Effects5564ENHirooTotsujiShigetoshiNara10.18926/15394The ground state of a system of electrons accumulated in a pair of coupled symmetric quantum wires is analyzed on the basis of density functional theory. It is shown that, in a domain of physical parameters, electrons are localized in either of wires. The main contribution to the total energy of this system comes from the Hartree energy, or the electrostatic energy, and the exchange-correlation energy between electrons. The ground state is determined by a competition between these contributions: We have symmetric electron distributions when the Hartree energy dominates and asymmetric (localized) states are realized in the opposite case. This kind of simple system with bistable electronic states may be applied to semiconductor memory devices.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Electronic States and Electron Wave Transfer in Coupled Quantum Wires and Its Control by Externally Applied Electric Field6579ENShigetoshiNaraHirooTotsuji10.18926/15395Quantum mechnical electron wave transfer between two quantum wires which are weakly coupled via a thin potential barrier is considered. The total electronic states are calculated with both analytical ( no field case ) and numerical methods ( under applied electric fields ). The transfer efficiency is evaluated for several specified cases of geometrical structures, potential barrier heights and the externally applied electric field. Estimated trasfer time is of the order of one picosecond in typical mesoscopic structures. The model in this paper can be used to determine important structure parameters for experiments on electron directional coupler controled by external elctric field.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712721993Complex Dynamics and Search in A Cycle-Memory Neural Network1940ENShigetoshiNaraHirooTotsuji10.18926/15403Numerical simulations of a single layer recurrent neural network model in which the synaptic connection matrix is formed by summing cyclic products of succesive patterns show that complex dynamics can occur with the reduction of a connectivity parameter which is the number of connection between neurons. The structure in these dynamics is discussed from the viewpoint of realizing complex function using complex dynamics.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Molecular Dynamics ofa Coulomb System with Deformable Periodic Boundary Conditions5159ENHirooTotsujiShigetoshiNara10.18926/15418Variable shape molecular dynamics is formulated for the one-component plasma and the structural transition from the fcc lattice to the bcc lattice has been observed. It is emphasized that the condition of constant volume should be imposed when deformations of periodic boundary conditions are taken into account.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712811993A Simple Method to Evaluate Structural Stability of Group IV and III-V Semiconductors125ENShigetoshiNaraHirooTotsuji10.18926/15432The structural stabilities of bulk Si, Ge, and GaAs are discussed based on the total energy evaluated by the summation of the band structure energy and the short-range repulsive potential between ions. The band structure energy
is calculated by means of the simple tight-binding method. The tight-binding parameters are determined so as to fit to the results of a pseude potential calculation and Harrison's model is employed to include the influence of lattice deformation. The short-range-force is assumed to be of the exponential form and parameters are determined so as to reproduce an experimental value of bulk modulus. This treatment qualitatively well describes structural properties in spite of the simple computational procedure and roughly gives the known variation of the total energy for a <100> uniaxial strain. This method is able to be applied to an investigation of the structural stabilities of superlattices, for example, a strained layer superlattice consisting of hetero-semiconductors.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712811993Ground State of Coupled Quantum Wires2738ENHirooTotsujiShigetoshiNara10.18926/15434The ground states of interacting electrons in coupled quantum wires are analyzed on the basis of the density functional theory. The exchange-correlation potential is calculated from 'exact' results given by the Green's function Monte Carlo method in two and three dimensions. It is shown that the critical density signifying the change from symmetrical to asymmetrical ground state is weakly dependent on the details of the exchange-correlation potential. These critical values are compared with the result of the three-dimensional analysis for a single wire.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Memory Search using Genetic Algorithms and a Neural Network Model111128ENShigetoshiNara10.18926/15443An information processing task which generates combinatorial explosion and program complexity when it is treated by a serial algorithm is investigated using both Genetic Algorithms (GA) and a neural network model (NN). The task in question is to find a target memory from a set of stored entries in the form of "attractors" in a high dimensional state space. The representation of entries in the memory is distributed ("an auto associative neural network" in this paper), and the problem is to find an attractor under a given access information where the uniqueness or even existence of a solution is not always guaranteed ( an ill-posed problem ). The GA is used as an algorithm for generating a search orbit to search effectively for a state which satisfies the access condition and belongs to the target attractor basin in state space. The NN is used to retrieve the corresponding entry from the network. The results of our computer simulation indicate that the present method is superior to a search method which uses random walk in state space. Our technique may prove useful in the realization of flexible and adaptive information processing, since pattern search in high dimensional state spaces is common in various kinds of parallel information processing.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712821994Numerical Simulation of Quantum Systems -Dynamics of Electrons in Microstructures-4552ENHirooTotsujiSeijiHashimotoShigetoshiNara10.18926/15460Difficulties in simulating systems composed of classical and quantum particles lie in the treatment of the many-body interactions between quantum particles and the geometrical variety of configurations of classical particles. In order to overcome these difficulties, we have developed some numerical methods and applied them to simple cases. As for stationary states, the finite element method provides us with sufficient geometrical freedom.
Combined with the Kohn-Sham equation based on the density
functional theory, this method virtually satisfies our requirement. In order to investigate time-dependent phenomena, we apply the time-dependent Kohn-Sham equation. Adopting the finite difference method, we are able to follow the development of quantum many-body system. As an example, we estimate the effects of the potential height, the electric field, and many-body interactions in some transition processes in quantum wells coupled by a tunneling barrier. This example is important in itself in relation to semiconductor superlattices and also serves as a benchmark for quantum simulations, variety of geometry
corresponding to that of classical particles.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712911994Electronic States in Semiconductor Quantum Dot with Fluctuating Interfaces714ENHirooTotsujiShigetoshiNaraChiekoTotsuji10.18926/20011Effects of interface fluctuations on the electronic states in semiconductor quantum dots are analyzed on the basis of numerical solutions for ground state wave functions and
energy eigenvalues. It is shown that the effective volume of confinement becomes smaller than the real volume of quantum dots due to fluctuation. This effect comes from the
fact that the wave functions with larger characteristic wavelength are not able to deform themselves following the fluctuation of interfaces exactly.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713311998Measurement of saturated solubilities and diffusion coefficients of pure gases to mineral oil1930ENSeiichiWashioSatoshiTakahashiChikashiImotoAtsumasaYoshida10.18926/19608The present paper deals with measurements of the diffusion coefficients as well as the saturated solubilities of single component gases such as N(2), O(2) and CO(2) to a mineral oil. The method to determine the diffusivity is based upon measuring the pressure changes caused by the one-dimensional diffusion between the gas and the oil enclosed in an airtight container. For N(2) and O(2) the profiles of the measured pressure changes agree well with those predicted by diffusion theory, whereas that is not the case with CO(2). Although the reason why CO(2) does not seem to obey diffusion theory has yet to be studied, it may suggest the possibility that the diffusion coefficient varies with the pressure, considering that the range of pressure change in the diffusivity measurement was much obtained by this method fell within }30% around the average. Moreover the solubility measurements have made clear that Henry's law holds true between the three pure gases and the oils tested, and that O(2) and CO(2) dissolve into the oil approximately two and ten times more, respectively, than N(2).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Structure, Morphology and Color Tone Properties of theNeodymium Substituted Hematite9398ENMakotoNakanishiTatsuoFujiiJunTakada10.18926/14088Co-precipitation method has been employed to fabricate neodymium substituted hematite with different compositions from the aqueous solution of their corresponding
metal salts. Thermal analysis and X-ray diffraction studies revealed the coexistence of Fe(2)O(3) and Nd(2)O(3) phases up to 1050Ž and formation of solid solution phase among
them at 1100Ž and above temperatures, which was evidenced by shifting of the XRD peaks. Unit cell parameters and the cell volumes of the samples were found to increase by adding Nd(3+) ions in the reaction process. FESEM studies showed the suppression of particle growth due to the presence of Nd(3+) ions. Spectroscopic measurement evidenced that neodymium substituted hematite exhibited brighter yellowish red color tone than that of pure ƒ¿-Fe(2)O(3).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Preparation and Characterization of Ti(2)O(3) Films Deposited on Sapphire Substrate by Activated Reactive Evaporation Method6975ENTatsuoFujiiTokuroNanbaAkiyoshiOsakaYoshinariMiuraJunTakada10.18926/15436(001)-oriented Ti(2)O(3) films were epitaxially grown on a(001)-face of sapphire single-crystalline substrate by an activated reactive evaporation method. The formation ranges of stoichiometric and nonstoichiometric Ti(2)O(3) films were determined as a function of the substrate temperature (Ts), the oxygen pressure (Po(2)) and the deposition rate. Stoichiometric Ti(2)O(3) films were grown at Ts†673K under Po(2)†1.0~10(-4)Torr, which showed the metal-insulator transition with a sharp change in electrical resistivity from 3.5~10(-2) to 2.6~10(-3)ƒ¶cm at 361K. Nonstoichiometric films prepared under less oxidized conditions did not exhibit the transition. The nonstoichiometry of the Ti(2)O(3)films was discussed in terms of excess Ti ions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Structural Analysis of Minimum Weight Codewords of the (32, 21, 6) and (64, 45, 8) Extended BCH Codes Using Invariance Property19ENTakuyaKoumoto10.18926/14053Two typical examples, the (32, 21, 6) and (64, 45, 8) extended code of primitive permuted BCH codes, are considered. The sets of minimum weight codewords are analyzed in terms of Boolean polynomial representation. They are classied by using their split weight structure with respect to the left and right half trellis sections, and for each class, the standard form is presented. Based on the results, we can generate a proper list of the minimum weight codewords of the codes.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Geometric BIC1017ENKenichiKanatani10.18926/14055The author introduced the "geometric AIC" and the "geometric MDL" as model selection criteria for geometric fitting problems. These correspond to Akaikefs "AIC" and Rissanen's "BIC", respectively, well known in the statistical estimation framework. Another criterion well
known is Schwarzf "BIC", but its counterpart for geometric fitting has been unknown. This paper introduces the corresponding criterion, which we call the "geometric BIC", and shows that it is of the same form as the geometric MDL. We present the underlying logical reasoning of Bayesian estimation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Fundamental Matrix Computation: Theory and Practice1835ENKenichiKanatani10.18926/14056We classify and review existing algorithms for computing the fundamental matrix from point correspondences and propose new effective schemes: 7-parameter Levenberg-Marquardt (LM) search, EFNS, and EFNS-based bundle adjustment. Doing experimental comparison, we show that EFNS and the 7-parameter LM search exhibit the best performance and that additional bundle adjustment does not increase the accuracy to any noticeable degree.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Fast Exponentiation in Extension Field with Frobenius Mappings3643ENHidehiroKatoKentaNekadoYasuyukiNogamiYoshitakaMorikawa10.18926/14057This paper proposes an exponentiation method with Frobenius mappings. Our method is closely related to so-called interleaving exponentiation. Different from the interleaving exponentiation methods, our method can carry out several exponentiations using same base at the same time. The efficiency to use Frobenius mappings for an exponentiation in extension field is well introduced by Avanzi and Mihailescu. This exponentiation method is based on so-called simultaneous exponentiation and uses many Frobenius mappings. Their method more decreased the number of multiplications; however, the number of Frobenius mappings inversely increased. Compared to their method , the number of multiplications needed for the proposed method becomes about 20% larger; however, that of Frobenius mappings becomes small enough.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Vibrational Properties of Si Crystal with Vacancy : A Tight-Binding Study4447ENKenjiTsurutaChiekoTotsujiHirooTotsuji10.18926/14058To analyze vibrational properties of Si crystal with a single charge-neutral vacancy, we perform large-scale simulations based on tight-binding molecular-dynamics method.
Vibrational modes and frequencies are obtained by diagonalizing dynamical matrix within a harmonic approximation. Results indicate that there exist vibrational modes spatially localized around the vacancy and large frequency shifts associated with the localized
modes contribute significantly to reduction of the vibrational free energy.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Numerical Simulations of Two-dimensional Electron Fluid : An Application of Classical-map Hypernetted-chain Method4852ENChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14059Based on the mapping introduced by the classical-map hypernetted-chain (CHNC) method, classical
numerical simulations, Monte Carlo and molecular dynamics, have been applied to the twodimensional
electron fluid and the results are compared with those of quantum Monte Carlo simulations
hitherto reported. It is shown that polarization properties of the ground state obtained by the diffusion Monte Carlo method are reproduced within the accuracy of quantum simulations by both of two mapping functions for the quantum temperature which have been proposed within the
CHNC method. These results may serve as the basis of numerical simulations based on the CHNC method which are applicable to finite non-periodic systems like quantum dots and systems at finite temperatures.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Transfer of Quantum Information by Spin Chains : Effect of Noise5355ENHirooTotsuji10.18926/14060In order to transfer quantum information, the use of spin chains has been proposed and their transfer characteristics have been analyzed. As one of the latter, the maximum of the transfer probability over sufficiently long time period is often considered important and some examples with high maximum values have been given. In these examples, the coupling between neighboring spins are tuned so as to attain high efficiency. In this article, we discuss the effect of noise on the values of coupling constant. As a result, we propose a system where the efficiency is high and also the effect of noise is small.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Spin Polarization of Two-Dimensional Electron System in a Finite Domain5659ENChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14061We analyze the ground state of the two-dimensional quantum system of electrons confined in a parabolic potential with the system size around 100. We map the system onto a classical system on the basis of the classical-map hypernetted-chain (CHNC) method which has been proven to work in the integral-equation-based analyses of uniform unbounded systems and then apply classical numerical simulations. We find that the confined system undergoes the transition to the spin polarized state with the decrease of the average density and the corresponding critical value is as low as rs ∼ 0.3 in terms of the usual rs parameter estimated for the average density. As the ground state
for given value of the rs parameter, our data give the critical value for the transition around 20 which
is consistent with the known possibility. The advantage of our method is a direct applicability to geometrically complex systems which are difficult to analyze by integral equations. The application to the structure like quantum dots reported here is the first example of such applications.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Transfer Planning of Molten Metals in Steel Worksby Decentralized Agent6070ENJunjiKikuchiMasamiKonishiJunImai10.18926/14062In steel works, molten metals discharged from blast furnace are put into a pan for transportation called torpedo and transported to steel making factory by a locomotive. In molten metals transportation, it becomes issues to prevent temperature drop of molten metals for stable production of down stream plants to shorten transportation time. Therefore it is necessary to make an appropriate plan for molten metals transfer considering the production
and the transportation simultaneously. In this paper, molten metals transfer planning method is proposed including production scheduling. That is, torpedo schedule, transfer request assignment and route plan of locomotives are optimized according to each objective.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Optimization of Inventories for Multiple Companies by Fuzzy Control Method7178ENKoichiKawaseMasamiKonishiJunImai10.18926/14063In this research, Fuzzy control theory is applied to the inventory control of the supply chain between multiple companies. The proposed control method deals with the amount
of inventories expressing supply chain between multiple companies. Referring past demand and tardiness, inventory amounts of raw materials are determined by Fuzzy inference. The method that an appropriate inventory control becomes possible optimizing fuzzy control gain by using SA method for Fuzzy control. The variation of uncertain demand is given to the proposal method. Furthermore, the method of forecasting demand and the effectiveness of fuzzy control method are confirmed by numerical experiments. As the results, the proposal method suppressed increase in an unnecessary cost when demand varies.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Temperature Distribution Control of Reactor Furnace by StateSpace Method using FEM Modeling7990ENMasamiKonishiJunImai10.18926/14064The operations of a reactor furnace such as a blast furnace still depend on the experiences and intuitions of skilled operators due to the complexity of internal furnace phenomena and high temperature. There is a great demand for stable operations under the circumstances of a decrease in the number of skilled operators and difficulty in technology inheritance.
This paper aims to construct mathematical description for control of a reactor furnace.
Further, the linear-quadratic-gaussian control system for a reactor furnace is proposed, which estimates inner furnace temperature distribution using measured data near furnace wall.
Temperature distribution of a furnace is controlled based on the estimated inner temperature distribution changing of boundary conditions of a furnace. The practicability of the proposed control method was checked through numerical experiments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Cooperation of Production, Product Handling and TransferScheduling for Semiconductor Fabrication91103ENHamanaRyoheiMasamiKonishiJunImai10.18926/14065Various kind of productions are made in semiconductor fabrications, where it employs the production system with multiprocesses and multiple Automated Guided Vehicles(AGVs)
for transportation. It is difficult to optimize planning of production and transportation simultaneously
because of the complicated flow of semifinished products. This paper describes the formulations of production scheduling, transportation routing and sequence planning of
material handling system, and algorithm for simultaneous optimization of plannings by using solution space reduction and simulated annealing method. In this paper, all production system is decomposed to the production scheduling problem, transportation routing problem
by AGVs and sequence planning of material handling system with managing stockers and buffers. Production scheduling problem and transportation routing problem are solved
by the optimization algorithm using the decomposition routing problem. Sequence planning of material handling robot problem is solved by the algorithm using simulated annealing method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Fatigue Crack Propagation Evaluated by Electric Resistance and Ultrasonics in Copper Film Bonded to Base Metal with Resin104109ENMADonghuiTashiyukiToriiKenichiShimizuAkiraMatsuba10.18926/14069As model specimens of surface film-bonded materials, pure copper films with a thickness of 100ƒÊm were bonded to the surface of steel base with epoxy resin, where the tensile residual stress was measured by an X-ray on the surface copper film. The distribution of initial electric resistance was measured on both copper film and base specimen by a direct current potential drop technique. As a result, there was a good agreement between the measured and theoretical values. From the fatigue testing results, it was shown that the measured electric resistance increased with the fatigue crack length on the copper film, which was almost equal to the theoretical value calculated for a central slit in a plate with finite width. This was probably because the fatigue crack was opened due to the tensile residual stress on the film even under unloading condition. In addition, the internal crack length during fatigue was examined by ultrasonic testing for the film-bonded specimen. As a result, there was a difference in the fatigue crack length between the surface copper film and the inner base.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008A Method for Checking the Parity of (#Jc - 1)=2 of Genus 2 and 3 Hyperelliptic Curves110114ENYasuyukiNogamiYoshitakaMorikawa10.18926/14071This paper shows a method for checking the parity of (#Jc | 1)/2 without calculating the order #Jc, where #Jc is the order of genus 2 or 3 hyperelliptic curve.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007The Number of the Irreducible Cubic Polynomials in the Form of x(3) + ax + b with a Certain Fixed Element a110ENYasuyukiNogamiYoshitakaMorikawa10.18926/14079In this paper, we first show the number of x's such that x(2) +u, u ¸ F(*)(p) , becomes a quadratic residue in F(p), and then this number is proven to be equal to (p+1)/2 if |u is a quadratic residue in Fp, which is a necessary fact for the following. With respect to the irreducible cubic polynomials over Fp in the form of x(3)+ax+b, we give a classification based on the trace of an element in F(p3) and based on whether or not the coefficient of x, i.e. the parameter a, is a quadratic residue in Fp. According
to this classification, we can know the minimal set of the irreducible cubic polynomials, from which all the irreducible cubic polynomials can be generated by using the following two variable transformations: x=x + i, x=j|1x, i, j ¸ Fp, j ‚ 0. Based on the classification and that necessary fact, we show the number of the irreducible cubic polynomials in the form of x(3)+ax+b, b ¸ F(p), where a is a certain fixed element in F(p).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007An Algorithm for Generating Irreducible Cubic Trinomials over Prime Field1119ENYasuyukiNogamiYoshitakaMorikawa10.18926/14080This paper proposes an algorithm for generating irreducible cubic trinomials in the form x(3) + ax + b, b ¸ F(p), where a is a certain fixed non-zero element in the
prime field F(p). The proposed algorithm needs a certain irreducible cubic trinomial over F(p) to be previously given as a generator; however, the proposed algorithm can generate irreducible cubic polynomials one after another by changing a certain parameter in F(p). In this paper, we compare the calculation cost and the average computation time for generating an irreducible cubic polynomial, especially trinomial, among Hiramoto et al. irreducibility testing algorithm, Berlekamp-Massey minimal polynomial determining algorithm, and the proposed algorithm. From
the experimental results, it is shown that the proposed algorithm is the fastest among the three algorithms for generating irreducible cubic trinomials.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Method for Production Planning and Inventory Control in OilRenery2030ENTakujiImamuraMasamiKonishiJunImai10.18926/14081In this paper, we propose a simultaneous optimization method for inventory control and production planning problem for a chemical batch plant. The plant consists of
blending process, intermediate storage tanks and filling process. In the proposed method, the original problem is decomposed into production planning sub-problem and inventory control sub-problem. Then the decision variables are optimized by alternately solving each sub-problem. The solution of the proposed method is compared with that of centralized optimization method. The effectiveness of the proposed method is investigated from numerical
computational results.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Simultaneous Optimization of Production and TransportationPlanning by using Logic Cut Algorithm3143ENRyoheiHamanaMasamiKonishiJunImai10.18926/14082Various kind of productions are made in semiconductor factories, where it employs the production system with
multiprocess and multiple Automated Guided Vehicles(AGVs) for transportation. It is difficult to optimize
planning of production and transportation simultaneously because of the complicated flow of semifinished products.
This paper describes the formulations of production scheduling and transportation routing, and algorithm
for simultaneous optimization of plannings by using logic cuts. The entire problem is decomposed to the master
problem and the sub problem. If it derives the infeasible solutions, new constraints are added to the master
problem to eliminate the solution area including infeasible solutions. The results of about optimality and computation
time by using CPLEX solver are shown compared with conventional decomposition method to check
up effectivity of proposed method in small size problem, and about optimality and computaion time for large
scale problem.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Decomposition of Time Petri Nets for Solving Optimal FiringSequence Problem4451ENRyotaMaenoMasamiKonishiJunImai10.18926/14083Petri net model is a frequently-used versatile tool which can represent a widely discrete event system. However, when the scale of the system becomes large, the calculation time for solving optimal problem (optimal firing sequence problem) is markedly increased. In this paper, we propose an approximation method that achieves the efficiency improvement of the solution by decomposing the Petri net for solving the optimal firing sequence problem.
A timed Petri Net is decomposed into several subnets in which the optimal firing sequence for each subnet is solved by Dijkstrafs algorithm in polynomial computational complexity.
The effectivity of the proposed method is verified by numerical experiments for the flowshop schedule problem.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Heat and Mass Transfer Analysis of Fluidized Bed Grain Drying5262ENHideoInabaAkihikoHoribeNaotoHaruki10.18926/14084The effects of heat and mass transfer parameters on the efficiency of fluidized bed drying have been studied to optimize the input and output conditions. The analysis was carried out using two different materials, wheat and corn. Energy and exergy models based on the first and second
law of thermodynamic are developed. Furthermore, some unified non-dimensional experimental correlations for predicting the efficiency of fluidized bed drying process have been proposed. The effects of hydrodynamics and thermodynamics conditions such as the inlet air temperature, the initial moisture content and well known Fourier and Reynolds numbers on energy efficiency and exergy
efficiency were analyzed using the developed model. A good agreement was achieved between the model predictions, non-dimensional correlations and the available experimental results.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Experimental Evaluation of Geometric Fitting Algorithms6372ENKenichiKanataniYasuyukiSugaya10.18926/14086The convergence performance of typical numerical schemes for geometric fitting for computer vision applications is compared. First, the problem and the associated KCR lower bound are stated. Then, three well known fitting algorithms are described: FNS, HEIV, and renormalization.
To these, we add a special variant of Gauss-Newton iterations. For initialization of iterations, random choice, least squares, and Taubinfs method are tested. Numerical simulations and real image experiments and conducted for fundamental matrix computation and ellipse
fitting, which reveals different characteristics of each method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714112007Statistical Optimization for Geometric Fitting: TheoreticalAccuracy Bound and High Order Error Analysis7392ENKenichiKanatani10.18926/14087A rigorous accuracy analysis is given to various techniques for estimating parameters of geometric models from noisy data for computer vision applications. First, it is pointed out that parameter estimation for vision applications is very different in nature from traditional statistical analysis and hence a different mathematical framework is necessary in such a domain. After general theories on estimation and accuracy are given, typical existing techniques are selected, and their accuracy is evaluated up to higher order terms. This leads to a ghyperaccurateh method that outperforms existing methods.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Fatigue Crack Propagation Behavior Bent from Precrack under Mixed-Mode Conditions - Noting the Crack-Surface Contact due to a Compressive Residual Stress along a Precrack -18ENYouLiMaKenichiShimizuTashiyukiTorii10.18926/14096A testing for bent fatigue crack propagation under mixed-mode conditions was carried out using fatigue and annealed slant precracks with different slant angles, ƒÀ ,defined as the angle between loading and precrack directions in a rectangular plate. As a result, bent fatigue crack from the fatigue precrack with ƒÀ =45deg. propagated under mixed-mode conditions with mode II stress intensity factor (K(II))(est) evaluated from the discontinuous displacement measured along the crack. On the other hand, bent fatigue crack from the fatigue precrack with ƒÀ =60deg. and from the annealed precracks with both slant angles of ƒÀ =60deg. and ƒÀ =45deg. propagated under the mode I behavior. This was because the compressive residual stress near the fatigue precrack caused contact to each other between the upper and the lower surfaces of the precrack with the smaller slant angle ƒÀ . Furthermore, the fatigue crack propagation rates indicated almost the same relationship for all the data, using the mixed-mode effective stress intensity factor (K(M))(est), calculated from the discontinuous displacement measured along the bent fatigue crack.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Statistical Estimation Model for Product Quality of Petroleum915ENTakashiNukinaMasamiKonishiTatsushiNishiJunImai10.18926/14097Controls of the temperature, pressure and flowing quantity are important for the stable operation of the product quality in the distillation tower. The usual measuring way of product quality estimation is made by the off-line analysis. In this paper, online estimation method of product quality is studied for improving the product quality. The estimation method based on stochastic analysis was developed for online estimation. In this paper, the
data of temperature, pressure and flow volum in the distillation tower are treated.
As the estimation models, RNN (Recurrent Neural Net Work) and PLS (Partial Least Square Regression Method) were adopted. The actual plant data were used in the analysis.
Both PLS and RNN models could compensate each other to improve the accuracy in estimation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006RNN Based Auto-tuning of PID Control Gains in Hot StripLooper Controller1622ENYoshihiroAbeMasamiKonishiTatsushiNishiJunImai10.18926/14098In this study, auto tuning of PID control gains in hot strip looper controller is made based on RNN model. Neuro emulator is employed to model the characteristics of looper
dynamics. Combining neuro emulator and RNN model, auto tuning system of PID control gains is constructed. As the inputs to RNN, plural evaluation functions which reflect individual preference of human experts. Further, Self learning mechamism is embeded to RNN model which enables adaptation to the change in rolling chracteristics. Through numerical experiments, the effect of the proposed method is ascertained.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Transfer Routing of Ore Yard by Decentralized Agent Method2330ENJunjiKikuchiMasamiKonishiTatsushiNishiJunImai10.18926/14099In steel works, iron ores are stored in ore yard and sent to various plants of down stream accoding to transfer requests. To attain stable operation, it is neccesary to keep a certain allowable stock level in ore tanks of all plants. To this purpose, ore transfer routing method has been developed based on decentralized agent method. In case of disaster such as a big earthquake or a big fire, damages in the facilities of industrial complex may be unavoidable. In this paper, decentralized optimization method is tested to cope with such emergencies. Decentralized agents corresponding to kind of ore make their own transfer
route plan exchanging information with others. As the application of the proposed method, transfer scheduling in ore yard in steel works are made in case of destruction of transfer facilities.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Melting of Spherical Yukawa Clusters Analyzed by Monte CarloSimulation3135ENTakafumiOgawaChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14119We analyze the melting of spherical Yukawa clusters by Monte Carlo simulations. Spherical clusters are expected to be found in dusty plasmas in an isotropic environment such as microgravity and serve as a model for classical clusters. We obtain the specific heat through fluctuations of the potential energy and identify its peak as the transition temperature. Melting temperatures are compared with those of bulk Yukawa systems and it is confirmed that the melting temperature increases and approaches the bulk value with the increase of the system size.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Stochastic-Dierence-Equation Method for Long Time-scaleMolecular Dynamics Simulations3639ENAtsushiUchidaChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14120We present a Stochastic-Difference-Equation (SDE) approach to long time-scale molecular dynamics (MD) simulations, which are required for nanosecond-scale phenomena. In this method, the MD trajectory in a fixed time period is obtained as a stationary solution of an action functional
based on an error accumulation of the equation of motion along the path, thus reducing the problem to a boundary-value problem, instead of an initial-value problem in the ordinary MD method. We apply the method to formation processes of Cu thin film via nanocluster deposition onto a substrate.
The applicability of the SDE algorithm to the problem and the effects of the choice of SDE parameters on the optimization processes of configuration pathway are examined.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Distribution of Electrons in Quantum Dots Analyzed by Classical Mapping and Molecular Dynamics4043ENMiyakeTakashiChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14121The electron system of arbitrary degeneracy can be mapped onto a classical system where electrons of the same spin are assigned an additional interaction and the effect of degeneracy is taken into account through an imaginative temperature. We apply this method to electrons in quantum dots modeled as two-dimensional electron liquid confined in a finite domain by a harmonic potential. We analyze distribution functions by molecular dynamics instead of solving integral equations which are not so useful in the case without translational invariance.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Generating Dense Point Matches Using Epipolar Geometry4452ENYasuyukiSugayaKenichiKanataniYasushiKanazawa10.18926/14122Dense point matches are generated over two images by rectifying the two images to align epipolar lines horizontally, and horizontally sliding a template. To overcome inherent limitations of 2-D search, we incorporate the gnaturalness of the 3-D shapeh implied by the resulting matches.
After stating our rectification procedure, we introduce our multi-scale template matching scheme and our outlier removal technique using tentatively reconstructed 3-D shapes. Doing real image experiments, we discuss the performance of our method and remaining issues.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Uncalibrated Factorization Using a Variable Symmetric Affine Camera5363ENKenichiKanataniYasuyukiSugaya10.18926/14123In order to reconstruct 3-D Euclidean shape by the Tomasi-Kanade factorization, one needs to specify an affine camera model such as orthographic, weak perspective, and paraperspective. We present a new method that does not require any such specific models. We show that a minimal requirement for an affine camera to mimic perspective projection leads to a unique camera model, which we call a symmetric affine camera, which has two free functions. We determine their values from input images by linear computation and demonstrate by experiments that an
appropriate camera model is automatically selected.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Overview of 3-D Reconstruction from Images6477ENKenichiKanatani10.18926/14124This article summarizes recent advancements of the theories and techniques for 3-D reconstruction
from multiple images. We start with the description of the camera imaging geometry as
perspective projection in terms of homogeneous coordinates and the definition of the intrinsic and extrinsic parameters of the camera. Next, we described the epipolar geometry for two, three, and four cameras, introducing such concepts as the fundamental matrix, epipolars, epipoles, the trifocal tensor, and the quadrifocal tensor. Then, we present the self-calibration technique based on the stratified reconstruction approach, using the absolute dual quadric constraint. Finally, we give the definition of the affine camera model and a procedure for 3-D reconstruction based on it.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006The Orders of Elliptic Curves y(2) = x(3) + b, b ¸ F(* q)8394ENYasuyukiNogamiYoshitakaMorikawa10.18926/14126This paper particularly deals with elliptic curves in the form of E(x, y) = y(2) | x(3) |b = 0, b ¸ F(* q) , where 3 divides q|1. In this paper, we refer to the well-known twist technique as x-twist and propose y-twist. By combining x-twist and y-twist, we can consider six elliptic curves and this paper proposes a method to obtain the orders of these six curves by counting only one order among the six curves.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Application of Neural Network to Fault Diagnosis ofElectro-Mechanical System2127ENTakashiTorigoeMasamiKonishiJunImaiTatsushiNishi10.18926/14146In this paper, neuro based intelligent diagnosis methods for electro-mechanical control
system are proposed. A self organizing map neural network (SOM) is used to classify
measured data of the target system as a qualitative diagnostic method. Besides of the above
procedure, it is expected to attain more efficient maintenance by a quantitative estimation
of failure. For the purpose, new method is proposed using a hierarchical neural network
(HNN). In the method, classified results by SOM are processed for the quantitative diagnosis.
Hierarchical neural network can identify inner structure of the relations between failure
causes and its results that enables a quantitative diagnosis.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Application of Sequential Quadratic Programming Method toTemperature Distribution Control in Reactor Furnace2839ENKazuhitoIshimaruMasamiKonishiJunImaiTatsushiNishi10.18926/14148In reactor furnace, due to high temperature and high pressure, data can be measured only near the furnace wall. In this paper, the way to estimate temperature distribution in a reactor furnace using measured data near the furnace walls and to control temperature distribution to the desired temperature distribution was studied. In the estimation, SQP method is employed using measured data near the furnace walls. As the result, the whole temperature distribution in a furnace could be obtained from such limited data. Furthermore, to control the temperature distribution in a reactor furnace, gas flow from multiple tuyeres and supplying material for controlling temperature distribution in a reactor furnace were determined by the SQP method. It was shown that temperature distribution in a furnace was regulated to achieve various desired distribution. Thus, it was verified that complicated temperature distribution in a reactor furnace could be controlled by combining furnace simulation and SQP method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Agent Based Plant Allocation and Transfer Routing of Productsin Case of Emergency4045ENSulaimanAl-SehaimMasamiKonishiKazuoNose10.18926/14149In this paper, two problems, plant allocation problem and that of transfer routing from plants to customers, are considered simultaneously. Especially, adaptation scheme for emergency cases are checked. To solve these problems, decentralized agent based optimization procedures are used. In our study, oil production and products transfer in Saudi Arabia are treated. Through numerical experiments, practicability of the proposed method is verified.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Electron Dynamics in Semiconducting Nanowires: A Real-Space,Polynomial-Expansion Approach4651ENKeisukeKadonoChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14150We present a real-space, polynomial-expansion approach to electron dynamics in nanostructured semiconductors. The Chebyshev expansion method is employed for efficient calculation of timeevolution of single-electron wave function. Details of the formulation are described. The method is applied to the electron transport in nanostructured semiconductors such as Si nanowires. The
mean-square displacement and diffusivity of electron in Si chains are obtained as functions of length of the chains. The results show clearly ballistic behavior of electron in the pure Si chain.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Large-Scale Molecular Dynamics Simulation of CoulombClusters: A Finite-Temperature Analysis5255ENKatsuyaKanamoriChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/14152Thermal behavior of Coulomb clusters in a three dimensional confining potential is investigated by molecular dynamics simulations for system sizes of 1,000 to 20,288 ions. The specific heat of the system of shell-structured 20,000 ions is peaked almost at the same temperature as the system of
bcc-structured 20,288 ions with much sharper structure for the latter. The diffusion coefficient and the peak to valley ratio of the two-dimensional pair distribution function on the outermost shell are obtained both as a function of temperature. The rotational movement of each shell in the system
of 104 ions is observed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Extracting Moving Objects from a Moving Camera VideoSequence5662ENYasuyukiSugayaKenichiKanatani10.18926/14153We present a new method for extracting objects moving independently of the background from a video sequence taken by a moving camera. We first extract and track feature points through the sequence and select the trajectories of background points by exploiting geometric constraints
based on the affine camera model. Then, we generate a panoramic image of the background and compare it with the individual frames. We describe our image processing and thresholding techniques.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Optimality of Maximum Likelihood Estimation for GeometricFitting and the KCR Lower Bound6370ENKenichiKanatani10.18926/14155Geometric fitting is one of the most fundamental problems of computer vision. In [8], the author derived a theoretical accuracy bound (KCR lower bound) for geometric fitting in general and proved that maximum likelihood (ML) estimation is statistically optimal. Recently, Chernov and Lesort [3] proved a similar result, using a weaker assumption. In this paper, we compare their formulation with the authorfs and describe the background of the problem. We also review recent topics including semiparametric models and discuss remaining issues.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Immobilization of Photoelectric Dye on the Polyethylene FilmSurface1620ENTetsuyaUchidaSanaeIshimaruKaoruShimamuraAkihitoUjiToshihikoMatsuoHiroshiOhtsuki10.18926/14136PE film was treated with fuming nitric acid at 80Ž for 20 min, resulting in introduction of COOH moieties on the film surface. The COOHfs were reacted with ethylenediamine,
whose amino groups were used for linking with (2-[4-(dibutylamino)phenyl]ethenyl)-3-carboxy-methylbenzo-thiazolium, photoelectric dye (NK-5962), which absorbs visible light and converts the photon energy to electric potentials. The dye molecules were immobilized
on the PE film surface and they were able to stimulate chick retinal tissues on incidence of visible light. These facts hopefully lead to development of an artificial retinal prosthesis.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005A Method for Generating Prime Order Elliptic Curves over F(q(2c))7181ENYasuyukiNogamiYoshitakaMorikawa10.18926/14156This paper proposes an algorithm for generating prime order elliptic curves over extension field whose extension degree is a power of 2. The proposed algorithm is based on the fact that the order of the twisted elliptic curve is able to be a prime number when the extension degree for the twist operation is a power of 2. When the definition field is F(2(40)|87)(4) , the proposed algorithm can generate a prime order elliptic curve within 5 seconds on PentiumIII (800MHz) with C language.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005A High-Speed Square Root Computation in Finite Fields with Application to Elliptic Curve Cryptosystem8292ENFengWangYasuyukiNogamiYoshitakaMorikawa10.18926/14157In this paper, we focus on developing a high-speed square root (SQRT) algorithm required for an elliptic curve cryptosystem. Examining Smart algorithm, the previously well-known SQRT algorithm, we can see that there is a lot of computation overlap in Smart algorithm and the quadratic residue (QR) test, which must be implemented prior to a SQRT computation.
It makes Smart algorithm inefficient. The essence of our proposition is thus to present a new QR test and an efficient SQRT algorithm to avoid all the overlapping computations. The authors devised a SQRT algorithm for which most of the data required have been computed in the proposed QR test. Not only there is no computation overlap in the proposed algorithm and the proposed QR test, but also in the proposed algorithm
over GF(p(2)) (4 | p | 1) some computations can be executed in GF(p); whereas in Smart algorithm over GF(p(2)) all the computations must be executed in GF(p(2)). These yield many reductions in the computational time and complexity. We implemented the two QR tests and the two SQRT algorithms over GF(pm) (m=1, 2) in C++ language with NTL (Number
Theory Library) on Pentium4 (2.6GHz), where the size of p is around 160 bits. The computer simulations showed that the proposed QR test and the proposed algorithm over GF(p(m)) were about 2 times faster than the conventional QR test and Smart algorithm over GF(p(m)).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005A Scheme to Classify Clouds with the Depolarization Ratio andBackscattering Coeffcient Measured by Lidar93101ENKengoIokibeYoshitakaToyotaOsamiWadaRyujiKoga10.18926/14158The optical properties of clouds were measured with a polarization Mie lidar during April, 2004 and investigated to categorize the particles detected by the lidar. The cloud
layers were categorized into five types according to the depolarization ratios, as follows: (I) constant and small (less than 5%); increasing with height (II) nearly from 0% and (III) from about 50%; (IV) large and varying with the backscattering coefficient; and (V) sharply decreasing. This categorization of clouds enabled us to separate aerosols from clouds in a lidar signal. Comparison of the backscattering coefficients between clouds of types (I) and
(II) suggested that the depolarization ratio induced by multiple scattering in dense clouds does not depend on the particle density. Estimation of the particle phase for the five cloud categories was also examined.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712721993An Expert System for Determining Precedence Relation in Assembly19ENYasuhiroKajiharaHirokazuOsaki10.18926/15399Precedence relation in assembly has been determined by experience only. Now, an expert system is developed for determining such precedence relation. The conjugate states of the units of a product are shown in face frames and unit frames following the frame model. Seven rules are formulated. They consider geometrical interference of units, and make the precedence relation enable operation time to be shorter, and the number of JIG and substandards to be smaller. These rules are programized by computer language(PROLOG).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Alkenylation and Allylation of Aldehydes by Using an Ni/Cr/TDAE Redox System4146ENManabuKuroboshiMuneakiTanakaSuguruKishimotoKentaroGotoHideoTanaka10.18926/15164In 360 females, Bone mineral density (BMD) in lumbar vertebrae (L2-L4) was assessed by quantitative computed tomography (QCT), and the values obtained were compared with the frequency of vertebral transformation or
fracture as assessed by lateral scan image (scanogram) by X-ray CT. A correlation was observed between the frequency of vertebral transformation (or fracture) and lumbar BMD values : BMD under 125 mg/cm(3) was observed over 90% of women with vertebral transformation, and BMD under 70mg/cm(3) was found about 50% of them. These results suggest that decrease in BMD in lumbar vertebrae leads to vertebral transformation or fracture. Thus, measurement of BMD by QCT would be very useful in predicting vertebral
transformation or fractures.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713111996Structure of Dusty Plasma as Yukawa System Confined in One-Dimensional External Fields1933ENHirooTotsujiTokunariKishimotoChiekoTotsuji10.18926/15166As a model of dusty plasmas in external fields, Yuka.wa system in a one-dimensional external field is analyzed by molecular dynamics simulations and theoretical approaches. It is shown that particles form clear thin layers (sheets) at low temperatures and the number of layers changes discretely with characteristic parameters of the system, accompanying the rearrangements of whole system from nearly equipartitioned layers to also nearly equipartitioned layers. The number, positions and populations of layers are obtained as functions of characteristic parameters. The shell (sheet) model which has been successful for confined one-component plasmas is extended to this system and results of numerical experiments are reproduced to a good accuracy. The effect of cohesive energy in each layer is of essential importance to reproduce discrete changes in the number of sheets.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713021996Analysis of Quantum Waveguide : Effective Width and Height of Potential for Quantum Wires under Split Gates2125ENHirooTotsuji10.18926/15401In order to apply quantum waveguides to electronic devices, we calculate the electrostatic potential in the split-gate quantum wire and establish the relation between the electrostatic potential and the square well potential which is usually assumed in simulations of these waveguides. The height and width of the square well potential are expressed as simple functions of the gate voltage and their dependencies are clarified. The results may be useful in calculating the characteristics of
electronic devices based on quantum waveguides as functions of controllable parameters such as gate voltage.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713021996Yukawa System in One-Dimensional External Field2737ENHirooTotsujiTokunariKishimotoChiekoTotsuji10.18926/15402The behavior of the Yukawa system in external one-dimensional force fields is analyzed by the molecular dynamics simulation. The formation of layered structures at low temperatures is observed and the relation between the number of layers and characteristic parameters of the system is obtained. Since the Yukawa system serves as a model of clouds of dust particles in plasmas (dusty plasma) which play an important role in plasma processes of semiconductor engineering, the results may be useful to control the quality of semiconductor wafers in such processes. In simulations, periodic boundary conditions are
imposed in two dimensions and deformations of periodic boundaries are allowed in order to reduce the effect of boundaries without giving too much constraint on the symmetry.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712721993Design of Hump Profile in Railroad Classification Yard4158EN10.18926/15404The fundamental objective of this paper is to aggregate and establish a set of practical principles, guidelines, and procedures to clarify and improve classification yard design and to enhance the efficiency of the design process. The paper primarily addresses theoretical and technical aspects of hump yard height and grade design, placement of the switches and the retarders. It attempts to compile and document yard design procedures, based on the Theory of Energy Head and Energy Loss. This procedures are applicable to the design of new yards, rehabilitation of the existing yards of different types and sizes including manually operated as well as highly automated classification yards.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Diagnostic method for induction motor using simplified motor simulator4751ENYukihiroDoumaeMasamiKonishiJunImaiHidekiAsadaAkiraKitamura10.18926/15269In this paper, an identification method of motor parameters for the diagnosis of rotor bar defects in the squirrel cage induction motor is proposed. It is difficult to distinguish the degree of deterioration by a conventional diagnostic method such as Fourier analysis. To overcome the difficulty, a motor simulator is used to identify the degree of deterioration of rotors in the squirrel cage induction motor. Using this method, the deterioration of rotor bars in the motor can be estimated quantitatively.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Microscopic Surface Change of Polycrystalline Aluminum duringTensile Plastic Deformation715ENXiaoqunWangTakejiAbeNaoyaTadaIchiroShimizu10.18926/14135Roughening on free surface of polycrystalline metal during plastic deformation is closely related to the
inhomogeneous deformation in the respective grain at the surface. Uniaxial tensile tests are carried out on
annealed pure aluminum sheet specimens with various averaged grain sizes. The roughening is measured by
a 3-dimensional stylus instrument to examine the roughness change in both sides of specimen surfaces at each strain. The irregularities on one side are reversed on the backside, when the averaged grain size is as large as the thickness of the specimen. Discussions are made on the relation between the surface shapes of both sides adopting the cross correlation factor. The strains of respective grains are also measured from the grain boundary shape before and after plastic deformation. There are some deviations in the strains of the grains and their standard deviation increases with the applied strain.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Microscopic Observation of Plastic Deformation of Polycrystalline Aluminum by Laser Scanning Microscope18ENTakejiAbeIchiroShimizu10.18926/15344Free surface of polycrystalline metal becomes roughened after plastic deformation. The surface roughening is closely related to the inhomogeneity of polycrystalline metals, that is, to the inhomogeneous plastic deformation of respective grains. In the present study, inhomogeneous deformation on the free surface of polycrystalline aluminum specimen during uniaxial tension is studied. The inhomogeneous deformation of grains in the central area of the free surface of specimen is observed by the laser scanning microscope, while the inhomogeneous deformation perpendicular to the surface is studied by the laser scanning microscope as well as the stylus measuring instrument. It is shown that the surface roughness and the strain of respective grains increase with the applied strain. Discussions are made on the change in the surface roughness, the strain in each grain and the slip-line angles with the applied strain.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071341-22000Energy Distribution in Electrical Discharge Machining with Graphite Electrode1926ENAkiraOkadaYoshiyukiUnoIsaoOkajima10.18926/15359In EDM, the machining characteristics greatly depend on the energy distribution. Therefore, it is very important to clarify the energy distribution for understanding various phenomena in EDM. In this paper, the energy distribution in EDM with graphite electrode is investigated by measuring the temperatures of electrode and workpiece. Experimental analysis shows that the material removal rate depends on energy density while the electrode wear greatly depends on the adhesion of heat resolved carbon from machining fluid, and the energies distributed into electrode and workpiece are almost constant regardless of pulse duration.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071341-22000Cytocompatibility of Silicone Elastomer Treated with Hydrogenperoxide Containing Tantalum Chloride3943ENSatoshiHayakawaYukiShirosakiTakeshiYabutaKanjiTsuruAkiyoshiOsaka10.18926/15363Silicone elastomer was chemically treated at 60Ž for 7 days with 30 wt% H(2)O(2) solutions with or without TaCl(5) and soaked for various periods in a simulated body
fluid(Kokubo solution) up to 21 days. Apatite formation ability of the surface of the silicone elastomer specimens was investigated with thin-film X-ray diffraction and FT-IR
reflection spectroscopy. These silicone specimens did not deposit apatite or calcium phosphates, irrespective of chemical treatment. Osteoblast-like cells (MC3T3-El) derived from mouse were cultured on the specimens at 36.5Ž under 5%C0(2) and 95% humidity. Similar degree of proliferation of cells was observed at 7 days among three specimens, while the no treatment specimen after incubation for 5 days showed a lower degree of proliferation than the silicone treated with 30 wt% H(2)O(2) solutions with or without TaCl(5). Alkaline phosphatase activity of the cells proliferated on the no treatment specimen was lower than those of the silicone treated with 30 wt% H(2)O(2) solutions with or without
TaCl(5). These results indicate that the cytotoxicity of the silicone could be improved by the chemical treatment with 30 wt% H(2)O(2) solutions with or without TaCl(5).No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713021996A Simple Model for Oxygen Conduction in Some Perovskite Compounds3943ENChiekoTotsuji10.18926/15405A simple model for oxygen ion conduction in perovskite compounds is proposed. The potential for an oxygen ion is calculated as the sum of the long range Coulomb potential and short range repulsive potential in a cubic lattice. The activation energy is estimated as the difference in the values of potential at the barrier and at the stable site. When appropriate conditions are satisfied, the activation energy has a minimum as a function of lattice constant in accordance with recent experiments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Bioactivity of Nb(V) and Ta(V)-Doped Calcium Silicate Glasses3944ENSatoshiHayakawaChikaraOhtsukiAkiyoshiOsaka10.18926/19594Nb(2)O(5)-and Ta(2)O(5)-doped calcium si1icate glasses were soaked for various periods in a simulated body fluid(Kokubo solution) up to 30 days. Apatite formation ability of the surface of these glasses were investigated with thin-film X-ray diffraction and FT-IR reflection spectroscopy. The effects of these additive oxides on the bioactivity of CaO¥SiO(2) based glass were discussed. A small amount of Nb(2)O(5) and Ta(2)O(5) suppressed the rate of silica hydrogel layer formation and the apatite formation on the surface of the glasses. The rate of the apatite nucleation on the surface of Nb(2)O(5)-doped calcium silicate glass was slower than that on the surface of Ta(2)O(5)-doped calcium silicate glass. It was concluded that the decrease in the apatite forming ability of calcium silicate glasses by these additive oxides is attributed to the suppression of formation of silica hydrogel layer which plays an important role in apatite nucleation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Bioactive Calcium Borosilicate Glasses for Enameling Titanium4551ENAkiyoshiOsakaSatoshiHayakawaChikaraOhtsuki10.18926/19596The thermal expansion coefficient of some bioactive glasses in the system CaO-SiO(2)-B(2)O(3) were adjusted to be similar to that of titanium by controlling the composition. A glass of composition 45CaO¥30SiO(2)¥25B(2)O(3) was selected among those as the enameling glass. A slurry was prepared by mixing the glass powder and ethanal to be developed on titanium and heated at 740Ž for 30 min. Thus treated specimen was soaked in a simulated body fluid (Kokubo solutiion). FT-IR reflection and thin film X-ray diffraction analyses indicated apatite formation on the glass coating layer within 12 h of soaking in the fluid. Thus titanium could be provided with bioactivity due to the enameling.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071321-21998Study on Electrical Discharge Machining Characteristics of Coated Electrodes16ENChangningGuoYoshiyukiUnoAkiraOkadaTakashiTakagi10.18926/19628Low electrode wear EDM is attained by the adhesion of heat resolved carbon made from kerosine type machining fluid to the electrode end surface. This phenomenon, however, occurs only under long pulse duration. Therefore, the low electrode wear EDM under finishing condition is impossible so far. In the previous paper, the authors developed a turbostratic carbon electrode whose structure is very similar to the heat resolved carbon generated in EDM process and made it clear that the low electrode wear EDM was possible by using the electrode even under finishing condition. In this study, a carbon coated electrode and a SiC coated one which can be made rapidly at low cost were developed and their EDM characteristics were investigated. Experimental analysis pointed it out that both electrodes were effective in reducing electrode wear under finishing condition.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999Apatite Formation on Electrochemically Treated Titanium7984ENAkiyoshiOsakaSatoshiHayakawaKanjiTsuru10.18926/19677A titanium oxide gel was electrochemically prepared on Ti with a cell consisting of Ti as the working electrode, Pt as the counter one, AgCl as the reference one, and an aqueous solution of 0.1 mol/L Ca(NO(3))(2) as the electrolyte solution. The Ti electrode was kept at 9.5V for 1 hr for oxidation and subsequently kept at-3.0V for 10 min (Ca9.5-3.0):calcium ions were expected to be adsorbed at the latter treatment. Other Ti specimen was kept at -3.0V for 10 min (Ca-3.0). Both specimens were found so bioactive as to deposit apatite in 12 hr (Ca9.5-3.0) and in 1 day (Ca-3.0) when soaked in a simulated body fluid (Kokubo solution). Calcium carbonate detected on the surface of Ca9.5-3.0 caused no harmful effects on spontaneous deposition of apatite in the fluid.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713612001Observation of Orientation Change During Plastic Deformation of Polycrystalline Copper by EBSD Method16ENRyoujiKondouTakejiAbeNaoyaTadaIchiroShimizu10.18926/46995Change in crystal orientation and strain of individual grains during tensile plastic deformation are studied to clarify on the microscopic deformation behavior of polycrystalline copper. The orientation of grain is measured by electron backscatter diffraction (EBSD) technique in the scanning electron microscope. The principal strain of grain is also measured by obtaining the approximated ellipse of strain distribution. The deformation of grains dependent on their initial orientation and the rotation of the principal strain during uniaxial tension are clarified.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713612001Improvement of Biocompatibility of Silicone Elastomer by Surface Modification117121ENYukiShirosakiKanjiTsuruSatoshiHayakawaAkiyoshiOsakaSeisukeTakashima10.18926/47005ƒÁ-Methacryloxypropyltrimethoxysilane (ƒÁ-MPS) was grafted to silicone due to emulsion polymerization to induce Si-OH groups, in order to provide silicone with bioactivity spontaneous deposition of apatite in body fluid and to improve cytocompatibility. Apatite deposited on the grafted silicone within 7 days of soaking in 1.5 times as concentrated as the Kokubo solution. Osteoblastic cells (MC3T3-E1) were cultured on the specimens up to 7 days. After 5 days of culture, the number of MC3T3-E1 cells on the grafted specimen was much greater than that on the original specimen. These results indicated that the biocompatibility of silicone elastomer was improved by the grafting ƒÁ-MPS.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713622002Preparation of alginic acid layers on solid substrates for biomedical applications6772ENTomohikoYoshiokaKanjiTsuruSatoshiHayakawaAkiyoshiOsaka10.18926/47027Alginic acid was immobilized on ƒÁ-aminopropyltriethoxysilane-coated glass as a model substrate since an alginic acid layer was known to prevent cell adhesion. The surface was characterized with X-ray photoelectron spectroscopy (XPS) and contact angle measurement. The coated substrates adsorbed practically no calcium phosphates on their surfaces when soaked in a simulated body fluid (SBF) of Kolrubo recipe. Since calcium ions are one of the factors for blood clotting, the present alginic acid coating is one of the candidates to improve blood compatibility of clinical materials.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Mechanical Characteristics of Cast Ti Fiber-Reinforced Mg Composite18ENHiroyukiOkadaMoritakaHidaAkiraSakakibaraYoshitoTakemoto10.18926/15500Tensile strength and elongation of cast magnesium reinforced with titanium fiber were measured by tensile test. The pull-out test of a titanium rod partially embedded in a magnesium matrix was performed to evaluate interfacial bonding strength between magnesium and titanium. It was found that when the fiber volume fraction was changed from 1% to 14%, the tensile strength was improved with increase of volume fraction, while the improvement of elongation tended to be restrained beyond the volume fraction of 10%. The interfacial strength was revealed to be strong, and this was substantiated by the scanning electron microscopy showing an excellent wettability between the titanium fiber and the magnesium matrix.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712721993Simulation of Hump Performance in Railroad Classification Yard5971EN10.18926/15406The paper presents methods for simulation and examination of the performance of a classification yard, including both manual and computer-aided methods. Presented methods are applicable to the simulation and examination of full range of yards of different types and sizes including manually operated as well as highly automated classification yards.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Effect of Surface and Grain Boundary on the Reversion of Age-Hardened Al-15mass % Zn Alloy17ENAkiraSakakibaraTerutoKanadani10.18926/15407Reversion of the age-hardened Al-15mass % Zn alloy, in which ellipsoidal GP zones were formed, was investigated by hardness test. Ellipsoidal zones were reverted more quickly near the surface and grain boundary than in the interior, as spherical zones did. The results confirm their role as sources for vacancies in reversion.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Ultra-Micro Hardness Testing and Microscopic Deformationof Polycrystalline Aluminum919ENTakejiAbeTomoakiTsuboi10.18926/15346The evaluation of microscopic inhomogeneity of polycrystalline aluminum is performed by measuring the hardness in respective grains. The recently developed ultra-micro hardness tester is used and the effects of the test pattern, the indentation load and the indenting velocity are examined. Then, the relationship between the increase in the hardness caused by the work hardening and the deformation of respective grains are statistically investigated. The hardness testing mode in which the initial load is applied before the onset of measurement gives more stable results than the testing mode without the initial load. The test condition with the indentation load of 9.8mN and the indentation velocity of 0.2 ƒÊm/sec seems to be optimum and gives the least dispersion of the measured values in grains. It is shown that the hardness values of respective grains in polycrystalline aluminum as well as their dispersion increase with the applied plastic strain. Discussion is made on the microscopic deformation behavior of polycrystalline aluminum.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Laser Welding of Slices of Magnetic Circuit2128ENVolodymyrS.kovalenkoYoshiyukiUnoYasuhiroOkamotoM.AnyakinA.LutayKhaled Al.Shubul10.18926/15348In electric power industry, there is a problem of achieving stable joint in different components using high productive and efficient technologies. One type of these components is packages of slices for magnetic circuit of electric motors, transformers etc., which need reliable means for their fixing. Laser welding is proposed to solve this problem as an alternative for existing technologies. The development of the laser welding process is presented based on process simulation, study of heat history and comparison with experimental results. Laser beam additional scanning technique is proposed to improve the quality and efficiency of the joining operation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Synthesis of Poly(ethylene-block-vinylalcohol)for Use as Amphiphilic Film Surface at High Temperature2934ENKaoruShimamuraTetsuyaUchida10.18926/15350Poly (ethylene-block-vinyl alcohol), which consisted of both hydrophobic and hydrophilic blocks, was prepared by using polyethylene single crystals as starting material. Polyethylene single crystals reacted with fuming nitric acid resulting in long methylene chains with functional groups such as COOH and NO(2) at the ends (the chain length were almost same as the lamellar thickness of polyethylene single crystal). The functionalized methylene chains were allowed to react with 4-aminostyrene to give corresponding amides, i.e., methylene chains with vinyl groups at the ends (macromer). The macromers were extended by block-copolymerization with vinyl acetate, then saponified resulting in PE/PVA block co-polymer. The block copolymer was molded into sheets which were subsequently heat-treated in contact with hydrophilic or hydrophobic media. Depending on the media, the sheet surface changed at high temperature reversibly from hydrophilic to hydrophobic and vice versa. The surface property was fixed by quenching because both blocks were able to crystallize. Thus the surface of this material can be tailored for various purposes at high temperature, and then used in stable at room temperature.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Scanning Probe Microscopy of Poly(p-phenylene benzobisthiazole) Lamellar Crystal3540ENKaoruShimamuraTetsuyaUchidaTomohiroInoue10.18926/15352Rigid polymer, poly(p-phenylene benzobisthiazole), formed lamellar crystals where the molecular chains were oriented perpendicular to the lamellae. It was supposed that, because of wide distribution in the chain length, the lamellar surface bristled with the chain cilia among which many voids were included. Crystallographically, this region
afforded us a transitional structure from full to deficient packings of chains. The structure was analyzed using the scanning probe microscope. In the course the method for imaging one molecular chain end was developed. From the images it was concluded that an isolated long cilius did not move so violently at room temperature.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071341-22000Falling Snow Melting Characteristics of Warm Water Flowing along Sheet Channels Spread on a Roof112ENHideoInabaAkihikoHoribe10.18926/15354The experiment for investigating the falling snow melting characteristics of warm water flowing along sheet channels spread on a roof was performed in Tookamachi city, Nigata prefecture from February 6 to February 7, 1995. The sheet surface temperatures at 11 positions in 3 channels were measured. A physical model for a gas-water-snow system was constructed to compare the predicted results with the measured ones. A fully spread uniform water film in the sheet channel was observed in the experiments. The experimental results elucidated that it was feasible to use warm water flowing along sheet channels for melting falling snow on roofs. The temperature drop in the sheet
channel mainly depended on the snowfall intensity, atmospheric temperature and wind speed. Under the influence of the roof edge, the temperature drop in the channel next to the side edge was much larger than that in middle channels. A water-snow two phase flow or a snow covered frozen water was experienced temporarily in the lower reaches of the water flowing channel. These suggest that a larger water flow rate is needed for the channel next to the roof edge, and a higher inlet temperature or a greater water flow rate is required for a severe weather condition. There was reasonably good agreement between the measured and predicted water temperatures.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071341-22000Effect of Specimen Thickness on Aging and Fatigue Strength of Al-Zn Alloys1317ENAkiraSakakibaraTadashiTanimotoTakahisaMatsushimaNorioHosokawaTerutoKanadani10.18926/15356Repeated tensile fatigue strength of the low temperature age-hardened Al-Zn alloys is investigated varying the specimen thickness. Fatigue strength of the age-hardened specimens decreases with the specimen thickness when the
specimen is thinner than a certain thickness, whereas fatigue strength of non age-hardened specimens, i.e., pure aluminum and dilute Al-Zn alloy, does not depend the specimen thickness. The dependence of fatigue strength on the thickness of age-hardened specimen is considered to be caused by the decrease of the strength of specimen as a whole, as a result of increase in volume ratio of the soft surface layer formed after age-hardening with decreasing specimen thickness.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Focusing Characteristic Analysis of Circular Fresnel Zone Plate Lens5361ENYukioKagawa10.18926/15357Fresnel zone plate lens (FZPL) has widely been used in electromagnetic antenna applications. Most analysis method based on the potential (scalar) wave approximation has
been applied to a few very limited and simplified cases. The present paper analyzes the FZPL in more general form including the diffraction and transmission using the method
of moments (MoM). The focusing gain characteristics in the oblique incidence as well as in the normal incidence are considered. The MoM solution using the three-dimensional
vectorial formulation requires a large memory space for the FZPL as it is operated at a short wavelength. This is simply overcome by using an iterative conjugate gradient
method for the numerical evaluation. The MoM solutions are compared with the other solutions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Nonorthogonal Tight-Binding Molecular Dynamics for Si(1-x)Ge(x) Alloys6375ENChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/15358We present a theoretical study of Si(1-x)Ge(x) alloys based on tight-binding molecular dynamics (TBMD) calculations. First, we introduce a new set of nonorthogonal tight-binding parameters for silicon and germanium based on the previous work by Menon and Subbaswamy [Phys. Rev. B 55, 9231 (1997); J. Phys: Condens. Matter 10, 10991 (1998)]. We then apply the method to structural analyses of Si(1-x)Ge(x) alloys. The equilibrium volume and atomic structure for a given x are obtained by the TBMD method. We also calculate the bulk modulus B, elastic constants C(11), C(12) and C(44) as a function of x. The results show that the moduli vary monotonically, but nonlinearly, between the values of Si crystal and Ge crystal. The validity of the results is also discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995Low Temperature Age-Hardening of Al-12mass % Zn-0.5mass % Cu Alloy14ENAkiraSakakibaraKeiyuNakagawaTerutoKanadani10.18926/15408Effect of addition of a small amount of copper to Al- 12mass % Zn binary alloy on the process of low temperature aging is studied by hardness test and transmission electron microscopy. Age hardening rate after quenching from various temperatures is slowed down by addition of 0.5mass % copper to the binary alloy. The hardness obtained after long aging, however, is increased a little by the addition of copper. The extent of soft surface layer formed by aging in the copper-added alloy is nearly
equal to that obtained in the binary alloy.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071341-22000Depolarization properties of Asian dust (KOSA) measured hyLIDAR in Okayama in the spring of 19982737ENHeWeiRyujiKogaKengoIokibeOsamiWadaYoshitakaToyota10.18926/15360In spring of 1998, Asian dust was observed with a Mie LIDAR in Okayama University, which can measure depolarization ratio. Three events of intense Asian dust were occurred in the period and medially detailed structure of atmosphere was found after examining records. Asian dust was distinguished from water droplets and the possibility to study three dimensional dynamic structure of atmosphere were demonstrated.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Molecular Dynamics of Yukawa System using the Fast Multipole Method7795ENChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/15361In order to perform the large-scale molecular dynamics simulation of the Yukawa system, a mathematical expression for molecular dynamics using the fast multipole method is described. The model simulations are also performed to test
the performance of our implementation of the FMM.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999Inspection Method by Comparing CAD Figure with Processed Image97103ENMitsuruJindaiHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawa10.18926/15297We propose the recognition method of bridge soldering base metal on the circuits by comparing CAD figure and input image of image processing to locate the soldering iron tip accurately to secure the high quality Firstly, three dimensional CAD assembly drawing of circuits which are assembled perpendicularly in each other is projected on an imaginary two dimensional screen which is vertical to the optical axis of the camera The projected image is used as the standard CAD figure to inspect the location of the bridge soldering base metal. The positions among the bridge soldering base metals show the line state. So this line (connecting line) is used as the reference line to inspect the location of the bridge soldering base metal. The characteristics of the standard figure are represented by the connecting line, edge line and center points of base metal. Secondly, the position and gradient of connecting line among bridge soldering base metals in the input image is estimated. And the position of base metal and assembly accuracy of circuit units are calculated by comparing the shape and position of each base metal with its standard figure based on the connecting line Furthermore, the length between the opposite edges of the base metals are calculated to inspect the positions and the assemble accuracy of circuit units.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995Numerical Study on Transient Heat Characteristics of a Rectangular Latent Heat Storage Vessel512ENHideoInabaKoichiOzaki10.18926/15409Transient characteristics of the rectangular latent heat storage vessel packed with shape-stabilized phase change (solid-liquid) material (PCM) are investigated numerically
by solving the governing equations of both the PCM and the heat transfer medium(water) simultaneously as a conjugate problem with the finite difference technique. It's found that the heat storage characteristics are greatly affected by the flow direction of the heat transfer medium since the natural and forced convection coexists in the heat storage vessel. That is, it is classified that the effectively thermal efficiency of the latent heat storage system is obtained by the downflow along vertical PCM for heat storage process and the upflow for heat release process. The effect of the inlet velocity of heat transfer medium(water) on transient heat characteristics of the latent heat storage system is also revealed in the present study.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Abductive Proof Procedure with Adjusting Derivations for General Logic Programs97135ENSusumuYamasakiYoshinoriKurose10.18926/15362In this paper, we formulate a new integrity constraint in correlation with 3-valued stable models in an abduction framework based on general logic programs. Under the constraint, not every ground atom or its negation is a logical consequence of the theory and an expected abductive explanation, but some atom may be unspecified as a logical consequence by an adjustment. As a reflection of the integrity constraint with an adjustment, we augment an adjusting derivation to Eshghi and Kowalski abductive proof procedure, in which such an unspecified atom can be dealt with.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Characteristics of a Monoacylglycerol Lipase Isolated from Pseudomonas sp. LP7315 -Hydrolysis and Synthesis of Monoglycerides137146ENTakaharuSakiyamaTsuyoshiYoshimiAkiraMiyakeMidoriUmeokaAtsushiTanakaShoOzakiKazuhiroNakanishi10.18926/15364A monoacylglycerol lipase (MGL) was purified from Pseudomonas sp. LP7315 by ammonium sulfate precipitation, anion-exchange chromatography, and preparative electrophoresis. The purified enzyme was homogeneous on an SDS-polyacrylamide gel with a molecular mass of 59 kDa. Its
hydrolytic activity was confirmed to be specific for monoglycerides: the enzyme did not hydrolyze diand
triglycerides. MGL was found to be stable even after l-h incubation at 65Ž. The hydrolytic activity depended not only on temperature and pH but also on the type of monoglyceride used. MGL also catalyzed monoglyceride synthesis at 65Ž in a solvent-free two-phase system, in which fatty acid droplets were dispersed in the glycerol phase with a low water content. The synthetic reaction
proceeded at a constant rate for approximately 24 h and reached an equilibrium after 48 h of reaction. The initial rate of the synthetic reaction depended on several factors: the type of fatty acid used as the substrate, the amounts of fatty acid and glycerol, and the concentration of MGL in the glycerol phase. To analyze the effects of these factors, a kinetic model was developed based on the assumption that the adsorption equilibrium of MGL molecules at the interface between the two phases is the rate-determining factor for the synthetic reaction. The model was found to yield a good approximation of the initial synthetic rate under various reaction conditions. The analysis suggests that the adsorption behavior of MGL onto the interface had a large effect on the initial rate of the monoglyceride synthesis.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001The role of interhelical cleavage for insecticidal activityof Bacillus thuringiensis Cry4A toxin147154ENMasashiYamagiwaHiroshiSakai10.18926/15366The Cry4A toxin is a dipteran-specific insecticidal protein produced by Bacillus thuringiensis subsp. israelensis as a protoxin of 130 kDa. Its active form is a heterodimer of 20- and 45-kDa fragments which is generated by an interhelical cleavage of a 60-kDa intermediate at the position of Gln236 between ƒ¿5 and ƒ¿6 helices in domain I. On the other hand, Cry1Aa, which is also produced as a 130-kDa protoxin but toxic to lepidopteran larvae, was processed into the active 60-kDa fragment with no additional cleavage. To investigate the role of the intramolecular cleavage of Cry4A for its insecticidal activity, the loop between ƒ¿5 and ƒ¿6 of Cry4A which includes the cleavage site was substituted for the corresponding region of Cry1Aa. The resulting mutant designated GST-60Loop was expressed as a GST-fusion protein. A difference of the processing profile was observed between GST-60 and GST-60Loop in the in vitro digestion assay by trypsin, and the insecticidal activity of GST-60Loop was two-fold lower than that of GST-60. These results suggested that the interhelical cleavage of Cry4A promoted the toxicity against C. pipiens larvae.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995A Logical Problem Decomposing Method for Decision Makers917ENHirokazuOsaki10.18926/15367Decision Support Systems (DSS) have been taken as hopeful support tools for decision making for more than 20 years. There are a lot of literatures on DSS, but most of them are not so practical as the designers expected. This paper points out the crux of this situation and argues that the research on DSS should pay some more attention to the decision making activities before the model using stage. A method named "Problem Situation Decomposing Graph (PSDG)" is presented in this paper for helping the decision maker(DM) elicit the decision making problems. A PSDG is an acycle AND/OR logical directed graph, and which includes all the factors affecting the problem situation based on the DM's knowledge. The logical nodes and parameter determining methods in PSDG can reflect the DM's decision making style. This paper introduces some basic concepts of PSDG, discusses some of its characteristics, and proposes a logical adjacency matrix for PSDG representation and analysis.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Principle of Biodynamic Analysis Using Human Limb Electrical Impedance1924ENTakaoNakamuraYoshitakeYamamoto10.18926/15369This paper describes a new measurement method and principle of detection of biodynamics using bioelectrical impedance method based on four-electrode technique with sinusoidal constant current. This method uses a human body itself as a part of the sensor. First, we show a bioelectrical impedance measuring device and the change of bioelectrical resistance is measured in human movement. Second, we proposes a principle of detection of biodynamics based on correspondence of magnitude, form and stability of movement to impedance waveform. Hence we can use this method for the judgement of sports skill using the impedance characteristics.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712721993Design of an Adaptive Observer to Estimate Unknown Periodical Disturbances7385ENAkiraInoueShiroMasuda10.18926/15370This report deals with the problem of designing an adaptive observer for estimating unknown periodical disturbances. This is very practical problem because in the area of control of servomechanisms such disturbances are always encountered. When the disturbance cannot be directly measured or eliminated at the source it is necessary to perform a prediction. When a periodical disturbance is present the frequencies appear as unknown parameters and they have to be identified. In order to identify the unknown parameters, it is necessary to transform the composite system model, which contains the models of the controlled system and the disturbances, into observable canonical form. In addition, an inverse transformation is required to calculate the estimates of the present disturbances. In this report, firstly, a review of an adaptive observer for estimation of unknown periodical disturbances is presented. Later a calculation of the disturbance estimate is derived using the algebraic programming system REDUCE. The proposed method here allows to perform all the necessary transformations and to obtain the disturbance estimation without using the transformation matrix. The calculations of these transformations are complicated and, hitherto, there is no simple method to perform them. The results of disturbance estimation are illustrated by two examples.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Identification of Electric Charge Distribution Using Dual Reciprocity Boundary Element Models2533ENYukioKagawa10.18926/15372Identification of unknown electric charges or sources distributed in space is made from the data observed over the field boundary using dual reciprocity boundary element models. The inhomogeneous term of the Poisson field can equivalently be expressed as the linear combination of the functions associated with the particular solutions to transform into Laplace equation. For the solution procedure, the variational formulation is employed, in which the regular boundary integral approach is incorporated to avoid the singularity. Numerical examples are presented to demonstrate the availability and the capability.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Finite Elements with Divergence-free Shape Function and theApplication to Inhomogeneously-loaded Waveguide Analysis3546ENYukioKagawa10.18926/15374Divergence-free shape functions are proposed for the finite elements, with which inhomogeneously-loaded and arbitrarily-shaped waveguides are analysed. The method is based on vectorial finite element formulation employing edge elements. The shape functions used for the approximation of the fields are shown analytically to be divergence-free and as an evidence, the non-physical solutions that appeared in the longitudinal component finite element formulation have been shown to be absent. To show the validity of the elements, application is made for the analysis of rectangular waveguides loaded with dielectric slab and a waveguide with curved structure. The solutions obtained are compared with the analytical ones or the solutions reported elsewhere. The degree of accuracy has been found satisfactory.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Regular Boundary Integral Formulation for the Analysis ofOpen Dielectric / Optical Waveguides4762ENYukioKagawa10.18926/15377Regular boundary element method is employed for the variational formulation of Helmholtz equation that governs the waveguiding problems. Like in the Charge simulation method, in this method, the source points associated with the fundamental solutions are allocated outside the domain so that the singular integrals which occur in the standard boundary element procedure can be avoided. First, the formulation is developed for the two-dimensional scalar Helmholtz problem solving for the axial components of either electric or magnetic fields. The application of the formulation is shown for simple hollow rectangular waveguide and dielectric-slab-loaded rectangular waveguide. Then the formulation is extended for the analysis of dielectric waveguides of open type incorporating axial components of both electric and magnetic fields, for the solution of the propagating modes which are generally of hybrid types. To show the validity and quality of the formulation, it is applied to a circular step-index optical waveguide and a dielectric rectangular waveguide. Very close agreements have been found when the solutions are compared with the ones obtained by different methods. One distinct merit of the extended formulation is that it has been fixed to suppress the spurious solutions which are encountered while solved by the conventional boundary element method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Finite Element Analysis of Open-type Dielectric / Optical Waveguides6373ENYukioKagawa10.18926/15379Optical fibers or integrated optical waveguides have arbitrary cross-sectional index or refraction distribution. An efficient finite element method for analyzing the propagation characteristics of dielectric / optical waveguides with open boundary is presented. The propagation modes are hybrid, for which a variational expression is formulated in terms of the longitudinal electric and magnetic field components. Infinite elements are introduced to consider open boundary or to extend the region to infinity. Several specific examples are given and the results are compared with those obtained by other approximate methods. Very close agreements have been found.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Determining Minimal Polynomial of Proper Element by Using Higher Degree Traces197205ENYasuyukiNogamiYoshitakaMorikawa10.18926/15380Modern communication engineerings, such as elliptic curve cryptographies, often requires algebra on finite extension field defined by modulus arithmetic with an irreducible polynomial. This paper provides a new method to detemine the minimal (irreducible) polynomial of a given proper element in finite extension field. In the conventional determination method, as we have to solve the simultaneous equations, the computation is very involved. In this paper, the well known "trace" is extended to higher degree traces. Using the new traces, we yield the coefficient formula of the desired minimal polynomial. The new method becomes very simple without solving the simultaneous equations, and about twice faster than the conventional method in computation speed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991The Effect of Electrode Polarity on Electrical Discharge Machining Performance in Water920ENYoshiyukiUnoToshikatsuNakajima10.18926/15410Practical utilization of ram type electrical discharge machining in uninflammable fluid has been expected in place of inflammable kerosine type fluid for unmanned operation in a workshop. The electrical discharge machining performance in deionized water is experimentally investigated on the basis of the analysis of the crater generated by a single pulse discharge. The experimental analysis makes it clear that the electrical discharge machining performance in deionized water is greatly affected by the electrode polarity. The metal removal rate in the normal polarity machining is higher than that in reverse polarity machining, while the electrode wear rate in the normal polarity machining is greater than that in reverse polarity machining. Therefore the electrode polarity should be properly selected according to the purpose of machining.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995A Method for Designing the Supplying Method of Parts to an Assembly Line1321ENHirokazuOsakiYasuhiroKajihara10.18926/15411We propose a method to design the supplying method of parts to an assembly line. Three types of supplying model (Serial, Parallel, and Mixed) are proposed based on the relation between the area of part and that of the transportation equipment. The part is supplied by the pallet on which the all parts of one product are arranged or by the lot of one part. AGV or conveyor are used to transport the pallet. The supplying model is evaluated from the total transportation cost calculated from the price of the transportation equipment and of land.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001A Group Signature Scheme with Easy Membership Canceling207212ENToruNakanishi10.18926/15382In the group signature scheme with a trusted party, a verifier can determine whether or not a signature is made by a member of the group, but cannot identify the member who signed the signature. In case of dispute later on, the signer can be identified by the trusted party. However, for efficient group signature schemes proposed so far, removing a member from the group can be not efficiently performed. In this paper, a group signature scheme with an easy membership canceling is proposed. By sending a request to use a resource together with the group signature on it to the manager of the resource, the manager can control anonymous accesses to the resource. In such an application, the proposed group signature scheme is suitable for canceling of the access privilege.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Electronic Structure of Mixed Perovskite Oxides8997ENChiekoTotsujiHirooTotsuji10.18926/15383Based on the tight-binding method, electronic bands of the mixed perovskite oxides are calculated in order to develop the electronic theory of ferroelectric phase transitions in these mixtures which are difficult to describe within the phenomenological theories. Diagonal elements of Hamiltonian matrix of parent materials are assumed to differ by 0.1eV and mixtures are simulated by lattices of supercells containing 2(3) = 8 or 3(3) = 27 unit cells randomly assigned to either material. The width of the conduction and valence bands have maxima and the band gap has a minimum at intermediate mixing ratio. Results are in agreement with those of other analyses on random systems and even 2(3)-cell computation seems to serve as a first approximation for our purpose.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Experimental Collimation of Cerenkov SHG Blue Laser Beam with a Cylindric Mirror99110ENMingWangOsamiWadaRyujiKoga10.18926/15384A cylindric mirror was used, in place of a parabolic mirror, to collimate the crescent blue laser beam radiated from the Cerenkov SHG in channel waveguide configuration. The cylindric mirror radius is requested to be twice the focal length of the parabolic mirror. The focusing effect of the cylindric mirror in collimation can be compensated by slightly lifting the mirror in its normal direction. Under the condition that the mirror was declined by 5.56‹ and lifted by 25 ƒÊm, we got the@collimated beam with divergence angle less than 1.3 mrad. In the focusing experiment, the collimated beam was focused with spotsize of 1.8 ƒÊm. The details on the analysis and experiment are reported.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Direct Patterning of Ceramic Circuit Board with Q-Switched Nd:YAG Laser110ENYoshiyukiUnoShin-ichiroKubotaToshikatsuNakajimaKojiroOgataNobuhikoTada10.18926/15385Direct patterning of copper coated ceramic circuit board is experimentally investigated with Q-switched Nd:YAG laser in order to shorten the time of the trial manufacture of electronic circuit board and to adapt the flexible design change. It is pointed out that the fast direct patterning the speed of which reaches about 100 mm/s is possible if the repetition frequency and the average power are selected properly. Furthermore cutting off and/or drilling of ceramic board are also possible under the condition that the repetition frequency is less than 3kHz. This technique makes it possible the mask1ess patterning of ceramic circuit board which has been widely used recently in place of conventional glass-epoxy or phenolic resin circuit board, and it leads to the shorter time limit of delivery as compared with the conventional end-milling method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Facilitated Diffusion of Carbon-Dioxide in a Living Body Liquid Film2126ENShigeruNozuHideoInaba10.18926/15412A numerical study is performed for the facilitated diffusion of carbon-dioxide in an ultrapure water film flowing downward along a vertical surface. The model adopted for the present work includes the effects of the reaction rate for the hydration of CO(2)in a liquid. Comparison of the total concentration of CO(2) for different film thickness indicates that the effects of the hydration is more remarkable for the thinner liquid film.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Genetic Algorithm with Evolutionary Chain-Based Mutation and Its Applications111120ENMasahiroTanakaTetsuzoTanino10.18926/15386Mutation is one of the important operators in genetic algorithm. In traditional genetic algorithm, mutation is activated stochastically. In this way it is unknown and cannot be controlled for which individuals to be mutated. Therefore, it is unavoidable that some good individuals are destroyed by mutation and then the evolutionary efficiency of the genetic algorithm is dampened. Owing to this kind of destructivity of mutation, the operator of mutation has to be limited within a very small probability, and the potentiality of mutation is consequently limited. In this paper, we present an evolutionary chain-based mutation and a control strategy of reasonable competition, in which the heuristic information provided by the evaluation function is well utilized. This method avoids the blindness of stochastic mutation. The performance improved in this method is shown by two examples, a fuzzy modeling for the identification of a nonlinear function and a typical combinatorial optimization problem-the traveling salesman problem.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713021996Effect of the Soft Surface Layer on Fatigue Strength of LowTemperature Aged Al-2mass % Cu Alloy913ENAkiraSakakibaraTerutoKanadani10.18926/15387Fatigue strength of Al-Cu alloy was examined by a repeated tensile mode when the specimens were aged and reversion annealed. The specimen quenched from 723K and aged fully around room temperature showed fatigue strength which depended on the existence of soft layer, while the specimen quenched from 723K and aged in the same way showed fatigue strength independent of the existence of the soft layer. Fatigue strength of the specimen, of which the soft surface layer was removed, was the same for either quenching temperature. Fatigue strength became higher when the soft surface layer was thickened with reversion annealing for 600s at 323K after aging. The soft surface layer was thought to increase fatigue strength of the aged Al-Cu alloy as well as Al-Zn alloy.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Heat Transfer Characteristics of Two Phase ClosedThermosiphon for Geothermal Energy (1st Report: Measurement on Heat Transfer Coefficient)1126ENHideoInaba10.18926/15388To prevent freezing of road and aquaduct by extracting geothermal heat with two phase closed thermosiphon has been widely used in a cold area. Both heat transfer characteristics in the underground soil and function of the thermosiphon to extract geothermal heat have to be made clear for the purpose of the above system. This study is directed for the purpose to prevent freezing of fire hydrant and composed of the fundamental experiment and the empirical experiment. In the fundamental study, heat transfer behavior is studied experimentally in the small size filling bath representing the underground soil layer. After recording temperature distribution, heat transfer coefficient is measured, they are proceeded into the correlation between the dimensionless number of Nusselt, Rayleigh and Fourier. The fundamental study is described as the first report.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995Stability and Sensitivity Analysis in Convex Vector Optimization121131ENTetsuzoTaninoMasahiroTanaka10.18926/15389In this paper we provide some theoretical results on stability and sensitivity analysis in convex vector optimization. Given a family of parametrized vector optimization problems, the perturbation maps are defined as the set-valued map which associates to each parameter value the set of minimal points (properly minimal points, weakly minimal points) of the perturbed feasible set with respect to an ordering convex cone. Sufficient conditions for the upper and lower semicontinuity of the perturbations map are obtained. We also provide quantitative properties of the perturbation maps under some convexity assumptions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Heat Transfer Characteristics of Two Phase Closed Thermosiphon for Geothermal Energy (2nd Report: Heat Transfer Behavior on Site)2732ENHideoInaba10.18926/15390Heating and refrigerating technique such as snow melting of road and cold storage by utilizing temperature difference between underground soil and atmosphere is widely used[1-4] in a cold area. In the 1st Report, heat transfer characteristics of two phase closed thermosiphon for extracting geothermal energy is studied fundamentally. In the empirical study, heat extract rate is measured in connection with the change of atmospheric temperature utilizing real two thermosiphons on the site. Temperature distribution on the surface of the thermosiphon and underground soil around it is also measured. Based on the data of the empirical experiment, it is confirmed that prevention of freezing for fire hydrant can be achieved by geothermal heat utilizing two phase closed thermosiphon. Present paper describes the heat transfer behavior of the thermosiphon as the 2nd report.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Measurement of Methane Concentration in a Rice Paddy Field with a Tunable Diode Laser Absorption Spectrometry4553ENNaokiKagawaOsamiWadaXuHaiRyujiKogaHiroyaSanoKazuyukiInubushi10.18926/15392A prototype device based on the tunable diode laser absorption spectrometry was constructed and the atmospheric methane concentration near the terrain in a rice paddy field was measured. An open optical path of 50 m length was employed along with a PbSnTe diode laser. Diurnal change of methane density with 30 seconds temporal resolution was recorded associated with meteorological parameters. A feasibility was proven for a practical application for in situ study of atmospheric methane.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995An Expert System for Reducing the Variety of Parts in Multi-item Production2327ENYasuhiroKajiharaHirokazuOsaki10.18926/15413A method for reducing the variety of parts is proposed. The variety of parts in a product and the variety of parts among products are evaluated in consideration of some factors that influence the production cost. Rules are formulated for selecting parts which should be eliminated or whose designs should be changed to reduce these varieties. An expert system is developed based on this method for reducing the variety of parts.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992The Impact of JR Seto Ohashi Line on Residential Land Value8192ENHirofumiAbe10.18926/15396This paper aims to examine the impact of JR (Japan Railways) Seto Ohashi Line on residential land value. First, the study examines the trends in land value in the area along JR Seto Ohashi Line by applying the area comparison method. The method estimates the effect of JR Seto Ohashi Line on residential land value by comparing land values between the study area and the Okayama Metropolitan Area. Second, the property value method is applied to measure the effect of railroad construction. The effect is estimated with a residential land-value regression, which is calibrated using land value data along the Seto Ohashi Line. Finally, the results are compared with the empirical studies in the Greater Tokyo Region, and various features of the impact of railroad construction on land value are identified.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995Evaluation of Eigenmodes of Dielectric Waveguides by a Numerical Method Based on the BPM4955ENAnisAhmedShinjiTaniguchiOsamiWadaMingWangRyujiKoga10.18926/15419For weakly guiding dielectric waveguides, the eigenmode field distributions are calculated numerically with a simple algorithm. In this numerical method, the transverse sampling space can be chosen arbitrarily, and hence a
narrow waveguide can be analyzed. The field satisfying scalar wave equation is expressed by the discrete Fourier transform and the mode eigenvalues and eigenfunctions are calculated by solving an eigenvalue equation numerically.
The validity of this method is checked for 2-D waveguides having step and parabolic or square index distributions. It is found that for the well guided TE modes of the slab waveguide, the accuracy of this method is remarkably good, but some discrepancies are found if the mode is near cut off. In the problems where the normalized guide index b is small, caution should be taken in applying the results of this numerical method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991The Model of Water Quality Management for the Hino River6173ENOsamiKawara10.18926/15420Lake Biwa is the largest lake in Japan, and one of the most important fresh water resources. The Hino River is the fourth largest river among the rivers which flow into Lake Biwa. The eutrophication of the lake has been warned since the 1960s. In order to improve the water quality of the lake, to decrease the loads through rivers is inevitable. Therefore, it is needed to predict the effects of measures to control pollutant loads and the influence of development in the basin on the loads from rivers before developing the basin and taking measures. This paper deals mainly with the model of water quality management for the Hino River and the effects of the development in the basin on the water quality. The model was formulated considering loads from forests, rice paddy fields, households, housing land, industrial factories. Using this model, a calculation system by a microcomputer was developed and the influence of urbanization of the basin was discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Urban Expressway Pricing under Constraint7594EN10.18926/15421Four radials-single ring urban expressway network is priced and, simultaneously, optimized in its spatial formation under the constraint that a balance must be kept of revenue and expenditure. The model consists of three sub-models: road system, car trip generation-attraction and traffic diversion. Network performance is assessed on two criteria; trip number criterion on which the aggregate number of car trips diverted onto expressway is maximized and travel hour criterion on which the travel hours of car trips integrated over the road system; surface and expressway, is minimized. Optimization is tried by numerical calculation for some sets of parameters in the model. The results are summarized as follows; (1) simultaneous optimization of price and spatial formation of the expressway network is possible on each of criteria, (2) trip number criterion produces lower pricing and smaller network while travel hour criterion does higher pricing and larger network, (3) optimum solution lies in a delicate relation of price and spatial network formation that comes from the balance constraint.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995One-Dimensional Classical Plasmas in Ion Traps, Ion Storage Rings, and Semiconductor Quantum Wires5765ENHirooTotsuji10.18926/15422As plasmas with extremely reduced dimensionality, properties of one-dimensional classical plasmas are analyzed in the domain of strong coupling and static and dynamic structure factors and the plasmon dispersion relation are obtained. These plasmas may be realized in Penning traps with sufficiently strong confinement and also in semiconductor quantum wires under appropriate conditions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991The Systematic Method for Constructing the IDEA BANK Based on the EBL95108ENHiroshiKawakamiTadatakaKonishi10.18926/15423This paper describes a method to construct IDEA BANK automatically. IDEA BANK is the data base of the "function-structure module" which is utilized in systematic conceptual design from Value Engineering perspectives. The method based on the Machine Learning EBL technique was evaluated and implemented for the IDEA BANK using SUN workstation. The practical implementation of the IDEA BANK acquisition was discussed after elucidating the problem and solution of the EBL technique in engineering design. In the IDEA BANK system, the structural features of an existing article are analyzed by hierarchically organized domain specific knowledge to yield a systematic explanation of how they function and attain their design goals. The explanation resulted in a generalized version of the Functional Diagram used in Value Engineering from which "function-structure module" can be extracted systematically.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995The Electronic Structure of C(60) Molecule -Structure of ƒÎ-electron Band-6776ENChiekoTotsuji10.18926/15424The ƒÎ-electron band of C(60) molecule has been obtained by the tight binding approximation. Application of molecular orbital wave functions derived on the basis of the optimized bond orbital model gives, with simpler calculations, the results in satisfactory agreement with those of previous theoretical analyses.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Radiative Characteristics of Frost Layer in Frosting and Defrosting Processes116ENHideoInabaHideoOtakeShigeruNozu10.18926/15425Radiative characteristics of the frost layer melted by radiative heat are experimentally examined. A frost layer is heated from above by the radiative heat from a halogen lamp set. Thermal radiation of the lamp has the wavelength spectrum characteristics similar to those of the solar radiation. The effect of the environmental temperature upon the frost melting process is clarified in experiments. The optical characteristics of reflectivity, absorptivity and transmissivity of the frost layer during the melting of the frost layer are measured using special measuring instruments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Freezing of Quiescent Water in a Horizontal Cylinder1724ENHideoInabaShigeruNozu10.18926/15427Heat transfer measurements were conducted during freezing of quiescent water in a horizontal cylinder. A horizontal cylinder with inner diameter of 61.1 mm is cooled by air in a constant low temperature room and time variations of the radial distribution of fluid temperature were observed. Experimental results for the velocity of the phase change interface, the time taken for complete freezing and apparent freezing heat transfer coefficient were compared with the simple theoretical model based on the quasisteady assumption.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713011995A Method for Standardizing Parts with Integer Programming17ENYasuhiroKajiharaHirokazuOsakiYoshiomiMunesawa10.18926/15365A method for standardizing parts is proposed. This method aims to reduce the sort of parts for cutting the manufacturing cost and for improving specifications of parts. Two linear mathematical programming models are proposed for standardizing the parts. One model aims at cutting cost half without causing any degradation of
mechanical specifications of parts. The other model aims at doubling mechanical specifications of parts below the acceptable manufacturing cost. These models are formulated in 0-1 integer programming forms. The integer programming model shows which part is common to other parts. An example is shown to demonstrate the use of the developed method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Methods for Tele-Operation of Mobile Type Maintenance Robot155161ENYoshiomiMunesawaYasuhiroKajiharaHirokazuOsaki10.18926/15368This paper proposes a concept of a mobile type maintenance robot (MMR in shortly) that is controlled by the tele-operation for assuring the safety and health improvement of work forces. The main components of this system are the industrial robot, an image processing unit, vehicle and computers for tele-operation. Our focus is paid on a method that determine a pathway to move every places where troubles would occur. This method makes it possible that the MMR could arrive any place in the factory with three times of turns at most. Additionally, turning radius of the vehicle is considered for correcting the pathway near the corners to make it possible that it arrives to the place accurately.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Development of Assembly Robot System for Flexible Belt-Shaped Subject163168ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawa10.18926/15371We develop an assembly robot system for assembling the flexible belt-shaped subject. An image processing method is developed to recognize the belt-shaped subject. This method is able to determine the grasping point and grasping angle for piking up a subject by a multiple hands unit. CAD information is used to determine the grasping point. The multiple hands unit is developed, which is able to grasp all grasping points of a subject at a time. In addition, the image processing method is used to judge whether a subject is fastened accurately at right position or not during the assembly.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001An Image Processing Method for Handling Subject Piled in a Container169175ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawa10.18926/15373We propose an image processing method for part handling robot for picking up subjects piled in a container. Line laser light is projected on subjects, and its external shape is detected by many segments of a line laser, and pitch, roll, and yaw angles of subject are recognized precisely. A priority rule is settled to choose one subject that is taken out. This rule is determined by considering the grasping space, the position of a subject, the movement space of hand and so on.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Cooperative Handling Robot with Human Beings177182ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawa10.18926/15375The focus of this paper is on the analysis of delivery motion of human, development of an image processing method based on the motion analysis and development of the cooperative delivery robot using the image processing method. The proposed image processing method uses two cameras, and it uses a stereo reconstruction technique for measuring position and postures of hands. In addition, this image processing method recognize the number of fingers extending consciously, so the cooperative human beings could choose the kind of tool which he wants by holding out his hand in front of cameras.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001A Method for Design Production System with Multi Energy Resources183189ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawa10.18926/15376This research proposes a strategy for reducing both electricity charge and environmental load by considering multi energy sources. The reduction of the contract electric demand is considered, and its differential cost is used for purchasing substitute power sources. Some variables, such as the amount of reduced contract demand, and amount of electricity are generated by each substitute power source. By using those variables, we formulate a simulation model that enables to minimize the energy cost and environmental cost.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992The study on the Evaluation of Eye Movement Using Computer Program2541ENMasaakiMatsudaHirokazuOsaki10.18926/15429The eye movement has been studied widely, because it gives various information about the characteristics of visual work. Almost all of those studies have concentrated on the distribution of the visual points, the direction and width of the saccadic movement and the fixation time of the measures. However there are few measures to evaluate the relationship between the visual objects and eye movement. Recently, the personal computer become portable and this makes it possible to analyze the many data and to show the results graphically on the experimental field. In this study, we propose a series of methods to evaluate how a subject looks at a visual field using the queue theory, and how often man looks at the central part of the visual field using the statistical two-dimensional ellipse. We developed the Pascal program on an personal computer(NEC PC9800). This program has 3 functions. One is the measurement of eye movement, the second is the calculation of the proposed measures and the third is the display of the results of these calculations.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071351-22001Disassembly System using an Impact Hammer for the Material Recycling191196ENYoshiomiMunesawaHirokazuOsakiYasuhiroKajihara10.18926/15378We developed the disassembly system that uses the impulsive load and disassembly tools to disassemble used appliances economically. The main components of this system are impulse hammer, a lift table and developed disassembly tools. Several types of disassembly tools are developed to punch out fastened portion on a part and cut off the shaft of screw or connection pin of IC-chip. A simulation model is proposed to explain and formulate how the fastening point of product is broken and cut. Three kinds of disassembly tools are designed. The actual disassembly system is developed by using proposed simulation models and disassembly tools.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995Backward Scheduling to Minimize the Actual Mean Flow Time with Dependent and Independent Setup Times8994ENKenjiSekoguchiShigejiMiyazaki10.18926/15430The present paper deals with a new perfomance measure, the actual mean flow time, defined as a mean of the elapsed time of each job counted from the start time on a schedule to the corresponding due date. For the one machine backward scheduling model with a common due date and independent setup times, LPT schedule is shown as the optimal solution for the proposed measure. An optimal
algorithm is presented for the case with dependent setup times on the basis of the algorithm by Arcelus and Chandra for a n / 1 / F forward scheduling problem. The proposed algorithm is coded in C-language and a computational experience is reported through a 16-bit computer.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713311998A Study on Robot System to Hand Surgical Intrument to a Surgeon in a Surgery (1st Report, Development of Surgical Instrument Recognition System)3137ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaShujiSeki10.18926/19610The nurse supporting robot system to prepare and hand surgical instruments to a surgeon is proposed to reduce work of nurse in a surgical operation. In this paper, the surgical instrument recognition system (SIRS) is developed to hand the surgical instruments to a surgeon by the robot. The characteristics ot the instruments are area of the instruments, ratio of minimum center-contour distance to maximum one and its outline contour, are recognized by using the image processing. Kinds of the instruments are distinguished by these characteristics.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713311998Recognition Index of Part and Unit by Discrimination Characteristics3945ENYoshiomiMunesawaHirokazuOsakiYasuhiroKajihara10.18926/19612In this paper, we propose a recognition index to evaluate the complexity of discrimination among parts and units. The parts and units are classified into some groups (the number of groups is shown as n) by one characteristic, such as color, shape, size and so on. The recognition index of each is denoted as log(2) (n+1) by the information quantity formula. The recognition diagram shows the classfication of parts and units into only one part and unit by the structure of a characteristic. Further we propose the line balancing method for assembly line based on the working time and recognition index.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713311998The Recognition Methods Combined Image Processing With 2D or 3D CAD Information (CAD/IP)4752ENMitsuruJindaiHirokazuOsakiYasuhiroKajiharaYosiomiMunesawa10.18926/19615In this paper, we propose the recognition methods by image processing using 2D or 3D CAD. In the case of 2D CAD, an object is recognized by comparing five characters calculated from the center of gravity and contour. In the case of 3D CAD, there are two recognition methods. Firstly 3D CAD figure is transformed into 2D CAD figures. And an object is recognized by comparing 2D CAD figures with inputted images. Secondly the three dimensional coordinates of vertexes on an object are calculated from the images taken from some cameras and compared 3D coordinates with those of 3D CAD figures and recognized the sort of an object.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712811993A Simple Model for Hydrogen-Bonding Ferroelectrics3950ENChiekoTotsuji10.18926/15435There are some substances in which their hydrogen bonds are considered to play quite important roles in their ferroelectric or antiferroelectric phase transition. These ferroelectrics usually have large isotope effects in phase transition temperatures and we expect the physics of hydrogen bonds is closely related to the effects. We propose a simple model describing the isolated hydrogen bond. Based on quantum-mechanical analyses of this model, we study the difference between the behavior of a proton and a deuteron in hydrogen bonds.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713311998A Method for Designing an Automatic Monitoring System for Unmanned Rooms5357ENHirokazuOsakiYasuhiroKajiharaYosiomiMunesawa10.18926/19616A method for designing a monitoring system with multiple cameras is proposed in order to supervise and recognize the progress of wide work area. First, a wide view camera is deveeloped by combining several usual cameras so that its visual angle could cover more than ƒÎ/2. Secondly, A method for determining the number and location points of cameras is proposed by considering the shape of monitored area and the installation cost of cameras. The monitored area is divided into three kinds of basic shape (rectangular form, L form and convex form). For every basic shape area, the camera is located at the vertex pasition, so that the whole area can be monitored by the camera.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999Intelligent Monitoring System Using Multiviewpoints for Teleperation9196ENYoshiomiMunesawaHirokazuOsakiYasuhiroKajihara10.18926/19682In this paper, we propose the method to determine the position of the 2 cameras for the multiviewpoints as the robot is the work place. The optical axit's direction of the 1st camera is determined in the base ot work contents in teleoperation. The multiviewpoints system uses the 2 camera units that aren't installed side by side, so that the direction of the 2nd camera is decided in the base of the angle between the optical axes' direction of 2 cameras. Next, the distance from the camera to the work place is determined according to the distance resolution of image on the monitor, and the camera type of which the point-blank range is not this distance is selected. And the efficacy ot this system is examined with an experiment.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999A Study of Facility Layout Method in Recycling Plant using AGV111119ENYoshiomiMunesawaHirokazuOsaki10.18926/19692Our country faces a serious problem of the environmental pollution by the production and the large quantity consumption of the industry product. The thoroughness of resources recycling has become necessary to solve these problems. As for the product design and the production control, how productivity should be improved has been discussed with extreme emphasis. But from now, as for the product design, both assemblability and disassemblability must be taken into consideration at the same time. And also in production management, it must be investigated how the products can be recycled in the low cost. Therfore, the facility layout method with two phases in recycling plant, which is composed of both the procedure for the layout of facility group and the procedure for the layout of intermal facility group by the optimal solution method and the suboptimal solution method by neural network is proposed in this paper.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115452011ContentsENNo potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712811993Determination of Clay Minerals by the Ignition Loss MethodUsing a Muffle Furnace5159ENIichiroKohno10.18926/15437A technique for determining the layer structure and content of clay minerals was developed based on the relationship between temperature, and moisture characteristics of clay minerals. Moisture content in standard specimens, prepared by mixing montmorillonite, kaolinite and quartz in various proportions, was determined by measuring weight loss after heating. Based on the results from differential thermal analysis tests, the ignition loss method was found to be widely applicable to clays with montmorillonite and kaolinite as the main components. Dehydration of constituent water occurred at 530Ž and 800Ž in two- and three-layered clay minerals, respectively.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992A Beam Focusing Antenna for the TE(0)n Mode High-Power Millimeter Wave7792ENOsamiWada10.18926/15439This paper describes a method to design an antenna to focus millimeter-wave beam generated by a gyrotron. The antenna, which has been proposed by the authors, consists of a stair-cut circular waveguide and two cylindrical reflectors; one is elliptic and the other is parabolic. Its principle is based on the geometrical optics though slightly modified to consider the diffraction effect. Results of low-power experiments agree well with the design on beam direction, beam width and the position of the focal point. At 35.5 GHz using TE(01) mode, a focused beam with half-power thickness of 13 mm x 10 mm was obtained. This type of antennas find applications to millimeter-wave scattering measurement in fusion plasma research and high- energy-density source for material heating.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Transport Simulasion in a Burning Tokamak Plasma93109ENAtsushiFukuyamaYoichiroFurutani10.18926/15441A one-dimensional tokamak transport code (TASK/TR) has been developed to analyze the evolution of a burning plasma accompanied with fusion reaction. This code deals with the electrons, deuterons, tritons, thermalized ƒ¿ particles, fast ƒ¿ particles and beam ions, separately, in order to describe the dependence of the reaction rate on the ion mixture ratio. As an energy transport model, the drift wave turbulence mode is employed. The heating and current drive by the neutral beam injection as well as the pellet injection for fuelling are also included. This code is applied to a reactor-grade plasma aimed at in the ITER project. The cases of an ignited plasma and a current-driven plasma are examined. The required power for full current drive is estimated. The effect of pellet injection, both fuel and impurity ions, is also studied.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Spectrum of Schottky Noise in Ion Storage Rings129138ENHirooTotsuji10.18926/15444The spectrum of Schottky noise in ion storage rings is analyzed as density fluctuations in effectively one-dimensional plasmas. Strong coupling effects in these plasmas are discussed in relation to experimental observations.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712621992Scattering by a Penny-Shaped Crack Subject to Oblique Incident Waves139150ENSohichiHirose10.18926/15445Scattering problems by a penny-shaped crack are solved using a time-domain boundary integral equation method, The crack is located in an infinite homogeneous, isotropic, linearly elastic solid, and is subjected to an oblique incident wave of either P-, SV-, or SH-wave, The hypersingular integral equation is solved to obtain near-field solutions as well as scattered far-fields. The accuracy of the present method is confirmed by comparing the near-field solutions for different arrangement of elements, Scattered far-fields are calculated for various incident waves, and their usefulness in quantitative non-destructive evaluation is discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712811993Numerical Simulation of Rock Toughness Testing129138ENTakeoTaniguchiSohichiHirose10.18926/15447The testing method of rock toughness is proposed by the international society of rock mechanics (ISRM), but the results may be influenced by the test pieces, and the details of the crack propagation and the stress intensity factors are not clarified through the testing. Also the experimental test requires tedious works for the preparation of test specimen and economical responsibility. The present study aims to simulate numerically the rock toughness testing which is proposed by ISRM. For this purpose, the authors propose a numerical method which can simulate the experimental testing, and they show the propriety of the proposed method by comparing the results with the experimental and other numerical methods. At the same time, they clarify the details of crack propagation behaviors in rocks, and show the change of the stress intensity factors. The proposed method is based on the displacement-type finite element method, and several techniques are introduced to obtain accurate solution of the mechanical behavior near the crack-tip area.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071221988One-Electron State of a Partially Ionized High-Z Ion1534ENYoichiroFurutaniHirooTotsuji10.18926/15449An effective potential of an isolated partially ionized high-Z ion, calculated within the framework of the statistical models of atoms, is injected into the one-electron Schrödinger equation, in view of evaluating the electron density and comparing it with the results of statistical models. Starting from this initial value, a self-consistent electron density is obtained on the basis of the density functional theory, where quantum natures of electrons are fully taken into account.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071221988Thermodynamic Sum Rules for Mixtures of Charged Particles3544ENHirooTotsuji10.18926/15450Several methods to derive thermodynamic sum rules for a system including charged particle are proposed and applied to charged mixtures as well as one-component systems. The validity of the statements is examined carefully with respect to the ordering in the powers of the wave number. As for the mixture of electrons and ions, it is shown how the aspect of the one-component plasma or the ionic mixture appears when electrons become strongly degenerate.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712821994Clusters in Low-Concentrated Al-Mg Alloy912ENAkiraSakakibaraTerutoKanadaniK.NakagawaY.Yokota10.18926/15452The state above the solubility temperature of GP zones of
Al-3mass % Mg alloy, which has a tendency for precipitation and preprecipitation at low temperature, was studied by resistivity measurement. Homogenization treatment at high temperature reduced Mg atoms in the surface layer. After quenching from 623K, the specimen was annealed sequentially at various temperatures above the GP zone solvus. The stationary resistivity obtained in annealing at a temperature was the same irrespective of the starting state and increased with decreasing annealing temperature. No precipitation was observed in the annealing. The results are not in favor of the segregation of Mg atoms to the dislocation loops but of the short range
clustering.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071221988Mode Choice In Interregional Occupational Person Trips6370EN10.18926/15454The paper is a case study mode choice in interregional occupational person trips. Disagregate behavioral model of logit type is applied to the occupational person trips from Tsuyama area in Okayama Prefecture to Osaka area. The model turned out to give asignificant explanation of the interregional mode choice characteristics. Travel time, travelling expenses and " with or wi thout heavy baggage " were found to be significant.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712311988The Study on the Evaluation of the Visual Work Using the Logistic Curve112ENMasaakiMatsudaHirokazuOsaki10.18926/15455Display equipment has been used as communication media in
the factory, office, and home. In order to communicate
effectively, it is necessary to clarify the characteristics
of eye movement in the case of looking at the display. The development of Eye Camera enables us to measure eye movement during work, so that we can collect the many data of eye movement during work. In this study, we proposed a method to evaluate the visual work using the distribution of visual points in X and Y axis. The cumulative distribution is approximated by the logistic curve which shows the symmetry and kurtosis by the parameter. The proposed method was applied to the three typical display models, that is, the digital meter model, reading model, and game model. In the digital meter model, the visual points were distributed symmetrically along the meters, and the symmetry and kurtosis of the distribution varied by the arranged direction of the meter. In the reading model, the visual points were distributed nearly symmetrically and uniformly in each axis and they were moved around the character and line from the period of spectrum analysis. In the game model, the visual points moved according to the target and were distributed symmetrically in the Y axis. And whether the target moved vertically or horizontally, the kurtosis of the distribution became equal in each axis.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712821994Cyclone Dust Collector with a Perforated Internal Rotating Cylinder2131ENKyojiYamamoto10.18926/15456An experimental investigation has been made of the cyclone dust collector with a perforated internal rotating cylinder. The size of the rotating cylinder is of 0.5D, where D is the diameter of the cyclone body, and is the same size as the outlet tube. The dust collection efficiency as well as the pressure loss has been measured when the inlet flow speed is 9 ~ 21 m/s and the rotating speed of the cylinder is 37 ~ 63 m/s. The velocity and pressure distributions were also measured. It is found that the collection efficiency decreases and the pressure loss increases as the rotating speed increases. It is also shown that both the inward radial velocity and the upward vertical velocity become large as the rotating cylinder increases its speed. As a whole, the rotation of the internal cylinder makes worse performance of the cyclone dust collector.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712821994Collimation of Cerenkov-SHG Blue Light with a Parabolic Mirror3344ENMingWangAnisAhmedOsamiWadaRyujiKoga10.18926/15458Proposed here is a convenient optical system to collimate the crescent shaped blue laser beam radiated from a Cerenkov SHG in channel waveguide configuration. This collimation system is consisted of a parabolic mirror and has a very large tolerance to the mirror displacement. The anisotropy of the nonlinear crystal on which the waveguide is fabricated has been taken into account. The optimum mirror location is given to obtain a collimated blue laser beam with an aberration less than 0.07ƒÉ. By using an objective lens, the collimated beam can be focused down to a thin beam with the spot size less than 1ƒÊm.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712821994Note on the Piezoelectric Constant of PbZrO(3)-PbTiO(3)(PZT)5358ENChiekoTotsuji10.18926/15461One of the best known solid solution of perovskites is the PbTiO(3)-PbZrO(3) system which is usually abbreviated as PZT. In the phase diagram of this system, there is a drastic phase change from tetragonal to rhombohedral at the molar ratio around 50:50. The PZT crystals are widely used as a practical piezoelectric material because of its very strong piezoelectric effect near this morphotropic phase boundary. We try to explain this anomaly in piezoelectric constant by a phenomenological theory.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712311988Determination of Electrical Parameters for Skin during Galvanic Skin Reflex from Continuous Measurement6168ENYoshitakeYamamotoTatsumaYamamoto10.18926/15467Skin impedance satisfies the Cole-Cole arc's law. The change of skin impedance during GSR (Galvanic Skin Reflex) can be expressed by the change of equivalent parallel resistance approximately. Using these characteristics, the complicated change of skin impedance during GSR can be determined continuously from the measurement value in one frequency point.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712311988Plasma Oscillation in Semiconductor Superlattice Structure6982ENHirooTotsuji10.18926/15468The statistical properties of two-dimensional systems of charges in semiconductor superlattices are analyzed and the dispersion relation of the plasma oscillation is calculated. The possibility to excite these oscillations by applying the electric field parallel to the structure is discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712321989Wettability and Supercooling Phenomena of Ga18ENHidetoKamiyabuAkiraSakakibaraHironobuMaedaMoritakaHida10.18926/15469Surface tension (ƒÁ(L)) and contact angle (ƒÆ) of gallium related to wettability on Teflon and other substrates (Al(2)O(3), SiO(2), glass, graphite, BN, AI, Ni, As etc.) were investigated. The values of Teflon were 0.70(6)N/m and 158‹ in pure argon atmosphere, and the ones of other substrates were listed in a table in this text. We were interested especially in the relative values, ƒÁ(L)'s, on the substrates as compared with ƒÁ(L) on Teflon substrate. Liquid Ga showed spreading wetting on pure Ni metal and adhesional wetting on Al (supposed to be covered by A1(2)O(3)) and on metallic polycrystal As. Surface tension of Ga was remarkably decreased by a kind of oxide contamination
due to oxygen in air. The surface layer coated by the contamination was of amorphous state nearly same as liquid Ga. The amorphous coat caused liquid Ga rather high supercooling of ¢T~35K. It seems that the contamination layer (oxide fi1m) smeared the crystal nucleation sites on the free surface of liquid GaNo potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Fundamental Study on Electrical Discharge Machining1324ENYoshiyukiUnoToshikatsuNakajimaOsamuEndo10.18926/15470The generation mechanism of crater in electrical discharge machining is analyzed with a single pulse discharge device for alloy tool steel, black alumina ceramics, cermet and cemented carbide, investigating the gap voltage, the discharge current, the shape of crater, the wear of electrode and so on. The experimental analysis makes it clear that the shape of crater has a characteristic feature for the kind of workpiece. The shape of electrode, which changes with the wear by an electric spark, has a significant effect on the shape of crater. The diameter and the depth of crater have a close relation to the discharge energy for alloy tool steel, black alumina ceramics and cermet, while those for cemented carbide are related to the discharge current. The shape factor which is the ratio of the depth to the diameter of crater is different for the work material.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989An Expert System for the Scheduling of a Flexible Assembly Line for Multi Item Products2539ENYasuhiroKajiharaHirokazuOsaki10.18926/15471An expert system, in which preconditions and rules are expressed in logical formulas, is developed to support the scheduling of an automated job shop type multi-item assembly line. This system has the foIIowing characteristics to apply any case of schedulings: (1)Forward scheduling orbackward scheduling can be made. (2)The criterion on the input order of products, the dispatching process at each assembly station, and the selection of products from a buffer can be selected from several priority criteria. (3)Layout, number and velocity of vehicles, and the capacity of each buffer can be changed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712321989A Design Method for Pin Holding Type Jig919ENHirokazuOsakiMasaakiMatsuda10.18926/15472Multi-item flexible manufacturing systems have been spread to correspond the short life-cycle and the diversification of products. Part handling plays an important role to operate multi-functional robot efficiently in these systems, and many jigs are widely used to hold a part. They should be exchanged at once according to changing products. In this paper, we propose a pin jig which holds a part with two pins, and design method of the position, length and diameter of those pins for a cylindrical part. This jig has the following characteristics. As a surface of the jig is inclined to use gravity, the part can be fixed without any external forces. Therefore the structure of jig becomes simple, and loading and unloading of a part becomes easy for a robot hand.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712321989An Applicability of Aggregate and Disaggregate Estimations to Mode Choice by Inter-regional Occupational Person Trips2132EN10.18926/15475Diversion model and disaggregate behavioral model of logit type are adopted as aggregate and disaggregate estimates, respectively. Diversion model is assumed as a binary choice process including diversion ratio function at each step in the process. Diversion ratio is assumed as a function of generalized-travel-time ratio. The function is identified with each of the two steps of diversion; diverson from rail and bus to car at first and from the rest undiverted to bus at second. The data used are those on inter-regional occupational person trips. Each function are found enough and/or critically significant in the statistical sense. At the begginning, sixteen characteristics variables are enrolled in disaggregate model, which are identified by use of the above data. Six variables are reached finally and are all reasonable. A brief comparison of goodness of fit to the data are made between two models.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712321989Flow of Rarefied Vapour past a Liquid Sphere3344ENKyojiYamamoto10.18926/15477This paper deals with the low Mach numbers flow of a rarefied vapour past a liquid sphere accompanied with condensation and evaporation at its surface. The linearized Bhatnager-Gross-Krook(B-G-K} equation is used for the analysis, and from it the integral equations of the density, temperature and flow velocities are derived. These integral equations are solved numerically over a wide range of the Knudsen number covering from the slip flow to the nearly free molecular flow. The drag on the sphere is also calculated and is compared with that of previous work.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712321989On Robust Incomplete Choleski-Conjugate Gradient Method And Its Modification4555ENTakeoTaniguchiKohjiFujiwara10.18926/15478This paper includes a solver for a large sparse set of linear algebraic equations which are obtained by the application of the finite element method to static structural problems. Proposed method is a modification of Robust Incomplete Choleski-Conjugate Gradient Method, which belongs to Preconditioned Conjugate Gradient Method suitable for supercomputers. Through a number of numerical experiments the authors show that Robust Incomplete Choleski-Conjugate Gradient Method sometimes fails in to obtain the solutions, secondly they clarify the reason of the failures from the theoretical viewpoint, and finally they propose a modification of the robust method by the introduction of the theoretical result. Proposed method is as effective as the original, and it can overcome the demerit of Robust Method which is clarified through numerical experiments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990A Method of Cubic Object Feature Extraction113ENTsutomuWadaToshiroNoritsugu10.18926/15480How to reduce and simplify the calculation for image recognition is a very attractive and important issue in order to realize the real time control of a robot based on the image recognition results. This paper describes a method of extracting 2 - dimensional geometrical features of cubic objects based on the normal vector distributions from the visual information obtained with the laser range finder to reduce the calculation of the image recognition. In this research a laser beam is scanned in the horizontal plane to which the cubic objects stand vertically and the laser spot is detected with a TV camera every sampling time. These spots make an intermittent locus which includes some special lines corresponding to the cubic objects. To extract the features of the cubic objects, we utilize the normal vectors formed on the locus. If some normal vectors distribute in the same direction and the origin of the normal vectors are very close to their neighbor's, these normal vectors can be classified into the same class, -the straight line class. Because the normal vectors on the neighbor surfaces of the cubic objects are vertical to each other, we use this property to determine the pair of straight lines which belong to the cubic objects. Making the histogram based on the normal vectors with the same direction, we obtain the peaks which are supported by the points on the cubic object surfaces. Then, the points can be extracted from the set of points on the whole locus inversely according to the relations with the peaks and the features of the cubic object can be extracted by applying method of least square to these extracted points. The experiments proved the availability of the proposed processing algorithm.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Analysis of the Radiation Characteristics of a Primary-Feed Waveguide in a Quasi-Optical Antenna for Circular TE(On) Mode8192ENOsamiWada10.18926/15481Are calculated the radiation characteristics of two types of primary-feed waveguides of millimeter wave quasi-optical antennas, which transform circular TE(On) mode into a linearly polarized beam. These antennas are utilized for heating and diagnostics of fusion plasma. Analysis is based on the Huygens-Fresnel principle, which takes the diffraction effect into account. For Convenience in analysis, a feed waveguide is divided into two sections, an uniform waveguide section and a visor section. Assuming that the diameter of the waveguide is several times as large as the wavelength and that the structure of the visor is open, the radiation field is approximated by superposition of direct radiation, and first and second reflection on the visor. Numerical results are presented and compared with experimental results. In these types of waveguides, the shadow section on the visor has a great influence on the radiation field. The results of calculation show that the length of the visor should be longer than that obtained by the geometrical optics, and the longer visor reduces the side-lobe level in the direction of the waveguide axis. The results agree well with those in experiments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Propagation Characteristics of Superlattice Potentials and their Optimization93105ENHirooTotsujiTerukiHatatani10.18926/15482Propagation of charged carriers in semiconductor
superlattices is analyzed on the basis of the effective mass approximation with appropriate boundary conditions at heterojunctions taken into account. Applying the finite element method, clarified are the effects of details of the potential profile, such as linear and smooth gradings and random fluctuations, on characteristics of superlattices which are expected to work as collector barriers and energy filters in electronic devices.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990Effect of Quenching Condition on the Growth of GP Zones in Al-lmass % Ag Alloy1521ENAkiraSakakibaraTerutoKanadani10.18926/15484Aging of Al-lmass % Ag alloy at 273K after quenching under various conditions was studied by measurement of electrical resistivity. Scattering of the quasi-equilibrium value of resistivity (p(e)) was not random but closely related to the as-quenched value (p(o)); P(e) increased with increasing p(o)' When the quenching temperature (T(q)) was lower than or equal to 773K, the state at p(e) was controlled substantially by the concentration of quenched vacancy. On the other hand, when T(q)>823K, GP zones formed during quenching played an important role, instead of quenched vacancies, in determining the state.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Trends in the Regional Structure of Manufacturing Industries in Japan115133ENHirofumiAbe10.18926/15485The rapid economic growth of Japan in the postwar period has brought about the over-concentration of activities in a few large cities, and local regions have been losing their economic vitality due to the regional differentials and the population loss. Regional development planning in Japan has sought to achieve a balanced growth of the nation through the development of industries in local regions. This paper aims to examine the regional structure of manufacturing industries in the postwar period and to
identify its current problems. Three methods, namely the analysis of coefficient of variation, the rateshare analysis and the shift-share analysis are applied using employment data of manufacturing industries for the years 1955 to 1985. Findings show that while the employment of manufacturing industries has been markedly decentralized from metropolitan to local regions, the disparities in growth rates still exist among regions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Numerical Simulation of Multicrack Propagation Behaviour in Steel Structure135152ENTakeoTaniguhiTsuyoshiSuetsugu10.18926/15487This paper describes the numerical simulation method of the multi-crack propagation behaviour which appear in a part of civil engineering structures with complex geometrical configuration like steel bridges. Proposed method can treat the interaction of several cracks which locate in a short distance each other, and the process of their growth can be grasped. The method is based on the finite element method, and the linear fracture mechanics is assumed. Proposed method includes following tools for the simulation of the crack propagation behaviour: Automatic Mesh Generators for 3-D, 2-D structural analysis, and 2-D crack propagation analysis, Multi-level Structural Analysis Technique, Estimation Method of the crack growth and the angle of cracks and the modelling method of traffic loadings. The validity of the method is investigated by comparing the result to the experimental one.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990Superconductivity Proximity Effect in Inhomogeneous Media5157ENHirooTotsuji10.18926/15490The superconductivity proximity effect in the dirty limit is revisited and equations and boundary conditions are obtained for the case of inhomogeneous media with continuously varying characteristic parameters.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Aging in Dilute Al-Si Alloys1116ENAkiraSakakibaraTerutoKanadani10.18926/15491Aging behavior of Al-0.23mass % Si alloy was studied by measurements of elecrical resistivity. Resistvity maximum was observed in the aging curves at 273K after quenching from various temperatures. Appearance of maximum and its dependence on the quenching temperature were attributed to the formation of GP zones. Even in a more dilute alloy as 0.01mass % Si, the maximum of resistivity was also recognized.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Film Continuity Problem on Journal Bearing Design1730ENTadatakaKonishiMitsuruBaba10.18926/15493Pressure distribution has been measured and analyzed to clarify the fundamental characteristics of "continuous oil-film" formed in a transparent journal bearing, into which oil in general use is supplied. Measured pressure mostly shows quasi-Sommerfeld distribution, which is characterized by downstream shift of pressure profile and underdevelopment of pressure trough compared with Sommerfeld distribution for perfect oil-film. Sommerfeld distribution is approximately observed only under limited
conditions : low eccentricity and low speed. Quasi-Sommerfeld state is rather common in "continuous oil-film", unruptured film formed by using practical lubricants, than Sommerfeld state. Continuous oil-film is accompanied by fine bubbles and is controlled by the growing up or down of the bubbles.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990Optimal Pricing and Planning of Urban Expressway System7187EN10.18926/15494A transportation planning way of approach is applied to optimal pricing and planning of urban expressway network. Two kinds of network are investigated ; four radials with one ring system and four radials with two rings system. The model is composed of three submodels ; road systell, trip generation-attraction and traffic diversion. Some iaplicative aspects are shown of the optimal solutions that maximize the aggregate number of the trips diverted to expressway under constraints ; equilibrium of revenue and expenditure and traffic capacity constraint. (1) traffic flow has the peaks at junctions on radial expressway that are adjusted to be equal to the traffic capacity. (2) two rings system realizes the larger aggregate number of diverted trips by lower toll rate than one ring system does. (3) well-located second ring has a remarkable effect on improvement in accessibility to expressway and (4) some parameters in the model have curious effects on the optimal system.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990The Structure of Interregional Migration in Japanese Regions : An Application of Multidimensional Scaling8998ENHirofumiAbe10.18926/15496Multidimensional scaling (MDS) has been used in a wide variety of research fields; psychology, political science, anthropology, marketing research, urban and regional planning, and so on. In practical terms, MDS is a statistical method to make a picture of the information in the data. It enables us to examine the "hidden structure" of a set of data. When the set of data is large, MDS is extremely useful, since it is easier and more informative to look at a picture than the data themselves. In this paper, MDS is applied to the interregional migration data of Japanese regions for the years 1960-85. Findings show that the two-dimensional configuration of regions estimated by MDS generally corresponds with the geographical locations of regions, and the structure of interregional migration was very stable over the study years 1960-85. It is also suggested that MDS is a useful tool to identify the relationships between regions using the spatial interaction data.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Control of Microscopic Superconducting Channel by the Proximity Effect4147ENHirooTotsuji10.18926/15497A possibility to control the microscopic superconducting
channel based on the proximity effect is theoretically shown by a simple one-dimensional analysis of de Gennes' equation for the order parameter.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Characteristics of Errors in Open and Closed Trilateration Nets4965ENChujiMori10.18926/15499Distance measurements have been more and more easy and accurate to carry out, and it is expected that distance mesurements may provide rather accurate results than angle measurements. Under these circumstances, caracteritics of errors in typical trilateration nets are investigated. The nets investigated are as follows: From single row of chains to pranimetrically extended nets in figure, open and closed networks with respect to external constraint, and with and without as to internal constraint. Computations are performed by use of the method of condition equations, and behaviours of error propagation and errors of coordinates of stations in the nets are shown in case of typical nets. For example, effects for decrease in error by composing a double row of chains and by enforcing external constraints are explained.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Mean Time Between Failure of Ring Arbiter with Requests Differing in Incidences7987ENYoichiroSato10.18926/15502In asynchronous arbiters, failures may happen, caused by metastable operations. The purpose of this study is to derive a formula to estimate such failures in a ring arbiter as mean time between failures (MTBF), under the condition that incidences of requests issued in all devices are different from each other. The operation of the arbiter is formularized by a markov chain. This chain is used to decide the probability at which each of possible failures contributes to MTBF. The sum of such probabilities gives the MTBF which can be represented as a sum of a finite number of terms. As an example, MTBF of a ring arbiter composed of 3 cells is shown.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991X-ray Topographs of Strain Field Induced by Locally Ion-Plated Films on Si Substrates915ENMasatoMikuniMoritakaHidaNorihideNishidaAkiraSakakibaraMasuoYamada10.18926/15503Strains induced in the Si substrates by TiN film were observed with X-ray topography. The image of the sample with TiN film 0.45ƒÊm thick was like that of a dislocation loop observed with transmission electron microscope. The images of the samples with TiN films 1.65, and 1.9ƒÊm thick were different; blackening spreaded in the <112> and <110> direction from the ring contrast in shape of four-lobed rosette pattern. Spreading extended 1.6 times longer than the radius of the ring contrast along the <112> direction. The strain field extended 0.1ƒÊm in depth from the top surface where TiN was plated. From the topographs of bent Si beam, it was found that the blackness was almost proportional to the strain. The strains induced by TiN film locally ion-plated were smaller than those observed
previously when TiN was ion-plated on the whole top surface of the substrate. Fine structures were observed in the topographs which could not be explained by the kinematical theory.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Fatigue Strength of Age-Hardened Al-Zn Alloys under Repeated Tensile Loading1723ENAkiraSakakibaraTerutoKanadaniToshiakiKaneedaNorioHosokawa10.18926/15506Effect of the soft surface layer that was formed on low temperature aging of Al-Zn alloy on fatigue strength was studied under repeated tensile loading. Vickers microhardness test revealed that there existed less hardened region in the vicinity of grain boundary and surface, and that the region extends 50 to 100ƒÊm from the surface inward. From the plot of the stress amplitude against the number of cycles to failure, it is concluded that the presence of less hardened surface layer strengthens fatigue resistance of the age hardened Al-Zn alloys containing 8 to 16mass % Zn under the repeated tensile loading.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Parallel Skyline Method using Two Dimensional Array99112ENTakeoTaniguchi10.18926/15507This paper presents an effective solver for a large sparse set of linear algebraic equations, which appears at the application of the finite element and the finite difference methods in engineering field. Proposed method is a family of SKYLINE METHOD, and for faster computation on the vector processors the original skyline is modified with respect to following three items; the use of inner products of matrix operations, the removal of unnecessary numerical operations and the introduction of two-dimensional array for storing the data of coefficient matrix.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991A Basic Study on Nonlinear Sound Propagation by Finite Element Simulation6980ENYukioKagawa10.18926/15512A finite element approach to the calculation of nonlinear sound propagation is proposed. Under the assumption of a weak nonlinearity, a linearized one-dimensional equation is considered. The equation is discretized in space, and is then solved for time by using Newmark-ƒÀ integration scheme, in which a numerical damping is devised. Some numerical demonstrations are made for the nonlinear sound propagation of a single-shot pulse in air. It is shown that the shock wave propagation is stably and accurately simulated by the introduction of the numerical damping.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Analysis of Superconducting Microstructures: Formulation8193ENHirooTotsuji10.18926/15513Numerical methods for the analysis of the proximity effect in superconducting microstructures in the dirty limit are formulated on the basis of the finite element method. One- and two-dimensional cases are considered and third order Hermite shape functions are used. The results are also applicable to investigations of electronic states in semiconductor superlattice structures.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Analysis of Superconducting Microstructures: Critical Temperature of Two-Dimensional Structures95113ENHirooTotsuji10.18926/15515Critical temperatures of two-dimensional microstructures with superconducting proximity effect in the dirty limit are evaluated for various geometrical constructions. As a numerical method, the finite element method is applied. Guidelines in estimating critical temperatures are given for the case where the decay of superconducting order parameter is either sufficiently slow or fast in comparison with the scale length of the structure.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Nested Dissection Method on Transputer115122ENTakeoTaniguchi10.18926/15516Nested dissection method is an elimination method for a set of linear algebraic equations with minimum fillins. Physically it divides a domain into four subdomains, and each subdomain is again divided into four. This procedure is repeated till all nodes are included in some subdomains. Using this characteristic, the authors examine the efficiency of the method on the transputer.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991Mesh Generation for Convex 3-Dimensional Domain123133ENTakeoTaniguchiChikashiOhta10.18926/15517The aim of this investigation is the proposal of 3D mesh generation method based on the Delaunay triangulation. The method is valid for the finite element modelling of any convex 3D domain into tetrahedra with optimum geometrical configuration. This paper includes the mathematical background of the mesh generation method, its detail, proposal of some efficient tools for faster and more rigorous computations, and some examples of the mesh generation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Crystal rotation behavior with fatigue crack propagation in copper films17ENKenichiShimizuTashiyukiToriiKokiIshida10.18926/17822Using a fatigue testing method by which fatigue cracks can be initiated and propagated in a film adhered to cover an elliptical through-hole in a base plate subjected to push-pull cyclic loads, annealed copper films with the thickness of 100ƒÊm and those reduced the thickness from the 100ƒÊm to 50ƒÊm by an electro-polishing were fatigued under a constant stress amplitude with a stress ratio of zero. The crystal rotation behavior with the fatigue crack propagation was investigated by measuring the crystal orientation around the fatigue crack initiated from the notch root before and after fatigue testing, using EBSD (Electron Back-scatter Diffraction) method. Then, the change of crystal orientation with fatigue testing was evaluated quantitatively from the misorientation between the crystal orientation matrix on the same point obtained before and after fatigue testing. As a result, the angle of the crystal rotation obtained from the region showing the high fatigue crack propagation rate was larger than that obtained from the region showing the low fatigue crack propagation rate for the film with the thickness of 100ƒÊm, while the fatigue crack propagated faster in the film with the thickness of 50ƒÊm than that with the thickness of 100ƒÊm regardless of the small crystal rotation angles with the fatigue testing for the film with the thickness of 50ƒÊm.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Dispersion Models and Electromagnetic FDTD Analyses ofNanostructured Metamaterials using Parallel Computer815ENChiekoTotsujiKenjiTsurutaHirooTotsuji10.18926/17826Metamaterial which has negative permittivity and permeability is investigated via computer simulations. Effects of the nanostructure on dielectric and magnetic properties of the material are taken into account by introducing the Drude-Lorentz model in the materials dispersion. We include multi-band process in the dielectric response in order to reproduce accurately experimental values of bulk Au thin film. Size effect on the dispersion is examined by comparing the model with that of a noble metal particle. Based on the dispersion model constructed, we analyze the electromagnetic response of nanostructured metamaterials to evanescent waves at microwave and optical frequencies via finite-difference time-domain simulatioins on parallel computer. A re- focusing and an amplification of the evanescent waves propagating through a metamaterial, consisting of metal
slab/vacuum stacking, is demonstrated for the frequencies of 30GHz and 744THz.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009FDTD Simulations of Acoustic Waves in Two-DimensionalPhononic Crystals using Parallel Computer1621ENKenjiTsurutaChiekoTotsujiHirooTotsuji10.18926/17829The finite-difference time-domain (FDTD) method has been applied to the calculation of the phonon band structure of two-dimensional (2D) phononic crystals, consisting of metal cylinders placed periodically in liquid. By comparing several combinations of materials for metal cylinder and liquid, we analyze the dependence of the band structures on sound speed and density of liquid media. Moreover, the negative refraction of the acoustic waves is observed at the interfaces between phononic crystal slab and the liquid. We find that an acousticglens effecthwith the slab appears due to the negative refractions. The relationship between the focal intensity in the lens effect and the band structure is discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Information Transfer and Entanglement Creation by Spin Chains: Effects of Noise and Asymmetry2226ENHirooTotsujiChiekoTotsujiKenjiTsuruta10.18926/17831For the transfer of quantum information and the creation of entangled states, the application of tuned spin chains, systems of spins with the nearest-neighbor coupling tuned so as to give high efficiency, has been proposed and some examples of high performance have been given by several authors. In this article, the effect of deviations from tuned values and the effect of resultant asymmetry are investigated through numerical simulations and theoretical analyses. It is shown that there exists a system where the transfer efficiency is comparable with exactly tuned ones and, at the same time, robust to noises in the coupling constants. It is also shown that the effect of asymmetry on the efficiency of entanglement creation is of the second order when the asymmetry is small.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Experimental Conditions for Observation of ThermodynamicInstability and Critical Point of Fine Particle (Dusty) Plasmas2731ENHirooTotsuji10.18926/17833When the Coulomb coupling between fine particles becomes sufficiently strong in fine particle plasmas, the isothermal compressibility of the whole system diverges and we have a phase separation and an associated critical point. Experimental conditions of fine particle plasmas, densities and temperatures of components and the fine particle size, are obtained corresponding to characteristic parameters around the critical point and the dependency on ion species and other factors is discussed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Tracking Control of Combination Vehicles with PreviewFeedforward Compensation3238ENShujiMabuchiMasamiKonishiJunImai10.18926/17835A tractor-trailer vehicle in the factory might move on the route determined beforehand. However, automation of a tractor-trailer vehicle is difficult so that it is necessary to consider the nonlinearity of a vehicle and a trailer. In this research, the effective tracking control
method of a tractor-trailer vehicle is proposed. The control method using time-state control form for a preview control is presented, and be applied a tractor-trailer vehicle with nonholonomic characteristics. Results of numerical experiments are presented to check effectiveness
of the proposed control method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Positioning Control of One Link Arm with ParametricUncertainty using Quantitative Feedback Theory3948ENTakayukiKuwashimaJunImaiMasamiKonishi10.18926/17837This paper presents method of the controller design for one link arm with parametric uncertainty. Recently, many manufacturing robots are operated in manufacturing facilities, with the aim of labor and cost saving or improvement of the productivity. Such robots need to have positioning performance of high precision. In condition that there is an uncertainty in plant dynamics, desired control performance may not be attained because the
controller is designed according to the mathematical model of a plant. So it is important that the designed control system have a robust control performance. In this paper, the robust controller is designed using Quantitative Feedback Theory (QFT) for one link arm with parametric uncertainty. Simulation experiments are run for control system designed by using QFT and conventional method. The results are compared with each other and it is found that the control system designed by QFT shows a robust performance and can suppress the unevenness of output against parametric uncertainty.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Position Control of 2-Link SCARA Robot by using InternalModel Control4954ENShinyaAkamatsuMasamiKonishiJunImai10.18926/17839In this paper, the controlled target is the SCARA robot with two links, and the object is fine control of the arm head position of the robot. To attain the object, Internal Model Control (IMC) is introduced. A nonlinear equations are for robot dynamics formulated by solving Lagrange equation, and is linearized to design control system by IMC. The controller of IMC is designed or synthesisted as the inverse system of the linearized model, and IMC filter model is selected. Also, reference filter is introduced to make the improvement of performance. The result of control performance by IMC is compared with that of PID numerically, accuracy and incoherency are confirmed.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Surface Defect Inspection of a Cutting Tool by Image Processing with Neural Networks5560ENShinichiroInoueMasamiKonishiJunImai10.18926/17841In this research, an image processing method and a system for inspection support of a rod figured cutting tool are developed. As is well known, the visual inspection of a cutting tool by image processing is not easy, because cutting blade have a helical blade structure. To cope with the problem, an experimental facility with rotation and longitudinal tool shift functions to enable acquisition of blade surface pictures along a cutting rod is developed. The type of the defect treated in this paper is the spot of coating on blade surface. To judge the quality of the processed image of blade surface, neural network with autonomous learning is used. The processed image of cutting tool is divided into 64 ~ 64 blocks used for the
input to the neural networks. Before input, each block data is preprocessed applying a edge detection filter and a transformation by the discrete fourier transform (DFT). Using these technologies, the experimental inspection system is built and tested to check the capabilities of the inspection algorithms. The diagnostic performance of the surface defect of a cutting tool was confirmed. There remained a problem to mis judge the normal tools as the defect.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Human Interface Technology for Operation Support of LargeSized Crane6174ENMaoKawamuraMasamiKonishiKatukiYamagataKoichiShimomura10.18926/17843In this research, a Human Interface system is designed intended to mobile crane. The intervention of human is unavoidable to attain the high performance of electro mechanical system. As is known, crane operation is complicated. Recently, the decrease of expert person induced crane accident. So in near future, it is required a partial automation of crane operation and human support technology. We are aiming at the development of the operation support system for a crane. In this research, development of the hydro mechanical models representing both of static and dynamics movements are made. Further, actual experimental data of operating mobile crane, which are electrical signal data and three-dimension (3D) position of moving load is measured. The actual operating data are compared with the model and it is found that the developed electromechanical model can explain the behaviors of actual data.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Human Support Agent for Design and Diagnosis using Classifier System7592ENKeitaOheMasamiKonishiJunImai10.18926/17844As is well known, an advanced knowledge and know-how are needed in the design and the diagnosis work. Further, human experts can cope with the recent trend of customers
needs. Therefore, the design and the diagnosis work have been privately performed in the past, and its information cannot be shared. In addition, the number of experts is decreasing. It is a very important problem to maintain and to extend experts technologies having been built up. For the purpose, methods and systems for technical inheritance of the advanced techniques of the skilled engineers are needed to train the unskilled operators and also can assist skilled operators. In this research, attention is focused on the design of analog filter circuit. To attain the target, the circuit structural classifier system to support design work is developed. Furthermore, simulation technology for hot strip rolling mills based on distributed agents is presented aimed to develop tools for the diagnosis of hot strip rolling mills operation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Predictor Order and Error Distribution of MMAE Predictors for Lossless Image Coding9398ENHirokazuUenoYoshitakaMorikawa10.18926/17847This paper investigates the relation between error distribution and predictive order of minimum mean abusolute error predictors (MMAE predictors) designed for lossless coding of grayscale images. Design of MMAE predictors reduces to the linear programming problem. Let k be the number of coefficients in a predictor (predictor order), we imagine that predictor order k may have a distribution shaping effect. Main purpose of this paper is to ensure that k has such an effect.No potential conflict of interest relevant to this article was reported.