Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991A Basic Study on Nonlinear Sound Propagation by Finite Element Simulation6980ENYukioKagawaA 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-β 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 Okayama0475-00712621992A Beam Focusing Antenna for the TE(0)n Mode High-Power Millimeter Wave7792ENOsamiWadaThis 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 Okayama0475-00712321989A Design Method for Pin Holding Type Jig919ENHirokazuOsakiMasaakiMatsudaMulti-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 Okayama0475-00713722003A Fast Implementation of Elliptic Curve Cryptosystem with Prime Order Defined over F(p8)7387ENYasuyukiNogamiYoshitakaMorikawaPublic key cryptosystem has many uses, such as to sign digitally, to realize electronic commerce. Especially, RSA public key cryptosystem has been the most widely used, but its key for ensuring sufficient security reaches about 2000 bits long. On the other hand, elliptic curve cryptosystem(ECC) has the same security level with about 7-fold smaller length key. Accordingly, ECC has been received much attention and implemented on various processors even with scarce computation resources. In this paper, we deal with an elliptic curve which is defined over extension field F(p2c) and has a prime order, where p is the characteristic and c is a non negative integer. In order to realize a fast software implementation of ECC adopting such an elliptic curve, a fast implementation method of definition field F(p2c) especially F(p8) is proposed by using a technique called successive extension. First, five fast implementation methods of base field F(p2) are introduced. In each base field implementation, calculation costs of F(p2)-arithmetic operations are evaluated by counting the numbers of F(p)-arithmetic operations. Next, a successive extension method which adopts a polynomial basis and a binomial as the modular polynomial is proposed with comparing to a conventional method. Finally, we choose two prime numbers as the characteristic, and consider several implementations for definition field F(p8) by using five base fields and two successive extension methods. Then, one of these implementations is especially selected and implemented on Toshiba 32-bit micro controller TMP94C251(20MHz) by using C language. By evaluating calculation times with comparing to previous works, we conclude that proposed method can achieve a fast implementation of ECC with a prime order.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 Canceling207212ENToruNakanishiIn 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 Okayama1349-6115432009A High-Speed Square Root Algorithm for Extension fields -Especially for Fast Extension Fields-99107ENHidehiroKatoYasuyukiNogamiYoshitakaMorikawaA square root (SQRT) algorithm in extension field F(p(m))(m = r(0)r(1)･･･r(n−1)･2(d), r(i) : odd prime, d : positive integer) is proposed in this paper. First, a conventional SQRT algorithm, the Tonelli-Shanks algorithm, is modified to compute the inverse SQRT in F(p(2d)), where most of the computations are performed in the corresponding subfields F(p(2i)) for 0 ≤ i ≤ d-1. Then the Frobenius mappings with addition chain are adopted for the proposed SQRT algorithm, in which a lot of computations in a given extension field F(p(m)) are also reduced to those in a proper subfield by the norm computations. Those reductions of the field degree increase efficiency in the SQRT implementation. The Tonelli-Shanks algorithm and the proposed algorithm in F(p(6)) and F(p(10)) were implemented on a Core2 (2.66 GHz) using the C++ programming language. The computer simulations showed that, on average, the proposed algorithm accelerated the SQRT computation by 6 times in F(p(6)), and by 10 times in F(p(10)), compared to the Tonelli-Shanks algorithm.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 Cryptosystem8292ENFengWangYasuyukiNogamiYoshitakaMorikawaIn 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 Okayama0475-00713011995A Logical Problem Decomposing Method for Decision Makers917ENHirokazuOsakiDecision 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 Okayama0475-00714212008A Method for Checking the Parity of (#Jc - 1)=2 of Genus 2 and 3 Hyperelliptic Curves110114ENYasuyukiNogamiYoshitakaMorikawaThis 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 Okayama0475-0071351-22001A Method for Design Production System with Multi Energy Resources183189ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaThis 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 Okayama0475-00713311998A Method for Designing an Automatic Monitoring System for Unmanned Rooms5357ENHirokazuOsakiYasuhiroKajiharaYosiomiMunesawaA 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 π/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 Okayama0475-00712921995A Method for Designing the Supplying Method of Parts to an Assembly Line1321ENHirokazuOsakiYasuhiroKajiharaWe 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 Okayama0475-00713912005A Method for Generating Prime Order Elliptic Curves over F(q(2c))7181ENYasuyukiNogamiYoshitakaMorikawaThis 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 Okayama0475-00713011995A Method for Standardizing Parts with Integer Programming17ENYasuhiroKajiharaHirokazuOsakiYoshiomiMunesawaA 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 Okayama0475-00712511990A Method of Cubic Object Feature Extraction113ENTsutomuWadaToshiroNoritsuguHow 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 Okayama0475-00713121997A Method of Shape Recognition Using Geometry Information6165ENHirokazuOsakiAt present, the two dimensional CAD systems which are used to make drawings go around widely. But in order to use design data at the lower stream of production process, the replacement from the two dimensional CAD systems to the three dimensional CAD systems have started. Accordingly it is dimensional drawings for the three dimensional shapes. And it is also necessary to store them in the three dimensional CAD systems. And in the studying of the machine vision which is often used as "Eyes of robot" , it is being studied the method to recognize the three dimensional objects from the two dimensional image. This is the problem about data exchange, too. Therefore in this report, we propose the method to exchange the plural two dimensional elements of figure from image relations between elements were found from reference of the element coordinates. Next, the three dimensional shapes were reasoned from reference of the knowledge (for corner, etc) prepared beforehand. Then that data were exchanged to the three dimensional CAD data. We report one example about this method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999A Method of Shape Recognition Using CAD Data and Vertex-Dictionary8589ENMitsuruYamadaHirokazuOsakiWe reason the circumstances around the three-dimensional vertex from the information about the intersection point in the two-dimensional image data inputted from a camera on the premise that we use this method as the eye ot the robot. In this method, we use the Vertex-Dictionary. We make the Vertex-Dictionary by calculation from CAD data of object figure (these data are already known) and the position data of the point of view. This dictionary includes the data of position and relations of connect surface etc. about a vertex. We get the data of three-dimensional vertex by comparison the data of two-dimensional intersection point in image data and Vertex-Dictionary. And we get the three-dimensional object by reasoning about the information of circumstances of all vertexes. Then we can recognize the three-dimensional object from image data. In this report, we explain the process to calculate the Vertex-Dictionary and some examples about this method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713321999A Numerical Study on the Performance of an Open-type Flat-plate Solar Collector2537ENHideoInabaAkihikoHoribeA set mathematical models was developed for predicting the performance of an open-type flat-plate solar collector, and solved numerically through an implicit difference method. The effects of various parameters on the absorption of solar energy for the collector were investigated. The results showed that the solar energy absorptance of the open-type flat-plate collector was relatively high especially for the region where the weather was humid and hot, and there were an optimum length and an optimum tilt angle for the absorbing plate on which the collector could obtain the highest solar energy absorptance. It was found that the latent heat flux of water evaporation could be 5 to 15 times larger than the sensible heat flux. The effects of the magnitude of the solar incident flux, the atmospheric humidity, the atmospheric temperature, the absorbing plate tilt angle, and water film thickness on the temperature rising of the water film were clarified in numerical quantities. The increase of the solar incident flux, the atmospheric humidity or the atmospheric temperature also resulted in a rise in the energy absorptance of the collector.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712521991A Procedure for Settling Multi-Criteria Problem by a Small Group of Decision Makers5567ENYoshimasaKameyamaHayatoshiSayamaKazuhikoSuzukiAHP can handle decision-making problems involving several criteria when some of these are difficult or impossible to compare other than numerically. When a small group of decision makers settle the multi-criteria problem by AHP, the members of group could not often reach an agreement with hierarchic structure involving objectives, criteria, sub-criteria and alternatives because they have different
positions, interests, and opinions. Further, the members have different importances for criteria and sub-criteria, and have dissimilar preferences for alternatives. In this article, we reveal the troubleness of AHP in case of being used by a small group of decision makers. Moreover, we proposed a procedure of AHP which the members of group could easily agree with the structure of problem and the weights of criteria etc.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 Lidar93101ENKengoIokibeYoshitakaToyotaOsamiWadaRyujiKogaThe 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 Okayama0475-00712811993A Simple Method to Evaluate Structural Stability of Group IV and III-V Semiconductors125ENShigetoshiNaraHirooTotsujiThe 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 Okayama0475-00712811993A Simple Model for Hydrogen-Bonding Ferroelectrics3950ENChiekoTotsujiThere 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 Okayama0475-00713021996A Simple Model for Oxygen Conduction in Some Perovskite Compounds3943ENChiekoTotsujiA 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 Okayama0475-00713321999A Study of Facility Layout Method in Recycling Plant using AGV111119ENYoshiomiMunesawaHirokazuOsakiOur 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 Okayama0475-00713311998A Study on Robot System to Hand Surgical Intrument to a Surgeon in a Surgery (1st Report, Development of Surgical Instrument Recognition System)3137ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaShujiSekiThe 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 Okayama0475-00712821994A Study on the Elasto-plastical Constitutive Equation for Unsaturated Soil5975ENMakotoNishigakiIichiroKohnoIn this paper, first, an elasto-plastic consitituve equation for unsaturated soil was developed by considering of the basically behavior of unsaturated soil. Second, the results of a number of triaxial test and a set of rigid
foundation model tests were simulated by using this constitutive equation, the agreement between observed and computed results was satisfactory and confirms the possibilities of this constitutive equation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713622002A Study on the Planning and Scheduling of Production System Considering Demand Changes1542ENRyujiOhtaniMasamiKonishiJunImaiTatsushiNishiIn this paper, we studied a planning and scheduling of production system considering demand changes. In the proposed system, planning part determines lot-size and amount of jobs in production. On the other hand, scheduling part determines the production sequence of jobs. In order to treat with the demand changes, both planning and scheduling should work well simultaneously. In the proposed system, preset and real time production control system is newly constructed from the view point of adaptive control. In the system, production planning is modified when the difference between production amount and demand becomes large. Moreover, production schedule is regenerated when the determined schedule is deviated from the prospected one. The scheduling system is characterized as the autonomous decentralized optimization system where each job works as agent and agent searches its appropriate starting time of processing. The effectiveness of the proposed system is confirmed by numerical examples.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 Programs97135ENSusumuYamasakiYoshinoriKuroseIn 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 Okayama0475-00713321999Acousticmyogram Measured with Electrosimulation During Muscle Fatigue3944ENHisaoOkaThe acousicmyogram (AMG) is a mechanical phenomenon recorded at the surface of an active muscle. It is used to monitor force production, fatigue, and contractile properties of muscle. In this study, the new electrode with accelerometer for electrostimulation and acoustic detection. It consists of Ag-AgCl active electrode and solid-gel annular groud, and a very light piezoresistive accelerometer. The recorded AMG waveform depends on the pulse amplitude and duration of stimulation current and its lag from the electroatimulation is about 7 ms. The strengh-duration (S-D) curve (the threshold current for stimulation vs. pulse duration) describes the excitability of muscle. The left forearm is electrostimulated by using the same electrode and the muscle vibration (AMG) is recorded with accelerometer. During the muscle fatigue, the S-D curve changes and the current threshold increases under the same pulse duration. The rheobase of S-D curve increases gradually but the chronaxie hardly changes during muscle fatigue.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712711992Advection Dispersion by Eulerian Lagrangian Finite Element Method93105ENMakotoNishigakiIchiroKohnoIn this paper the author will be describe phenomena of advection dispersion in subsurface flow by using Eulerian Lagrangian Finite Element Method. Where Finite Element Method with Galerkin formulation and weigthed residual method is used to solve seepage and advection dispersion equation. The problem of one dimensional and two dimensional rectangular wave are analyzed in this paper. And the result of numerical analyses will be compared with analytical solutions. The numerical results showed the very good agreement with the analytical solutions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713722003Aerosol Extinction Coefficient Continuously Measured with Polarized Mie Scattering Lidar8997ENKengoIokibeYoshitakaToyotaOsamiWadaRyujiKogaAerosol extinction coefficients of clouds and dust were continuously measured in the year of 2002 with a polarized Mie-scattering lidar controlled by an automatic and remotely operating system utilizing internet services. Measured cloud extinctions were greater than 1.0 km(-1) below the altitude 6 km, 0.17 - 1.0 km(-1) between 6 and 10 km, and 0.091 - 0.3 km(-1) beyond 10km. Extinction of dust were 0.10 and 0.20 km(-1) for Asian dust and 0.057 km(-1) for urban dust.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-SehaimMasamiKonishiKazuoNoseIn 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 Okayama0475-00713712002Agent Based Routing Control for Multi Mobile Robots in Transportation110ENKenSotobayashiMasamiKonishiTatsushiNishiJunImaiAuto Guided Vehicles (AGVs) are widely used in a semi-conductor fabricating factory and contribute to the stable production of a high quality semi-conductor products. In the near future, further expansion of the transportation system is expected accompanied with the rapid growth of semi-conductor industries. In such situation, the necessity of performing quick planning of transportation route and transportation control will be elevated. In this paper, practicable planning of the transportation route and transportation control are studied based on the decentralized agent method. Especially, the geometrical sizes of AGVs are considered in the determination of transportation routes and control strategy avoiding the occurrence of mutual collisions or deadlock of AGVs.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Aging in Dilute Al-Si Alloys1116ENAkiraSakakibaraTerutoKanadaniAging 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 Okayama0475-0071351-22001Alkenylation and Allylation of Aldehydes by Using an Ni/Cr/TDAE Redox System4146ENManabuKuroboshiMuneakiTanakaSuguruKishimotoKentaroGotoHideoTanakaIn 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 Okayama0475-00712311988Amorphous Oxides Prepared from Organometallic Compounds Part 1. Preparation of Sodium Borosilicate Gels3138ENYoshinariMiuraAkiyoshiOsakaKatsuakiTakahashiSodium borosilicate gels of compositions similar to that of Vycor(R) glass like 80SiO(2).15B(2)O(3).5Na(2)O(wt%) were prepared from hydrolysis and polycondensation of tetraethyl orthosilicate, trimethyl borate, and sodium methylate under the HCl catalysis. Variation of the gelation time is examined as a function of the mixing ratio of the starting materials and the catalyst. The thermal behavior of the gels has been discussed on the basis of their TG and DTA traces.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712311988Amorphous Oxides Prepared from Organometallic Compounds Part2. Structure Evolution in Sodium Borosilicate Gels3948ENAkiyoshiOsakaYoshinariMiuraKatsuakiTakahashiSodium borosilicate gels of compositions similar to that of Vycor(R) glass like 80SiO(2).15B(2)O(3).5Na(2)O (wt%) were prepared from hydrolysis and polycondensation of metal alkoxides under the HCl catalysis. Variation of specific surface area and porosity with temperature indicated that closed pores were opened below 400℃, and collapsed above 450℃ after the porosity reached a maximum value around 450℃. The structural evolution was examined due to IR spectra and a phase separation in the gels was observed. The solubility of the gels into 1N-HCl was studied as a function of the treatment temperature.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 Field1119ENYasuyukiNogamiYoshitakaMorikawaThis 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 Okayama0475-00713321999An Analytical Method of Human Motion by Image Processing105110ENHirokazuOsakiThis paper deals with analytical method of human motion by image processing to make a model of the scooping process, Firstly, the scooping tool is the spoon, and while the scooping process is performing, the movement of the mouth center position and the spoon top position are measured by two cameras. As the amount of substance is over the uppermost area of the cup, the spoon is stuck obliquely into substance. Then the spoon is rotated and lifted up to the mouth. Secondly, we recognize the mouth center from the characteristic of the face image data and calculate the spoon top position to extract two points on the spoon handle from the time series images by two cameras. Finally, we describe the method of recognizing the coordinate of the mouth center and estimating the coordinate of the spoon top to analyse the scooping process.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 Trips2132ENDiversion 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 Okayama0475-0071221988An Experimental Study on Levee Failure Caused by Seepage and Preventive Measures4562ENIichiroKohnoMakotoNishigakiYujiTakeshitaThere are two classifications of the mechanism of levee failure caused by floods; local seepage failure and progressive failure. The fundamental causes of levee failure produced by piping and erosion were studied and the safety of river leves during floods evaluated in terms of soil machanics. The critical hydraulic gradient and the process of progressive failure were obtained from one- and two- dimensional model experiments for piping and erosion. Problems inherent in and preventive measures against levee failure are discussed. In particular, effects of the Tsukinowa method, the most representative Japanese flood fighting method, were studied experimentally and improvements proposed.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 Assembly19ENYasuhiroKajiharaHirokazuOsakiPrecedence 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 Okayama0475-00712921995An Expert System for Reducing the Variety of Parts in Multi-item Production2327ENYasuhiroKajiharaHirokazuOsakiA 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 Okayama0475-00712411989An Expert System for the Scheduling of a Flexible Assembly Line for Multi Item Products2539ENYasuhiroKajiharaHirokazuOsakiAn 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 Okayama0475-00714012006An Eye-Contour Extraction Algorithm from Face Image using
Deformable Template Matching7882ENNobuoFunabikiMegumiIsogaiTeruoHigashinoA variety of studies on face components such as eyes, lips, noses, and teeth have been proceeding in medicine, psychology, biometrics authentication, and other areas. In this paper, we present an algorithm of extracting eye contours from a face image using the deformable template matching method. Our template for an eye contour is composed of three quadratic functions for the perimeter and one circle for the pupil. In our algorithm, a digital color face image is rst converted to a binary image of representing eyes, after the region around eyes is identied on the face image by using hues and values of the color
image. Then, parameters in the template are optimized by a local search method with a tabu period and a hill-climbing, so as to t the template to the eye contour in the binary
image. The accuracy of our algorithm is evaluated through sample face images of students.
In addition, the application of our proposal to eye shape indices is investigated in a face image database "HOIP", where recognizable dierence exists in index distributions between males and females.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 Container169175ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaWe 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 Okayama0475-00713021996Analysis of Quantum Waveguide : Effective Width and Height of Potential for Quantum Wires under Split Gates2125ENHirooTotsujiIn 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 Okayama0475-00712521991Analysis of Superconducting Microstructures: Critical Temperature of Two-Dimensional Structures95113ENHirooTotsujiCritical 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 Okayama0475-00712521991Analysis of Superconducting Microstructures: Formulation8193ENHirooTotsujiNumerical 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 Okayama0475-00712411989Analysis of the Radiation Characteristics of a Primary-Feed Waveguide in a Quasi-Optical Antenna for Circular TE(On) Mode8192ENOsamiWadaAre 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 Okayama0475-00713321999Apatite Formation on Electrochemically Treated Titanium7984ENAkiyoshiOsakaSatoshiHayakawaKanjiTsuruA 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 Okayama0475-00713612001Application of Dead Beat Control method to the Water Level Control of Small-scale Hydroelectric Power Plant1728ENShinichiroEndoMasamiKonishiSmall Scale Hydroelectric Power Generation is made using the water drop caused by the gradient difference between that of the river and that of the penstock. The water flow in this system apt to vary with time. Especially, at the time of the flood or that of the dry, the flow in the water stream varies largely. To realize the stable generation, it is necessary to maintain the water level in the head tank located in the mid way in the stream channel at a constant level. In this paper, variation of water level is forecasted using two-tank model for the penstock and the head tank and the water level control algorithm is proposed by deadbeat control. The effectiveness of the algorithm is evaluated beforehand using the simulation program of the water environment for the hydroelectric generation system.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 System2127ENTakashiTorigoeMasamiKonishiJunImaiTatsushiNishiIn 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 Furnace2839ENKazuhitoIshimaruMasamiKonishiJunImaiTatsushiNishiIn 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 Okayama0475-00713622002Application of Transfer Matrix Method with Signal Flow-Chart to Analyze Optical Multi-Path Ring-Resonator7382ENIip SyarifHidayatYoshitakaToyotaOsamuTorigoeOsamiWadaRyujiKogaA multi-path ring-resonator (MPRR) was proposed to extend FSR of ring resonator. However, it is complicated to analyze the MPRR by using well-known analysis techniques such as scattering matrix or other numerical methods. This paper describes procedure for deriving transfer matrix by means of signal flow-chart to analyze the MPRR. We do not need complicated calculation for steady state analysis because transfer matrix elements are formulated clearly. As a result, The calcultaion time in this method can be reduced 1/3 to 1/20 times compared with using scattering matirx method. Furthermore, a transmittance characteristics of the MPRR at FSR extension-factor of 10 will also be shown. This suggests that analysis of other types of the MPRR by using this method can be performed simply and take a shorter time.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Application of the Adjoint Spectrum to the Frequency Tracking in Spectrometry with Tunable Diode Lasers Suffering from Temperature Drift4349ENMoncefBouzidiRyujiKogaOsamiWadaNaokiKagawaMegumiKosakaA numerical technique called as "adjoint spectrum" has been proposed by the authors in a previous work. Two applications of it are presented here. It is demonstrated that by generalizing the aspect of adjoint spectrum it becomes possible to measure densities of mixed gases simultaneously. An experimental proof of this has been carried on and simultaneous measurement of densities of both methane and dinitrogen oxide was realized. On the other hand, it is also reported that frequency shifting of spectra, which is a cause of error in spectrometric measurements, can be corrected by exploiting the adjoint spectrum technique in connection with the Taylor expansion. Numerical examples showing the success of this method are reported as well.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713712002Automatic Camera Model Selection for Multibody Motion Segmentation4149ENYasuyukiSugayaKenichiKanataniWe study the problem of segmenting independently moving objects in a video sequence. Several algorithms exist for classifying the trajectories of the feature points into independent motions, but the performance depends on the validity of the underlying camera imaging model. In this paper, we present a scheme for automatically selecting the best model using the geometric AIC before the segmentation stage, Using real video sequences,
we confirm that the segmentation accuracy indeed improves if the segmentation is based on the selected model. We also show that the trajectory data can be compressed into low-dimensional vectors using the selected model. This is very effective in reducing the computation time for a long video sequence.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713612001Automatic Detection of Circular Objects by Ellipse Growing107116ENKenichiKanataniNaoyaOhtaWe present a new method for automatically detecting circular objects in images: we detect an osculating circle to an elliptic arc using a Hough transform, iteratively deforming it into an ellipse, removing outlier pixels, and searching for a separate edge. The voting space is restricted to one and two dimensions for efficiency, and special weighting schemes are
introduced to enhance the accuracy. We demonstrate the effectiveness of our method using real images. Finally, we apply our method to the calibration of a turntable for 3-D object shape reconstruction.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 Times8994ENKenjiSekoguchiShigejiMiyazakiThe 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 Okayama0475-00712421990Basic Characteristics of Microvibration on the Skin Surface3140ENHisaoOkaTatsumaYamamotoA small vibration on the body surface is expected to apply to a clinical examination of the autonomic nervous system. The vibration cannot be found by the naked eyes. It is called a microvibration (MV) or a minor tremor (MT). It is not cleared out why and how the MV occurs, but many papers about its occurrence and clinical application have been published. In this study, the typical spectrum of MV and the various causes of MV occurrence are studied. The relationships of MV with heart rate, muscle contraction and MV are discussed. The power spectrum of MV is obtained by using an autoregressive model.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Bioactive Calcium Borosilicate Glasses for Enameling Titanium4551ENAkiyoshiOsakaSatoshiHayakawaChikaraOhtsukiThe 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 740℃ 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 Okayama0475-00713121997Bioactivity of Nb(V) and Ta(V)-Doped Calcium Silicate Glasses3944ENSatoshiHayakawaChikaraOhtsukiAkiyoshiOsakaNb(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 Okayama1349-6115452011Bundle Adjustment for 3-D Reconstruction: Implementation and Evaluation2735ENKenichiKanataniYasuyukiSugayaWe describe in detail the algorithm of bundle adjustment for 3-D reconstruction from multiple
images based on our latest research results. The main focus of this paper is on the handling of camera rotations and the efficiency of computation and memory usage when the number of variables is very large; an appropriate consideration of this is the core of the implementation of bundle adjustment. Computing the fundamental matrix from two views and reconstructing the 3-D structure from multiple views, we evaluate the performance of our algorithm and discuses technical issues of bundle adjustment implementation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115462012Calibration of Ultra-Wide Fisheye Lens Cameras by Eigenvalue Minimization1020ENKenichiKanataniWe present a new technique for calibrating ultra-wide fisheye lens cameras by imposing the constraint that collinear points be rectified to be collinear, parallel lines to be parallel, and orthogonal lines to be orthogonal. Exploiting the fact that line fitting reduces to an eigenvalue problem, we do a rigorous perturbation analysis to obtain a Levenberg-Marquardt procedure for the optimization. Doing experiments, we point out that spurious solutions exist if collinearity and parallelism alone are imposed. Our technique has many desirable properties. For example, no metric information is required about the reference pattern or the camera position, and separate stripe patterns can be displayed on a video screen to generate a virtual grid, eliminating the grid point extraction processing.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 Nets4965ENChujiMoriDistance 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 Okayama0475-0071351-22001Characteristics of a Monoacylglycerol Lipase Isolated from Pseudomonas sp. LP7315 -Hydrolysis and Synthesis of Monoglycerides137146ENTakaharuSakiyamaTsuyoshiYoshimiAkiraMiyakeMidoriUmeokaAtsushiTanakaShoOzakiKazuhiroNakanishiA 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 65℃. The hydrolytic activity depended not only on temperature and pH but also on the type of monoglyceride used. MGL also catalyzed monoglyceride synthesis at 65℃ 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 Okayama0475-00712821994Chemical States of Fluorine Atoms and Laser-Induced Crystallization in rf-Sputtered Thin Films of Amorphous Lead Fluorosilicate7784ENAkiyoshiOsakaYoshinariMiuraAmorphous films of lead oxyfluorosilicate were prepared with a rf-sputtering technique, and the distribution profiles of the component elements and chemical states of the fluoride ions were analyzed with an X-ray photoelectron spectrometer. Si atoms with an expanded coordination, O(4)Si-F, were present near the surface, and O(3)Si-F units were present in the deeper part of the films. Electrical resistance indicated transition to a
conduction state for the films containing fluoride ions, while the films were crystallized to precipitate low quartz by the irradiation of He-Ne laser of 3 mW up to 1 sec.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.YokotaThe 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 Okayama0475-00712821994Collimation of Cerenkov-SHG Blue Light with a Parabolic Mirror3344ENMingWangAnisAhmedOsamiWadaRyujiKogaProposed 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 0.07λ. By using an objective lens, the collimated beam can be focused down to a thin beam with the spot size less than 1μm.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071381-22004Combinatorial Boundary Tracking of a 3D Lattice Point Set7389ENYukikoKenmochiAtsushiImiyaBoundary tracking and surface generation are ones of main topological topics for three-dimensional digital image analysis. However, there is no adequate theory to make relations between these different topological properties in a completely discrete way. In this paper, we present a new boundary tracking algorithm which gives not only a set of border points but also the surface structures by using the concepts of combinatorial/algebraic topologies. We also show that our boundary becomes a triangulation of border points (in the sense of general topology), that is, we clarify relations between border points and their surface structures.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071321-21998Comparative Considerations of Eliminating Method for Power Line Interference in Electrocardiography714ENYoshitakeYamamotoThis paper describes a new measurment method and principle of power line interference elimination in ECG signal using inverse loop and AC power line configuration (APC). First, we considered that magnetic induction effect not only depend on a conductive loop area that formed by shielded wires that connect the object and amplifier but also effect of body area effective must be considered. It is simple and useful because interference can be eliminated to very small value show that the condition and it can be applied in a real ECG signal recording. Second, results show that the contribution of displacement currents into the object especially APC in vertical configuration is smaller than it in other one. Because this method is so easy that it is convenient to be used to understand some aspects of power line interference elimination phenomenon. Hence we expect that this method can be used as one of improvement method in measurement system of ECG signal recording.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 Network1940ENShigetoshiNaraHirooTotsujiNumerical 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 Okayama1349-6115472013ContentsENFaculty of Engineering, Okayama UniversityNo potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115462012ContentsENFaculty of Engineering, Okayama UniversityNo 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 Okayama0475-0071381-22004Control Method for Temperature Distribution in Reactor Furnace by Sequential Quadratic Programming Method514ENKazuhitoIshimaruMasamiKonishiJunImaiTatsushiNishiTemperature distribution in the reactor furnace is mainly operated by gas blowing from multiple tuyeres and material charge distribution. The objective of our research is obtain the optimal profile of gas flow to control temperature distribution in the reactor furnace in the shortest possible time. We formulated the optimization problem to reduce deviation of temperature distribution from its desired one in the reactor furnace. Based on the formulation, gas blow conditions are optimized by a sequential quadratic programming method to realize the desired temperature distribution. The validity of the method was checked through numerical experiments.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 Effect4147ENHirooTotsujiA 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 Okayama0475-00714212008Cooperation of Production, Product Handling and TransferScheduling for Semiconductor Fabrication91103ENHamanaRyoheiMasamiKonishiJunImaiVarious 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 Okayama0475-0071351-22001Cooperative Handling Robot with Human Beings177182ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaThe 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 Okayama0475-00712921995Correction of Apparent Viscoelasticity of Skin Surface3947ENHisaoOkaShun-yaSakamotoThe body structures under the skin surface, such as bones and tendon, have an influence on the stiffness evaluation observed from the surface. In this case, the observed stiffness should be called an apparent stiffness. To obtain the biomechanical properties of skin itself, the influence of body structure should be removed. This study deals with the correction method of apparent viscoelasticity which calculated from apparent biomechanical impedance. This method is applied to the measured result of the forearm and the right chest to confirm its effectiveness.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Cost Evaluation of The Improvement of Twisted Ate Pairing That Uses Integer Variable X of Small Hamming Weight113116ENYumiSakemihidehiroKatoYasuyukiNogamiYoshikawaMorikawaBarreto–Naehrig (BN) curve has been introduced as an efficient pairing-friendly elliptic curve over prime field F(p) whose embedding degree is 12. The characteristic and Frobenius trace are given as polynomials of integer variable X. The authors proposed an improvement of Miller's algorithm of twisted Ate pairing with BN curve by applying X of small hamming weight in ITC–CSCC2008; however, its cost evaluation has not been explicitly shown. This paper shows the detail of the cost evaluation.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 films17ENKenichiShimizuTashiyukiToriiKokiIshidaUsing 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 100μm and those reduced the thickness from the 100μm to 50μm 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 100μm, while the fatigue crack propagated faster in the film with the thickness of 50μm than that with the thickness of 100μm regardless of the small crystal rotation angles with the fatigue testing for the film with the thickness of 50μm.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 Cylinder2131ENKyojiYamamotoAn 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 Okayama0475-0071341-22000Cytocompatibility of Silicone Elastomer Treated with Hydrogenperoxide Containing Tantalum Chloride3943ENSatoshiHayakawaYukiShirosakiTakeshiYabutaKanjiTsuruAkiyoshiOsakaSilicone elastomer was chemically treated at 60℃ 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 36.5℃ 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 Okayama0475-00713622002Cytotoxicity of the Bacillus thuringiensis Crystal Protein against Mammalian Cells6166ENMasashiYamagiwaAkitoshiNambaTetsuyukiAkaoEiichiMizukiMichioOhbaHiroshiSakaiThe crystal proteins produced by Bacillus thuringiensis subsp, israelensis (Bti) and subsp. coreanensis A1519 strain were examined for the cytotoxicity against MOLT-4 and HeLa cells by MTT assay and LDH assay, The A1519 crystal proteins processed by proteinase K exhibited the specific cell-killing activity toward MOLT-4 with little damage to the cell membrane, On the other hand, the Bti crystal proteins processed by proteinase K caused the substantial damage to the cell membrane of both MOLT-4 and HeLa, leading to the cell lysis. The non-digested crystal proteins of both strains exhibited no cytotoxicity, These data suggested that while the Bti crystal proteins caused the colloid-osmotic swelling and cell lysis of MOLT-4 and HeLa, the proteinase K-digested A1519 crystal proteins induced the specific cell death of MOLT-4 through a mechanism other than that of Bti.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 Problem4451ENRyotaMaenoMasamiKonishiJunImaiPetri 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 Dijkstra’s 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 Okayama0475-00713321999Density Functional Molecular Dynamics of Hydrogen Plasma5159ENHirooTotsujiKenjiTsurutaChiekoTotsujiDensity functional molecular dynamics method is applied to hydrogen plasma in the domain of liquid metallic hydrogen. Tentative results for the proton-proton pair distribution function and the electron-proton pair distribution function are obtained. It is shown that with the increase of the parameter γ(s), we have increasingly strong screening of proton charge by electrons and the decrease of electron density in the domain between protons.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 19982737ENHeWeiRyujiKogaKengoIokibeOsamiWadaYoshitakaToyotaIn 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 Okayama0475-00712721993Design of Hump Profile in Railroad Classification Yard4158ENThe 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 Okayama0475-00712721993Design of an Adaptive Observer to Estimate Unknown Periodical Disturbances7385ENAkiraInoueShiroMasudaThis 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 Okayama0475-00712811993Determination of Clay Minerals by the Ignition Loss Method
Using a Muffle Furnace5159ENIichiroKohnoA 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 530℃ and 800℃ 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 Okayama0475-00712311988Determination of Electrical Parameters for Skin during Galvanic Skin Reflex from Continuous Measurement6168ENYoshitakeYamamotoTatsumaYamamotoSkin 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 Okayama0475-00712411989Determination of Unsaturated Soil Hydraulic Properties by Transient Flow Experiments and Parameter Estimation107114ENIichiroKohnoMakotoNishigakiYujiTakeshitaThe numerical feasibility of determining soil water retention and hydraulic conductivity functions simultaneously from one-dimensional transient flow experiments in the laboratory by parameter estimation method is evaluated. Soil hydraulic properties are assumed to be represented by van Genuchten's closed-form expressions involving two unknown parameters: coefficients α and n . These parameters are evaluated by nonlinear least-squares fitting of predicted and observed pressure head with time. Gravity drainage experiments are performed for Toyoura standard sand to evaluate the adequacy of this proposed method.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712511990Determining Hydraulic Properties of Multilayered Aquifers from Pumping Test Data by Parameter Estimation99109ENMakotoNishigakiYujiTakeshitaIichiroKonoIn this paper, a numerical procedure of determining hydraulic properties in multilayered aquifers are presented. From pumping test data in multilayered aquifers, the coefficient of permeability and specific storage for each aquifer are determined by using a combination of finite element analysis and nonlinear least-squares optimization technique. This study especially points out necessity of stress-flow coupling analysis to explain the behaviors of pressure head in multilayered aquifer during pumping test. As a example, practical pumping test data were evaluate and the coefficients of permeability and specific storage of aquifers and aquitard were obtained.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 Traces197205ENYasuyukiNogamiYoshitakaMorikawaModern 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 Okayama0475-0071351-22001Development of Assembly Robot System for Flexible Belt-Shaped Subject163168ENHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaWe 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 Okayama0475-0071351-22001Diagnostic method for induction motor using simplified motor simulator4751ENYukihiroDoumaeMasamiKonishiJunImaiHidekiAsadaAkiraKitamuraIn 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 Okayama0475-00712711992Direct Patterning of Ceramic Circuit Board with Q-Switched Nd:YAG Laser110ENYoshiyukiUnoShin-ichiroKubotaToshikatsuNakajimaKojiroOgataNobuhikoTadaDirect 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 Okayama0475-0071351-22001Disassembly System using an Impact Hammer for the Material Recycling191196ENYoshiomiMunesawaHirokazuOsakiYasuhiroKajiharaWe 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 Okayama1349-6115432009Dispersion Models and Electromagnetic FDTD Analyses of
Nanostructured Metamaterials using Parallel Computer815ENChiekoTotsujiKenjiTsurutaHirooTotsujiMetamaterial 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 Okayama0475-00714012006Distribution of Electrons in Quantum Dots Analyzed by Classical Mapping and Molecular Dynamics4043ENMiyakeTakashiChiekoTotsujiKenjiTsurutaHirooTotsujiThe 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 Okayama0475-00712811993Drain System Around the Underground Cavern87128ENIichiroKonoMakotoNishigakiIn recent years, construction or planning of large-scale underground structures, such as underground power plants, underground oil storage plants and nuclear power plants have been coming into consideration in Japan. To construct such as large-scale underground structures, one of the most important problems is to make clear beforehand the behavior of groundwater around these structures and the other is to carry out proper countermeasure of groundwater, so that these structures can be constructed safely and maintained stability over a long time period.
This report describes the results of theoretical studies on the drain systems and at the same time, discusses the drain systems around the underground cavern for the practical underground power stations.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071381-22004Dynamical Properties of Two-Dimensional Yukawa Liquids: A Molecular Dynamics Study3337ENM. SanusiLimanChiekoTotsujiKenjiTsurutaHirooTotsujiThe dynamic structure factor and the spectrum of the momentum-density fluctuations of 2D Yukawa liquids are analyzed in the domain of weak and intermediate coupling and screenlng parameters. The dispersion relations of the longitudinal and transverse collective excitations are obtained and compared with the random phase approximation (RPA) and harmonic approximation for triangular lattice.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115442010Ecient Squaring Algorithm for Xate Pairing with Freeman Curve6972ENKentaNekadoHidehiroKatoYasuyukiNogamiYoshitakaMorikawaRecently, pairing–based cryptographies have attracted much attention. For fast pairing calculation, not only pairing algorithms but also arithmetic operations in extension field should be efficient. Especially for final exponentiation included in pairing calculation, squaring is more important than multiplication. This paper proposes an efficient squaring algorithm in extension field for Freeman curve.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712921995Effect of Alcohol on Bioactivity of Glasses8388ENKanjiTsuruChikaraOhtsukiAkiyoshiOsakaOne of the CaO,SiO(2)-based bioactive glasses(5OCaO･ 5OSiO (2) in mol%) were soaked for various periods in a simulated body fluid(SBF) with or without containing alcohols such as methanol, ethanol, and 1-propanol. Effect of the alcohols was investigated on the apatite formation on the glass surface with thin-film X-ray diffraction, FT-IR reflection spectroscopy and scanning electron microscopy. Under the presence of alcohols up to 0.1mol/l in the SBF an apatite layer was formed on the glass, while it consisted of crystallites similar in morphology but
larger in size than that found for the SBF without the alcohols. It was concluded that the alcohols little influenced the the apatite forming ability of the CaO,SiO(2)-based glasses.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713622002Effect of Heat Treatment on the Serration of Low-Concentrated Al-Zn Alloys16ENAkiraSakakibaraTerutoKanadaniTsutomuTashiroKazumiYoshiokaThe effect of heat-treatment conditions on occurrence of serration in Al-Zn alloys was investigated. Specimens were aged for various times up to 2.6Ms at 293K or 273K after quenching from various temperatures (T(Q)), 473K to 853K, and tensile-tested at room temperature. Serration occurred more easily according as T(Q) became lower and the aging time became shorter: in the case that T(Q)=473K serration was observed even after aging for 2.6Ms, while in the case that T(Q)=773K serration did not occur irrespective of aging conditions. Serration was also recognized when the specimens were furnace-cooled from 773K to room temperature. These results together with those obtained by the electrical resistometry suggest that the serration in the low'concentrated Al-Zn alloy is caused by the formation of small GP zones whose Guinier radius is less than 1nm or some sort of solute clusters.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 Alloy1521ENAkiraSakakibaraTerutoKanadaniAging 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 Okayama0475-00713311998Effect of Solute Clusters on Low Temperature Aging in Dilute Al-Ag Alloys14ENAkiraSakakibaraTerutoKanadaniAging of diolute Al-Ag alloys after quenching from low temperatures were studied mainly by electrical resistometry. Maximum resistivity observed in the aging curve of specimens quenched from high temeperature disappeared when the quenching temperature was lowered to 473 or 453K. When the quenching temperature was lowered further to 423K or lower, however, maximum resistivity reappeared. At the temperature lower than or equal to 423K but higher than the GP zone solvus, the alloys were not homogeneous but had clusters of solute atoms or fluctuation of solute concentration. Inhomogeneous distribution of solute atoms may affect the aging behavior after quenching from that temperature.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 Alloys1317ENAkiraSakakibaraTadashiTanimotoTakahisaMatsushimaNorioHosokawaTerutoKanadaniRepeated 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 Okayama0475-00712611991Effect of Surface and Grain Boundary on the Reversion of Age-Hardened Al-15mass % Zn Alloy17ENAkiraSakakibaraTerutoKanadaniReversion 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 Okayama0475-00713021996Effect of the Soft Surface Layer on Fatigue Strength of LowTemperature Aged Al-2mass % Cu Alloy913ENAkiraSakakibaraTerutoKanadaniFatigue 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 Okayama0475-00712411989Effects of Drive System Lubricant Additives upon Rolling Fatigue of Carburized and Hardened Steel Rollers112ENAkiraYoshidaYujiOhueMasahiroFujiiTo clarify the effects of a drive system lubricant additive upon rolling fatigue of rollers manufactured from carburized and hardened steel, three types of oil were used as lubricants: one mineral base oil and the other two mineral base oils to which an S-P additive package and ATF additive package were added, respectively. These specimens were tested for sliding/rolling fatigue and examined for failure on the surface, rolling fatigue strength, and other properties. Roller surface temperatures and inter-roller frictional coefficients were found scarcely affected by the type of oil used. Irrespective of the difference in oil type, failure on the surface was found to be entirely spalling attributable to cracks generated in the subsurface. The depth at which spalling cracks had taken place was found nearly coincident with the depth at which a ratio of reversing orthogonal shear stress to hardness had amplitude A(Tyz/Hv) maximized. These depths were larger as Hertz stress became more prominent. Nevertheless, they were found hardly affected by the type of oil. Although rolling fatigue strength did not show a significant difference dependent upon the type of oil, it may be said that fatigue life would be somewhat negatively affected by an extreme pressure coated film with a content of sulfur and phosphorus.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115442010Effects of the Cultivation Method on the Characteristics or Gene Expression Profiles of Aspergillus oryzae Using mCD or DPY Media7383ENHiroyukiImanakaSoukichiTanakaBinFengKoreyoshiImamuraKazuhiroNakanishiWe used modified Czapek-Dox (mCD) or dextrin-peptone-yeast extract (DPY) media to cultivate a filamentous fungus, Aspergillus oryzae IAM 2706 by three different cultivation methods, i.e., shaking-flask culture (SFC), agar-plate culture (APC), and membrane-surface liquid culture (MSLC), to identify the differences in cultivation behaviors and gene transcriptional profiles. The fungi cultivated by APC or MSLC secreted a greater number of different proteins/enzymes in larger quantities compared with fungi cultivated by SFC, particularly when DPY medium was used. In particular, the amounts of protease secreted by fungi cultivated via MSLC or APC were much greater compared with SFC. When mCD medium was used, α-amylase activity was barely detectable in all cultures while the activity was detected in MSLC and APC in a quantity that was several times higher than that in SFC using DPY medium. SDS-PAGE analysis and N-terminal amino acid sequences confirmed 6 proteins in the culture supernatants when DPY medium was used. Among these proteins oryzin (an alkaline protease) and α-amylase were detected at much higher levels in APC and MSLC compared with SFC, which was consistent with
the measured activity of the secreted enzymes. However, when mCD medium was used, only oryzin was detected in significant amounts in MSLC and APC. Microarray analyses of the fungi cultivated by SFC, APC or MSLC using either mCD or DPY media indicated that the gene transcriptional profile of the MSLC sample was similar to that of the APC sample but different from that of the SFC sample. When mCD medium was used, most of the genes that were up-regulated 10-folds or greater in the MSLC sample relative to the SFC sample were unknown or predicted proteins. Transcription of the oryzin gene was only slightly up-regulated in the MSLC sample while transcription of the α-amylase gene was slightly down-regulated. On the other hand, when DPY medium was used, many known genes including the oryzin gene were up-regulated in the MSLC sample versus the SFC sample.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 Approach4651ENKeisukeKadonoChiekoTotsujiKenjiTsurutaHirooTotsujiWe 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 Okayama0475-00712711992Electronic States and Electron Wave Transfer in Coupled Quantum Wires and Its Control by Externally Applied Electric Field6579ENShigetoshiNaraHirooTotsujiQuantum 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 Okayama0475-00712911994Electronic States in Semiconductor Quantum Dot with Fluctuating Interfaces714ENHirooTotsujiShigetoshiNaraChiekoTotsujiEffects 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 Okayama0475-00713011995Electronic Structure of Mixed Perovskite Oxides8997ENChiekoTotsujiHirooTotsujiBased 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 Okayama0475-0071341-22000Energy Distribution in Electrical Discharge Machining with Graphite Electrode1926ENAkiraOkadaYoshiyukiUnoIsaoOkajimaIn 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 Okayama0475-00712921995Estimation of Body Structure by Biomechanical Impedance2937ENHisaoOkaTakashiFukudaIn the stiffness evaluation from the skin surface, the body structure under the skin, like a bone and muscle, influences on the measurement results. The authors developed the measurement system of biomechanical impedance with applying a vibration of acoustic frequency onto the body surface. We measured the viscoelasticity of the silicone-gel model, which involves metal blocks, from
the gel surface by using this system. The internal structure of model is estimated from the relation between the viscoelasticity and the distance from the gel surface to the internal block. Applying this method, the shape of ribs of the right chest are estimated. The shapes and viscoelasticity of silicone-gel tumor model, which has two different tumors, are also estimated.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713722003Estimation of Ground Resisitivity Distribution Using 3D DRM Charge Simulation Modelling4560ENWeiXuY.ZhaoT.HorikaneT.HayataH.TosujiY.KagawaResistivity distribution sounding of the non-homogeneous earth is important for electrical ground system design, geophysical prospecting and survey or monitoring the groundwater flow level. The previous paper presented that the direct inversion of the electric resistivity distribution in a domain is possible from the impedance data measured over the domain boundary using the dual reciprocity boundary element modelling in two-dimentional field [1]. The proposed inversion technique is extended to the distribution in three-dimensional space [2]. This technique is capable of inversion without iteration and meshing of the domain. Electric field with spatially varying conductivity is governed by Laplace equation, which is transformed into a Poisson-type expression with an inhomogeneous term involving the conductivity difference as a source term. Dual reciprocity method (DRM) is a technique for transforming the domain integral associated with the inhomogeneous term in Poisson equation into the boundary integral expression. The resistivity distribution in the field can thus be identified from the data observed over its boundary, for which some examples are demonstrated [2]. In this paper, the examination is extended to the case where only the data measured over the single surface is used for the inversion.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Estimation of Internal Viscoelasticity by Mechanical Impedance2127ENHisaoOkaTakahikoNakamuraIn evaluating the stiffness of skin surface, internal structures such as bone and muscle often affect the measurements. In the present paper, acoustic random vibration is used to estimated the viscoelasticity of a silicone-gel model. This viscoelasticity, which includes two different stiffness strata, is first estimated using a mechanical impedance spectrum, which describes the relation between the depth and viscoelasticity of internal objects. This method is applied to the depth of a silicone-gel tumor model measured by ultrasound imaging and the viscoelasticity of internal gel can be accurately estimated.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Estimation of Loosening of Knee Joint Prosthesis2937ENHisaoOkaMasakazuOhshimaKnee replacement arthroplasty is indicated for the patient with advanced knee pain, knee deformation, and knee functional disorder. The aim of this study was to estimate loosening after a knee replacement arthroplasty. Loosening is measured by a frequency response function, and mobility by random vibration. The modal parameters for the knee joint are obtained by applying a modal analysis to the frequency response function. The values decrease as the knee joint prosthesis loosened. These parameters serve as an index for the condition between a thighbone and the prosthesis. The various indexes will greatly clarify the stage of advance in the loosening of knee-joint prostheses.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713021996Estimation of Muscle Fatigue of Low Back upon the Muscle Stiffness1520ENHisaoOkaShiroFujiwaraAn estimation of muscle fatigue is very important study and many laboratory researchers had done actively in this field. The excellent measurement and analysis methods, however, have not established yet. The aim of this study was to investigate the muscle fatigue of low back, caused by sitting on the vehicle seat for a long time. The muscle viscoelasticity and the EMG (Electromyogram) were measured. The authors proposed the objective muscle fatigue index that was obtained from the result of PCA (Principal Component Analysis) by using the measured varlables. The objective muscle fatigue index suggests an adequate correlation with the subjective fatigue on the vehicle seat.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713712002Estimation of the screening length and the electric charge on particles in single-layered dusty plasma crystals1114ENChiekoTotsujiMuhammad S.LimantKenjiTsurutaHirooTotsujiA theoretical approach which has been successful in reproducing results of molecular-dynamics
simulations on dusty plasmas is applied to estimate the screening length and the electric charge of two-dimensional dust crystals of melamine particles in the discharge chamber experiment. It has been found that the screening length is of the same order of magnitude as the inter-particle distance and the electric charge decreases on increasing number density of dust particles.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713612001Evaluation and Selection of Models for Motion Segmentation7990ENKenichiKanataniWe first present an improvement of Kanatani's subspace separation [8] for motion segmentation by newly introducing the affine space constraint. We point out that this improvement does not always fare well due to the effective noise it introduces. In order to judge which solution to adopt if different segmentations are obtained, we present two criteria: one is the standard F test; the other is model selection using the geometric AIC of Kanatani [7] and the geometric MDL of Matsunaga and Kanatani [13]. We test these criteria doing real image experiments.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713612001Evaluation and Selection of Models for Motion Segmentation91106ENKenichiKanataniNaoyaOhtaWe present a theoretically optimal linear algorithm for 3-D reconstruction from point correspondences over two views. We also present a similarly constructed optimal linear algorithm for 3-D reconstruction from optical flow. We then compare the performance of the two algorithms by simulation and real-image experiments using the same data. This is the first impartial comparison ever done in the sense that the two algorithms are both optimal, extracting the information contained in the data to a maximum possible degree. We observe that the finite motion solution is always superior to the optical flow solution and conclude
that the finite motion algorithm should be used for 3-D reconstruction.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 BPM4955ENAnisAhmedShinjiTaniguchiOsamiWadaMingWangRyujiKogaFor 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 Okayama0475-00712811993Evaluation of closed-form analytical models for predicting unsaturated soil hydraulic properties6169ENYujiTakeshitaIichiroKohnoKnowledge of the unsaturated soil hydraulic properties is essential requirement for prediction of seepage flow and contaminant transport through the vadose zone. Unfortunately, these parameters are usually time consuming and expensive to measure in the field and laboratory. At the present condition, there are few data accumulation for Japanese soils. In this paper, van Genuchten's closed-form
expressions are described to estimate unsaturated soil hydraulic properties. To evaluate the adequacy of these expressions, comparisons are performed between observed and calculated unsaturated hydraulic properties for typical Japanese soils.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 Mirror99110ENMingWangOsamiWadaRyujiKogaA 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 μm, 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 μm. 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 Okayama1349-6115432009Experimental Conditions for Observation of Thermodynamic
Instability and Critical Point of Fine Particle (Dusty) Plasmas2731ENHirooTotsujiWhen 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 Okayama0475-00714112007Experimental Evaluation of Geometric Fitting Algorithms6372ENKenichiKanataniYasuyukiSugayaThe 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 Taubin’s 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 Okayama0475-00713622002Experimental Verification of Common-Mode Excitation Model for PCB Having Partially Narrow Return Path8389ENTetsushiWatanabeOsamiWadaRyujiKogaYoshitakaToyotaTakuyaMiyashitaSuppression of common-mode current is important to achieve electromagnetic compatibility of high-speed and high-density electronic circuits. The authors have focused on the common mode current flowing on a printed circuit board (PCB) to explain the excitation mechanism. A narrow ground pattern in microstrip structure excites common-mode current. In the previous paper, the authors explained the mechanism of common mode generation by means of "current division factor" for simple PCBs. The estimated radiation from a simple PCB agreed well with measured one. In this paper, the authors extend the theory to be applied to generalize ground structure. The validity of the theory is confirmed by comparing the measured radiation and the estimated value using the common-mode model for a test PCB. The estimated radiation agrees well with the measured one within 3 dB up to 900 MHz.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712611991Experimental and Theoretical Study on a Transient, Turbulent Free Hydrogen Gas Jet Issuing into Still Air2741ENEijiTomitaYoshisukeHamamotoDistributions of hydrogen gas concentration in a suddenly started, single shot hydrogen gas jet issuing from a 1 mm diameter injector into still air were measured using laser interferometry method. This unsteady, turbulent free jet flow has also been calculated using the two-equation, high Reynolds number version of k-ε turbulence model and hybrid scheme for treating combined diffusion and convection in the SIMPLE algorithm. The injection pressure was 0.5 MPa for which predicted and measured temporal jet tip penetration distributions indicate that the jet discharged into still air at Mach 0.25. The level of agreement between present prediction and measurement is good in some regions and poor in others.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115432009Extension Field for Xate Pairing with Freeman Curve108112ENKentaNekadoHidehiroKatoYasuyukiNogamiYoshitakaMorikawaRecently, pairing-based cryptographies such as ID-based cryptography and group signature have been studied. For fast pairing calculation, not only pairing algorithms but also arithmetic operations in extension field must be efficiently carried out. The authors show efficient arithmetic operations of extension field for Xate pairing especially with Freeman curve.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 Video
Sequence5662ENYasuyukiSugayaKenichiKanataniWe 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 Okayama1349-6115442010FDTD Analysis on Optical Connement Structure
with Electromagnetic Metamaterial16ENKenjiTsurutaIn this paper, we investigate a light-confinement phenomenon in the structure which has triangular latice composed of Double NeGative Metamaterial (DNGM). In
geometrical optics consideration, this structure is expected to confine lights completely by sequential refractions in the structure. We demonstrate it by using the two dimensional finite-difference time-domain simulations. We introduce Drude-Lorentz model for dielectric and magnetic dispersion of the material at optical frequencies. We analyze quantitatively the effects of energy loss in the DNGM on the light-confinement
efficiency.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-Dimensional
Phononic Crystals using Parallel Computer1621ENKenjiTsurutaChiekoTotsujiHirooTotsujiThe 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 acoustic“lens effect”with 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 Okayama0475-00712611991Facilitated Diffusion of Carbon-Dioxide in a Living Body Liquid Film2126ENShigeruNozuHideoInabaA 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 Okayama0475-00713311998Facility Layout Linked with Scheduling Problem by Genetic Algorithm and Tabu Search5964ENHirokazuOsakiIn this paper, we propose a method to solve simultaneously facility layout problem and scheduling problem. About a initial random layout planning, the production scheduling and the transportation scheduling of AGV are obtained by using priority rules. From the obtained transportation scheduling, the critical transportation and the closeness rating are obtained. Facility layout is renewed by the combined procedure of genetic algorithm and tabu search in order to reduce the material handling cost. By using this renewed facility layout, the production scheduling and the transportation scheduling of AGV are also revised until no further improvement is possible.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071381-22004Factorization without Factorization: Complete Recipe6171ENKenichiKanataniYasuyukiSugayaThe Tomasi-Kanade factorization for reconstructing the 3-D shape of the feature points tracked through a video stream is widely regarded as based on factorization of a matrix by SVD (singular value decomposition). This paper points out that the core principle is the affine camera approximation to the imaging geometry and that SVD is merely one means of numerical computation. We first describe the geometric structure of the problem and then give a complete programming scheme for 3-D reconstruction.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 Roof112ENHideoInabaAkihikoHoribeThe 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 Okayama0475-00714212008Fast Exponentiation in Extension Field with Frobenius Mappings3643ENHidehiroKatoKentaNekadoYasuyukiNogamiYoshitakaMorikawaThis 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 Okayama0475-00714012006Fatigue Crack Propagation Behavior Bent from Precrack under Mixed-Mode Conditions - Noting the Crack-Surface Contact due to a Compressive Residual Stress along a Precrack -18ENYouLiMaKenichiShimizuTashiyukiToriiA testing for bent fatigue crack propagation under mixed-mode conditions was carried out using fatigue and annealed slant precracks with different slant angles, β ,defined as the angle between loading and precrack directions in a rectangular plate. As a result, bent fatigue crack from the fatigue precrack with β =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 β =60deg. and from the annealed precracks with both slant angles of β =60deg. and β =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 β . 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 Okayama0475-00714212008Fatigue Crack Propagation Evaluated by Electric Resistance and Ultrasonics in Copper Film Bonded to Base Metal with Resin104109ENMADonghuiTashiyukiToriiKenichiShimizuAkiraMatsubaAs model specimens of surface film-bonded materials, pure copper films with a thickness of 100μm 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 Okayama0475-00712521991Fatigue Strength of Age-Hardened Al-Zn Alloys under Repeated Tensile Loading1723ENAkiraSakakibaraTerutoKanadaniToshiakiKaneedaNorioHosokawaEffect 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 100μm 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 Okayama0475-0071381-22004Feature Extraction and Classification of Operational Data for Diagnosis of Hot Strip Mill Looper Control1527ENTakashiTorigoeMasamiKonishiJunImaiTatsushiNishiIn these days, mechanical systems are becoming more complex and highly automated. So, there exist wide variety of demands for reliable diagnostic technology. A reliable data analysis and quantitative diagnosis method of mechanical system is necessary for the purpose. In this paper a quantitative diagnosis method for looper height control system has been developed based on neural network technologies. The wavelet transformation is used for pre-processing to analyze characteristics of looper height control system. And, self organizing map neural network is used for the purpose of classification based on the pre-processed data. After that, the classified results are used for quantitative diagnosis in hierarchical neural network.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712421990Film Continuity Problem on Journal Bearing Design1730ENTadatakaKonishiMitsuruBabaPressure 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 Okayama0475-00712421990Fine Particles of Ti and Ti-Mo Alloy Prepared by Gas Evaporation19ENMasayukiUmemotoYoshitoTakemotoAkiraSakakibaraMoritakaHidaFine particles of Ti-Mo alloy were prepared by evaporation. When Ti-40at % Mo alloy was evaporated on tungsten filament, fine particles of Ti contaminated with W were obtained. These particles were polyhedron in shape and 10～250nm in diameter. Average diameter and size distribution increased with pressure of argon gas (100～600 Torr). When pure Ti was placed on the Mo filament and evaporated from melt down of heated Mo filament in helium gas, fine particles of pure Ti and of Ti-Mo alloy were obtained. In this case, Ti particles were of indeterminate form and of several tens nm in diameter, and their diffraction pattern was of common α-Ti. On the other hand, composition of the Ti-Mo particles was determined to be 18at % Mo by an analysis of EDX. Structure of Ti-Mo particles could not be determined because their diameters were more than 600nm. The temperature of Mo filament, for the most part, was about 1800℃, and there pure Ti particles were produced. The temperature of the fused part of the filament was locally higher than 2600℃, and there Ti-Mo particles were produced. Fine structures of contact region among some Ti particles were observed with HRTEM.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 Waveguides6373ENYukioKagawaOptical 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 Okayama0475-00713011995Finite Elements with Divergence-free Shape Function and the
Application to Inhomogeneously-loaded Waveguide Analysis3546ENYukioKagawaDivergence-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 Okayama0475-00712321989Flow of Rarefied Vapour past a Liquid Sphere3344ENKyojiYamamotoThis 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 Okayama0475-0071351-22001Focusing Characteristic Analysis of Circular Fresnel Zone Plate Lens5361ENYukioKagawaFresnel 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 Okayama0475-00713712002For Geometric Inference from Images, What Kind of Statistical Model Is Necessary?1523ENKenichiKanataniIn order to facilitate smooth communications with researchers in other fields including statistics, this paper investigates the meaning of "statistical methods" for geometric inference based on image feature points, We point out that statistical analysis does not make sense unless the underlying "statistical ensemble" is clearly defined. We trace back the origin of feature uncertainty to image processing operations for computer vision in general and discuss the implications of asymptotic analysis for performance evaluation in reference to "geometric fitting", "geometric model selection", the "geometric AIC", and the "geometric MDL". Referring to such statistical concepts as "nuisance parameters", the "Neyman-Scott problem", and "semiparametric models", we point out that simulation experiments for performance evaluation will lose meaning without carefully considering the assumptions involved and intended applications.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 Cylinder1724ENHideoInabaShigeruNozuHeat 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 Okayama0475-00712421990Functional Testing of an ALU8998ENTokumiYokohiraThis paper considers a test set for an ALU with look ahead carry generators(LCGs). The ALU is logically partitioned into two groups of blocks, the group of one-bit operation units and LCG group. Each group is tested in parallel and exhaustively, independent of the other. And an easily testable design is applied to several blocks for decreasing the number of the input combinations of them. Under the easily testable design, a minimum test set for each group is generated, and the upper and lower bounds for
a minimum test for the ALU are derived. The difference of the lower and upper bounds is not large, and a test set whose number of test vectors is equal to the upper bound can be easily obtained as the union of minimum test sets for two groups. Hence, the union can be used as a complete and practical test set for the ALU.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714212008Fundamental Matrix Computation: Theory and Practice1835ENKenichiKanataniWe 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 Okayama0475-00712411989Fundamental Study on Electrical Discharge Machining1324ENYoshiyukiUnoToshikatsuNakajimaOsamuEndoThe 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 Okayama0475-00713722003Gain Tuning Model of Human Expert for Looper Height Control in Hot Strip Rolling2944ENShuyaImajoMasamiKonishiJunImaiTatsushiNishiIn hot strip rolling mills, the looper control system is automated. However, the looper's behavior tends to be unstable in threading. Therefore, human expert always intervenes and stabilizes the looper's behavior by tuning PID gains and interposing manipulation variable of looper control system. In this paper, we propose a method based on the recurrent neural network to express PID gains tuning action by human. Furthermore, we propose two methods to update the model by learning. To check the effectiveness of the proposed learning methods, numerical simulation applied to the looper height control is carried out.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00714012006Generating Dense Point Matches Using Epipolar Geometry4452ENYasuyukiSugayaKenichiKanataniYasushiKanazawaDense 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 “naturalness of the 3-D shape” 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 Okayama0475-0071381-22004Generation of IgM and IgG1 monoclonal antibodies with identical variable regions: comparison of avidity9196ENNaokiKanayamaKimiYamakoshiMasaakiKiyomiMasakiMagariHitoshiOhmoriGenerally, IgM antibodies (Abs) produced in a primary immune response show lower affinity for an inducing antigen (Ag) compared with the corresponding IgG Abs that are major switched isotypes formed in the secondary response. An IgM molecule is a pentamer with 10 Ag-binding sites that will contribute to an increase of avidity for an Ag. To estimate the contribution of the pentameric structure to the avidity of an IgM Ab, we generated IgM and IgG1 monoclonal Abs (mAbs) with identical V regions that are specific for 4-hydroxy-3-nitrophenylacetyl (NP) by in vitro class switching of B cells followed by the cell fusion with a mouse myeloma cell line. Compared with an anti-NP IgG1 mAb, the corresponding IgM mAb showed much higher avidity for NP-conjugated
bovine serum albumin, which was drastically reduced after being dissociated into monomers.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 Applications111120ENMasahiroTanakaTetsuzoTaninoMutation 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 Okayama0475-00714212008Geometric BIC1017ENKenichiKanataniThe author introduced the "geometric AIC" and the "geometric MDL" as model selection criteria for geometric fitting problems. These correspond to Akaike’s "AIC" and Rissanen's "BIC", respectively, well known in the statistical estimation framework. Another criterion well
known is Schwarz’ "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 Okayama0475-00712811993Ground State of Coupled Quantum Wires2738ENHirooTotsujiShigetoshiNaraThe 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 Okayama0475-00712711992Heat Transfer Characteristics of Two Phase Closed
Thermosiphon for Geothermal Energy (1st Report: Measurement on Heat Transfer Coefficient)1126ENHideoInabaTo 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 Okayama0475-00712711992Heat Transfer Characteristics of Two Phase Closed Thermosiphon for Geothermal Energy (2nd Report: Heat Transfer Behavior on Site)2732ENHideoInabaHeating 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 Okayama0475-00714112007Heat and Mass Transfer Analysis of Fluidized Bed Grain Drying5262ENHideoInabaAkihikoHoribeNaotoHarukiThe 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 Okayama1349-6115442010High Accuracy Homography Computation without Iterations5059ENKenichiKanataniWe present highly accurate least-squares (LS) alternatives to the theoretically optimal maximum likelihood (ML) estimator for homographies between two images. Unlike ML, our estimators are non-iterative and yield solutions even in the presence of large noise. By rigorous error analysis, we derive a “hyperaccurate” estimator which is unbiased up to second order noise terms. Then, we introduce a computational simplification, which we call “Taubin approximation”, without incurring a loss in accuracy. We experimentally demonstrate that our estimators have accuracy surpassing the traditional LS estimator and comparable to the ML estimator.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 Crane6174ENMaoKawamuraMasamiKonishiKatukiYamagataKoichiShimomuraIn 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 System7592ENKeitaOheMasamiKonishiJunImaiAs 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 Okayama1349-6115452011Hyper Least Squares and Its Applications1526ENKenichiKanataniPrasannaRangrajanYasuyukiSugayaHirotakaNiitsumaWe present a new least squares (LS) estimator, called “HyperLS”, specifically designed for parameter estimation in computer vision applications. It minimizes the algebraic distance under a special scale normalization, which is derived by rigorous error analysis in such a way that statistical bias is removed up to second order noise terms. Numerical experiments suggest that our HyperLS is far superior to the standard LS and comparable in accuracy to maximum likelihood (ML), which is known to produce highly accurate results in image applications but may fail to converge if poorly initialized. Our HyperLS is a perfect candidate for ML initialization. In addition, we discuss how
image-based inference problems have different characteristics form conventional statistical applications, with a view to serving as a bridge between mathematicians and computer engineers.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama1349-6115442010Hyperaccurate Ellipse Fitting without Iterations4249ENKenichiKanataniThis paper presents a new method for fitting an ellipse to a point sequence extracted from images. It is widely known that the best fit is obtained by maximum likelihood. However, it requires iterations, which may not converge in the presence of large noise. Our approach is algebraic distance minimization; no iterations are required. Exploiting the fact that the solution depends on the way the scale is normalized, we analyze the accuracy to high order error terms with the scale normalization weight unspecified and determine it so that the bias is zero up to the second order. We demonstrate by experiments that our method is superior to the Taubin method, also algebraic
and known to be highly accurate.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 Models2533ENYukioKagawaIdentification 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 Okayama0475-00713912005Immobilization of Photoelectric Dye on the Polyethylene Film
Surface1620ENTetsuyaUchidaSanaeIshimaruKaoruShimamuraAkihitoUjiToshihikoMatsuoHiroshiOhtsukiPE film was treated with fuming nitric acid at 80℃ for 20 min, resulting in introduction of COOH moieties on the film surface. The COOH’s 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 Okayama1349-6115442010Improved Multistage Learning for Multibody Motion Segmentation2431ENKenichiKanataniWe present an improved version of the MSL method of Sugaya and Kanatani for multibody motion segmentation. We replace their initial segmentation based on heuristic clustering by an analytical computation based on GPCA, fitting two 2-D affine spaces in 3-D by the Taubin method. This initial segmentation alone can segment most of the motions in natural scenes fairly correctly, and the result is successively optimized by the EM algorithm in 3-D, 5-D, and 7-D. Using simulated and real videos, we demonstrate that our method outperforms the previous MSL and other existing methods. We also illustrate its mechanism by our visualization technique.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 Modification117121ENYukiShirosakiKanjiTsuruSatoshiHayakawaAkiyoshiOsakaSeisukeTakashimaγ-Methacryloxypropyltrimethoxysilane (γ-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 γ-MPS.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713912005Improving Methods of Wear Resistance in Heavy Loaded Sliding
Friction Pairs16ENMasahiroFujiiAkiraYoshidaImprovement of wear resistance and durability of machine elements with sliding friction pairs is the important tribological problems. The wear resistance
has been determined with many configurative parameters, technological parameters, and operational parameters. In this study kinematics of cylindrical joint (CJ), whose motion is reciprocating and rotating, and influence of various parameters on wear resistance of friction pair was investigated.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 Asymmetry2226ENHirooTotsujiChiekoTotsujiKenjiTsurutaFor 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 Okayama0475-00713321999Inspection Method by Comparing CAD Figure with Processed Image97103ENMitsuruJindaiHirokazuOsakiYasuhiroKajiharaYoshiomiMunesawaWe 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 Okayama0475-00713321999Intelligent Monitoring System Using Multiviewpoints for Teleperation9196ENYoshiomiMunesawaHirokazuOsakiYasuhiroKajiharaIn 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 Okayama0475-00712821994Internal Structure and Phase Transformation of Ti-Mo Alloy Fine Particles17ENYoshitoTakemotoAkiraSakakibaraMoritakaHidaFine particles of Ti-Mo alloy have been prepared by means of arc method, and investigated on internal structure and phase transformation using HR-TEM and EDS. Martensite phase was observed in a particle containing comparatively low concentration of Mo, and ω phase was also found to exist in a nearly 14 % M0 particle. The structure of the ω phase in the fine particle is expanded and remarkably unstable in comparison with the bulk sample, so that it has disappeared in a few seconds during TEM observation. Moreover, the β structure of Ti-Mo particles has changed to the unusual fcc phase with irradiation of a strong electron beam.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00713121997Internal Structure and Phase Transformation of Ti-V Alloy Fine Particles1120ENYoshitoTakemotoMoritakaHidaFine particles of Ti-V alloy were prepared by means of arc method and were investigated on internal structure and phase transformation using HR-TEM and EDS. Martensite phase was observed in a particle containing comparatively low concentration of V, and ω phase was also found to exist in a nearly 15% V particle. The structure of the ω phase in the fine particle is remarkably expanded in comparison with the bulk sample, and the ω phase is unstable, so that it has disappeared in a few seconds during TEM observation.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071321-21998Internal Structure and Viscoelasticity Estimation by a Mechanical Impedance - In case of a vibrating disk -1522ENMasahiroMoriHisaoOkaIn a stiffness estimation of living body, an internal structure under the skin influences the measured results. Because a different stiffness of body caused by bones and muscles is obtained. In this paper, by using a measurement system of mechanical impedance, the relations between a viscoelasticity and a distance from the surface of silicone-gel model is calculated. This relation is applied to silicone-gel tumor model and a shape and a viscoelasticity of semi-sphere silicone-gel tumous are estimated. The obtained results are expressed as a reconstructed 3-D image of shape / viscoelasticity. The revised curve-fitting of mechanical impedance and the cancellation of peripheral vibration influence are proposed in order to increase an estimation acccuracy.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 Effects5564ENHirooTotsujiShigetoshiNaraThe 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 Okayama0475-00713912005Large-Scale Molecular Dynamics Simulation of Coulomb
Clusters: A Finite-Temperature Analysis5255ENKatsuyaKanamoriChiekoTotsujiKenjiTsurutaHirooTotsujiThermal 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 Okayama0475-0071351-22001Laser Welding of Slices of Magnetic Circuit2128ENVolodymyrS.kovalenkoYoshiyukiUnoYasuhiroOkamotoM.AnyakinA.LutayKhaled Al.ShubulIn 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 Okayama1349-6115472013Lazy Random Walk Efficient for Pollard’s Rho Methoｄ Attacking on G3 over Barreto-Naehrig Curve (Corrected)2532ENKentaNekadoYusukeTakaiYasuyukiNogamiPairing–based cryptosystems are well implemented with Ate–type pairing over Barreto–Naehrig (BN)
curve. Then, for instance, their securities depend on the difficulty of Discrete Logarithm Problem (DLP)
on the so–denoted G3 over BN curve. This paper, in order to faster solve the DLP, first proposes to
utilize Gauss period Normal Basis (GNB) for Pollard’s rho method, and then considers to accelerate the
solving by an adoption of lazy random walk, namely tag tracing technique proposed by Cheon et al.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 Alloy14ENAkiraSakakibaraKeiyuNakagawaTerutoKanadaniEffect 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 Okayama0475-00712421990Mean Time Between Failure of Ring Arbiter with Requests Differing in Incidences7987ENYoichiroSatoIn 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 Okayama0475-00713321999Measurement System of Biomechanical Properties for Portable Use4550ENHisaoOkaIt is difficult to evaluate a biomechanical properties quantitatively. The authors developed the measurement system of biomechanical properties formerly but it is on a large scale because of the use of personal computer. In this study, the portable measurement system of biomechanical impedance/mobility is developed. To establish a rapid measurement, a random vibration is adopted in input signal. The system consists of the measuring probe, amplifier, and a note-typed personal computer. The measurement probe is developed newly, and has an overall length of 9 ㎝ (without a handle) and a total weight of about 500 g. The measurement program is also developed and is available to any computer which is worked under MS DOS compatible in Windows 95/98 operating system. The biomechanical spectra of thigh, temple and forehead are obtained and they show three typical spectrum patterns.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-0071221988Measurement of Biomechanical Impedance - Its device and measuring conditions114ENHisaoOkaTatsumaYamamotoBiomechanical impedance is relatively small compared to industrial mechanical impedance. Thus it is difficult to measure it precisely. A biomechanical impedance measuring system was developed for portable use by means of random excitation. This system doesn't require a fixed body and vibrator supporting apparatus. In order to obtain an impedance spectrum, the FFT processing is performed using a personal computer. The spectra of the biomechanical impedance which is measured on body surfaces depend on body positions and can be roughly classified into three spectra patterns : soft, stiff and intermediate. During the measurement, the measuring conditions (preload, diameter of the vibrating tip etc.) influence the results. However, it became clear that the linearity of the biomechanical impedance was satisfied in the limited measuring conditions. Accordingly it is possible to standardize the impedance and to compare it with the results under different measuring conditions.No potential conflict of interest relevant to this article was reported.Faculty of Engineering, Okayama UniversityActa Medica Okayama0475-00712411989Measurement of Emotional Response by Similarity in Patterns of Galvanic Skin Reflex6372ENYoshitakeYamamotoHisaoOkaTatsumaYamamotoThere is no doubt that many people feel the peace of mind or the pleasures of senses in appreciating music. But the estimation of the effect is very difficult and the objective estimation can be hardly done. This study proposed the objective estimating method of human emotion utilizing galvanic skin reflex (GSR) which reflects a human psychological activity. In this method, not by individual response, but by the series of response and pattern of appearance of GSR, the emotional response under appreciating music was investigated. In the case of appreciation of the same classic music to several subjects, the individual GSR responses are random and remarkable characteristic could not be find on the results. However, on the patterns of appearance of GSR, the patterns obtaining from the same generation are much similar each other and the patterns obtaining from different generation are less similar. It was cleared that the same music gave different effect on different generations.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 Spectrometry4553ENNaokiKagawaOsamiWadaXuHaiRyujiKogaHiroyaSanoKazuyukiInubushiA 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 Okayama0475-00712411989Measurement of Microvibration on the Skin Surface7380ENHisaoOkaYoshitakeYamamotoTatsumaYamamotoThere is a small vibration which goes undetected by the naked eyes. It is called a microvibration (MV) or a minor tremor (MT). The MV on the body surface is expected to apply to a clinical examination of the autonomic nervous system. It is not cleared why and how the MV occurs, but there are many papers about its occurrence and clinical
application. In this study, MV measuring system, its estimation and basic characteristics are examined. The difference between head MV and thenar MV, individual MV and diurnal and seasonal change are discussed. The power spectrum of MV is obtained using an autoregressive model.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 oil1930ENSeiichiWashioSatoshiTakahashiChikashiImotoAtsumasaYoshidaThe 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 Okayama0475-00712521991Mechanical Characteristics of Cast Ti Fiber-Reinforced Mg Composite18ENHiroyukiOkadaMoritakaHidaAkiraSakakibaraYoshitoTakemotoTensile 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 Okayama0475-00714012006Melting of Spherical Yukawa Clusters Analyzed by Monte Carlo
Simulation3135ENTakafumiOgawaChiekoTotsujiKenjiTsurutaHirooTotsujiWe 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 Okayama0475-00712621992Memory Search using Genetic Algorithms and a Neural Network Model111128ENShigetoshiNaraAn 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 Okayama0475-00712521991Mesh Generation for Convex 3-Dimensional Domain123133ENTakeoTaniguchiChikashiOhtaThe 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 Okayama0475-00714112007Method for Production Planning and Inventory Control in OilRenery2030ENTakujiImamuraMasamiKonishiJunImaiIn 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 Okayama0475-0071351-22001Methods for Tele-Operation of Mobile Type Maintenance Robot155161ENYoshiomiMunesawaYasuhiroKajiharaHirokazuOsakiThis 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.