JaLCDOI 10.18926/19599
FullText URL Mem_Fac_Eng_OU_31_2_53.pdf
Author Fujihara Yutaka| Osaki, Hirokazu|
Abstract This paper presents a method using simulated annealing(SA) and genetic algorithm(GA) to solve the plant layout problem in which the layout is evaluated by material handling cost and maintainability. In the former study about facility layout problem, it was either the minimization of the objeective function consisting of transport cost or the maximization of the objective function consisting of closeness rating. In this paper, both transport cost and maintainability were included in the objective function to be minimized. The plant layout problem, this paper proposes the heuristic procedures to obtain a suboptimal layout solution by combining SA with GA. From the simulation by computer, it concluded that the method which SA is combined with GA is more efficient than the method which utilizes SA and GA independently.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 53
End Page 60
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309131
JaLCDOI 10.18926/19591
FullText URL Mem_Fac_Eng_OU_31_2_21.pdf
Author Oka, Hisao| Nakamura, Takahiko|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 21
End Page 27
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309105
JaLCDOI 10.18926/19596
FullText URL Mem_Fac_Eng_OU_31_2_45.pdf
Author Osaka, Akiyoshi| Kobayashi Keizo| Hayakawa, Satoshi| Ohtsuki, Chikara|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 45
End Page 51
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309181
JaLCDOI 10.18926/19589
FullText URL Mem_Fac_Eng_OU_31_2_11.pdf
Author Ishii Kouta| Takemoto, Yoshito| Hida, Moritaka|
Abstract Fine 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 11
End Page 20
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309004
JaLCDOI 10.18926/19603
FullText URL Mem_Fac_Eng_OU_31_2_67.pdf
Author Li Zhenzi| Osaki, Hirokazu| Kajihara, Yasuhiro|
Abstract In this paper, we propose the price determination method using the parameter of the price elasticity that shows the relation between price and demand. Firstly, the state of the price elasticity is examined under the condition that the relation between price and demand are assumed by the inverse proportional function, the linear function and the quadratic function. Secondly, the profit is estimated for each product by break even point analysis. And the price is determined under the condition that the relation between the demand and price is shown by one of three demand-pridce functions above mentioned.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 67
End Page 72
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309056
JaLCDOI 10.18926/19601
FullText URL Mem_Fac_Eng_OU_31_2_61.pdf
Author Yamada Mitsuru| Osaki, Hirokazu|
Abstract At 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 61
End Page 65
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309050
JaLCDOI 10.18926/19619
FullText URL Mem_Fac_Eng_OU_31_1_1.pdf
Author Sakakibara, Akira| Nakagawa, Keiyu| Hosokawa, Norio| Kanadani, Teruto|
Abstract Dependence of precipitation hardening on the distance from specimen surface and effect of the surface layer on the fatigue strength of an Al-1.2mass% Si alloy were studied by microhardness test, transmission electron microscopy and repeated tension fatigue test. Rate of age-hardening was slower in the vicinity of surface than in the interior of the specimen aged at 423K after quenching from 853K. The result of the electron microscopy was that the size ot Si precipitates formed in the vicinity of surface was smaller than in the interior of specimen aged for 6ks at 423K. This difference was considered to be caused by the effect of the surface as vacancy sinks which slowed down the growh of Si precipitates in the vicinity of the specimen surface. A specimen surface layer whose hardness was different from that of the specimen interior was formed at the vicinity of the surface when the specimen was aged at relatively low temperature such as 423K. The fatigue strength in repeated tensile test ot the specimen did not depend on whether the specimen surface layer was present or not.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-12-27
Volume volume31
Issue issue1
Start Page 1
End Page 3
ISSN 0475-0071
language 英語
File Version publisher
NAID 120005816788
JaLCDOI 10.18926/19622
FullText URL Mem_Fac_Eng_OU_31_1_5.pdf
Author Shimamura, Kaoru| Zhang Chunxiao| Uchida, Tetsuya|
Abstract Rigid polymer poly(p-phenylene benzobisthiazole) was crystallized from dilute solution. Electron microscopy showed that upon quenching, flat fibrils with several nm thick were produced. Subsequent heat treatment in solvent changed the fibril into "shish-kebab". On the other hand, by isothermal crystallization, an aggregate of parallel rod-like crystals was obtained. The molecular chains were accommodated normal to the rod. Based on the observation of crystal morphology, the isothermal crystallization mechanism was proposed. Because of regidity of polymer chains and wide distribution of the molecular length, the chain ends were inevitably included within the crystals resulting in crystal defects such as axial shift, lattice curvature and edge dislocation which were directly observed by lattice imaging.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-12-27
Volume volume31
Issue issue1
Start Page 5
End Page 10
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309167
JaLCDOI 10.18926/15166
FullText URL Mem_Fac_Eng_OU_31_1_19.pdf
Author Totsuji, Hiroo| Kishimoto, Tokunari| Totsuji, Chieko|
Abstract As a model of dusty plasmas in external fields, Yuka.wa system in a one-dimensional external field is analyzed by molecular dynamics simulations and theoretical approaches. It is shown that particles form clear thin layers (sheets) at low temperatures and the number of layers changes discretely with characteristic parameters of the system, accompanying the rearrangements of whole system from nearly equipartitioned layers to also nearly equipartitioned layers. The number, positions and populations of layers are obtained as functions of characteristic parameters. The shell (sheet) model which has been successful for confined one-component plasmas is extended to this system and results of numerical experiments are reproduced to a good accuracy. The effect of cohesive energy in each layer is of essential importance to reproduce discrete changes in the number of sheets.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-12-27
Volume volume31
Issue issue1
Start Page 19
End Page 33
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307616
JaLCDOI 10.18926/19624
FullText URL Mem_Fac_Eng_OU_31_1_11.pdf
Author Zhang Chunxiao| Tanigawa Satoshi| Uchida, Tetsuya| Shimamura, Kaoru|
Abstract Poly[(benzo[1,2-d:5,4-d']bissthiazole-2,6-diyl)-1,4-phenylene](cis-PBZT)with a relatively high molecular weight was prepared by a new synthesis route. Properties of the synthesized polymer, such as thermostability, liquid crystallinity etc. were investigated and compared with those of trans-PBZT. cis-PBZT was crystallized from dilute solution and the electron microscopy showed that the precipitate was a rod-like crystal similar to that of trans form. In spite of rigid nature of the back bone, cis-PBZT showed poor crystallinity.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-12-27
Volume volume31
Issue issue1
Start Page 11
End Page 17
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309203
JaLCDOI 10.18926/15397
FullText URL Mem_Fac_Eng_OU_30_2_1.pdf
Author Takemoto, Yoshito| Hida, Moritaka| Sakakibara, Akira|
Abstract The mechanism of brittle fracture in Ti-14mass % Mo alloy aged for 1x10(6)s at 623K was studied using transmission electron microscopy (TEM) and dynamic hardness test (DHT) on the structure deformed by means of tensile elongation at elevated temperature or cold rolling. Many band products were observed by TEM in either deformed specimens. These band products were identified to neither slips nor twinning bands, moreover, they were different from α , α ' and α " phases. The band product consisted of β phase and granular unknown phase which was transformed by deformation from ω phase. The newly discovered phase, named β" phase, in the band products had a body-centered triclinic structure. The β" was similar to the ω zone with respect to the morphology and the concentration of Mo, but it resembled β in structure. The result of DHT on the band products and the matrix showed that the band products were softer than the matrix. It is suggested that the band products are easily deformed because of the disappearance of obstacles such as ω phase, and consequently behave like paths to lead cracks preferentially.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 1
End Page 7
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307225
JaLCDOI 10.18926/15393
FullText URL Mem_Fac_Eng_OU_30_2_15.pdf
Author Oka, Hisao| Fujiwara, Shiro|
Abstract An 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 15
End Page 20
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307965
JaLCDOI 10.18926/15387
FullText URL Mem_Fac_Eng_OU_30_2_9.pdf
Author Sakakibara, Akira| Kanadani, Teruto|
Abstract Fatigue 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 9
End Page 13
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307694
JaLCDOI 10.18926/15401
FullText URL Mem_Fac_Eng_OU_30_2_21.pdf
Author Tachibana Hiroyuki| Totsuji, Hiroo|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 21
End Page 25
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307620
JaLCDOI 10.18926/15402
FullText URL Mem_Fac_Eng_OU_30_2_27.pdf
Author Totsuji, Hiroo| Kishimoto, Tokunari| Totsuji, Chieko|
Abstract The behavior of the Yukawa system in external one-dimensional force fields is analyzed by the molecular dynamics simulation. The formation of layered structures at low temperatures is observed and the relation between the number of layers and characteristic parameters of the system is obtained. Since the Yukawa system serves as a model of clouds of dust particles in plasmas (dusty plasma) which play an important role in plasma processes of semiconductor engineering, the results may be useful to control the quality of semiconductor wafers in such processes. In simulations, periodic boundary conditions are imposed in two dimensions and deformations of periodic boundaries are allowed in order to reduce the effect of boundaries without giving too much constraint on the symmetry.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 27
End Page 37
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307582
JaLCDOI 10.18926/15405
FullText URL Mem_Fac_Eng_OU_30_2_39.pdf
Author Totsuji, Chieko|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1996-03-29
Volume volume30
Issue issue2
Start Page 39
End Page 43
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307769
JaLCDOI 10.18926/15383
FullText URL Mem_Fac_Eng_OU_30_1_89.pdf
Author Totsuji, Chieko| Sanaka Yoshiaki| Totsuji, Hiroo|
Abstract Based 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 89
End Page 97
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307957
JaLCDOI 10.18926/15379
FullText URL Mem_Fac_Eng_OU_30_1_63.pdf
Author Koshimoto Marcos| Mahmood Zaheed| Kagawa, Yukio|
Abstract Optical 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 63
End Page 73
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307545
JaLCDOI 10.18926/15377
FullText URL Mem_Fac_Eng_OU_30_1_47.pdf
Author Kagawa, Yukio| Sun Yonghao| Mahmood Zaheed|
Abstract Regular boundary element method is employed for the variational formulation of Helmholtz equation that governs the waveguiding problems. Like in the Charge simulation method, in this method, the source points associated with the fundamental solutions are allocated outside the domain so that the singular integrals which occur in the standard boundary element procedure can be avoided. First, the formulation is developed for the two-dimensional scalar Helmholtz problem solving for the axial components of either electric or magnetic fields. The application of the formulation is shown for simple hollow rectangular waveguide and dielectric-slab-loaded rectangular waveguide. Then the formulation is extended for the analysis of dielectric waveguides of open type incorporating axial components of both electric and magnetic fields, for the solution of the propagating modes which are generally of hybrid types. To show the validity and quality of the formulation, it is applied to a circular step-index optical waveguide and a dielectric rectangular waveguide. Very close agreements have been found when the solutions are compared with the ones obtained by different methods. One distinct merit of the extended formulation is that it has been fixed to suppress the spurious solutions which are encountered while solved by the conventional boundary element method.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 47
End Page 62
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307187
JaLCDOI 10.18926/15365
FullText URL Mem_Fac_Eng_OU_30_1_1.pdf
Author Dong Liu| Kajihara, Yasuhiro| Osaki, Hirokazu| Munesawa, Yoshiomi|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-12-28
Volume volume30
Issue issue1
Start Page 1
End Page 7
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307491