JaLCDOI 10.18926/17853
FullText URL Mem_Fac_Eng_OU_43_113.pdf
Author Sakemi, Yumi| Kato, hidehiro| Nogami, Yasuyuki| Morikawa, Yoshikawa|
Abstract Barreto–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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 113
End Page 116
ISSN 1349-6115
language English
File Version publisher
NAID 120002308945
JaLCDOI 10.18926/17822
FullText URL Mem_Fac_Eng_OU_43_1.pdf
Author Shimizu, Kenichi| Torii, Tashiyuki| Ishida, Koki|
Abstract Using 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 1
End Page 7
ISSN 1349-6115
language English
File Version publisher
NAID 120002308710
JaLCDOI 10.18926/15456
FullText URL Mem_Fac_Eng_OU_28_2_21.pdf
Author Yamamoto, Kyoji| Jiao Xuezhen|
Abstract An 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1994-03-15
Volume volume28
Issue issue2
Start Page 21
End Page 31
ISSN 0475-0071
language English
File Version publisher
NAID 120002307575
JaLCDOI 10.18926/15363
FullText URL Mem_Fac_Eng_OU_34_39.pdf
Author Hayakawa, Satoshi| Shirosaki, Yuki| Yabuta, Takeshi| Tsuru, Kanji| Ohtsuki Chikara| Osaka, Akiyoshi|
Abstract Silicone 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).
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2000-03-27
Volume volume34
Issue issue1-2
Start Page 39
End Page 43
ISSN 0475-0071
language English
File Version publisher
NAID 120002308019
JaLCDOI 10.18926/47026
FullText URL mfe_36_2_061_066.pdf
Author Yamagiwa, Masashi| Namba, Akitoshi| Akao, Tetsuyuki| Mizuki, Eiichi| Ohba, Michio| Sakai, Hiroshi|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-03
Volume volume36
Issue issue2
Start Page 61
End Page 66
ISSN 0475-0071
language English
File Version publisher
NAID 80015582224
JaLCDOI 10.18926/14083
FullText URL Mem_Fac_Eng_OU_41_1_44.pdf
Author Maeno, Ryota| Konishi, Masami| Imai, Jun|
Abstract Petri 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2007-01
Volume volume41
Issue issue1
Start Page 44
End Page 51
ISSN 0475-0071
language English
File Version publisher
NAID 120002308128
JaLCDOI 10.18926/19671
FullText URL Mem_Fac_Eng_OU_33_2_51.pdf
Author Totsuji, Hiroo| Tsuruta, Kenji| Totsuji, Chieko|
Abstract Density 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 51
End Page 59
ISSN 0475-0071
language English
File Version publisher
NAID 120002309192
JaLCDOI 10.18926/15360
FullText URL Mem_Fac_Eng_OU_34_27.pdf
Author Wei, He| Koga, Ryuji| Iokibe, Kengo| Wada, Osami| Toyota, Yoshitaka|
Abstract In 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.
Keywords Mie lidar Asian dust (KOSA) depolarization ratio backscattering ratio range normalized
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2000-03-27
Volume volume34
Issue issue1-2
Start Page 27
End Page 37
ISSN 0475-0071
language English
File Version publisher
NAID 120002307539
JaLCDOI 10.18926/15404
FullText URL Mem_Fac_Eng_OU_27_2_41.pdf
Author Prokop Jiri| Myojin Sho|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 41
End Page 58
ISSN 0475-0071
language English
File Version publisher
NAID 120002307241
JaLCDOI 10.18926/15370
FullText URL Mem_Fac_Eng_OU_27_2_73.pdf
Author Kroumov Valeri T.| Inoue, Akira| Masuda, Shiro|
Abstract This 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-03-25
Volume volume27
Issue issue2
Start Page 73
End Page 85
ISSN 0475-0071
language English
File Version publisher
NAID 120002307731
JaLCDOI 10.18926/15437
FullText URL Mem_Fac_Eng_OU_28_1_51.pdf
Author Kohno, Iichiro| Tanabe Kazuyasu| Tomita Takemitsu|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 51
End Page 59
ISSN 0475-0071
language English
File Version publisher
NAID 120002307254
JaLCDOI 10.18926/15467
FullText URL Mem_Fac_Eng_OU_23_1_61.pdf
Author Yamamoto, Yoshitake| Yamamoto, Tatsuma|
Abstract Skin 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1988-11-22
Volume volume23
Issue issue1
Start Page 61
End Page 68
ISSN 0475-0071
language English
File Version publisher
NAID 120002307322
JaLCDOI 10.18926/15483
FullText URL Mem_Fac_Eng_OU_24_1_107.pdf
Author Kohno, Iichiro| Nishigaki, Makoto| Takeshita, Yuji|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1989-11-29
Volume volume24
Issue issue1
Start Page 107
End Page 114
ISSN 0475-0071
language English
File Version publisher
NAID 120002307749
JaLCDOI 10.18926/15498
FullText URL Mem_Fac_Eng_OU_25_1_99.pdf
Author Nishigaki, Makoto| Takeshita, Yuji| Kono, Iichiro|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 99
End Page 109
ISSN 0475-0071
language English
File Version publisher
NAID 120002307452
JaLCDOI 10.18926/15380
FullText URL Mem_Fac_Eng_OU_35_197.pdf
Author Nogami, Yasuyuki| Morikawa, Yoshitaka|
Abstract Modern 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.
Keywords finite field minimal polynomial irreducible polynomial higher degree trace trace cryptography
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 197
End Page 205
ISSN 0475-0071
language English
File Version publisher
NAID 120002307992
JaLCDOI 10.18926/15371
FullText URL Mem_Fac_Eng_OU_35_163.pdf
Author Uchiyama Hiromitsu| Miyazaki Satoshi| Osaki, Hirokazu| Kajihara, Yasuhiro| Munesawa, Yoshiomi| Matsuki Katsunori|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 163
End Page 168
ISSN 0475-0071
language English
File Version publisher
NAID 120002307229
JaLCDOI 10.18926/15269
FullText URL Mem_Fac_Eng_OU_35_47.pdf
Author Doumae, Yukihiro| Konishi, Masami| Imai, Jun| Asada, Hideki| Kitamura, Akira|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 47
End Page 51
ISSN 0475-0071
language English
File Version publisher
NAID 120002307181
JaLCDOI 10.18926/15385
FullText URL Mem_Fac_Eng_OU_27_1_1.pdf
Author Uno, Yoshiyuki| Kubota, Shin-ichiro| Nakajima, Toshikatsu| Ogata, Kojiro| Tada, Nobuhiko|
Abstract Direct 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-11-25
Volume volume27
Issue issue1
Start Page 1
End Page 10
ISSN 0475-0071
language English
File Version publisher
NAID 120002307702
JaLCDOI 10.18926/15378
FullText URL Mem_Fac_Eng_OU_35_191.pdf
Author Yoshida Takanobu| Munesawa, Yoshiomi| Osaki, Hirokazu| Kajihara, Yasuhiro| Ohta Kazuharu|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 191
End Page 196
ISSN 0475-0071
language English
File Version publisher
NAID 120002307328
JaLCDOI 10.18926/17826
FullText URL Mem_Fac_Eng_OU_43_8.pdf
Author Umeda Ryosuke| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract Metamaterial 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 8
End Page 15
ISSN 1349-6115
language English
File Version publisher
NAID 120002308833