Author Faculty of Engineering, Okayama University|
Published Date 2003-03
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Volume volume37
Issue issue2
Content Type Others
JaLCDOI 10.18926/46981
FullText URL mfe_37_2_067_072.pdf
Author Yamagiwa, Masashi| Sakai, Hiroshi|
Abstract An active form of Cry4A is a heterodimer of the 20- and 45-kDa fragments that are derived from the 130-kDa Cry4A protoxin. To investigate the function of these two fragments, several deletion mutants were constructed and expressed in E.coli as the GST (glutathione-S-transferase) fusion proteins. The results of the bioassay against Culex pipiens larvae showed that the interaction of two fragments of Cry4A was necessary for the toxicity, and that the C-terminal 67 amino acids of the 20-kDa fragment corresponding to the helices α4 and α5 were involved in determining the insecticidal activity. Surprisingly the lack of helix α5 did not affect the toxicity to C. pipiens, suggesting that the role of helix α5 of Cry4A was different from that postulated in the case of Cry4A toxins.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 67
End Page 72
ISSN 0475-0071
language 英語
File Version publisher
NAID 80016019143
JaLCDOI 10.18926/46982
FullText URL mfe_37_2_073_087.pdf
Author Nogami, Yasuyuki| Morikawa, Yoshitaka|
Abstract Public 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 73
End Page 87
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015999992
JaLCDOI 10.18926/46983
FullText URL mfe_37_2_089_097.pdf
Author Iokibe, Kengo| Toyota, Yoshitaka| Wada, Osami| Koga, Ryuji|
Abstract Aerosol 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 89
End Page 97
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003457336
JaLCDOI 10.18926/46975
FullText URL mfe_37_2_001_004.pdf
Author Sakakibara, Akira| Kanadani, Teruto|
Abstract Effect of addition of Fe on the occurrence of serration in Al-12mass%Zn alloys was investigated. Specimens aged at 293K for various periods after quenching from various temperatures (T(Q)), 398K to 823K, were tensile-tested at room temperature. Serration occurred more easily and more remarkably with decreasing T(Q) for as-quenched specimens: in the case that T(Q)=448K serration was observed both for the binary and Fe added alloys, while in the case that T(Q)=573K none of the three alloys showed serration. For the binary alloy serration was observed only when the aging period was short enough, but addition of Fe to the binary alloy prolonged the aging period where serration could be recognized. Aging rate measured by hardness was remarkably retarded with the increase of Fe addition. These results confirm the interpretation that the serration in Al-Zn alloy occurs in the early stage of aging where small GP zones or solute clusters are formed.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 1
End Page 4
ISSN 0475-0071
language 英語
File Version publisher
NAID 80016019142
JaLCDOI 10.18926/46976
FullText URL mfe_37_2_005_012.pdf
Author Abe, Takeji| Sato, Takashi|
Abstract Cork is a material that has many characteristics, for instance, light weight, elasticity, insulation against heat, impermeability for liquid, and so forth. There are two types of cork, the natural and the agglomerated corks. In the present paper, compression tests of the natural and the agglomerated cork specimens were carried out. The compression test were done in various directions. Compressive stress was measured by a original compression apparatus, and stress-strain curves were obtained in various directions of the cork specimens. In the natural cork, there are differences between the radial and the non-radial direction. The recovery of dimensions after compression was also studied in respective directions. The structure of the deformed surface was observed by a scanning electron microscope.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 5
End Page 12
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015999990
JaLCDOI 10.18926/46977
FullText URL mfe_37_2_013_027.pdf
Author Shibuta, Taizo| Konishi, Masami| Imai, Jun| Nishi, Tatsushi|
Abstract Nowadays, various kind of reactor furnaces are widely used for the production in industry. The raw materials charged into the furnace generate reaction heat produced by blowing gas. Generally speaking, the reaction heat generated in the furnace is remarkably high. Therefore the occurrence of an inappropriate temperature distribution in the furnace may make damege or serious accident of the furnace. This is the motivation of furnace control. The author is considering the application of studied results to the furnace control of Blast Furnace in steel industry. To the propose, the approximated and simplified Macro Model of the Blast Furnace is constructed which has the function of representation of qualitative characteristics of the furnace in dynamical sense. The furnace temperature, distribution greatly effects both on the producting and the product quality of the furnace. Needless to say, stable furnace operation is indispensable for the economical prosperity of the industry. In this paper, macro simulation of the furnace is developed to support the analysis and design of the furnace control. Using the simulator, the stability and the control characteristics for inner furnace temperature distribtion are analised quantitatively.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 13
End Page 27
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015999991
JaLCDOI 10.18926/46978
FullText URL mfe_37_2_029_044.pdf
Author Imajo, Shuya| Konishi, Masami| Imai, Jun| Nishi, Tatsushi|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 29
End Page 44
ISSN 0475-0071
language 英語
File Version publisher
NAID 80016037880
JaLCDOI 10.18926/46979
FullText URL mfe_37_2_045_060.pdf
Author Xu, Wei| Zhao, Y.| Horikane, T.| Hayata, T.| Tosuji, H.| Kagawa, Y.|
Abstract Resistivity 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 45
End Page 60
ISSN 0475-0071
language 英語
File Version publisher
NAID 80016037881
Author Faculty of Engineering, Okayama University|
Published Date 2003-03
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Volume volume37
Issue issue2
Content Type Others
JaLCDOI 10.18926/46980
FullText URL mfe_37_2_061_066.pdf
Author Vaillancourt, Chico|
Abstract In this case study, I will analyse and discuss the results of a survey concerning motivation towards learning a second language conducted in one Danish high school. The students surveyed were between the ages of 13-18. This section, part two of the study, was conducted in Copenhagen, Denmark. This region of the world was chosen because bilingualism is quite common there and a large portion of the school-aged community is learning a second language and often a third and even a fourth. Denmark, a European country, is different than Canada (Case Study-Part 1.) because it neighbours many countries, which use different mother tongues.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2003-03
Volume volume37
Issue issue2
Start Page 61
End Page 66
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003457333
JaLCDOI 10.18926/46968
FullText URL mfe_37_1_011_014.pdf
Author Totsuji, Chieko| Limant, Muhammad S.| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 11
End Page 14
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015784816
Author Faculty of Engineering, Okayama University|
Published Date 2002-11
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Volume volume37
Issue issue1
Content Type Others
JaLCDOI 10.18926/46967
FullText URL mfe_37_1_001_010.pdf
Author Sotobayashi, Ken| Konishi, Masami| Nishi, Tatsushi| Imai, Jun|
Abstract Auto 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 1
End Page 10
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003457322
JaLCDOI 10.18926/46970
FullText URL mfe_37_1_025_032.pdf
Author Kanazawa, Yasushi| Kanatani, Kenichi|
Abstract We present a new method for detecting point matches between two images without using any combinatorial search. Our strategy is to impose various local and non-local constraints as "soft" constraints by introducing their "confidence" measures via "mean-field approximations". The computation is a cascade of evaluating the confidence values and sorting according to them. In the end, we impose the "hard" epipolar constraint by RANSAC. We also introduce a model selection procedure to test if the image mapping can be regarded as a homography. We demonstrate the effectiveness of our method by real image examples.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 25
End Page 32
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015664456
JaLCDOI 10.18926/46971
FullText URL mfe_37_1_041_049.pdf
Author Sugaya, Yasuyuki| Kanatani, Kenichi|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 41
End Page 49
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003457326
JaLCDOI 10.18926/46972
FullText URL mfe_37_1_051_060.pdf
Author Namba, Akihiro| Toyota, Yoshitaka| Wada, Osami| Koga, Ryuji|
Abstract This paper presents pulse timing control method to reduce electromagnetic emission from multiple signal interconnections. Pulse timing control gives intentional skew between signals. Higher order harmonics are canceled because of the difference of the phase between the signals. Using this property, pulse timing control can reduce the EMI in wide frequency range. In this paper, we show that radiated electromagnetic field from multiple signal lines reduces its intensity to the same level of the field from one line by using pulse timing control. The result of measurement shows that EMI from four differential transmission lines can be reduced more than 9 dB in the 200 MHz to 800 MHz frequency range.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 51
End Page 60
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015683518
JaLCDOI 10.18926/46969
FullText URL mfe_37_1_015_023.pdf
Author Kanatani, Kenichi|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-11
Volume volume37
Issue issue1
Start Page 15
End Page 23
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015664455
Author Faculty of Engineering, Okayama University|
Published Date 2002-11
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Volume volume37
Issue issue1
Content Type Others
JaLCDOI 10.18926/47024
FullText URL mfe_36_2_043_049.pdf
Author Vaillancourt, Chico|
Abstract In this case study, I will analyse and discuss the results of a survey concerning motivation towards learning a second language conducted in four Canadian schools. This section, part one of the study, was conducted in the Sudbury Region of Ontario, Canada. This region of the world was chosen because bilingualism is quite common there and a large portion of the community has learned a second language. Part two will be conducted in the winter of 2002, in Denmark, a European country that neighbours many countries with different mother tongues, I hope to conclude this case study with part three in the summer of 2002, in Japan, a monolingual island nation.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-03
Volume volume36
Issue issue2
Start Page 43
End Page 49
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003497045