JaLCDOI 10.18926/14053
FullText URL Mem_Fac_Eng_OU_42_1.pdf
Author Asatani Jun| Koumoto, Takuya| Toru Fujiwara| Tadao Kasami|
Abstract Two typical examples, the (32, 21, 6) and (64, 45, 8) extended code of primitive permuted BCH codes, are considered. The sets of minimum weight codewords are analyzed in terms of Boolean polynomial representation. They are classied by using their split weight structure with respect to the left and right half trellis sections, and for each class, the standard form is presented. Based on the results, we can generate a proper list of the minimum weight codewords of the codes.
Keywords Boolean polynomial representation extended BCH codes minimum weight codewords binary shift invariance property
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 1
End Page 9
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308333
JaLCDOI 10.18926/14055
FullText URL Mem_Fac_Eng_OU_42_10.pdf
Author Kanatani, Kenichi|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 10
End Page 17
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308447
JaLCDOI 10.18926/14056
FullText URL Mem_Fac_Eng_OU_42_18.pdf
Author Kanatani, Kenichi| Yasuyuki Sugaya|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 18
End Page 35
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308468
JaLCDOI 10.18926/14060
FullText URL Mem_Fac_Eng_OU_42_53.pdf
Author Chai Hong| Totsuji, Hiroo|
Abstract In order to transfer quantum information, the use of spin chains has been proposed and their transfer characteristics have been analyzed. As one of the latter, the maximum of the transfer probability over sufficiently long time period is often considered important and some examples with high maximum values have been given. In these examples, the coupling between neighboring spins are tuned so as to attain high efficiency. In this article, we discuss the effect of noise on the values of coupling constant. As a result, we propose a system where the efficiency is high and also the effect of noise is small.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 53
End Page 55
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308635
JaLCDOI 10.18926/14086
FullText URL Mem_Fac_Eng_OU_41_1_63.pdf
Author Kanatani, Kenichi| Sugaya, Yasuyuki|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2007-01
Volume volume41
Issue issue1
Start Page 63
End Page 72
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308585
JaLCDOI 10.18926/14087
FullText URL Mem_Fac_Eng_OU_41_1_73.pdf
Author Kanatani, Kenichi|
Abstract A rigorous accuracy analysis is given to various techniques for estimating parameters of geometric models from noisy data for computer vision applications. First, it is pointed out that parameter estimation for vision applications is very different in nature from traditional statistical analysis and hence a different mathematical framework is necessary in such a domain. After general theories on estimation and accuracy are given, typical existing techniques are selected, and their accuracy is evaluated up to higher order terms. This leads to a “hyperaccurate” method that outperforms existing methods.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2007-01
Volume volume41
Issue issue1
Start Page 73
End Page 92
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308410
JaLCDOI 10.18926/14122
FullText URL Mem_Fac_Eng_OU_40_1_44.pdf
Author Sugaya, Yasuyuki| Kanatani, Kenichi| Kanazawa, Yasushi|
Abstract Dense 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 44
End Page 52
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308593
JaLCDOI 10.18926/14123
FullText URL Mem_Fac_Eng_OU_40_1_53.pdf
Author Kanatani, Kenichi| Sugaya, Yasuyuki| Hanno Ackermann|
Abstract In order to reconstruct 3-D Euclidean shape by the Tomasi-Kanade factorization, one needs to specify an affine camera model such as orthographic, weak perspective, and paraperspective. We present a new method that does not require any such specific models. We show that a minimal requirement for an affine camera to mimic perspective projection leads to a unique camera model, which we call a symmetric affine camera, which has two free functions. We determine their values from input images by linear computation and demonstrate by experiments that an appropriate camera model is automatically selected.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 53
End Page 63
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308664
JaLCDOI 10.18926/14124
FullText URL Mem_Fac_Eng_OU_40_1_64.pdf
Author Kanatani, Kenichi|
Abstract This article summarizes recent advancements of the theories and techniques for 3-D reconstruction from multiple images. We start with the description of the camera imaging geometry as perspective projection in terms of homogeneous coordinates and the definition of the intrinsic and extrinsic parameters of the camera. Next, we described the epipolar geometry for two, three, and four cameras, introducing such concepts as the fundamental matrix, epipolars, epipoles, the trifocal tensor, and the quadrifocal tensor. Then, we present the self-calibration technique based on the stratified reconstruction approach, using the absolute dual quadric constraint. Finally, we give the definition of the affine camera model and a procedure for 3-D reconstruction based on it.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 64
End Page 77
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308332
JaLCDOI 10.18926/14149
FullText URL Mem_Fac_Eng_39_1_40.pdf
Author Al-Sehaim, Sulaiman| Konishi, Masami| Nose, Kazuo|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2005-01
Volume volume39
Issue issue1
Start Page 40
End Page 45
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308505
JaLCDOI 10.18926/14153
FullText URL Mem_Fac_Eng_39_1_56.pdf
Author Sugaya, Yasuyuki| Kanatani, Kenichi|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2005-01
Volume volume39
Issue issue1
Start Page 56
End Page 62
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308594
JaLCDOI 10.18926/14155
FullText URL Mem_Fac_Eng_39_1_63.pdf
Author Kanatani, Kenichi|
Abstract Geometric fitting is one of the most fundamental problems of computer vision. In [8], the author derived a theoretical accuracy bound (KCR lower bound) for geometric fitting in general and proved that maximum likelihood (ML) estimation is statistically optimal. Recently, Chernov and Lesort [3] proved a similar result, using a weaker assumption. In this paper, we compare their formulation with the author’s and describe the background of the problem. We also review recent topics including semiparametric models and discuss remaining issues.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2005-01
Volume volume39
Issue issue1
Start Page 63
End Page 70
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308366
JaLCDOI 10.18926/15164
FullText URL Mem_Fac_Eng_OU_35_41.pdf
Author Kuroboshi, Manabu| Tanaka, Muneaki| Kishimoto, Suguru| Goto, Kentaro| Tanaka, Hideo|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 41
End Page 46
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307948
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 10.18926/15346
FullText URL Mem_Fac_Eng_OU_35_9.pdf
Author Abe, Takeji| Tsuboi, Tomoaki|
Abstract The evaluation of microscopic inhomogeneity of polycrystalline aluminum is performed by measuring the hardness in respective grains. The recently developed ultra-micro hardness tester is used and the effects of the test pattern, the indentation load and the indenting velocity are examined. Then, the relationship between the increase in the hardness caused by the work hardening and the deformation of respective grains are statistically investigated. The hardness testing mode in which the initial load is applied before the onset of measurement gives more stable results than the testing mode without the initial load. The test condition with the indentation load of 9.8mN and the indentation velocity of 0.2 μm/sec seems to be optimum and gives the least dispersion of the measured values in grains. It is shown that the hardness values of respective grains in polycrystalline aluminum as well as their dispersion increase with the applied plastic strain. Discussion is made on the microscopic deformation behavior of polycrystalline aluminum.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 9
End Page 19
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307825
JaLCDOI 10.18926/15354
FullText URL Mem_Fac_Eng_OU_34_1.pdf
Author Song Baoyin| Inaba, Hideo| Horibe, Akihiko| Takahashi Takashi|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2000-03-27
Volume volume34
Issue issue1-2
Start Page 1
End Page 12
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307686
JaLCDOI 10.18926/15356
FullText URL Mem_Fac_Eng_OU_34_13.pdf
Author Sakakibara, Akira| Tanimoto, Tadashi| Matsushima, Takahisa| Hosokawa, Norio| Kanadani, Teruto|
Abstract Repeated 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2000-03-27
Volume volume34
Issue issue1-2
Start Page 13
End Page 17
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307815
JaLCDOI 10.18926/15357
FullText URL Mem_Fac_Eng_OU_35_53.pdf
Author Kim Tae Yong| Kagawa, Yukio|
Abstract Fresnel 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 53
End Page 61
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307849
JaLCDOI 10.18926/15362
FullText URL Mem_Fac_Eng_OU_35_97.pdf
Author Yamasaki, Susumu| Kurose, Yoshinori|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 97
End Page 135
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307812
JaLCDOI 10.18926/15364
FullText URL Mem_Fac_Eng_OU_35_137.pdf
Author Sakiyama, Takaharu| Yoshimi, Tsuyoshi| Miyake, Akira| Umeoka, Midori| Tanaka, Atsushi| Ozaki, Sho| Nakanishi, Kazuhiro|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-03-27
Volume volume35
Issue issue1-2
Start Page 137
End Page 146
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307705