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JaLCDOI 10.18926/19956
FullText URL Mem_Fac_Eng_OU_44_24.pdf
Author Kanatani, Kenichi| Sugaya Yasuyuki|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 24
End Page 31
ISSN 1349-6115
language English
File Version publisher
NAID 120002309159
JaLCDOI 10.18926/19955
FullText URL Mem_Fac_Eng_OU_44_13.pdf
Author Kanatani, Kenichi| Sugaya Yasuyuki|
Abstract A new numerical scheme is presented for computing strict maximum likelihood (ML) of geometric fitting problems having an implicit constraint. Our approach is orthogonal projection of observations onto a parameterized surface defined by the constraint. Assuming a linearly separable nonlinear constraint, we show that a theoretically global solution can be obtained by iterative Sampson error minimization. Our approach is illustrated by ellipse fitting and fundamental matrix computation. Our method also encompasses optimal correction, computing, e.g., perpendiculars to an ellipse and triangulating stereo images. A detailed discussion is given to technical and practical issues about our approach.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 13
End Page 23
ISSN 1349-6115
language English
File Version publisher
NAID 120002309170
JaLCDOI 10.18926/19954
FullText URL Mem_Fac_Eng_OU_44_7.pdf
Author Maetani Noriaki| Kurose Tomoyuki| Tsuruta, Kenji|
Abstract The lens effect of acoustic waves in a two-dimensional (2D) phononic crystal is studied by numerical simulation based on the finite-difference time-domain (FDTD) method. We calculate the phonon band structure of 2D phononic crystals, consisting of metal cylinders placed periodically in water. Lens effect is observed by the negative refraction of acoustic waves, which results in refocusing of the waves at the point outside the crystal. To increase the focal intensity, we introduce a 2D phononic crystal shield with a different composition of material, which returns the incident waves back to the lens via the perfect reflection. Also, the dependence on filling fraction of metal in the crystal is studied.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 7
End Page 12
ISSN 1349-6115
language English
File Version publisher
NAID 120002309019
JaLCDOI 10.18926/19953
FullText URL Mem_Fac_Eng_OU_44_1.pdf
Author Nagai Shinji| Umeda Ryosuke| Tsuruta, Kenji|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 1
End Page 6
ISSN 1349-6115
language English
File Version publisher
NAID 120002309117
JaLCDOI 10.18926/19692
FullText URL Mem_Fac_Eng_OU_33_2_111.pdf
Author Fujihara Yutaka| Munesawa, Yoshiomi| Osaki, Hirokazu|
Abstract Our 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 111
End Page 119
ISSN 0475-0071
language English
File Version publisher
NAID 120002309035
JaLCDOI 10.18926/19689
FullText URL Mem_Fac_Eng_OU_33_2_105.pdf
Author Tokunaga Shuichi| Osaki, Hirokazu|
Abstract This 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 105
End Page 110
ISSN 0475-0071
language English
File Version publisher
NAID 120002309175
JaLCDOI 10.18926/19684
FullText URL Mem_Sch_Eng_OU_21_2_47.pdf
Author Taniguchi, Takeo| Tsurumi Yasuo|
Abstract The aim of this paper is to propose new automatic mesh generator for the finite element analysis of threedimensional structures consisted of plates and beams. The strategy of the proposed one is as followings; Firstly, subdivide the structure into two-dimensional and one-dimensional structural components. Secondly, generate mesh pattern for each of them, and finally combine them so that they reconstruct the original configuration. By using the proposed method the modeling of, for example, steel bridge structures for Finite Element Analysis is easily and also fastly completed. Some examples of the application of the proposed method are presented, and from the examination of the results further important informations for the design of better method are also given in this paper.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1987-03-05
Volume volume21
Issue issue2
Start Page 47
End Page 63
ISSN 0475-0071
language English
File Version publisher
NAID 120002309157
JaLCDOI 10.18926/19682
FullText URL Mem_Fac_Eng_OU_33_2_91.pdf
Author Munesawa, Yoshiomi| Osaki, Hirokazu| Kajihara, Yasuhiro|
Abstract In 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 91
End Page 96
ISSN 0475-0071
language English
File Version publisher
NAID 120002309052
JaLCDOI 10.18926/19680
FullText URL Mem_Fac_Eng_OU_33_2_85.pdf
Author Yamada, Mitsuru| Osaki, Hirokazu|
Abstract We 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 85
End Page 89
ISSN 0475-0071
language English
File Version publisher
NAID 120002309120
JaLCDOI 10.18926/19677
FullText URL Mem_Fac_Eng_OU_33_2_79.pdf
Author Osaka, Akiyoshi| Hayakawa, Satoshi| Koyano Keiko| Tsuru, Kanji|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 79
End Page 84
ISSN 0475-0071
language Japanese
File Version publisher
NAID 120002309011
JaLCDOI 10.18926/19674
FullText URL Mem_Fac_Eng_OU_33_2_71.pdf
Author Tsuruta, Kenji| Totsuji, Hiroo| Totsuji, Chieko|
Abstract A parallel tight-binding molecular dynamics with an order-N [O(N))] algorithm is implemented to perform large-scale simulation of nanostructured materials. The algorithm is based on the Fermi-operator expansion of an electronic energy and force, and we present its basic formalisms. Accuracy necessary for molecular-dynamics simulations can be obtained by a proper truncation in the expansion. Parallel efficiency on a parallel PC cluster shows nearly ideal scaling behavior with respect to the number of processors. Applicability of the method to a silicon-carbide system is examined.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 71
End Page 77
ISSN 0475-0071
language English
File Version publisher
NAID 120002309027
JaLCDOI 10.18926/19673
FullText URL Mem_Fac_Eng_OU_33_2_61.pdf
Author Totsuji, Hiroo| Tsuruta, Kenji| Totsuji, Chieko|
Abstract The behavior of multicomponent plasmas in the Penning-Malmberg traps is discussed with the parameters corresponding to experiments with antiprotons and cryogenic electrons. The relaxation times for the energy transfer antiprotons to electrons and between parallel and perpendicular components of electrons are estimated. It is shown that, depending on the values of parameters, both the former and the latter can be the bottleneck in the cooling process.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 61
End Page 69
ISSN 0475-0071
language English
File Version publisher
NAID 120002309106
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 10.18926/19666
FullText URL Mem_Fac_Eng_OU_33_2_45.pdf
Author Yamada Nobuya| Oka, Hisao|
Abstract It 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 45
End Page 50
ISSN 0475-0071
language English
File Version publisher
NAID 120002309193
JaLCDOI 10.18926/19663
FullText URL Mem_Fac_Eng_OU_33_2_39.pdf
Author Yanagi Makoto| Oka, Hisao|
Abstract The 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 39
End Page 44
ISSN 0475-0071
language English
File Version publisher
NAID 120002309185
JaLCDOI 10.18926/19660
FullText URL Mem_Fac_Eng_OU_33_2_25.pdf
Author Song Baoyin| Inaba, Hideo| Horibe, Akihiko|
Abstract A 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.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 25
End Page 37
ISSN 0475-0071
language English
File Version publisher
NAID 120002308992
JaLCDOI 10.18926/19657
FullText URL Mem_Fac_Eng_OU_33_2_19.pdf
Author Yamamoto, Kyoji| Jiao Xuecheng| Jiao Xuezhen|
Abstract A new type of hydrocyclone with a perforated inner cylinder is tested experimentally to study its performance for liquid-solid separation. The size of the cyclone is small so that it may be effective for small particle separation. Two types of the inner cylinder were made : the one has 39.5% void fraction of the perforated surface and the other has 73.5% . The mean particle diameter is 4.5 μ m. It is found that the pressure loss of the cyclone with the inner cylinder is reduced by about 25% compared with that of the ordinary type. The new type cyclone has better separation efficiency.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 19
End Page 24
ISSN 0475-0071
language English
File Version publisher
NAID 120002309091
JaLCDOI 10.18926/19654
FullText URL Mem_Fac_Eng_OU_33_2_9.pdf
Author Yamamoto, Kyoji|
Abstract The molecular dynamics study is applied for interaction of the gas molecule with the solid wall to analyse the flow of a rarefied gas between two wall. The wall consisting of Pt molecules is considered to be in a state of physical adsorbates. Two problems are considered : one is the flow problem and the other is the temperature problem. It is found that the tangential momentum accommodation coefficient is about 0.8 when the relative speed ratio of the two walls is unity, while it decreases with increasing Knudsen number when the relative wall speed ratio is 5.0. It shown that the temperature accommodation coefficient is about 0.85 at 300K wall, 0.75 at 450K wall, and 0.69 at 600K wall.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 9
End Page 17
ISSN 0475-0071
language English
File Version publisher
NAID 120002309121
JaLCDOI 10.18926/19648
FullText URL Mem_Fac_Eng_OU_33_2_1.pdf
Author Omura, Yasuhiro| Hida, Moritaka| Sakakibara, Akira| Takemoto, Yoshito|
Abstract Molecular dynamics simulation of nickel crystal under uniaxial tensile and compressive deformation was performed for single nenocrystal model and twinned nanocrystal model composed of 1550 atoms using EAM (embedded atom method) potential with the object of investigating deformation induced phase tranformation (especially twin deformation). In the case of single nanocrystal model, the evolution and development of twin deformation, (111)[11(2)], is observed under compressive loading in [001] direction, whereas either slip or twin deformation is not recognized under tensile loading. In the case of twinned nanocrystal model, twin, (111)[11(2)], decreases and disappears under tensile loading, and develops under compressive loading, It is suggested from the difference of results between single nanocrystal model and twinned nanocrystal model that it is easy for twin to induce local deformation.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 1
End Page 8
ISSN 0475-0071
language English
File Version publisher
NAID 120002309020
JaLCDOI 10.18926/19637
FullText URL Mem_Fac_Eng_OU_32_43.pdf
Author Totsuji, Chieko| Matsubara Takeo|
Abstract Large isotope effects have been observed in various kinds of hydrogen bonded ferro / antiferroelectrics. In clariflying their origin, themodynamic properties of the hydrogen bond are of essential importance. Two numerical methods are applied to analyze the model for isolated hydrogen bond at finite temperatures and the results of excited energy levels of proton or deuteron are examined. It is found that the second excited state is not far enough from the first excited state to be neglected discussing themodynamic properties of hydrogen especially in their ordered states.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1998-04-20
Volume volume32
Issue issue1-2
Start Page 43
End Page 54
ISSN 0475-0071
language English
File Version publisher
NAID 120002309098