| 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 | 10.18926/19682 |
|---|---|
| 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 |
| JaLCDOI | 10.18926/19636 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_32_23.pdf |
| Author | Totsuji, Hiroo| Kishimoto, Tokunari| Totsuji, Chieko| |
| Abstract | Parameters characterizing the structure ot confined Yukawa system are estimated for 'dusty plasmas', clouds of charged macroscopic particles formed near the boundary between plasma and the sheath and leviated by negatively biased electrode. When we have dust particles with different ratios of charge to mass, they form a two-dimensional Yukawa mixture or separate two-dimensional one-companent Yukawa systems, depending on the charge density in the sheath and number density of dust particles. In order to provide a basis for numerical simulations on Yukawa mixtures including Coulombic case, we summarize mathematical expressions necessary for molecular dynamics. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1998-04-20 |
| Volume | volume32 |
| Issue | issue1-2 |
| Start Page | 23 |
| End Page | 41 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002309150 |
| JaLCDOI | 10.18926/19634 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_32_15.pdf |
| Author | Mori, Masahiro| Oka, Hisao| |
| Abstract | In a stiffness estimation of living body, an internal structure under the skin influences the measured results. Because a different stiffness of body caused by bones and muscles is obtained. In this paper, by using a measurement system of mechanical impedance, the relations between a viscoelasticity and a distance from the surface of silicone-gel model is calculated. This relation is applied to silicone-gel tumor model and a shape and a viscoelasticity of semi-sphere silicone-gel tumous are estimated. The obtained results are expressed as a reconstructed 3-D image of shape / viscoelasticity. The revised curve-fitting of mechanical impedance and the cancellation of peripheral vibration influence are proposed in order to increase an estimation acccuracy. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1998-04-20 |
| Volume | volume32 |
| Issue | issue1-2 |
| Start Page | 15 |
| End Page | 22 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002309047 |
| JaLCDOI | 10.18926/19632 |
|---|---|
| FullText URL | Mem_Fac_Eng_OU_32_7.pdf |
| Author | Adli| Yamamoto, Yoshitake| |
| Abstract | This paper describes a new measurment method and principle of power line interference elimination in ECG signal using inverse loop and AC power line configuration (APC). First, we considered that magnetic induction effect not only depend on a conductive loop area that formed by shielded wires that connect the object and amplifier but also effect of body area effective must be considered. It is simple and useful because interference can be eliminated to very small value show that the condition and it can be applied in a real ECG signal recording. Second, results show that the contribution of displacement currents into the object especially APC in vertical configuration is smaller than it in other one. Because this method is so easy that it is convenient to be used to understand some aspects of power line interference elimination phenomenon. Hence we expect that this method can be used as one of improvement method in measurement system of ECG signal recording. |
| Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
| Published Date | 1998-04-20 |
| Volume | volume32 |
| Issue | issue1-2 |
| Start Page | 7 |
| End Page | 14 |
| ISSN | 0475-0071 |
| language | English |
| File Version | publisher |
| NAID | 120002309065 |
