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原稿種別: 表紙
p.
Cover1-
発行日: 2002/09/20
公開日: 2017/08/01
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原稿種別: 付録等
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App1-
発行日: 2002/09/20
公開日: 2017/08/01
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原稿種別: 目次
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Toc1-
発行日: 2002/09/20
公開日: 2017/08/01
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金山 寛, 田上 大助, 荒木 隆宏, 久米 宏和
原稿種別: 本文
p.
1-2
発行日: 2002/09/20
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As a preliminary step of large-scale thermal convection analysis, we study effective numerical methods for stationary incompressible nonlinear flow problems. In this paper, we are concerned with the stationary Navier-Stokes equations. To solve the nonlinear equations, the Newton method is used. To compute the problem at each step of the nonlinear iterations, a stabilization technique is introduced. Numerical results show that stabilized technique with the mixed interpolations make convergences fast.
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三好 市朗, 棚橋 隆彦
原稿種別: 本文
p.
3-4
発行日: 2002/09/20
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In this paper, we construct a parallel scheme for incompressible flow using distributed memory multiprocessors with GSMAC-FEM. The feature of the GSMAC-FEM are that it is possible to solve the Possion equation rapidly and that matrix calculation is not needed. In addition, calculation with GSMAC-FEM is conducted element by element, the method is compatible with the domain decomposition method. So, it is expected to be the parallel scheme with high speed, low capacity and high efficiency for large scale calculation. The effectiveness of it is shown through the benchmark problem.
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山崎 美淑, 斉藤 直人, 古谷野 宏一, 笠井 憲一
原稿種別: 本文
p.
5-6
発行日: 2002/09/20
公開日: 2017/08/01
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This paper describes a new estimation method for mean and variances of responses on coupled problem between heat conduction and thermal stress analyses using stochastic finite element method. We applied this method to estimate the reliability of the solder connection part of a multi chip module. As a result, we could recognize the influence of the calorific value in LSI using this method as well as the Monte Carlo method.
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尾田 十八, 坂本 二郎, 木村 繁治, 板垣 省三
原稿種別: 本文
p.
7-8
発行日: 2002/09/20
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Coke is indispensable to obtain iron in the furnace. Each blast furnace company has been improving the coke material and structure for energy-saving and environmental conformity in iron production. High porosity and strength are required for the coke, in order to maintain the breathability against sever loading condition in a blast furnace. In this research, relationship between porous topology and mechanical properties and stress were investigated by using three-dimensional finite-element model of coke considering its porosity.
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河合 剛巨, 瀬川 敦, 尾形 陽一, 矢部 孝
原稿種別: 本文
p.
9-10
発行日: 2002/09/20
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We performed experiment and 3D simulation using CIP-CUP method of skimming phenomenon. According to experiment, we found that there was the optimal range of angle between the bottom of a skipper and water surface. The result can be reproduced with our simulation, which makes a good agreement with experiment. This simulation is a promising resort as the replacement for difficult measurement like a high speed ship.
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中西 為雄, 中野 政身, 小林 宜弘
原稿種別: 本文
p.
11-12
発行日: 2002/09/20
公開日: 2017/08/01
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Numerical simulation of the droplet formation process from the liquid round jet in a Capillary ink jet printer has been conducted. The VOF method along with the continuous surface tension model was applied to calculate the fluid interface. The disturbance derived from the Rayleigh's linear theory was added to the initial jet velocity. In the small surface tension case, nearly uniform droplet was formed in each disturbance cycle. In the large surface tension case, the droplets formed in each disturbance cycle further merge to large droplets.
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井田 真人
原稿種別: 本文
p.
13-14
発行日: 2002/09/20
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This paper investigates the transition frequencies of acoustically couplet gas bubbles by employing a direct numerical simulation technique which is an improved variant of the CIP-CUP method. Recent theoretical studies by the present author showed that gas bubbles interacting in an acoustic field have an undiscovered characteristic frequency, named "transition frequency", which reverses the pulsation phases of bubbles without causing resonance response. In more recent study, it was shown that this characteristic frequency might play an important role in the sign reversal of the secondary Bjerknes force which sometimes result in a stable structure formation of bubbles in an acoustic field. The numerical results presented in this paper have demonstrated that the characteristic frequency indeed exists.
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河本 芳弘, 植草 昌彦, 曄道 佳明, 片岡 真澄
原稿種別: 本文
p.
15-16
発行日: 2002/09/20
公開日: 2017/08/01
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The elucidation of the segregation that arises in the barrel polishing is desired. This study concerns the planetary barrel that simultaneously rotates around the horizontal axis and revolves around vertical axis. Three kinds of particles of different material and sizes were filled into the barrel. Then, using experiments and Discrete Element Method (DEM), the behavior of these particles was investigated. And the characteristics of segregation were also examined by the distribution rates of each of these particles. As the result, it was demonstrated that the particles segregate when three kinds of that were filed even into the rotary barrel.
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清水 文雄, 萩原 洋志, 畠中 清史, 田中 和博, 重藤 博司, 清水 剛
原稿種別: 本文
p.
17-18
発行日: 2002/09/20
公開日: 2017/08/01
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In a flow field including gas and liquid, non-linear phenomena like a swirling vortex occur due to large scale motion of the gas/liquid interface called the free surface. Since large scale deformation of the free surface may obstruct stable supply of water from a tank, it is important to investigate the motion of the free surface. In the present study, two-and three-dimensional computational programs have been constructed to solve free surface in a water tank using C-CUP (Cubic Interpolated Propagation method and Combined Unified Procedure) scheme. To track the large scale motion of the interface, a density function with the transformation of tangent function has been introduced. To verify the programs, several problems in two-and three-dimensions have been simulated. In all cases, the variation of the free surface has been captured successfully.
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西田 青示, 青木 尊之
原稿種別: 本文
p.
19-20
発行日: 2002/09/20
公開日: 2017/08/01
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For computational fluid dynamics including complex material boundaries, we apply an AMR (Adaptive Mesh Refinement) method to describe them accurately. The total grid number is reduced by refining only the region near the surface. The complex material with CAD format is visualized in terms of both the polygons and the voxel surface. The latter is found to show the accurate shape with enough refinement mesh.
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彭 新東, 肖 鋒, 矢部 孝, 谷 啓二, 尹 聖永
原稿種別: 本文
p.
21-22
発行日: 2002/09/20
公開日: 2017/08/01
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Highly accurate advection solver CIP is firstly applied to meteorological model MM5. Improvement of model accuracy and computational performance are observed. In addition to three ideal advective experiments, a case simulations of mesoscale weather system is presented. In comparison with the original Leap-frog scheme in MM5,CIP produced better rainfall position and amount. Realistic spatial distribution of mesoscale systems in successfully described with the CIP scheme.
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渡次 圭, 内藤 和樹, 尾形 陽一, 矢部 孝
原稿種別: 本文
p.
23-24
発行日: 2002/09/20
公開日: 2017/08/01
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A small fish like killifish makes a very sharp turn that is completed within only 0.1-second. Such a quick movement should be important for the fish robot or the high-speed underwater vehicles which are under progress in recent years. In this paper, 3-dimensional fluid dynamical simulation of a sharp turn is performed. Both fluid and the fish are treated as incompressible fluid. For advection term of NS-Equation , we use CIP method that is known as a high-accurate solver of advection equation. From the result, it is confirmed that a fish rotated and accelerated with the pressure generated by its own movement.
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白山 晋, 竹森 恵一, 大和 裕幸
原稿種別: 本文
p.
25-26
発行日: 2002/09/20
公開日: 2017/08/01
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Recently, we can access many kinds of CAE codes. However, selecting a suitable code for the purpose of the effective and efficient computations is easy for users have not knowledge of CAE and no concern about the feature of computer system. In additions, it is quite difficult to determine the appropriate computational parameters even if a well-established CAE code is utilized. In this study, we propose a framework for the selection process of the parameters using distributed resources such as computer, database and knowledge.
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白山 晋, 斎藤 幸二郎, 竹森 恵一, 太田 高志
原稿種別: 本文
p.
27-28
発行日: 2002/09/20
公開日: 2017/08/01
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In CAE, it is quite difficult to select a suitable code and the appropriate computational parameters. We have proposed an idea to support user's selection, and called parameter mining. In this paper, we implement a system of the parameter mining using a procedure of grid computing.
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三村 泰成, 吉村 忍, 古川 知成, 河合 浩志
原稿種別: 本文
p.
29-30
発行日: 2002/09/20
公開日: 2017/08/01
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In this paper, a new parametric optimum design system that is suited for the global computing environment is proposed and the system is discussed using with the parallel finite element analysis. In general, many studies of the parallel distributed calculation are discussed about a collection of computing resources in local area network. On the other hand, the researches of the highly efficient wide area calculation system called "Grid Computing" are done briskly now. At the Grid System, the computing resources connected to the wide area network are recognized as one system by using middleware. Ninf system is a kind of the middleware called Grid RPC. Evaluation procedures in optimization are executed frequently, and each procedure is executable asynchronously. In this study, evaluation procedures are called asynchronously using "Ninf remote procedure call". Each evaluation is calculated by ADVENTURE which is parallel finite element analysis system implemented by MPI.
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大石 篤哉, 冨田 大介, 吉村 忍, 矢川 元基
原稿種別: 本文
p.
31-32
発行日: 2002/09/20
公開日: 2017/08/01
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This paper describes a new local contact searching method using a genetic programming. Generally, contact searching process consists of two phases : a global searching phase for finding nearest node segment pair and a local searching phase for finding exact local coordinates of the contact point in the segment found. In the present method, a genetic programming is utilized for finding an approximating function for local coordinates of the contact point with coordinate values of corresponding nodes. In this paper, the fundamental formulation of the local contact searching method is described in detail and basic performance of the method is demonstrated through sample analyses.
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沖田 俊介, 奥田 洋司, 矢川 元基
原稿種別: 本文
p.
33-34
発行日: 2002/09/20
公開日: 2017/08/01
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Progress of computer in recent years makes an analytical target larger. But it also makes difficult to find or improve bad elements. So, we propose new Meshless method using Inter Connected Neural Network and Free Mesh Method (FMM) which is one of Meshless method based on Finite Element Method (FEM) to calculate with a few bad elements. Because Inter connected Neural Network behave asynchronously, this method is considered to have high adaptability to asynchronous analysis. In this paper, we make the state similar to asynchronous analysis of parallel analysis with single computer and examine possibility of asynchronous analysis in this method.
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吉野 京太郎, 稲葉 正和, 藤澤 智光, 矢川 元基
原稿種別: 本文
p.
35-36
発行日: 2002/09/09
公開日: 2017/08/01
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Crack analysis using the improved free mesh method (FMM) is presented. In the fracture mechanics, the computational grids must be refined frequently with propagation of cracks. However, it is difficult to carry out mesh generation on parallel computers in general. In the present method, the finite element mesh is generated in a local area around each node, so that both of pre-processing and main-processing can be divided into multiple processors in terms of nodes. The local elements generated by the proposed algorithm are founded on the constrained Delaunay triangulation, so that the mesh even for severe shapes such as cracks can be generated in a local manner. A numerical example shows that sharp crack propagation can successfully be analyzed by the present method.
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稲葉 正和, 藤澤 智光, 矢川 元基
原稿種別: 本文
p.
37-38
発行日: 2002/09/20
公開日: 2017/08/01
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A node-based parallel mesh generation technique based on the free mesh method (FMM) is presented. The technique is featured by a node-by-node algorithm and it is quite suitable for massively parallel computing. The finite element mesh is generated in a local area around each node by searching neighboring nodes using the multilevel buckets. Local elements generated by the present method are founded on the constrained Delaunay triangulation, so that the mesh even for severe shapes such as cracks can be generated in a local manner. Furthermore, the inconsistency in satellite elements caused by degeneracy of nodal distribution can be avoided by the local index method presented in this paper.
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土田 潤, 伊東 聰, 藤澤 智光, 矢川 元基
原稿種別: 本文
p.
39-40
発行日: 2002/09/20
公開日: 2017/08/01
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The edge tone, which is the sounding source of air-reed instruments is simulated based on computational fluid dynamics using the free mesh method. The air-reed instrument is a kind of woodwind instruments, which does not have any mechanically oscillating parts. In the past, considerable amount of scientific researches have been made on the woodwind instruments from an acoustic point of view. However, all those studies are founded on acoustic assumptions such as existence of the source of sound. In this study, we attempt to elucidate the source of sound, which is considered to be an essential factor in the timbre of musical instruments. Since large computational grids are required for capturing minute change of pressure, a massively parallel supercomputer HITACHI SR8000 is employed for the simulation. The computational results are compared to the Brown's experimental equation, and basic accuracy of the computation is confirmed.
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益田 泰輔, 中西 義孝, 日垣 秀彦
原稿種別: 本文
p.
41-42
発行日: 2002/09/20
公開日: 2017/08/01
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It has been proposed that the oxide film on metallic bearing surfaces improves its corrosion resistance and decreases wear. Influence of dissolved oxygen in the lubricating liquid containing principal constituents of synovial fluid on wear characteristics of Co-Cr-Mo alloy used in a metal-on-metal artificial hip joint has been investigated by using a pin-on-plate wear machine. Decrease in the concentration of dissolved oxygen caused the wear to decrease, in which the concentration was approximately the same value in vivo. The material properties of the bearing surface are probably controlled by the oxygen concentration. The friction coefficient increased in the low oxygen concentration. This indicates that the decrease in the oxygen concentration makes the adhesion between the bearing surfaces increase. The increase in the adhesion leads to the high frictional force. The high adhesion and frictional force affected work hardening and refinement of the bearing surface, so that the wear was decreased.
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スウーチュー アネタ ニコレタ, 岩壺 卓三, 松田 光正, 西野 孝
原稿種別: 本文
p.
43-44
発行日: 2002/09/20
公開日: 2017/08/01
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This paper presents an experimental investigation of an artificial knee joint with tibial poro-elastic-hydrated cartilage and micro-pocket-covered femoral head. Material of the tibial cartilage is polyvinyl alcohol hydrogel (PVAH), produced by the cyclic freezing/thawing and annealing methods. Femoral head is considered as a circular plate made in stainless steel. Wear experiments are performed on a knee motion simulator, which provides an ISO/WD-14243 anterior-posterior tibial displacement pattern. Variation of the wear factor versus number of walking cycles is presented for PVAH layers with different water contents. Results obtained for a micro-pocket-covered femur are compared with those found in the reference case of a smooth femur.
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下戸 健, 末次 真人, 日垣 秀彦, 中西 義孝, 三浦 裕正, 馬渡 太郎, 岩本 幸英
原稿種別: 本文
p.
45-46
発行日: 2002/09/20
公開日: 2017/08/01
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In vivo measurement of 3-D kinematics of total knee arthroplasty (TKA) is expected, as one of important technique for design of the artificial knee joint in future generation. Therefore, in vitro analysis of polyethylene wear, contact pressure are possible in femorotibial joint and fomoropatellar joint. The study aimed to develop the full six degrees of freedom (DOF) motion simulator for the artificial knee joint using parallel link 6-DOF actuator and air survo cylinders. In this report, we evaluate the method of simulation and usefulness of simulator. The tibial insert was mounted on the 6-DOF actuator and controled internal/external and abduction/adduction rotation, and lateral/medial and anterior/posterior translation. The femoral component was mounted on a jig and control flexion/extension rotation and loading by two air survo cylinders. The contact area and the contact pressure were measured for 2 types of TKA by a tactile sensor under a typical gait condition.
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富岡 淳, 元久保 和宏, 渡邉 久芳
原稿種別: 本文
p.
47-48
発行日: 2002/09/20
公開日: 2017/08/01
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It is well known that red blood cells (RBCs) are suffered from chronic stresses in systemic circulation. The objective of this study is to clarify the effect of the aging of RBCs on the ability of aggregation, fragility and deformability. Initially, RBCs age fractionation was performed by using a high-speed centrifugation, then young and aged RBCs were suspended in plasma to adjust the hematocrit value of 40 [%]. After this pretreatment, the viscosity was measured by a cone-plate type viscometer, and the hemolysis test was carried out by a seesaw type shaker. Results from these experiments showed that the viscosity was increased under the condition of all shear zones, and the hemolytic value was increased twice as the aging. The data obtained in this study indicated that the ability of aggregation of RBCs was increased and the deformability of RBCs' membrane got lower with the aging. Furthermore, it was exhibited that the fragility of RBCs' membrane was increased with the aging.
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富岡 淳, 渡邉 久芳, 植原 規貴, 田所 忠泰
原稿種別: 本文
p.
49-50
発行日: 2002/09/20
公開日: 2017/08/01
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A critical issue facing the development of medical devices such as rotary blood pumps is preventing seizure of bearing gaps. Seizure due to occlusion of the bearing gaps was hypothesized to be related to the adhesion and aggregation of blood plasma. The purpose of this research is acquiring high temperature rheological property of plasma to prevent seizure of bearing gaps of medical devices. Cone and plate viscometer used in this studies. Share rate 383 [1/s] is applied to plasma upon exposure to temperature between 35 [℃] and 55 [℃] up to 6 hours and measure the viscosity every one hour. Additionally, plasma is set five kinds of temperature and let stand for 6 hours in the test tubes and observed the condition every one hour. As the results of experiments, the viscosity did not change at 35 [℃] and 45 [℃], and arrived at the measurement marginal ground within four hours at more than 48 [℃]. As results of observing plasma in the test tubes, plasma did not change at 35 [℃] and at 45 [℃], and precipitation was observed 3 hours after at 49 [℃], and it precipitated white immediately at 50 [℃] and 55 [℃] and the amount of precipitation increased with time progress. As the results of these experiments, there is a possibility that seizure turn up in more than 48 [℃]. In designing bearing gaps of medical devises, it should be designed less than 45 [℃] in gaps to avoid seizure.
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富岡 淳, 深石 晃, 大場 教司
原稿種別: 本文
p.
51-52
発行日: 2002/09/20
公開日: 2017/08/01
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Magnetic fluid seals are used in a wide variety of gas and dust sealing applications. However, it is difficult to seal for liquid because of its characteristics. The objective of this study is to clarify the characteristics of magnetic fluid seals for liquid, especially for blood. Sealing pressure test, durability test, and hemolysis test have been conducted for this seal. In this study, magnetic fluid, sealing fluid, eccentricity ratio, revolution speed were selected as parameters. As results of the tests, it has been found that properties of magnetic fluid seal depend on the solvent and the saturation magnetization of magnetic fluid. Therefore, the selection of magnetic fluid is important for this seal. It also has been found that eccentricity ratio of the shaft caused harmful effect for seal properties. In conclusion, it has been showed that magnetic fluid seals could be possibly used in medical instruments such as rotary blood pumps.
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富岡 淳, 橋爪 毅大
原稿種別: 本文
p.
53-54
発行日: 2002/09/20
公開日: 2017/08/01
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A centrifugal blood pump has been developed as an implantable left ventricular assist device. A newly designed mechanical seal with a recirculating cooling water system is used for the shaft seal. The mechanical seal separate cooling water and blood in the sealing face. The objective of this study is to establish the measuring method of bidirectional leakage of the sealed fluid and the cooling-water through the sealing face, especially when blood is used as the sealed fluid. The leakage of the blood to the cooling-water side was measured by the atomic emission spectroscopy. The leakage of the cooling-water to the blood side was measured by using the atomic absorption spectroscopy, by using the standard addition method, by the correction of hemolysis caused by leakage of the cooling water. As the results of the experiments, the leakage rate of both the cooling water and the blood were below 0.4 [ml/6h]. Therefore, the mechanical seal performed acceptably well to support its use in the centrifugal blood pump.
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中西 義孝, 日垣 秀彦, 宮川 浩臣
原稿種別: 本文
p.
55-56
発行日: 2002/09/20
公開日: 2017/08/01
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A new approach to gait analysis has been proposed in order to clarify influences of flooring materials on level walking by using a specially designed, equilateral-triangular force plate, which has many advantages over commercial plates, and which measures the three orthogonal components of the ground reaction force as well as the plantar friction as the frictional coefficient between the flooring material and the sole. The time history of the plantar friction had two peaks in one step, which was synchronous with that of the vertical ground reaction force. The plantar friction increased extremely at heel contact and toe off, the value sometimes exceeding 1.0 [-]. The plantar friction between the two peaks was, in contrast, extremely lower, with the value sometimes coming close to zero. This behavior could be explained by the sliding/rolling motion relative to the flooring material and the sole and the adhesive mechanism derived from the human skin.
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中西 義孝, 日垣 秀彦, 三浦 裕正, 岩本 幸英
原稿種別: 本文
p.
57-58
発行日: 2002/09/20
公開日: 2017/08/01
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The purpose of this study is to characterize wear of ultra-high molecular weight polyethylene (UHMWPE) by means of two predominant factors; exposure time and contract pressure, using a UHMWPE pin / Co-Cr-Mo alloy disk test. The wear rate of the UHMWPE under 2.0 or 12.0MPa decreased with the prolongation of the exposure time until it became a constant value, because the disk was replenished with a sufficient adsorbed film of the synovial fluid constituents, which may reduce abrasive wear and adhesive wear. The wear rates under 20.0MPa were not influenced by the exposure time, and were lower than those of 2.0 or 12.0MPa. It is possible that the rubbing motion under the high contact pressure caused the film formation to deteriorate. This indicates the occurrence of adhesion of UHMWPE being formed on the disk at asperity levels. The adhesive UHMWPE may function as a transferred film, which reduces the wear rates.
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大塚 宏一, 中西 義孝, 日垣 秀彦
原稿種別: 本文
p.
59-60
発行日: 2002/09/20
公開日: 2017/08/01
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The purpose of this study was to examine influences of the prolonged stance phase; long stationary loading duration at stance phase, on wear characteristics of an ultra-high molecular weight polyethylene (UHMWPE) cup in an artificial hip joint with a cobalt-chromium-molybdenum (Co-Cr-Mo) alloy ball. Lubricant was a water-based liquid, and it contained principal constituents in synovial fluid. The wear of UHMWPE cup with the prolonged stance phase (interruption cycle) was lower than that without the prolonged stance phase (sequence cycle). Adhesives material on the bearing surface of Co-Cr-Mo alloy ball was clearly observed in the interruption cycle. Stationary loading without sliding motion such as the prolonged stance phase might cause the exfoliation of adsorbed film of the synovia constituents on the bearing surface to increase. That lead to the transferred film artifacts, which reduced the wear of UHMWPE cup.
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山田 修一, 富田 直秀, 倪 慶清, 柴田 延幸, 増田 稔, 村田 功二
原稿種別: 本文
p.
61-62
発行日: 2002/09/20
公開日: 2017/08/01
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Recently, an explosive flaking-like destruction so-called delamination has been reported in retrieved study for ultra-high molecular weight polyethylene (UHMWPE) knee components. In order to investigate the effect of microscopic substructure on behavior of deformation of UHMWPE, tensile test was carried out under an optical microscope observation. Local strains around boundaries were measured and were calculated by image correlation method.
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柴田 延幸, 富田 直秀, 加藤 功二, 池内 健
原稿種別: 本文
p.
63-64
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
Addition of vitamin E is effective not only to improve wear performance of UHMWPE but also to prevent delamination, a kind of fatigue damage often observed in UHMWPE knee components. In order to investigate the effects of vitamin E addition on the improvement of mechanical characteristics of UHMWPE in molecular level, bi-directional sliding fatigue tests were performed and changes in molecular structure was examined using Fourier Transform Infrared microscope.
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趙 昌熙, 村上 輝夫, 澤江 義則, 中嶋 和弘
原稿種別: 本文
p.
65-66
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
The wear phenomenon of ultra-high molecular weight polyethylene (UHMWPE) in the knee and hip prostheses is one of the major restriction factors on the longevity of these implants. Especially in retrieved knee prostheses with screw holes in the tibial tray, the cold flow into the screw holes is frequently observed on the undersurface of the UHMWPE tibial components. In most retrieved cases, the protruded areas of cold flow on the undersurface were located at the reverse side of the severely worn surface of the UHMWPE tibial component. It appears that the cold flow into screw holes contributes to increase of wear of the UHMWPE tibial components. In this study, knee joint simulator tests were performed to investigate the influence of the cold flow into screw holes on the wear of UHMWPE. Significant cold flow into screw hole was identified in the undersurface of the UHMWPE specimen, and was associated with delamination in the contact area on the opposite side of the specimen.
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日垣 秀彦, 中西 義孝, 三浦 裕正, 河野 勤, 馬渡 太郎, 岩本 幸英
原稿種別: 本文
p.
67-68
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
In joint lubrication, it has been theoretically and experimentally ascertained that fluid film plays a major role in most physiological motion. Intraarticular administration of hyaluronan (HA) has been widely utilized for osteoarthritis (OA) and its viscoelasticity means that it is undoubtedly beneficial as it can supplement the lubricating properties of synovial fluid (SF). Furthermore, boundary lubrication helps to protect the articular surfaces, depending on the severity of the rubbing condition. Recently, dipalmitoil phosphatidylcholine (DPPC), the major lipidic component of SF, has been implicated as a potential boundary lubricant for synovial joints in an in vitro study, and accordingly, the high-molecular weight hyaluronan (HMW-HA) can be expected to have an even more superior effect as a viscosupplement. The purpose of this study is to examine the role of both DPPC and HMW-HA with regard to joint lubrication and their preventive effects on OA.
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日垣 秀彦, 中西 義孝, 三浦 裕正, 河野 勤, 馬渡 太郎, 岩本 幸英
原稿種別: 本文
p.
69-70
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
Hyaluronic acid (HA) has been examined as both a biochemical agent and a physiological barrier to prevent adhesion, and the effectiveness of exogenous administration of sodium HA for adhesion prevention in the case of flexor tendons has been demonstrated in many studies. However, it is difficult to retain the sodium HA as a physiological barrier at the traumatized surfaces in the joint cavity for periods of up to a few weeks during adhesion formation. Recently, hyaluronic acid-carboxylmethylcellulose (HA-CMC) combined into a resorbable membrane has been used in the fields of gynecological surgery or abdominal surgery and a reduction in adhesion formation has been shown in some clinical studies in those fields. HA-CMC is a non-toxic, non-immunogenic and biocompatible hydropholic gel, but it contains carbodiimide as a chemical regent and is thus not the same as naturally occurring HA. Now, a new product, HA gel sheet, has been developed, which is obtained from HA solution and which is composed of HA alone. The aim of this study is to examine the effectiveness of these materials in preventing adhesion in vivo. For this purpose, the biomechanical and histological characterizations of adhesion were evaluated in a rabbit knee model.
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宮崎 浩, 鍋島 由希, 林 紘三郎
原稿種別: 本文
p.
71-72
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
Tensile properties of vascular endothelial cells (ECs) obtained from the rat common carotid artery and external jugular vein were determined. Each cell floated in Hanks' balanced salt solution of 37℃ was gripped with a pair of micropipettes and, then, stretched at the rate of 6μm/sec by moving one of the micropipettes with a linear actuator. The cells harvested from both artery and vein were broken at the load of approximately 0.2μN; their elongation to failure were 18 and 14μm, respectively. These maximum load and elongation to failure were much smaller than those of fibroblasts [Ref. 3] and vascular smooth muscle cells [Ref. 4]. These results suggest that the cytoskeletal structures of ECs in the artery and vein are similar to each other and stress fibers in both cells are thinner than those in fibroblasts and smooth muscle cells.
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山野井 一郎, 玉川 雅章, 松尾 純明
原稿種別: 本文
p.
73-74
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
This paper describes the fundamental research to apply penetration of micro-jet to disintegrate microcapsules in Drug Delivery System (DDS). Deformation processes for a bubble near round elastic body by shock wave were observed. It is found that wall curvatures and the position of a bubble effect bubble oscillation period and maximum bubble volumes, and high kinematic viscosity of surrounded liquid prevent oscillating bubble from collapse.
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羽鳥 敦司, 河合 伸也, 桜本 逸男, 田口 敏彦, 花崎 陽介, 河野 俊一
原稿種別: 本文
p.
75-76
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
This paper describes a study on the mechanical properties of ligament of a rabbit. To investigate a biomechanical feature of spine, it is need to measure the mechanical properties of component parts of spine such as ligament, and the properties are used for the numerical simulation. But it is difficult to measure properties of component parts of spine accurately because of its minuteness and low rigidity, and change of the properties as time pass. In this study, we showed the effect of the strain rate on the mechanical properties of apical ligament by the tensile tests using specimens of white rabbits' cadaveric spines. Furthermore, we computed parameters for the numerical simulation from this data.
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朝長 裕樹, 出口 大悟, 廣川 俊二, 有吉 省吾
原稿種別: 本文
p.
77-78
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
Accurate kinematic information of the knee joint is essential for an exact diagnosis of patient with artificial knee and for its design. In this paper, we gave an outline of advanced technique for estimating three-dimensional knee motions using single plane projections of an artificial knee joint. Our estimation scheme was based on Banks's work, but further significant improvements were made. Computer modeling studies indicated that our technique could achieve sufficient accuracy for a clinical use. It was proposed that this technique could provide a simple and practical way for evaluating the current total knee designs and for developing improved knee replacement devices.
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植木 貴司, 廣川 俊二, 大月 伸男
原稿種別: 本文
p.
79-80
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
In our previous study, parameterized polynomial function was applied for describing the artificial knee joint surfaces and the results were found to be superior to the established practices. However, this polynomial function was difficult for reconstructing human knee joint surface with minute undulation. To overcome this problem, we tried an additional application of Fourier series approximation in this study. First, the global shape of objective surface was described by polynomial function. Then, minute undulation was approximated with Fourier series. Finally, two sets of approximation were combined. This surface fitting method was applied to swain knee joint surface and curvature analysis was performed.
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松村 仁, 山田 宏
原稿種別: 本文
p.
81-82
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
We carried out finite element analyses for an endothelial cell which is subjected to three-types of stretch through a substrate. The cell, the nucleus and the substrate are modeled as a neo-Hookean material with different material constants. The result from stress/strain analyses show that the strain decreases with the height which agrees with the experimental result in the literature, indicating that the transmission of the deformation from the substrate to the cell has some reduction even in the case of an elastic material. The result also shows that the nucleus causes a high level of stress in the cell under the nucleus. The result also provides the three-dimensional orientation of stress fibers between the apical membrane and the basal membrane on the basis of a proposed hypothesis.
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中尾 健太, 大場 謙吉, 田地川 勉
原稿種別: 本文
p.
83-84
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
An aortic stenosis is a disease that an aortic valve can not open completely at a cardiac contraction phase. An aortic regurgitation is a disease that the aortic valve closes inadequately. In the aortic stenosis, flow passing through the aortic valve becomes a jet like one. In the aortic regurgitation, a reverse flow appears. It is thought that the blood flow into coronary arteries is influenced by the aortic stenosis and /or the aortic regurgitation, since the inlet of coronary arteries exist in the aortic base. Then, in this study, in order to investigate the above-mentioned influence, a realistic model of an aortic valve was manufactured. For manufacture of the model valve, a casting method using a 3-dimensional modeling machine was adopted.
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堂園 明寛, 板東 潔, 大場 謙吉
原稿種別: 本文
p.
85-86
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
It is known that some blood vessel diseases such as arteriosclerosis, aneurysm and so on, are generated locally at a curved part and a branched part of a blood vessel which is deformed in a complicated manner. At these parts, complicated flow phenomena such as reverse flow, flow separation and vortex take place. It is thought that these phenomena are generated by an interaction between the blood flow and the blood vessel. In order to investigate this interaction, collapsible tube was used as in vitro model of the vein and or coronary artery. We made a calculation of the steady flow in highly deformed and buckled collapsible tube by using a finite element method. We compared our calculation results with the experimental one. As a result, both resulta agreed with another.
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岩瀬 英仁, 劉 浩, 藤本 眞一, 姫野 龍太郎, 早坂 智明
原稿種別: 本文
p.
87-88
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
An efficient, image-based, computational modeling method for computational fluid dynamic study of left ventricle (LV) haemodynamics is presented. A Two-Chamber-View modeling method is proposed for reconstructing an anatomically realistic model of left ventricle, which is based on ultrasonographic images of two mutually perpendicular slice sections align with the long-axis. Each cross section of the short-axis is approximated as an ellipse with two radii determined from the extracted endocardial borderline, and is stacked up from the apex to the mitral- and aortic-valve planes to generate a fully three-dimensional geometric LV model. the computed results indicate that realistic modeling of both geometry and physiological conditions of left ventricle is of great importance in correctly predicting the behavior of the strong vortex flow patterns and their influence on the heart function.
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古川 一憲, 古巣 克也, 三木 一生
原稿種別: 本文
p.
89-90
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
In this paper, Finite Element Method (FEM) skeletal model of 6-year-old child was developed to analyze child movement and injury. Because there are few three dimensional child skeletal data, adult FEM model was scaled down to child size, pelvis model was newly created from X-ray CT images obtained from the scan of 6-year-old child pelvis bones and the thoracic part was mechanically expanded for size adjustment. As verification, the size discrepancy between child FEM model and human 6-year-old child was less than about 10%, the calculated movable range of hip joint was close to measured one and calculated bending strength by FEM model was nearly equal to measured bending strength by experiment.
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仲町 英治, 三木 一生, 大森 潔, 奥山 敏郎, 武川 雄一
原稿種別: 本文
p.
91-92
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
The translational acceleration concussions damages, such like the cerebral coup and contre-coup side damages, are reported in a traffic accident and crash contacts of human bodies in sports activities. The comparisons with the conventional HIC criterion and experiments by developed FE evaluation technique of Finite element evaluation algorithms are newly developed based on Gross's cavitation theory. It shows 100kPa for a damage criterion. In this paper the hydrostatic pressure criterion was verified through FE analyses propagation at the time of the head collision based on cavitation theory of Gross et al. The verification experiment by FEM analysis and the artificial head model are conducted, In experiments, PVC skull and gelatin brain are used to model the human head.
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今戸 啓二, 三浦 篤義, 池内 秀隆, 大西 謙吾, 永利 益嗣, 宮川 浩臣
原稿種別: 本文
p.
93-94
発行日: 2002/09/20
公開日: 2017/08/01
会議録・要旨集
認証あり
A new unweighting vest for gait training machine is developed. For gait training, the load on the trainee's lower limbs has to be reduced to safe and manageable level. In conventional parallel-bar training, upper limbs are used for this purpose. However, only the trainees with enough muscle strength can perform this method. To overcome this disadvantage, performing the training with an unweighting vest is desirable. However, gears on the market are not durable. This paper repots on a method and its experimental results on the modification of the vest. The uncomfortable pressure on the trainee's body is considerably reduced by installing an ischium-supporting rod in the sling-type vest.
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