A hybrid system composed of solid oxide fuel cell (SOFC) and gas turbine (GT) is expected to achieve very high efficiency over 60-70% LHV. However, in order to operate the system at high efficiency and high power density which leads to cost reduction, it is important to manage the whole SOFC temperature as uniform as possible. Cathode air recirculation is one of the simplest approaches to improve the temperature distribution of the cell. In the present study, numerical simulation of the air recirculation hybrid system was carried out. All the system components are modeled, and the effects of recirculation ratio on the total system performance are evaluated. Furthermore, comparison betweenn the ejector system and the blower system, evaluation of partial load performance are investigated.

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A new method for air cooling of solid oxide fuel cells was proposed and was analyzed numerically. In the present method, air is divided and then is supplied to the cathode of cell. The distribution of temperature and the thermal stress in the cell were discussed by comparing the present method with conventional method. By the present method, the distribution of temperature of the cell became more homogeneous than that of the conventional method. Therefore, the thermal stress in the cell decreased below the half of that of the conventional method.

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In a polymer electrolyte fuel cell, consumption rates of hydrogen gas and oxygen gas and a production rate of H_2O due to an electrochemical reaction were determined from the data of a current distribution in a MEA measured by a magnetic sensor. The amounts of the electro-osmotic dragging water with proton transport and the diffusion water from the cathode to the anode were also calculated with the experimental equations in the other's studies. Based on these values, the relative humidity of the fuel gas in the fuel cell was calculated. It was found that the relative humidity decreased after beginning of power generation. This calculated relative humidity was also close to the value measured by the laser interferometry.

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Thermal efficiency of polymer electrolyte fuel cell extremely depends on a water distribution in Gas Diffusion Layer (GDL). Fuel cell model was prepared in order to investigate the water distribution in GDL by ultrasonic techniques. Acoustic impedance of GLD, which is porous plate of carbon, was estimated as bulk model to know approximated value of reflection ratio of ultrasonic echo. We attempted to measure an instantaneous ultrasonic echo that changes by the quantity of the water to detect existing water in GDL.

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A gas-liquid two-phase flow in a curved micro-channel is encountered in many applications, such as a separator fot polymer electrolyte fuel cells. However, sufficient information on fundamental parameters in two-phase flow in a curved micro channel, such as flow pattern and pressure drop are not available in designing such devices. In the present investigation, detailed observations on the flow patterns and measurements for pressure drop characteristics affect by curvature effect in a capillary tube were carried out. The hydraulic diameter of the serpentine capillary tube was 2.0mm, and the radii of curvature were 1.0mm and 3.0mm. The flow pattern and pressure drop are characterized by the surface tension between the gas and liquid phases and also by the surface wettability of the tube wall.

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Spectral transmission characteristics of piling quartz filters with double-layer anti-reflection (AR) coat were investigated for diffuse irradiation through Ray Tracing numerical simulation. It was revealed that the piled quartz filters was very useful for the thermophotovoltaic (TPV) electric power generation system when the number of the filters was enough large. Furthermore, then, the total efficiency of the TPV generation system can be expected to be about 20% using the piled quartz filters.

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To understood the effect of Palm Oil mixing on spray combustion characteristics of diesel oil, the intermittent spray flame formed in a high temperature and high pressure combustion vessel was visualized by ICCD camera and analyzed by two color method. The mixing rate of Palm oil to diesel oil was changed up to 60%. It was confirmed that the ignition delay was slightly shortened by Palm oil mixing. The flame temperature becomes slightly lower and the amount of soot production decreased slightly with the Palm oil mixing, however, the difference is not so large.

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It is difficult to use Palm oil Methyl Ester (PME) in winter and cold districts because it has high pour point. PME solidifies at less than 100MPa when it is pressurized at room temperature. To improve low temperature fluidity of PME, JIS No.2 diesel fuel, ethanol and dimethyl ether were blended into PME, and the influence of their blend ratio on solidification pressure was examined. The solidification pressure was determined by measuring the laser transmission through the blended fuels in visualized pressure vessel. As the result, diesel fuel and ethanol blend into PME made the solidification pressure at room temperature increase to 150MPa or more.

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In order to use Coconut Oil Ethyl Ester (CEE) as an alternative diesel fuel, the diesel combustion of CEE is investigated using a small DI diesel engine, and is compared with that of Coconut Oil Methyl Ester (CME) and JIS No.2 gas oil. As a result, the pour point of CEE (-7.5℃) is lower than that of CME. CEE and CME have lower exhaust emissions compared with gas oil. Especially, at 100% load CME and CEE reduce smoke emissions by about 45% compared with gas oil. The thermal efficiency and exhaust emissions of CEE are almost the same as that of CME. From the experimental results, CEE can be used as an alternative petroleum diesel fuel.

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Although it is reported that a particulate is reduced when an oxygenated fuels mixed to diesel engine fuel, the detailed reduction mechanism has not been solved. By this research, three kinds of almost equal oxygenated fuels of an oxygen content rate are mixed to the fuel which a particulate formation mechanism and the characteristic with the reaction fluid tube, and the result of having investigated the inhibition mechanism and the characteristic by each oxygenated fuels is reported.

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This study demonstrates the experimental investigation into the effects of EGR and fuel injection condition on engine performances and exhaust emissions from CR-DI diesel engine fuelled by biodiesel. Obtained results show that NO_x emission from biodiesel can be reduced effectively by increase in EGR rate. Then, smaller increase in smoke, CO or ISF emission can be observed in the case of biodiesel fuel compared to ordinary diesel fuel. Also, high-pressure injection is effective to reduce SOF content in PM from biodiesel under the EGR condition.

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In the previous report, the authors have explained the difference of combustion characteristics and diesel emissions between rapeseed oil methyl ester (RME) and diesel fuel in high boost charged system and high pressure common-rail injection system. In this study the mass of exhaust particulate matter (PM) of RME was measured quantitatively before and after oxidation catalyst at 1200rpm, EGR rate 30% and full load in single cylinder engine. The soluble organic fraction (SOF) in PM was analyzed in order to separate fuel and lubricating oil by gas chromatograph.

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Application of biodiesel fuel (BDF) to diesel engine is very effective to reduce CO_2 emission, because BDF is carbon neutral in principle. However, it is possible that the exhaust emission characteristics of diesel engine fuelled with biodiesel is not good. In fact, it has been frequently reported that biodiesels yield an increase in NO_x emission in many diesel engines. Therefore, some aftertreatment systems are needed for meeting the future emission regulations using biodiesel. In this study, rapeseed methyl ester (RME) was applied to diesel engine equipped with NO_x storage reduction catalyst (NSR) and diesel particulate filter (DPF). The NO_x reduction rate of NSR was drastically decreased by using RME, even if injection quantity of RME for rich spike was enhanced. This rich spike injection using RME also caused an increase in PM emission.

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In this study, it is focused on spray characteristics of Dimethyl ether (DME) injected into low temperature or pressure ambient. Quiescent ambient made in a constant volume chamber, and shadowgraph method or laser scattered method was conducted to visualize a shape of DME spray or liquid phase DME. Penetration of DME spray and liquid phase were measured with acquired images of DME spray and scattered lights. The results obtained in this experiment describe below. As injected DME sprays in a low pressure ambient, flash boiling phenomena occurs. As an ambient density increases, dispersion angle of DME spray with flash boiling decreases. As DME spray develops without flash boiling, the spray dispersion angle increases with the increases in the ambient density.

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In this study, it is focused on spray characteristics of Dimethyl ether (DME) injected into high temperature or pressure ambient. Quiescent ambient was made in a constant-volume chamber, and shadowgraph method or laser scattering method was conducted to visualize a shape of DME spray or liquid-phase DME. Penetration distances of DME spray and liquid-phase DME were measured with acquired images of DME sprays and scattered lights. The results obtained in this study were described below. As DME is injected in a low pressure ambient, flash boiling occurs and liquid lengths of DME spray are shortened. And because DME is a high volatility fuel, liquid length of DME spray is significantly short in high temperature ambient, and gas-phase DME occupies the spray.

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Numerical calculations of Dimethyl ether (DME) spray using KIVA code were examined. To prepare proper physical-chemical properties of DME, experimental equations were made and the estimation methods were examined. The calculated results were evaluated by comparing them to experimental results. At high temperature region above the critical temperature, the calculated DME sprays agreed with the experimental ones. As the ambient temperature decreased, however, the error increased. It was suggested that breakup model and evaporation model should be improved. It was also found that smaller mesh size compared to that suitable for diesel fuel was needed.

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Recently many issues related to automotive engineering, such as the environment and energy problems have gained attention. These social-related issues are giving impetus to the adoption of urgent measures such as alternative fuels and new combustion techniques for the internal combustion engines. In this context, dimethyl ether is thought to be a potential alternative to diesel fuel, as it has lower overall pollutant emissions and better economy. On the other hand, oxygen-enriched combustion has been gaming acceptance as an environmental friendly combustion, because this can reduce soot and NO_x emission. The purposes of this paper are to examine the extinction properties of DME flames and the feasibility concerning the application oxygen-enriched combustion to DME flames using a counterflow burner. Firstly, the strain rate at extinction is measured for dimethyl ether and propane flames as a function of flame temperature under the same flame structure. Secondly, the strain rate at extinction is also measured under the condition that the flame structures are changed, but the adiabatic flame temperatures are not varied. In addition, numerical calculations are also performed using detailed chemical-kinetic mechanism to obtain value for extinction and compared with measurements.

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Nutuna Island Indonesia has one of the largest deposits of natural gas in the world. However, the Nutuna gas contains a large fraction of carbon dioxide of around 70%. Previous research has shown a combustion promotion effect by adding hydrogen to the gas in a spark-ignition internal combustion engine. The hydrogen addition by 20% in volume was sufficient for improving thermal efficiency and power output at stoichiometric mixture condition. This paper experimentally analyzes fundamental characteristics of the Nutuna gas reforming to produce hydrogen at different initial temperatures. Effects of oxygen and steam on dry reforming of the gas are also discussed.

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In this study, an optically accessed combustion vessel and high speed imaging were adopted to obtain laminar velocity measurements of spherically propagating hydrogen-air explosions at 0.06, 0.10, 0.175, 0.25 and 0.50MPa. Equivalence ratios of 0.4, 0.6, 0.8 and 1.0 were investigated and the influence of flame instability is discussed in terms of the Markstein number and flame instability burning velocity ratio (ratio of the laminar burning velocity at a flame radius of 60mm to the unstretched laminar burning velocity). The unstretched laminar burning velocity was approximately constant between 0.06 and 0.175MPa at any given equivalence ratio. However, the unstable laminar burning velocity and the flame instability burning velocity ratio increased with pressure. Markstein numbers decreased with increasing pressure. A liner relationship was observed, between Markstein number and flame instability burning velocity ratio.

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In this study, authors aim to convert heavy fuel or solid fuel into lighter liquid fuel with high quality and, authors propose fuel reformulation through sonochemistry and fuel design approach. Concept of Fuel design approach is to control fuel properties by mixing fuel. Its origin is Chemical-Thermodynamics and, heavy fuel converts into lighter fuel by it. The origin of sonochemistry is acoustic cavitation: creation, growth, implosive collapse of gas bubble by irradiation of high intensity ultrasonic. The sonochemical effect on organic liquid causes cleavage of C-C bond by hot spot conditions (more than 5000[K] and 100[MPa]) that are generated in collapse. In this paper, sonochemical reaction of mixing fuel was analyzed for ultrasonic of 20[kHz] and its result shows interaction of each components by fuel design approach with sonochemistry approach.

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We simulated methane hydrate dissociation in a water-rich sand layer by 3D CFD method with unstructured grid systems. We modeled the sand layer as a calculation domain of face-centered cubic lattice. In this sand layer, we suppose 3 cases of computational conditions. The First case is liquid single-phase condition, the second is bubble-existing two-phase condition, and the last is bubble-generation condition. By this simulation, we got penetration and dissociation rates, and compared them to existing experimental data. Finally we conclude that the present method can simulate actual dissociation phenomenon well.

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A basic characteristic of parallel flow with a chemical reaction, especially the effects of chemical reaction on the process of mixing has been investigated. In this study, the process of the mixing was experimentally examined using the LIF-PIV method. In this paper, the reaction between the ammonia solution and the acetic acid one has been selected as a simple irreversible chemical reaction. The reaction between these solutions has negligible small heat of the reaction. The process of mixing was visualized by the LIF method. In order to evaluate the process of mixing quantitatively, the PIV method has been carried out. Distributions of mean velocity vector and kinetic energy were examined by this method. As a result, it is found that the mixing with chemical reaction is relatively suppressed, comparing with that without chemical one.

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The aim of the present study is to investigate convection heat transfer and fluid flow in an insulated cavity, i.e., indoor with the injection and suction ducts. Emphasis is placed on the effect of the partition plate in the cavity on the thermal and velocity fields and local area heating-performance. The numerical method is based on the incompressible Navier-Stokes equations. The fluid in the cavity in the absence of the vertical partition plate shows the large clockwise flow pattern and as time progresses, the cavity temperature is gradually increased and becomes uniformly over the whole region of the cavity. When the vertical plate is installed at the central location of the upper horizontal wall, the higher velocity field appears in the left area of the indoor and the corresponding fluid temperature is higher than that of the right area. By installing the partition plate, the temperature distribution in the indoor is controlled. In other words, only the desired space of the cavity is warmed, because the flow pattern is changed due to the presence of the plate.

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When a heat transfer tube fails in a steam generator of liquid sodium cooled fast reactor, highly pressurized water or steam inside the tube blows down into liquid sodium that exists in the shell side and thus the sodium-water reaction will occur. The reacting zone, in which high temperature appears and corrosive sodium compound such as sodium hydroxide (NaOH) exists, will affect a structural integrity of neighboring heat transfer tubes and shell structure. Hence, an investigation of the reacting zone in the sodium-water reaction phenomena is of great importance for safety evaluation in the steam generator. A numerical method of multi-dimensional and multi-phase thermal hydraulics coupled with the sodium-water reaction has been developed for this purpose. In the present paper. the influence of the initial pressure in the shell side on the reacting zone has been investigated numerically, as well as the geometric configuration of pin-bundles.

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The present study deals with unsteady laminar fluid transport phenomena around a pair of diamond-shaped cylinders placed side by side or in a line in free stream. The Navier-Stokes equations are discretized using finite difference methods to determine the time history of velocity vector distribution in the flow field. Emphasis is placed on the effects of the Reynolds number, Re, and the ratio of cylinder separation distance to length of diamond-shaped cylinder, s/d, on the flow patterns. The study discloses that (i) the generation of von Karman vortex streets behind the diamond-shaped cylinders are intensified with an increase in the Reynolds number, (ii) the flow pattern in the wake region of the diamond-shaped islands is affected by s/d, and (iii) the corresponding flow map is obtained in the form of the Reynolds number versus s/d.

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In the authors' previous report, the numerical results on natural convection from a downward-facing isothermal plate were compared with the experiments by Aihara et al. The numerical analysis using a CFD code showed a good agreement with the actual flow and thermal fields obtained in the experiments. However, the analysis was limited to the fluid flow and heat transfer from a downward-facing surface of the isothermal plate as no information has given on the flow and thermal fields from the upward-facing and lateral surfaces of the plate in the Aihara et al.'s experiment. In this report, the flow and thermal fields on the entire surfaces of the horizontal isothermal thin plate are numerically simulated using the same CFD code and the numerical results are presented.

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The aim of this study is to clarify the statistical properties of a plane jet diffusion field in liquid. The velocity and dye concentration have been measured by the LDV and the light absorption method. It was found that the downstream variation of square of reciprocal mean velocity on the jet axis and the half width of the jet vary linearly with downstream direction. It is ascertained that statistical properties of the present plane jet show good agreements with past other researcher's data.

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This research was aimed to clarify the cause of the performance deterioration that occurred in a continuous operation of the banded-structure membrane fuel cell module, which consisted of 15 polymer electrolyte membrane fuel cells laid out in a plane. Therefore, the voltage of each cell, the concentration of oxygen in the cathode vicinity, cell temperature and AC impedances were measured. As a result, the cause of the performance deterioration generated the condensation by humidity's locally increasing in the cathode vicinity, obstructed the gas exchange, and concluded that the possibility by so-called flooding was high.

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A rich-lean flame burner is widely used for supplying domestic hot water and heating in Japan. This burner has low NO_x and CO emissions, and conventionally consists of a layered structure of lean flame with both sides of rich flame. A new concept burner with air supplied from boundary zone between rich and lean premixed nozzles, produces lower NO_x and CO emissions, although the characteristics of the new burner are clarified only in experiment. In this study, a two-dimensional numerical simulation of the new burner is executed to clarify the mechanism of the lower NO_x and CO emissions compared to conventional burner.

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The thermocapillary flow in a low-Prandtl-number half-zones is investigated numerically in the case that the free surface is partially confined by thin solid walls. The linear stabilities to three-dimensional disturbances and their physical destabilizing mechanisms are addressed, with variations of the aspect ratio of the liquid bridge, the axial position of the free surface, and the ratio ξ of the free surface length to the full liquid height are considered. With decreasing ξ it is found that the contribution of the elliptic mechanism on the instability fades away and that the relative importance of the centrifugal mechanism consequently increases. The balance change of those mechanism leads to four different instability modes, including two oscillatory modes. For a sufficiently small ξ the instability appears to be purely centrifugal.

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Two-dimensional numerical simulations have been carried out in order to investigate wave dynamics and kinetic and surface energies of wavy falling liquid films. Governing equations, which are continuity equation, Navier-Stokes equation, and equations of interfacial boundary conditions including surface movement and effect of surface tension, have been solved directly by means of a numerical scheme based on the finite difference method. In most cases, periodic disturbances superimposed at inflow boundary grow to developed waves which retain the given periodic behavior. In some cases, however, random wave appear after the developed waves. Variations of kinetic and surface energies of the periodically developed waves and the random waves have been discussed.

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In recent years, high promotion of efficiency and reduction of harmful emission such as NO_x become a big problem in practical combustor such as gas turbine combustor and a boiler furnace consideration to an environmental problem. This research uses flamelet approach for combustion reaction, and calculates till a field develops. Then, we convert it into elementary reaction calculation and predict NO generation.

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This paper describes the use of model order reduction method (MOR) for a fast dynamic structure analysis. Recently, MOR based on the Kryrov-subspace method has been reported the efficiency for the large scale problems in various dynamic system. One of us is designing a micro- gas turbine engine. In this paper, we use MOR for the effective design of small rotor in the micro- engine. Numerical example demonstrates the accuracy and efficiency of MOR.

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The finite element method is applied to the thermal buckling analysis of laminated composite shells of revolution under axisymmetric temperature field. The displacement field within each element is represented by Fourier circumferential components. The effects of axisymmetric initial imperfection on the buckling temperature are investigated.

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To analyze the performance of the heat exchanger (HEX) in air-conditioners within a realistic time frame, we propose a simple modeling technology that uses a reduced mesh. The pressure loss of the HEX is given by the momentum source term, and the heat-transfer performance of the HEX is approximated by using a wall function as the boundary condition. We clarified the acceptable value of required velocity distribution and the amount of winds, when setting up a temperature boundary condition for the purpose of improvement in the speed of an air-conditioner mounting design supportive tool. As a result, computation time was shortened to 1/3.

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Intermediate parameters are proposed in this paper to represent the dynamic characteristics of airbag deployment. These intermediate parameters are calculated directly from an airbag deployment simulation by the Finite Pointset Method (FPM). The intermediate parameters are also employed to examine the feasible domain of injury indexes, so that the effects of airbag parameters on injury indexes can be predicted. Four airbag parameters were tested based on an L9 orthogonal experiment performed with FPM. The effects of these parameters on injury indexes are discussed. This procedure facilitates evaluations of the effects of airbag parameters on injury indexes in the early stage of designing restraint systems.

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Statistical model of the domestic portable PC market was developed as a regression model by neural network using structural equation modeling and Monte Carlo simulation. Specification, sensory items like design and usability, street price, and the unit sales were used as parameters of the statistical model. Specification of PCs was obtained from brochures. Sensory items were collected from magazine reports and reviews on WEB sites. The brand and the effect of advertisement were disregarded. With this modeling method, contribution of price, specification and sensory items can be compared simultaneously, and product specification difference can be described as price.

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This paper has examined opening characteristics of an aluminum bottle experimentally. When a cap of bottle is rotated and opened by the fingers and palm, it is found the opening torque of cap shows two peaks during the opening process of cap ; the 1st peak of torque occurs when the cap initiates the rotation by overcoming the frictional resistance of screw, and the second peak of torque appears when the first bridge initiates the fracture. It has also been clear that the internal pressure influences the 1st torque much and the friction of skirt parts contributes about 20N\cm to the 1st peak. To improve the opening characteristics of cap for the aluminum bottle, it is turned out that the reduction of the 1st and 2nd torque of screw opening process is effective.

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Compliant mechanisms are a relatively new type of mechanism that intentionally uses structural flexibility to achieve specified motions. An environmental uncertainty must be considered during compliant mechanism design if the device will be deployed at a sub-millimeter scale, such as with MEMS (Micro Electro Mechanical Systems). As the design scale becomes smaller, the influence of environmental uncertainties increases. In this research, a new topology optimization method is constructed for the design of compliant mechanisms that aims to minimize uncertainties of applied tractions, in order to improve robustness. Several numerical examples are presented in order to confirm the usefulness of the proposed method.

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In this paper, methods to evaluate optimality of a cooling pipe system in plastic injection moldings is presented. When plastic products are molded, residual stresses that cause warps and cracks in some years after molding are generated by a non-uniformity of temperature cooling rate in the die. The shape and layout design of cooling pipe system is the most effective factor for the improvement of distributions of coolant flow and temperature in the die. In this study, an optimum cooling pipe layout to give a uniform temperature distribution in the die is proposed to reduce the residual stresses. Then an optimization method is applied to design an optimal cooling pipe system, where the objective function consists of the plastic material temperature in the die calculated by a numerical simulation.

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Over-fitting of noisy teacher data is a serious problem for artificial neural networks (NNs). Their learning method based on Bayesian inference was proposed by MacKay in order to prevent over-fitting and generate a smooth response surface (RS). Using this method, the response surface of neural networks can be used to predict optimal input conditions, because it has good generalization (interpolation) ability. We specified and verified the learning algorithm and the modification method of hyper parameters, which are coefficients that appear in an objective function with penalty terms. After three different modification methods were applied to interpolation examples, we chose the superior modification method. Finally, the response surface of neural networks using the superior method was applied to an optimization problem in which the fiber orientations of a laminated composite structure were determined so as to minimize the difference in two displacements. We concluded that the learning algorithm and the modification method are effective to optimization problem.

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To secure vehicle safety performance in frontal crash is one of the most important factors in vehicle design. In late years occupant safety in frontal crash is getting better as vehicle crash characteristics such as cabin deformation and vehicle deceleration are improved. However, body mass is increasing at the same time due to necessary body reinforcement in order to improve the vehicle crash characteristics. This paper describes the practical multipurpose design optimization method using a simplified spring-mass frontal crash model to achieve the better vehicle crash characteristics with smaller body mass. The result of this study may be useful to establish the more rational decision-making process in vehicle design.

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A new optimization method aimed at searching a global optimum solution and decreasing the number of iterations is described. The feature of the new method is creating an orthogonal array and changing the level value of design factors every search step. The performance of the method was observed on the optimization problem of mechanical design which involves discrete and continuous variables. The newly developed method is found to be very effective for searching the global optimum solution of the mechanical design problem.

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The multi-objective design exploration of the two-dimensional shielding effect for engine noise using V-tale wing has been performed. Two objective functions are considered as the minimization of the sound pressure level at the side and bottom locations relative to the fuselage, which values are evaluated by using the linearized Euler equation. Two design variables are defined as the wing length and the wing cant angle to set on the fuselage. The response surface method based on the kriging model is employed as the optimizer to reduce the time required for design exploration. As a result, there is no tradeoff between two objective functions, i.e., the sound pressure level at the side and bottom measuring locations can be reduced, simultaneously. The wing cant angle which is set at roughly 65 deg is most effective to shield the noise. It is justly the necessary condition to reduce the sound pressure level that the wing length becomes long. Moreover, a self-organizing map as a data mining technique reveals the knowledge in the design space regarding the correlation among the objective functions and the design variables.

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Large wind tuebine blade is prospected to be CF/GF hybrid blade made with Carbon Fiber Reinforsced Plastic and Glass Fiber Reinforced Plastic, and structural optimization of the blade is multi-objective optimization problem (MOOP) about weight and cost. The optimum solutions for MOOP are Pareto optimum solutions. In this paper, the MOOP is solved using Multi-Objectibe Genetic Algorithm (MOGA). Meanwhile, blade structure is necessary to satisfy a constraint not to fracture under maximum load. To evaluate the constraint, FEM analysis is used. This cause enormous calculation cost. In this paper, to reduce this, response surface approximating the degree of constraint satisfaction is created. Since Pareto solutions obtained using response surface don't necessarily satisfy the constraint, it should be confirmed whether they satisfy the constraint or not using FEM analysis. If some of the solutions don't satisfy the constraint, whose response data is added in, and the response surface is restructured to improve its accuracy. Repeating restructuring, obtained Pareto solutions will converge to exact Pareto Optima. At this point, in the MOGA Optimization, the accuracy of convergence of solutions is improved using quasi-Pareto Optimum Initial Population to reduce the number of restructuring. As a result, the the number of FEM analysis is reduced to 1400 times.

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In current FE modeling, it is difficult to make them connect the models separately made to one because the size and the shape of the mesh that composes the model are different, and the node coordinates of each model are not corresponding by the bonded surface. Then, it was possible to connect it as one of FE models by taking the FE models on a virtual space, changing the mesh shape of another model based on one of models, and matching coordinates of the node on the bonded surface. In addition, the system was made to integrate clusters, and the improvement of the processing time to match coordinates of the node was examined by working with two or more computers.

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At present, very small gear and electrostatic motor are fabricated on silicon substrate using semiconductor micro processing technology, and it becomes necessity to process of these micro components. But, handling technology that can handle micro elements, as small as several to several ten micrometers, has not been developed yet. To solve this problem, we specially process diamond material and design end effector that handle micro elements. At manufactured micro 3 axis stage by way of trial that can identify the location of stage by submicron resolution and put in chamber of SEM. We add a CCD camera as an observation system for assistance in SEM

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Though some electrostatic microactuators are proposed as a source of drive of the micro electro mechanical systems so far, the ability that the electrostatic force/energy has can't be drawn fully, and only the little power can be taken out in the outside. In this research, the novel drive principle of the microactuator in which electrostatic energy can be taken out in the outside as a mechanical work efficiently by making electrostatic energy collaborate with the elastic energy was devised. It was named Energy Conversion-type Micro Actuator powered by Collaboration of Electrostatic and Elastic energies/forces, EC-Macbee. In order to realize the actuator utilizing this drive principle, necessary mechanism was devised, and the shape and dimension of the non-linear spring of the actuator was designed by FEM analysis.

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