This paper presents an approach for mesh simplification of CAD mesh models based on hierarchical face clustering (HFC) by fitting primitives. We first improve a primitive fitting strategy which results in robust and higher quality primitive clusters comparing to conventional methods. We also present primitive fitting methods for cones and tori. Our method resolves some issues occurring in conventional HFC-based primitive fitting methods. We applied this result to mesh simplification for DMU based on constrained QEM mesh simplification method.

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This paper describes improvements of Gmsh Tool that is a simple GUI tool and makes Gmsh's modeler and mesher easy to operate. The features of the new version of Gmsh Tool are: unlimited Undo/Redo capability has been newly implemented, the structured meshing has been simplified and the linkage between Gmsh Tool and the Adventure TetMesh has been enhanced.

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The manufacturing industries have already used 3D CAD System. There are some examples that 3D shape data is not utilized effectively on product development process. These problems occur by two issues. First, 3D shape data is created inefficiently. Second, product development process that utilizes 3D shape data effectively is not constructed. We realized that product shape keeps materializing by progress on product development, and developed the E-Methodology. By applying the E-Methodology, 3D shape data is created effectively and is utilized effectively on the product development process. And it effects that development period is shorter and product quality is higher. This paper explains the E-Methodology.

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Emerging synthesis and reusing system of experts engineering design process knowledge has been developed. The implemented knowledge based system provides experts work procedures with flow chart and relating information such as constraints and conditions or engineering rationale. The system enables junior engineers to follow the best-in-class work done by veterans. The results have shown a substantial effect on design skill transfer support.

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Products involve some risks when they are delivered to the markets. If such product risks can be identified before product deliveries, companies may have chances to minimize the impacts by preparing for contingencies such as product failures. Currently, methodologies such as Failure Mode Effect Analysis and Probability Risk Assessment are used to control and reduce risks during product development. However, because of the methodologies require a lot of human hours to apply, practitioners assess product risks in predetermined elements of a product, but entire product elements. This paper proposes a novel methodology to identify product risks by a comprehensive assessment of product elements.

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Recently, development risks have been major problems in content development, due to difficulty in acquiring customers' uncertain demand. This paper proposes a new project management methodology, which enables content directors and developers to design a high level developing process on their own, based on customer reviews. In this paper, system development mainly progress by configuring review types and attributes. The support environment will suggest scheduling of tasks, based on observing point of users and developers. We try to provide customers, trial and error designing method by calculating costs which occur from reviews automatically. Two critical issues of system implementation are addressed: (1) a content development model, which is able to reflect customer demand from user reviews, (2) a project management process, which is able to present design guide to reduce development risks by simulating reviews as major hazards.

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Since the driver of vehicles gets most of necessary information by sight, visibility is very important for safety driving. During the driving of vehicles, two kinds of vision should be considered: one is direct vision from the eye point of a driver and the other is indirect vision using the mirror glasses located inside and outside the vehicles. This research focused on the former, direct vision, for a medium size commercial vehicle as an example, using vision analysis of computer software. The assessment of viewable and non-viewable areas at an traffic intersection, at where many accidents often occurred, was carried out considering the arrangement of the front pillars. Finally a design improvement was proposed.

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A GUI system for a fluid flow analysis code, Front/Flow/Blue (FFB), has been developed. This is an integrated system of pre-post processing tools, the FFB and a user-friendly GUI. This paper describes capabilities of the GUI system, especially its intellectual aspects.

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Recently, an increasing number of planetariums are using digital technology. In a fully digital planetarium, the dome image is generated by computers and it is projected onto the dome screen using projection system. In such an environment the observers see the non-stereoscopic image without using 3D glasses, so they can not use binocular depth cues to perceive the depth of the displayed image. However, the observers can experience the high presence sensation in the dome environment by utilizing the perspective and the motion parallax effectively. In this paper, creation method of dome display contents using the layered image was developed, and the effectiveness of this method was evaluated using an immersive curved display.

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This paper proposes a rapid prototyping system using aerial drawing for a product design used in everyday life. In this system the user can make 3D handwriting in the air by using AR technique, where a product will be used, while reducing a positioning error and a feeling of separation between real space and virtual objects by implementing the lighting system which lights up rear and virtual objects and makes shadows simultaneously. As well as it, we implemented the direct manipulation interface for the input and output of modeling data and got a prospect to enable cooperation with the existing CAD and RP.

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We have already developed a prototype of arm wrestling robot system for the analysis and understanding of emotional change with force display. The prototype system consists of a 5-DOF force display system with 4 air cylinders and a force sensor, and a human-like head robot with stereo visual servo mechanism. The robot introduces a force display response model based on the impact absorption of human force display. In this paper, sensory evaluation demonstrates the effectiveness of the operation by using the robot with the model.

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Handshake is an embodied interaction with contact. In our previous research, a handshake approaching motion without a voice greeting was analyzed, and a motion model was proposed based on the analysis. However, humans usually shake hands in a voice greeting. Therefore, in this paper, we develop a handshake approaching motion model in a voice greeting. In this model, handshake approaching motion is generated from trajectory of human hand using the second order lag element and dead time element. The effectiveness of the model is demonstrated by sensory evaluations using a handshake robot system.

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InterActor is a CG-embodied interaction character driven by iRT which is the InterRobot Technology that enables communicative motions and actions based on only speech input for entrained interaction and communication. In this paper, an embodied entrainment character chat system "InterChat" is developed by introducing an enhanced iRT model that can create motions where the communicative motions and natural actions can be generated easily from both the typing rhythms and the meaning of the words of sending and receiving messages because the typing rhythms resemble the speech rhythms. The effectiveness of this system for chat communication support is demonstrated by a sensory evaluation experiment conducted in a chat communication. As a result, this system is expected to be the basis for a new type of interactive chat communication.

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Performances of several kW class SOFC systems are regulated by cell performances and by performances of thermal managements. Cell performances were estimated and the endurance tests were carried out. System performances were regulated by I-V relation of the cells; the heat losses and recirculated heat ratio was evaluated. Based on the results, the analysis method of SOFC system was developed and applied to the practical system.

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In this study, Structural optimization analysis of the transportation was conducted by finite element method and ground structure method. This palette was the one way type pallet to export automotive components. The one way type pallets the one dismantled on transporting only once in the locale. Therefore, it is the present conditions to have decided the specification while confirming the assumption experiment evaluation and the local trial situation with the actual thing. Then, structural analysis was performed using the commercial finite element method (Marc ver. 2005). And ultimately, the best structure that cost reduction is expected was examined by decreasing weight while at least keeping strength of the palette.

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In order to examine the process of the rational product design, the screw of extra super small-sized in-line screw type injection molding machine was designed. Optimum design value of the screw was calculated with the parameter design which uses simulation. As for ideal function of the screw, the signal factor is the screw rotary speed, and the output property is the extruder output, it defined that the extruder output is proportional to screw rotary speed. The experimental result, be able to simplify trial manufacture and test of performance, it found that it is possible to make the flow of the design where the feedback does not occur.

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The final goal of this research is to propose a cooling pipe system design method of an injection molding die to reduce residual stress of plastic products. The residual stress causes defects in dimension of plastic products. We have tried to establish how to analyze mold filling process, cooling process and residual stress occurrence in the molding process by numerical simulation. The proposed procedures to analyze the residual stress have been applied to some numerical examples, and some different cooling pipe systems of injection molding die are compared each other.

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This paper proposes a design methodology to decide layouts and shapes of cooling channels in a plastic injection molding die for reduction of residual stresses in plastic products. In a cooling process of plastic injection molding, non-uniform temperature distribution causes some molded defects in molded products such as warps and cracks. The most effective factor to affect the temperature distribution is cooling channels. In the proposed method, the design problem of cooling channels is formulated as shape optimization problem considering the residual stresses in a plastic product as an objective function. Then, the layout parameters of cooling channels are taken as the design variables and the residual stresses in a plastic product are minimized.

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This paper presents a numerical optimization method for optimal configuration design of shell structures. It is assumed that the shell surface is varied in the out-of-plane direction to optimize its configuration, and the thickness is constant. A solution to compliance minimization problem subject to a volume constraint is proposed to maximize the stiffness of shell structures. With this solution, the optimal configuration is obtained without any parameterization of the design variables. The problem is formulated as a non-parametric shape optimization problem. The shape gradient function is theoretically derived using the material derivative formulas, Lagrange multiplier method and the adjoint variable method. The traction method, which was proposed as a gradient method in Hilbert space, is applied to determine the smooth shell surface while minimizing the objective functional. In the design velocity analysis of the traction method, earth spring elements are added to shell surface to restrain a rigid-motion-like shape variation and to stabilize the convergence. The calculated results show the effectiveness of the proposed method for optimal configuration design of shell structures.

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Codes for nuclear power generation facilities (rules on fitness for service for nuclear power plants) has been developed by the JSME committee in 2004. However, JSME does not endorse any facility in accordance with this code. Users must understand interpret of this code and accept responsibility for using the code. The calculation program for the crack propagation of fatigue and stress corrosion crack (SCC) has been developed in accordance with the operating procedure of the code. The calculation time for out put the life of fatigue (or SCC) is a few minutes. The initial crack depth probability distribution and the probability of detection for crack in pipes have been investigated for support of management of plant pipe life. The developed support program can estimate the reasonable replace time of pipe by using of Probabilistic fracture mechanics (PFM).

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This study treats the reduction of the degree of the passenger injury by analyzing the behavior of the passenger sitting on a box seat at the time of the collision outbreak of the railroad carriage by simulation. Judgment the degree of the passenger injury was enabled by development the behavior analysis program of the passenger with C language and inputting a decelerating acceleration wave pattern at the time of the vehicle collision obtained by the finite element analysis. Injury judgment values decreased by more than 30% by optimizing to assume the spring constant of the seat as a design variable to reduce an injury judgment value.

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The main objective of this research is to present a technique of vibration measurement and control with a simple system. First, the simple vibration measurement system is constructed with a small number of accelerometers and band-pass filters. The accelerometer is placed on the optimal placement and used as modal sensor. The optimization approach based on the minimization criterion of observation spillover is adopted. Second, we discuss the feasibility of the simple measurement system through numerical simulations and experiments for an aluminum cantilevered plate. Finally, numerical simulation of vibration control, which is adopted a feedback control scheme using the measured modal information by modal sensor, is also presented. To suppress vibration, PZT piezoelectric materials are used as modal actuators. Some numerical simulations and experiments validate the accuracy of vibration measurement and vibration control with the proposed simple system.

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A gradient-based method for global optimization of nonlinear programming problems, named "Modal Trimming Method," has been proposed. It has shown that the capability of global search is because the renewal of the values of variables based on an extended Newton-Raphson method creates a chaotic behavior. However, this method also creates periodically-vibrating behaviors, which result in a significant defect. An extended secant method has been adopted in combination with the extended Newton-Raphson method, and it has turned out that this strategy has a tendency to avoid the periodically-vibrating behaviors and promote the chaotic behavior, which can enhance the capability of global search. In this paper, the modal trimming method with this strategy is applied to a variety of test problems, and its effectiveness is clarified in terms of computational efficiency.

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This paper describes recent activity in JAXA aiming reformation of design and development (D & D) process by introduction of information technology, simulation technology, reliability engineering, etc for rocket valve reliability improvement. In this activity, JAXA's information system for rocket valve D & D will be developed by the end of FY2007. This information system consists of detailed FMEA/FTA utilization support tool, QFD utilization support tool, and material database system and material database utilization support tool. This information system will help to improve efficiency and reliability of D & D process of JAXA's rocket valves and other JAXA's products.

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In order to improve an efficiency of failure analysis process by using failure mode and effect analysis (FMEA) and failure tree analysis (FTA), detailed FMEA/FTA support tool is developed. By using this tool, failure mechanisms can be analyzed with FMEA approach as well as FTA approach. In order to improve coverage of the extracted failure modes, new failure analysis approach is proposed, which is based on the interface N2 chart. Interface N2 chart is N2 chart which is extended to express the interface of mechanical system. Interface N2 chart can also be used to visualize the failure analysis result to describe system structure based on the knowledge obtained in failure analysis such as causal relationship of fault propagation. New schematic visualization method is discussed to realize useful visualization tool which promotes comprehensive understanding of failure mechanism.

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Fault tree analysis (FTA) is a method to analyze and visualize causes of some fault event by expanding a fault event to its cause events hierarchically and making a tree diagram representing the entire structure of the problem. When a designer finds or encounters some problem during a product design and development process, it is an effective way of achieving security and safety of the product to identify all possible causes of the problem by FTA and fix them. Although FTA is an effective method, it is not easy for a designer to make complete fault tree without any misunderstanding or oversight. In this paper, we propose a computer aid for FTA, such as consistency check of fault tree and node expansion advice, based on quantity dimension indexing.

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The design of mechanical products is a complicated process, due to the large number of design variables and performance characteristics, so it is difficult for design engineers to obtain global optimum solutions. This paper proposes an optimization method for such product designs in which hierarchical product optimization methodologies are constructed based on simplification of the optimization problem. We simplify design variables and/or performance characteristics, and arrive at simplified optimization problems. The subsequent optimizations are started at the lowest, simplest levels of the hierarchical optimization structure, and proceed to higher levels. Simplification facilitates obtaining global optimum solutions and clarifies the focal issues of the optimization problem. Some applied examples demonstrate the effectiveness of the proposed method.

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This paper shows the design methodology of the transportation system when On-Demand Bus system is introduced. With this method, the most appropriate number of the On-Demand Bus is defined and inefficient route buses to be abandoned are estimated. According to the result of simulation, transportation network in Kashiwa city become more efficiently from the view point of the CO_2 reduction and customers' satisfaction with the On-Demand Bus service.

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In our previous research, we developed the two-stage design method consisting of topology and shape optimizations for the effective and practical design of complaint mechanisms. However, in this method, the designer has to manually convert the result of topology optimization to an initial shape optimization model and such task takes a lot of time and is hard work for the designer. To resolve this problem, we develop a procedure to automatically create an initial shape optimization using level set method.

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In these days finite element method is often used to design and develop products effectively. Using it engineers can evaluate the impacts of design changes without any experiments, so the method which can analyze dynamic characteristics of the much changed structure rapidly is required. Yamazaki and Hagiwara developed the new perturbation method with complementary term for this purpose and showed the possibility to reduce the analysis time drastically, but this method causes the extreme slowing down and instability problems when the structure changed widely. Here, we propose the new complementary vector compute method and the way to calcurate responses effectively to solve these problems, and evaluate the accuracy, calculation speed and stability of these methods.

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In this paper we investigate three dimensional optimized Schwarz methods for the numerical solution of urban acoustic pollution within a city. Optimized Schwarz methods are using new transmission conditions which are then optimized for the efficiency of the Schwarz algorithm without overlap. We perform several calculations in three dimension on parallel computer and compare the speed and accuracy of the optimized Schwarz methods without overlap equipped with three dimensional zeroth order and second order transmission conditions. We show that the optimized Schwarz method applied to large scale exterior acoustics problems is strongly robust and scalable.

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Today, more lightweight and more stiffness structure member is needed because of environment concern. Especially, for vehicle car this issue is very important. So, we try to enhance diamond core panel which is first developed by Dr. Nojima in order to be substituted for car door panel. This panel is derived from the theory of filling plane with certain geometrical figures. We evaluate its bending characteristic through the non-linear dynamic simulation. And we select design variables of Diamond Core Panel which affect its bending characteristic very much. Using these variables we try to optimize the configuration.

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In this paper, a simple and efficient numerical method to connect two plates by spot welding in the finite element analysis is presented. By only given the finite element mesh of two plates to connect and coordinate of the connection points, constraint equations to express the connection in the spot welding are generated. Based on the present method the computer module has been developed to generate the constraint equations for spot welding. Numerical examples are demonstrated.

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In this paper, a simple and efficient mechanical model and numerical method are presented to solve the dynamic behavior of ballast used in the railway track. The geometry of a crushed stone is expressed by a polygon defined triangular patches. A simple mechanical model is given to express the contact-impact behavior among crushed stones. Based on the present method, a computer program BALLAST has been developed to solve the dynamic behavior of ballast. A numerical example is demonstrated.

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In this paper, an efficient numerical method for the transient boundary element acoustic analysis of the railway structure is given. A railway structure is modeled with the same structure block connected repeatedly in the rail direction. For a block structure the transfer matrix C(ω) at frequency co from the nodal velocity vector to acoustic pressure vector on the boundary surface is obtained by using BEM. The approximated time response of acoustic pressure at arbitrary points around the structure to the vibration of the railway structure is effectively obtained from the transfer matrix. Numerical examples are demonstrated.

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Shape optimization problem of a hinged-clamped beam that is subjected to a concentrated load is reconsidered. Previous report had said that the actual most suitable form within the same volume exists only in the case that the load was in a hinged end side of the span. In this paper, the problem is solved by an iterative method that uses numerical integration. Through numerical examples the characteristics of the optimum solution and the problems in numerical calculation are discussed.

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In PSO, swarm evolves toward better life by making greater diversity of swarm. We know it from many numerical experiments. In this paper, we will propose Multi-Swarms Agent PSO. We allow giving multi-swarms to Agent PSO developed by us, allowed different parameter settings for each individual. We will be able to get better result because of greater diversity of parameter settings.

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One of the aims by the population based optimization techniques is to find a global minimum. In this paper, The Adaptive Range Particle Swarm Optimization (ARPSO) to find multiple optima is proposed. The active search domain range in the ARPSO is only one, however, the proposed approach has many search domain ranges to find multiple optima. Initially, many the search domain ranges are generated by the paired particles, and the procedure of the ARPSO is performed. Many search domain ranges are sometimes integrated through the search process. The detail procedure to integrate the search domain ranges is also explained in this paper. It is possible to find multiple optima with high accuracy by the proposed approach. The validity of proposed method is examined through numerical examples.

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This paper reports the survey on the Multi-Objective Particle Swarm Optimization (MOPSO). Some MOPSO models have been proposed since 2002. The objectives of the MOPSO are summarized as follows: (1) To find the pareto optimal solutions, (2) To find the pareto optimal solutions as diverse as possible. We summarize these MOPSO, and point out some merits and demerits.

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The objectives of the Multi-Objective Evolutionary Algorithms (MOEA) are summarized as follows: (1) To find the pareto optimal solutions, (2) To find the pareto optimal solutions as diverse as possible. To achieve these objectives by the PSO for the single objective problems, we propose how to define the g-best in the swarm without introducing some new parameters. That is, one particle among the non-inferior solutions is selected as the g-best to achieve the divesity among the non-inferior solutions. The relative distance in the objective space is utilized to select the g-best among the non-inferior solutions. Additionally, some particles among the non-inferior solutions are also selected as the g-best of the inferior solutions to find the pareto optimal solutions. The absolute distance in the objective space is utlized to select the g-best of the inferior solutions. We also show the geometical interpretation about the movement of particles. The validity of proposed approach is examined through typical numerical examples.

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Service Engineering is a new engineering idea which aims at increasing service and knowledge contents of added value generated in product life cycle. In this paper, we introduce Service CAD (Computer Aided Design) system, which supports designers to design a service in our proposed method. At first, we arrange the architecture of the development system mainly on the technique we suggested and think it about a future line of investigation.

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The authors have developed an integrated design-support tool of product and service, called Service CAD system. In general, design solutions obtained with current Service CAD frequently have various kinds of contradiction. Such contradictions make it difficult to practice services. The quality and efficiency of design largely depend on how rapidly designers can find out and solve such contradictions in design solutions. Contradictions in service-product design have been classified in consideration of design processes and existing cases. In this paper, the authors introduce a detailed methodology of supporting design, which enables designers to find out the existing contradictions in design solutions and obtain the basic strategies to solve them on computers.

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In order to achieve the circulation type product life cycle, it is necessary to realize a good balance between environmental and economical efficiencies in business. The purpose of this study is to propose a methodology for helping a designer to generate business ideas to change existing business into environmentally conscious business (eco-business). The generation of business ideas can be divided into two stages, divergent thinking and convergent thinking. Therefore, this methodology is to support these thinking stages. In divergent thinking stage, the general rules for increasing and for reducing costs are used. In convergent thinking stage, from economical and environmental viewpoints, many business ideas are narrowed down.

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A modularization design is effective method in order to keep coexistence of environmental consciousness and variety of product. However, very long time is required to start a function of life-circulation, so that a market could change greatly in the meantime. This is one of the major reasons that a judgment of a good or bad modular structure is not easy for the designer. In order to solve this problem, two methodologies are required: (1) a prediction method of the change of the market in long life span of the product family, and (2) a design method of the life-cycle and module structure based on the predicted market change. The aim of this research is to develop a method of the ability to design the optimal modular structure considering life cycle calculation based on the sales scenario defined by the plan and prediction of the sales of the line-up products in the product family. This paper assumed that the market change is modeled as a number of the product soled. Based on this assumption and change of the quantity of the sales products by the change of the customer requirements and the competitive products in market are modeled as a sales scenario of a product family. An example is validated for effectiveness of the proposed method based on the proto-type system.

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Modular design is an important elemental design technique in life cycle design. Modularity may increase maintainability, upgradability, and so on. Appropriate modular structure differs according to applied life cycle options; e.g., while the modular structure for recycling should be based on material kinds, the structure for upgrading should be based on functions to be obsolete. However, from the technical aspect, since most existing methods employ connectivity of components and do not use geometric information, they may derive unrealistic modular structure. For solving these problems, this paper proposes a modular design methodology that utilizes life cycle option, geometric model, and connectivity of components. The life cycle options classify the components into some groups that should trace the same life cycle and the geometric information and the connectivity are employed to derive a feasible module structure within the group. This paper also illustrates a case study using a printer. This case study reveals that the methodology derives geometrically consistent modular structures flexibly depending on life cycle options.

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We have been developing Part agent system to support the maintenance of products where each network agent manages the information of the corresponding part. In this report, we propose a technique with which a part agent calculates the state of the corresponding part based on the information of the part, operation history of the product and recall information provided by the manufacturer, and decides if the part should be recalled or not. For this purpose, a method is developed to generate a simplified model including only the related parts in the product and to estimate the state of the part. Application to a recall case of exhaust pipe of automobile using 1 dimensional vibration model is investigated.

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Parts that are collected for disposal differ in quality due to their various usage and operational environments. Some of them may function well and can be reusable. In order to manage individual parts throughout their life cycle and to promote their reuse, we are developing Part Agent system consisting of network agents that follow their corresponding parts and RFIDs attached on them. This paper describes the basic functions of a Part Agent to control RFID. They were implemented in a prototype system that supports the replacement of small computer parts based on the varied user's requirement.

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The current maintenance system of a house is not effective for all of houses because living environment and sense of value are becoming various. For this problem, Visualization of a condition of a house would be effective to use sensor networks. Expressing the deterioration of a house with using causation is effective. And catching behavior of a house numerical value as properties of matter value is effective too.

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Service Engineering has the model to describe service contents between a provider and a receiver in the form of parameters. Service designers can clarify the influence on service receiver using the model. In general, service has plural stakeholders, and customer requirements are gradually realized by these agents. Therefore some parameters in different models could have relations according to the continuous delivery process. However, there is no model to describe the relations between different models. In this paper, we propose a method of integrating information on service models based on relations of entities.

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