This paper describes an identification probrem of the source position of noise. In this research, in order to identify the source of noise, the boundary element method and the extended Kalman filter are used. First, the sound pressure of an observing point is measured. Next, when the position of a sound source is located in an assumed position, the sound pressures of observing point are calculated by the boundary element method, and the position of the sound source which is an unknown parameter is estimated with an extended Kalman filter. The validity of this technique is checked from the result of a simulation.

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Today, machine design using 3D-CAD became common. The software available exceeds 50. However, in most companies and universities, one software is normally introduced and used. There would exist the other software, which could be more adequate to design a required product or structure. It is the thought that we compared 3D-CAD software and tried to design each subject required to use the appropriate 3D-CAD software. At the Kochi University of Technology, design education using 3D-CAD software has been considered in order for students to obtain the ability of design, which can be useful in their society life.

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With the spread of 2D-CAD, the quality of the drawing in a development design stage changes completely, the process of a development design itself can distort with the spread of 3D-CAD, and it is in the tendency which is missed and goes. Then, into the Mitsubishi Electric group, although spread promotion of whole company-3D-CAD is performed since the '96 fiscal year, since the operation education is improved completely, can progress, it has set centering on the direction, the system with an orthodox development design which narrows down operation of CAD to the degree of required minimum is adopted for five days of beginners' class education and the big effect is mentioned since the last fiscal year, it reports here.

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Engineering education is being recognized to be more important to maintain high position in Japanese technology advantage. However, the technology detachment becomes serious among young people. In order to avoid such circumstances, appropriate engineering education systems are being searched. We are designing a CAD/CAE education system with an attempt of combining real and digital mockup concept into an exercising schooling. As a background, we have introduced a new CAD/CAE system including solid modeler (SolidWorks), structure analysis with FEM (DesignSpace) and mechanical analysis system (DDM) for every student. After learning the operation with exercises for 1.5 years, this final exercising lessons are to be learned. As a real product base, we choose LEGO block. The aim of this exercise is to make the student to know the importance of real and digital consideration for any mechanical design.

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This paper discusses the role of design in education. Up to now, design education in Japan has focused its attention on transferring knowledge about how to design, but recently project based learning has been attracting wide attention and PBL is being introduced widely. Certainly, PBL has such advantages as promoting students' motivations and developing their ability of problem solving. And indeed it serves very well for students to learn how they should work together as a team. But from educational point of view, how should we evaluate their activities, especially, if we encourage them to be creative. And what assignments would be good for the purpose? These are open issues to be answered and the author would like to discuss these points.

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People need the design system with low cost, high efficiency, high accuracy, high manipulation, general purpose and so on. We consider that the integration CAD and CAE is the first step to realize such a system. The merits of the integrated CAD/CAE system are that it makes redesign and optimal design easy, that it can produce analytical models effectively in a short time, and that it can change measure and shape of models easily. As a result, we will be able to offer high quality products in a short time with low cost. Our proposed integrated CAD/CAE system is comprised of four parts, that is, CAD, mesh generation, CAE and post-processing. In this article we shall state the outline of those techniques.

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It has been known that using CAE tool is very effective to improve product quality, reduce development cost and time. The general purpose CAE tool is sophistical for CAE professionals, but is too complex for design engineers. Ansys Inc. introduced a CAE application development platform named as AI^*Workbench. AI^*Workbench is based on industry standard technologies and is an open and flexible development tool for vertical application. Key functions and basic features of AI^*Workbench are described, 2 example applications are also introduced. The First Order Analysis concept introduced by Toyota Central R&D, targeting for automotive designers, is realized using AI^*Workbench. Development of a tool for thermal stress analysis in electronic package is reviewed. Some futur directions to CAE application development platforms are also discussed.

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Concept and use of virtual product are studied in order to realize fully integrated next age CAE for development of automobile. A concept of virtual product is introduced using a new modeling approach proposed by the authors. Structural content and construction method of virtual product is presented. It is mentioned how to use virtual product for successful automobile development.

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A concept of dynamics unifying engineering disciplines is put forward. A common expression of governing lows over different specifications as solid, fluid, electrical dynamics is presented. Two kinds of state values, namely flow value and potential value, are introduced as common state values over different engineering fields. New definitions of characteristics such as mass, stiffness, capacitance and inductance are proposed in a common manner directly based on energy theorem. A new approach of modeling is presented based on this dynamics.

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This paper describe on the compatibility of surface data between the CAD-systems that have different logics of surface definition. We propose the method that can be used as the common 3D model data for CAD, CAM and CAE. These data generate the continuous triangle curved surface that has high accuracy of approximation and also reduce the data size compared with STL-data.

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The present paper proposes a novel approach to the determination of moderately complex shapes that satisfy the requirement for lightweight, high stiffness and enough strength. The parameter CD (curvature deviation) which represents the degree of structural shape complexity is introduced. A smoother shape is derived by an evolutional change of CD, while a structural shape is obtained by an iterative change of an allowable stress region based on the fully stressed design. The proposed method has been verified by applying it to the design of a hook.

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Using the mold flow analysis program, manufacturers of plastic products take advantage in reducing the conventional cut-and-try approach. However, there are two big problems in terms of efficiency. Firstly, only professional staff can operate such programs, and secondly, there are many operations to get good results. So we developed the automatic analysis system on plastic injection molding process and applied it to the exterior parts of TV. Consequently, we reduce man-hour by about 50% compared to before.

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To study the sound field of a structure-acoustic coupling system, numerical analysis techniques are often used. But numerical analysis techniques are not fit to clarify systematically the features of the sound field. In this paper, an attempt is made to clarify systematically the features of the sound field in a rectangular parallelepiped with a flexible panel at one end. First, experimental study is conducted using an experimental model. Its eigenfrequencies, mode shapes are measured, and features of the sound field are discussed. It is found that in the response there is a fixed state, which is unaltered by a modification of the structure. Secondly, theoretical study is made using a one-dimensional mathematical model. It is found this model can explain all the features obtained experimentally.

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In a previous paper, to clarify features of the sound field of a structure-acoustic coupling system, a rectangular parallelepiped with a flexible panel at one side is analyzed. From a practical viewpoint, a parallelepiped with many flexible panels is also important. In this paper, a rectangular parallelepiped with two flexible panels in opposite sides is considered. First, experimental study is conducted. Two features worth noting are found. One is that there is in the response a fixed state, which is unaltered by a modification of the structure. The other is that the sine modal shape can exists, whose existence is confirmed in the usual structure only when its both ends are open. Then, theoretical study is made using a one-dimensional mathematical model. It is found this model can explain the features mentioned above.

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In previous papers, to clarify features of the sound field of a structure-acoustic coupling system, a rectangular parallelepiped with one or two flexible panels are analyzed. From a practical viewpoint, a parallelepiped with flexible panels and with some additional masses is also important. In this paper, a rectangular parallelepiped with a flexible panel and with an additional spring mass system is considered. First, experimental study is conducted. Two features worth noting are found. One is that such mode exists, in which the flexible panel does not vibrate. The other is that a fixed state, whose existence is confirmed in the previous papers can be removed. Then, theoretical study is made using a one-dimensional mathematical model. It is found this model can explain the features mentioned above.

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Bench tests were conducted for idealized pipelines of a hydraulic power steering system in order to obtain data for oil pressure and vibration characteristics. A FEM fluid-structure coupled analysis simulating this bench test was performed. An effective modeling method showing good correlation with measured data for the frequency range of interest of a hydraulic pipeline system containing texture reinforced high pressure rubber hose was developed.

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E-learning systems used for education in various environments have been developed. Some of the systems utilize satellite line and/or special devices. Currently, however, none of them could realize real-time transmission of data, voice and bidirectional interlocking movement of animation for multiple users. In this study, we aim at developing a system based on the existing Internet, by which the real-time transmission of data, voice and bidirectional interlocking of animation can be realized.

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Considering pedestrain and/or low speed Vehicle collision problems, it is effective to get deformation as much as possible along with comparatively small load. These problems are supposed to be axis crash problems, so it is important how to make accordion-like folded patterns. Therefore in this research, we use the idea of the Origami Model. We find several kinds of structure, which can be folded completely. Then, we examine the characteristic of structure, which is possible to be certified with finite element method simulation.

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This paper describes a vibration analysis of an automobile engine by the eigensolver, called CGCGPI method, of ADVENTURE Cluster. The analysis is performed, as a pioneering work on NVH problem, for a motorcar's 4-cylinder gasoline engine, which consists of three components : an engine block, a clutch housing and a gear case. First, the eigenvalue analysis, then substructure synthesis analysis finally, frequency response analysis is conducted.

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A structural optimization method is proposed for designing energy supply systems in consideration of the discreteness of equipment capacities. The structural optimization problem is formulated as a large-scale mixed-integer linear programming (MILP) problem with binary variables for selection and on/off status of equipment, and continuous variables for energy flow rates of equipment. This problem is solved by extending a decomposition method for the problem with continuous equipment capacities. Through a numerical case study, it turns out that the proposed method generates a suboptimal solution for a suitable structural design with a reasonable computation time.

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Despite a recent need for the improvement of train crashworthiness, few design methods have been proposed. To establish it, we tried to introduce the concept of "Crushable Body Structure in automobiles" to the design of train bodies in the past reports. There a train car with crushable zone was modeled by lumped nonlinear springs and masses system. Here characteristic curve of draft gear as to approximate is adopted to real train more exactly, and optimized. In the optimum design, sum of weighted deceleration of the trains was taken as an objective function to be minimized. Then we used 3-cars train model and crush speeds were set to be 15km/h, 25km/h, 35km/h. Optimum characteristics characteristic curve of draft gear is shown. The robustness for velocity is also shown. We introduce and discuss relation of between absorbed energy and decelerations.

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Topology optimization has been successfully extended to a variety of dynamic problems such as the eigenfrequency maximization problem. In this paper, we shall discuss a method for obtaining optimal topologies for vibrating structures that have desired eigenfrequencies and eigenmodes, in order to successfully create mechanical resonator designs. First, the optimization problem is formulated, where the multi-objective functions consist of the square of residuals between desired multiple eigenfrequencies and eigenmodes, and the current ones. The optimization algorithm is constructed based on the grand structure approach and SLP (Sequential Linear Programming). Next, the characteristics of generated optimal solutions are examined using spring-mass and plane truss structural models. Finally, we clarify details among the numerous existing local optima and the effect that a volume constraint has upon the values of the objective functions.

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As CAE (Computer Aided Engineering) applications become increasingly precise, the knowledge and technical skill required to operate such application has become more highly specialized. Such tools have not been utilized in the initial design process of mechanical products, where designers cannot construct detailed analytical models. This paper proposes a cross-sectional shape design optimization system that supports the initial design process for bar structures. The cross-sectional design problem is formulated as an eight-objective optimization problem that can be solved using genetic algorithms. A method for generating cross-sectional shapes satisfying designer-required characteristics is also proposed. These methods, which reduce the number of trial and error process and product design failures, are expected to enable shortened product development lead-times.

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In order to carry out the structural optimization for large-scale structures such as automotive whole body, the authors have proposed the hierarchical optimization method by applying substructure synthesis approach. It gives the relationship between eigenvalues of the whole structure and those of the component structures, which can substitute the large scale optimization problem to the small scale optimization problem. This paper examines the structural optimization problem of floor panel, where lay out of additional frame is decided so that eigenvalues of floor panel coincide the designated values. The eigenvalues of the floor is given by forementioned hierarchical optimization approach.

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This paper focuses on the high-speed distributed collaborative engineering environment via Main Memory Database (MMDB). MMDB is a new type of database system implemented on the semiconductor main memory. Because of its random and high-speed access ability to the data, MMDB is also expected as the platform of concurrent engineering systems sharing the same data among the physically distributed computers. The characteristics, possibilities and merits are discussed and engineering examples are proposed.

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The concurrent engineering has been gradually introduced into the manufacturing industry for the last decade. The concurrent engineering system requires that several processes should access and renew product model data in parallel. Since these processes are often conducted at different branches or sections, it is necessary to deal with the product model data in distributed environment. This paper proposes a new method of constructing a distributed database for manufacturing support, and reports the prototype system implemented based on our concept.

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In design of machinary, computers are very useful and many jobs are aided by computer system and treated more efficient than before. Under recent sever economical environment, cost-benefit becomes important and many computer systems are developed for the sake to do jobs efficiently. Computer networks is the result of the ARPA project and now, this becomes important infrastructure. The success of the design system using computer networks becomes the key-point of the success of the bussiness and design of the product. In this fundamental examination, the authors have developed the design system for the design optimization under computer networks and tried to apply for the simple numerical examples.

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Nowadays, commercial CAD packages with knowledge base systems which support creative design activities are released in succession. However, it is a new burden for the designer to input knowledge to the knowledge bases. In this paper, we propose our idea to generate design rules from design documents written in natural language that are accumulated in enterprises to manage design knowledge, and we also propose a design rule generator implemented based-on our idea. This design rule generator not only reduces the burden to input the rule codes to knowledge-base CAD, but also facilitates design knowledge management, because it is easier for the designer to compose and manage the documents than the rule codes.

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As opposed to highly centralized present systems, cellular-type machines were proposed. A cellular-type machine is a mechanical system composed of distributed autonomous intelligent units, called cells, of as few kinds as possible, and with no central control. In our most recent work, we have introduced the concept of movable cells (cells with the introduction of moving function) as a method to improve the robustness against faults and the flexibility of the previously developed system. In the present work we describe the development of a (movable) cellular manufacturing system, which presents characteristics such as real-time scheduling, self-assembly, and enhanced robustness against faults.

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Although design support systems have been well developed in geometric and detail design areas, they are still not successful in conceptual or creative design domain. In our opinion, the main difficulty is knowledge and its operation that play a crucial role in conceptual design. In this paper, we propose "Universal Abduction Studio" that is a new approach to support designers by computers, and discuss technologies to realize it.

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In the apparel business, most interesting issue is the prediction of consumer's needs. But it is difficult, because trends in a marketplace are changing constantly. In this paper, we propose an online virtual try-on system with containing two sets of code by two different models to carry out cloth simulation. Furthermore we discuss the method for speeding up calculation.

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We propose a method that efficiently managing and downloading a family of 3D models with similar shapes. In our method, a model is decomposed into a set of cells so that any form-feature of the model can be represented by a combination of the cells. This method allows a variety of 3D models to represent in a single data structure. When the user edits the model on a browser, the system downloads necessary cells according to user's request, and newly downloaded cells are merged into the current model on the client side. Since our system does not apply Boolean operations in run time, the client-side system is very efficient and easy to implement, for example, by using Java.

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Recently, it is crucial to appropriately and compactly represent huge information in various situations. The technology to improve visual recognition is well studied and called "Information Visualization". We consider visualization of a "graph" used for representing relations of items. When a graph is large and complex, the vertices and edges must be laid out adequately; otherwise, the graph becomes hard to read. In this paper, we propose a graph layout method by using curved edges based on a leaf-spring model. Our method is effective to satisfy three aesthetic criteria : moderate distribution of vertices, higher angular resolution, and less curvature of curved edges.

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Department of Social and Environmental Engineering, Hiroshima University offers a Creative Design & Manufacturing Project "Paper Bicycle Project", which is the exercise of building and racing a manpower vehicle made from paper products. The aim of the exercise is not only to encourage the problem definition/solution abilities of students but also to provide them with a comprehensive and stiff understanding of what they learned in classes through the process of design and manufacturing of Paper Bicycle. Presentation meetings are held on several stages of exercise to evaluate the quality and rationality of the achievements. This leads to an improvement of the presentation ability of students also. The post-exercise questionnaire to the students has captured a high evaluation.

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The class utilized information and communication technology (IT) is indispensable to environment for new type of education in future. Because we would expect that the class of interactional style might cause the large effect, each student seems to have a tutor. Making of this content is urgent business. This paper are discussed a class of drawing as an example of class to be able to hear again and again, any time and anywhere on the Web page. This software is introduced 3D-CG animation technology so that it is easy to understand more than a face-to-face class. Each student firstly learns a basis of drawing and produces the solid model of a pyramid cut diagonally based on voluntary learning in this class. A student would judge oneself about that a form of model is correct and its section is plane. A learning method on the web page as this study is prospective one as education of making something precisely.

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Web Based Learning (WBL) using the Internet is increasingly becoming popular in engineering education. Yet, there are very few WBL systems, whether regarding machining, manufacturing, or experimentation, that seem to nurture creativity. The authors developed a novel WBL remote design lab involving the connecting rod of a sterling engine. The remote student designs the connecting rod, which is then machined by a milling machine in the lab. The on-site lab attendant installs the connecting rod on the engine and conducts a trial run, which is viewed by the remote student via internet video. Trial experiments demonstrate that the remote lab facilitates the student's understanding of the sterling engine's mechanisms.

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An efficient approximate method for large scale optimal unit sizing of energy supply systems is proposed based on the following two intuitive hypotheses : (a) optimal equipment capacities exist between minimum and maximum ones obtained by solving partial problems, and (b) for a certain sampling time, if on-off status of equipment for the minimum capacity is equal to one for the maximum capacity, on-off status of equipment for the optimal capacity is equal to those states. By solving small scale problems plural times based on these hypotheses, equipment capacities and utility contract demands as well as systems' operational strategies are efficiently determined to minimize the annual total cost and to satisfy energy demand requirements. Numerical studies on gas engine cogeneration systems installed in a hotel are carried out to ascertain the validity and the effectiveness of the proposed method.

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In the world of product design and manufacturing, when recycling aspect is put into product development, not only the development of recycling technology is necessary, but the establishment of design method for easy-disassembly characteristic and meanwhile maintaining easy-assembly characteristic, is needed as well. In this paper, snap-fit connection is chosen out of various types of connection that highly influent assembly/disassembly characteristics, where the beam of snap-fit is modified by cutting a hollow slot into it, thus, making it reconciles easy-assembly and easy-disassembly characteristics. By studying the effects of hollow slot size and its location on the snap-fit, optimum snap-fit shape for assembly/disassembly is formulated.

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A global optimization method for continuous design variables called as Generalized Random Tunneling Algorithm is proposed. Many global optimization methods have been proposed for the unconstrained optimization problem which is to find global minimum subject to the side constraints only. Proposed method is called as "Generalized" random tunneling algorithm because this method can treat the inequality constraints as well as the side constraints. This method consists of three phases. That is, minimization phase, tunneling phase, and constraints phase. By iterating these phases, global minimum is found. The characteristics of mathematical programming and heuristic approaches are included in the proposed method. Global minimum which may lie in the boundary of constraints is easily found by proposed method. Proposed method is applied mathematical and structural optimization problems. Through numerical examples, the effectiveness and validity of proposed method have been confirmed

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This paper describes traffic simulation by using cellular automata. First existing models for traffic simulation are introduced and, the model proposed in this paper are compared with them in order to discuss the features. FInally, traffic simulation on single-lane road is considered as a numerical example.

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We have proposed an effective pattern recognition method for contour image by extracting general and local features. In this method, firstly object is seen perspectively to identify class and secondly seen in detail to identify individual object. The images in the database must be classified to carry out flexible pattern recognition. This paper describes a method to classify images in the database by using Self-Organizing Maps (SOM) and to determine a prototype each class. And we show the result of applying our system to illustrated insects reference book.

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