Window pane with optical multilayer coatings is able to control the solar energy by means of the multiple interference of light. On the one hand, the window glass with multilayer coatings takes on an unintended color that is influenced by spectral transmission in visible range. It is important to design the color according to user's own preferences for residential usage, but it is difficult to evaluate the color from the spectral transmission factor. In this paper, the color through the optical multilayer coatings is analyzed and visualized, furthermore the optimum structure of the multilayer coatings is designed to satisfy the appropriate solar energy control and the user's sense of the color.

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Aluminum beverage bottles with a screw top of 28-mm and 38-mm in diameter have been launched on to the Japanese market recent years to meet new drinking custom trend of the consumers. However, some Japanese customers feel that the 28-mm opening is too small and also feel the 38-mm opening is too large. Therefore, we need to develop a method to evaluate human feelings when drinking directly from the bottle opening and to identify the opening size that is best for consumers' drinking ease. Hence, we propose an evaluation function of drinking ease in order to identify the rigorous dimension of opening diameter. We define the evaluation function of drinking ease in terms of difference between the actual flow amount from the bottles and the appropriate flow amount. If the difference decreases, the consumers possibly feel comfortable. We consider three variables (the bottle opening size, the beverage amount in the bottles, and the height of subjects) and construct the evaluation function of drinking ease using Radial Basis Function Network. Results from the optimization of the proposed function, the subjects may get the closest beverage amount to the appropriate amount and feel comfortable when they drink from the 34.4-mm opening. We have identified the rigorous dimension of the opening diameter from which the subjects may feel comfortable using the proposed function.

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This paper has studied factors that affect consumer's feeling when opening and griping an aluminum beverage bottle, and suggests a method of evaluating opening and gripping ease. Gripping ease of three different kinds of shell diameters (φ50, φ60, φ70) has been evaluated by using semantic differential (SD) method of Kansei engineering. As a result, major subjects have evaluated that the opening φ50 and φ60 is easier to grip than φ70. On the other hand, opening ease of an aluminum beverage bottle has been evaluated by measuring grip force and torque. As a result, the torque to grip the bottle in diameter φ60 shows the largest torque than the other diameters.

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With increasing diversification, the standard for value evaluation has changed extensively these days. Not only functions are evaluated, but also such new factors as Kansei, etc are taken into consideration in Japanese design. Emotion is also attracting wide attention in the Western world. But it seems there is a great difference between Kansei which Japanese evaluate highly and Emotion which Westerners talk about. The difference the author notices will be discussed.

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It is difficult to apply the conventional engineering design method from the necessity of the setting of the objective function in the early design process. Therefore, in the past study, an emergent design system that is applicable from the early design process is proposed. In this study, to aim at the extension of flexibility about the material of the deriving form of this system, we introduced the differentiation phenomenon seen in a morphogenesis of organism into this system, and proposed the algorithm that enables the generation of form including fibrous form with a different material property in addition to an existing form element. Moreover, we tried the form generation with a proposed algorithm.

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Emergence property is an idea that population of local agents which obey simple rules of behavior emerges a complex global structure which is not predictable from the rules. Nowadays a number of phenomena in the filed of physics, chemistry, biology, physiology, sociology and information technology are perceived as results of emergence property. In the context of engineering design, emergence property is often referred to a concept of design synthesis. The authors reported an application of emergence property to mechanical analysis of elastic bodies in 2004. In the report we adopted cellar automaton as simulation framework and showed that structural analysis was realized without any global system equations solved. Analysis methods which require a global matrix, such like FEM, FDM, FVM, BEM and so on were not used in the process and purely local calculation emerged global state of stress, strain and deformation of the elastic bodies. In the subsequent report, we also showed an application of topology generation of structure. However, the set of local rules we used has high complexity therefore it inhibited application of proposed algorithm to complex real-world structures. In this report we present a concept of new formulation of the local rules, which aim to apply proposed rules to analysis of real world structures and morphogenesis.

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Appeal of products is changed significantly by requirement definition and conceptual design phases. Quality of product concept, which is result of these phases, depends heavily on creativity of designer or development team. Therefore, it is difficulty that computer-aided system supports a creative and inventive thinking process, to search a creative design solution. To overcome its difficulty, we develop the synthesis approach which combined the Particle Swarm Optimization (PSO) algorithm and the Particles Method of Unified Structured Inventive Thinking (USIT) for supporting to top-down thinking in the problem solving process. Validity of this approach is discussed through the benchmark problem.

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Act of designing is a constructive activity that creates certain objects by putting different things together. However, there is apparently no common ground we can argue about the constructive aspects of the act of designing. In this study, we analyze the constructiveness of the act of designing on the basis of constructive mathematics, especially, intuitionism. In order to clarify the constructive characteristic of the act of designing, we examine in detail the three aspects of constructive activities, namely, "objects to be constructed", "processes of construction" and "semantics of construction" in comparison to the act of proving in the constructive mathematics. Finally, we discuss the normative principles of the constructive design activities that are derived from the argument of harmony in the three aspects of constructive activities.

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It is said that branch systems in nature is optimum structures for many purposes. This paper suggests a new engineering design methodology by utilizing the optimality of branching network in nature such as botanical tree and root systems, animal vascular systems, and so on. By applying the generation method of the branching network, a branch-like cooling channel is constructed on electronic substrate with a certain heat flux distributed on its surface. We have considered the performances of cooling channel of branch system from both methods of CA simulation and an experiment, and have compared with the cooling channel by conventional design.

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We have proposed vibration-suppressing guide rails, which can eliminate the vibration caused by polygonal effect and adopted them in passenger-conveyers (escalators and auto-roads). This report describes that we found out the required installation-accuracy of these guide rails with mechanical simulations in case of misalliment installation.

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A long-life product such as plant or ship is forced to be adaptable to future technology changes, regulations, and environmental changes. This paper proposes a design method of future scenario embedded product as upgrade scenarios for adaptability of various changes during product lifetime. The design method derives a modular structure between platform modules as constant sub-system and option modules as replacement sub-system. The modular structure is calculated based on a future scenario model represented by a network between events and versions, and a product represented model between components and interfaces. A proto-type system is developed and a design example of lap-top computer is designed. The design results indicate that a sequence of the events and branches of the scenario is important for the scenario-embedded modular structure.

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A modular structure recommendation method and component reducing method is proposed for the product family design. A customer requirement and attributes of products are represented as fuzzy set and fuzzy variable based on not only point-base approach but also range-base approach. Based on the fuzzy-based representation of the product and the customer requirement, candidates of product family are calculated by combination of components and consideration of the range. An evaluation method also proposed for clustering of the solutions of product family. A proto-type system is developed and applied for a design of a handy-drill as an example. The design results indicates that the proposed method can reduce the number of components from twenty-three to fourteen, and fifteen percent of a production cost. Based on the clustering of the generated candidates of the product family plan, a modular structure is found as common characteristics in the high-evaluated plans. The designer can get the modular structure as the highly-balanced modules that can satisfy the customer requirements and low-cost. The design example concludes that the proposed method effectively works for finding of the good modular structure in the product family.

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In the product design, a modular design is an effective approach to reduce product complexity and satisfy various customer needs. On the other hand, the modular design has also negative effects. A standardization of interfaces and functionally independent modules cause easy structure for reverse engineering, and sometime derive a violation of product originality and intellectual property by design copy and imitation product. In order to overcome the negative effects of modular design, this paper focuses on a functional / structural complexity of the modularization, and addresses how to protect the originality and property, and prevent the copy, imitation, and technological outflows. Based on proposed modularization method, this paper proposes a design approach considering trade-offs between protection of product quality from copy production and manufacturing cost, and develops a design process for supporting on the computer.

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This research discusses product family design toward its extension to throughtout consideration of commonalization, customization, and lineup arrangement under optimal design paradigm. That is, commonalization is viewed as the operation that restricts the feasible region by fixing a set of design variables related to commonalized components or modules against later customization and final lineup offered to customers. Customization is viewed as the operation that arranges line up by adjusting another set of design variables related to reserved freedom for customer's needs. Their mutual and bi-directional relationship must be matter of optimal design. This paper discusses the mathematical fundamentals of optimal product family design at the view point of throughout design.

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This research discusses product family design toward its extention to throughout consideration of commonalization, customization and lineup arrangemrnt under optimal design paradigm. Following the succeeding report, this paper discusses possibilities of efficiently designing a family of engineering products such as equipment and machinery. Regarding the differences between consumer products and engineering products, the latter has longer lead time in design and development, and the total number of production units in the latter is fairly smaller than one in the former. By reflecting these differences, we propose a design methodology at the view point of throughout design, which is composed of three phases; strategic identification of common subsystems and adjustable subsystems, anticipatory design of the former subsystems prior to individual orders, and adjustment design of the latter subsystems at respectively individual orders. Among these phases, the second phase is essentially important but complicated. A design example of product family of centrifugal compressors is demonstrated for showing the meaning of throuout optimal design.

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Structural design optimization has become an effective paradigm for designing and developing various kinds of products. However, it is not so popular in the electric appliances in spite of their small sizes and relatively simple configurations. This paper first reviews the reason why the paradigm is difficult to be utilized in designing and developing electric appliances based on the individual but practical experiences in utilizing computational design approaches such as CAE-based design and optimization based design methods. It reveals that the identification of design specifications is fairly important as their prerequisites in the field of electric appliances. Then this paper proposes a strategic scheme for systematically identifying specifications for structural design optimization. The scheme is composed of Specification Priority Matrix (SPM), for identifying the antipathetic importance of performance, cost, time and reliability, Failure Mode and Condition Specification (FMCS), for extracting, categorizing and identifying failure modes and their critical ones, Design Approach Tree (DAT), for selecting an appropriate design approach based on the result of SPM and FMCS, etc. Finally, its effectiveness and validity are discussed by studying the past design and development cases.

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This paper discusses the pattern model of communication on team design work aided by the framework of three dimensional CAD. In design process, designer revises the idea many times to content function. The work in progress idea can be shared other designers. Especially, it is more important to refer the work in progress for integral architecture. Because integral architecture needs adjustment of the design parameter of the components. We report the difference of design process for integral architecture and modular architecture. And, we explain behavior models to adjust rapidly the parameters within integral architecture. Designers can behave as these model autonomously, it emerge organization ability adapted to productive development.

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Recently, in various fields, many design support systems by computers have been developed for improvement of design efficiency. In Service Engineering, the design support systems are also needed for service evaluation and service modeling. In the way of a existing study, there is Service Flow Simulation based on Scene Transition Net is a modeling tool to describe discrete/continuous hybrid systems. When a designer uses the existing simulation method, the designer needed decision design parameters. But the decision depended designer's intention. So it is difficult for the designer to decide adequate design parameters. In this paper, to decrease designers' trial and error in evaluation phases, the authors propose a design-value tuning system that searches for design solutions based on Goal Programming to the service modeled with the existing Service Flow Simulator, and test the system's utility in an example.

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In recent years, comprehensive problem solving by a designer has been required as the demand for an artifact grows and complicates more. In the above background, we have proposed Universal Abduction Studio (UAS), a computer environment, which supports a creative design synthetically. However, it is difficult for designers to acquire knowledge in multiple domains efficiently because they have to accumulate the design knowledge by the handwork. Thus far, we proposed Web-based design knowledge information database extension method. In this paper, we propose the conversion method acquired design knowledge information from the resource on Web into knowledge expression for UAS.

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In order to minimize environmental loads and costs during a whole life cycle of a product, adequate life cycle design as well as product design is indispensable. Modular design is an important elemental technique in life cycle design for improving, e.g., maintainability, upgradability, reusability, and recyclability. This paper proposes a method for determining modular structure by evaluating various attributes related to a product life cycle and geometric feasibility of modules. This paper also illustrates the prototype system that implements the proposed method and a case study of a ink-jet printer.

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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 suggest procedure of the system to promote efficiency and improve reliability of the design in the service CAD system. Then we examine the mounted navigation function to reduce the complexity of the operation with the high functional system.

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Recently, some people have problem of foot called splayfoot. The splayfoot is states with less arch than the ordinary people. This symptom may seem not serious. However, it cause pain in walking. And splayfooted people become getting tired easily. Therefore it cause fatigue in daily life. In addition, these symptoms level is depend on the patient. Therefore a commercial arch support produced by same mold is not always suitable for all patients. Thus arch support designed for individual patient is necessary. In this research, we develop ideal arch support for individual patient by using roentgenogram and approximate multi-objective optimization. And we verify the result by using electromyogram.

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Researches of multi-objective optimization using PSO are starting recently. It has a character of multi-point search. Its search engine is simple, as to aim interior division point of personal best and global best which has achieved among groups. It can be applied to indifferentiable problems because it does not use gradient. We proposed Agent PSO in other times. It is able to set parameters for each individual. It can express biotic diversity and reduce difficulty of parameter setting that is fault of existing PSO. Then we proposed Multi-Swarm Agent PSO. It has multi-swarm to set various parameters more than ordinary Agent PSO. We confirmed improved performance. From our past numerical experiment, we understand that biotic diversity is a key to improve performance. In addition, designers require diversity of Pareto solution of Multi-Objective Optimization. In this study, we propose Multi-Objective Agent PSO that is Agent PSO applied to multi-objective problems. We carried out the proposed method in some bench mark tests, and show the effectiveness of the results and from comparisons.

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[in Japanese]

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The RBF Network is applied to the pattern classification problems. The radius in the basis function is one of the important factors, which affects on the ability of classification. We have already proposed the equation of the radius considering the distribution of the sampling data, that can be obtained based on the equation proposed by Nakayama. We compare the accuracy of classification by using two equations, and the validity of the proposed equation is examined through numerical examples.

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The radius of RBF Network is one of the important factors to obtain the response surface with high accuracy. We have proposed the radius on the RBF Network, which can be obtained by examining the radius proposed by Nakayama. Some conditions to obtain the response surface with high accuracy have been proposed. That is, (1) to consider the number of design variables, (2) to consider the number of sampling points, (3) to consider the maximum distance among the sampling points, and (4) to converge uniformly when the number of sampling points are increased. The adaptive scaling technique of the design variables to the uniform convergence is described in this paper, in order to satisfy above four items.

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The aims of the multi-objective design optimization are to find the pareto optimal solutions, and are also to analyze the trade-off between the objectives. The interactive multi-objective design optimization based on the Satisficing Trade-Off Method (STOM) is used in this paper. Especially, the trade-off matrix to analyze the trade-off between objectives quantitatively is introduced. Each element of trade-off matrix consists of the projection matrix of active constraints and the gradient of objective functions.

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In the previous paper, we have proposed the Trade-Off Matrix, which analyzes the trade-off between the objectives. It is possible to determine the new aspiration level by using the trade-off matrix. To obtain the new aspiration level, the compromise point and solusion are defined by using the trade-off ratio. To obtain the compromise point, the designer input the trade-off ratio between objectives and can obtain the new aspiration level. It is also possible to apply the trade-off matrix to the automatic trade-off method, which is a method to determine the new aspiration level. Through typical numerical examples, the validity is examined.

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In this study, a small sized electric vehicle has been designed and fabricated to decrease the vehicle weight, running resistance and the aerodynamic drag. The light weight body was realized by the CFRP frame body and the sandwich body cowl are 40% reduce the weight of the aluminum frame and GFRP body cowl. The three dimension CAD is utilized for the frame body design and the body cowl fabrication. This paper reported on the trial developments of the super economical electric vehicle.

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The Doshisha which is formed by Doshisha University, Doshisha Women's College of Liberal Arts, four Junior-Senior High Schools, one Elementary School and one Doshisha Kindergarten, has been organizing Doshisha Rohm Plaza supported by ROHM for cultivating the mind of media frontier from 2004. At the Doshisha Rohm Plaza, some unique active projects concerning about the media technology have been performed. Each project is formed by some active students and some faculty. There are three kinds of project; one is the project which is proposed and supported by a company or autonomy, second one is proposed by a couple more students who belong to All Doshisha, and the other one is project's support project which helps the all other projects. In this paper, we describe about the objective, organization and works of Doshisha Rohm Plaza Project for five years.

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The kinematic performance of a torsion beam suspension is determined by the elastic properties of the torsion beam. In the design phase, the numerical analysis such as Finite Element Analysis is usually utilized in order to estimate this performance. However, most suspension designers cannot directly perform this analysis because specific skills are required to achieve sophisticated operation. In order to overcome this problem, we developed a design program of the torsion beam suspension based on the concept of First Order Analysis. In this paper, we introduce an optimization method based on the Response Surface Methodology into this design program. Further, we apply this method to the optimization problem of the configuration of the torsion beam and confirm the usefulness of this program.

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The final goal of this research is to propose a cooling pipe system design method of 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 an optimum design method of cooling channel layout in a plastic injection molding die based on the evaluation of warpage to produce precise plastic products and molding cycle time to improve productivity. The numerical simulations, such as injection process, cooling process and ejection process, are implemented to calculate the warpage induced by residual stress and the molding cycle time. A multi-objective optimum design problem is formulated to achieve the warpage reduction and the short molding cycle time, simultaneously. In this formulation, the warpage and the molding cycle time are adopted as objective functions, and the cooling channel arrangement as design variables. The basis vector method is used to change the cooling channel arrangement. The response surface method is applied to reduce the number of numerical simulations in the optimization process. Through two-dimensional numerical examples, it is found the availability of the optimum design method by discussing on the effect of the cross sectional shape of cooling channel for the minimization of warpage.

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Thermal loading factors are critical in diesel engines, since they affect the maintenance of peak performance and operational durability in competitive scenarios, and must be addressed to fulfill market demands for increased power, reduced weight and superior economy. A cylinder head is one of the most critical engine parts because it must endure various kinds of mechanical and thermal loads during a lifetime of operating cycles, and achieving advanced designs currently depends upon sophisticated evaluations of engine component durability with respect to thermal loading. Therefore, structural optimization concerning thermal loading is a crucial requirement for cylinder head designs that must endure thermal loading. In this paper, an application of shape optimization method for cylinder head designs considering thermal effect, which contains shape dependency on temperature distribution in a cylinder head, is reported using finite element method (FEM) and optimization algorithms. In addition, mesh-morphing technology is applied for updating design variables and initial setting of design variables are determined by the design of experiment (DOE).

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A thermo-magnetic motor is able to drive by using heat energy and magnetic energy such as hot spring water and waste heat from power plants instead of the electric power from the outside. In our previous studies, the 3rd experimental thermo-magnetic motor has been developed and succeeded in steady rotation with hot water from 50 degC to 100 degC and cold water from 0 degC to 10 degC. Furthermore, a new type of the thermo-magnetic motor which is integrated the heating and the cooling lines and the magnetic circuits is designed. The heat cycle of the sealing type thermo-magnetic motor is optimized to increase the effective attracting force acting on the temperature sensitive magnetic materials by using the design of experiments method. However, the output power of the developed machine is insufficient for the practical applications. In this study, We determine appropriately the heat transfer coefficient to compute the accurate output power and investigate the cause of the effective attracting force at magnetic circuits and propose new design factors for increasing output power.

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Optical multilayer thin films are used by many optical dvices for appending a filter function. Design of high performance devices is expected by using anisotropic materials in the multi-layer structure. Numerical analysis considered anisotropy of films is required for obtaining the accurate optical characteristics. Formulation of numerical analysis for optical characteristics of uniaxial optical anisotropic multilayer thin films is presented. Optimization program for optimizing film thickness, refractive index and direction of director in each film is developed. Some results of optimum design are reported in this paper.

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In this paper, we discusses a structural optimization method based on the topological phase-field theory using the level set model and Finite Cover Method (FCM) for obtaining mechanical structures that maximize structural stiffness. In the existing structural optimization, structural boundaries are represented implicitly using a level set function, so that the structural boundaries are ill-defined borders on numerical calculation. Therefore, in this paper, the FCM that is one of the mesh-free analysis methods is applied to the structural optimization based on the topological phase-field theory using the level set model, and so, the structural boundaries are represented explicitly. First, the basic concept of the topological phase-field theory and a structural optimization method based on the topological phase-field theory are briefly explained. Next, a new optimization algorithm for a structural optimization based on the topological phase-field theory using FCM is constructed.

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In this paper, we propose a new topology optimization method for designing a soundproof structure consisting of a poroelastic material and an elastic material that directly minimize sound pressure levels inside an acoustic cavity by applying damping capability. The elastic material and the air medium surrounding the soundproof structure are equivalently represented in the expression of Biot's theory. With this method, a new material interpolation scheme for poroelastic materials based on the density approach is also proposed. Several design examples are presented to demonstrate that the proposed method can provide clear configurations of soundproof structures that reduce sound pressure levels within specified frequency ranges.

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This paper describes some problems in case a designer applies shape optimization method to the design of automotive parts. With an example of the weight saving analysis of the steering knuckle, it is explained that closer constraint functions than the design of the trial and error of the designer are required in order to obtain the optimal part which functions correctly. In addition, it is shown that a person in charge of the structural analysis is not able to find out all those conditions and that shape optimization analysis may not go well when experienced designers and experienced test engineers cannot point out the proper constraint functions for the part not to be broken.

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This paper presents an optimization method for the optimal configuration design of shell structures. It is assumed that the shell is varied in the normal direction to the surface and the thickness is constant. The compliance minimization problem is formulated as a non-parametric shape optimization problem. The shape gradient function is theoretically derived considering the variation of the distributed loads on the shell surface. The Robin type traction method is used to determine the optimal smooth shell surface while minimizing the objective functional. The calculated results show the effectiveness of the proposed method for the optimal configuration design of shell structures.

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