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Bellows which is utilized for an expansion joint is being widely used in the exhaust systems of vehicle and the piping system of nuclear reactor plants. A shape optimal design of U and annular-typed bellows under axial loads is presented and the results are compared with the existing ones. A theoretical structural analysis employs existing theory using the energy method for the toroidal section, and symmetrical bending of a circular plate augmented by thick-walled cylinder analysis for the annular plate which connects two toroidal sections. The procedure for shape optimization adopts λ, the ratio of bellows radius to corrugation radius, and the number of corrugation and the thicknesses of the structure as design variables. Different radii are assinged to the inner and outer toroidal sections, and it is permissible to vary the average thickness of the two toroidal sections and the interconnecting annular plate independently.

Vehicle collisions frequently happen at a low-speed. Insurance companies and the RCAR (Research Council for Automobile Repairs) require reducing repair costs and improving occupant safety in a low-speed crash. In order to reduce repair costs in the RCAR test conditions, an energy absorbing device such as the crash box (C/Box) is usually installed. The C/Box is a thin-walled structure attached between the vehicle bumper structure and the side rail. The determination of the C/Box geometry is quite important to absorb the impact energy since the installation space of the C/Box is not very large. In this research, the determination process for the cross-sectional dimensions is proposed to improve the energy absorption efficiency of the C/Box. The proposed process has two steps. First, the cross-sectional dimensions are determined by two ways. One is a parameter study using an orthogonal array and the other is topology optimization.

Axiomatic design is utilized to identify the design characteristics of an On-Line Electric Vehicle and to manage the design information. The On-Line Electric Vehicle, which is being developed at the Korea Advanced Institute of Science and Technology, is a different concept of an electric vehicle from conventional electric vehicles which use the electric power of a charged battery(s). It is operated by an electric power supplied by the contactless power transmission technique between the roadway side and the vehicle. In other words, the power is transmitted based on the principle of an electric transformer. The On-Line Electric Vehicle can overcome the limitations of conventional electric vehicles such as the weight of the battery and driving distance problems. Because designers have little experience and knowledge about the On-Line Electric Vehicle in the developmental stage, an appropriate design guide is needed. The axiomatic approach is employed for the design process.

The functional requirements (FRs) and design equation of a flexible system change in a continuous manner with respect to a variable such as time. An event driven flexible system is defined as a subcategory of the flexible system in that it changes in a discrete space. A design scenario is developed for the event driven systems. The design equation for each event should be defined by using the axiomatic approach and the design equations are assembled to form a full design equation. The design equation for each event can be established by sensitivity analysis. In conceptual design, the design order is determined based on the full design equation. Design parameters (DPs) are found to satisfy FRs in sequence. A design parameter may consist of multiple design variables. In detailed design, the design variables are determined. The occupant protection system is an event driven flexible system because the design matrix and its elements change according to the impact speed.

As world-wide container volume increases and very large container ships emerge as a dominant player in the maritime cargo transport market, functional capabilities of container ports need to be greatly enhanced. To address this problem, KAIST is undertaking a project to design a novel container transport system, namely Mobile Harbor. Mobile Harbor refers to a system that can go out to a large container ship anchoring in the open sea, load and unload containers between the container ship and the Mobile Harbor, and transport them to their destinations. Designing Mobile Harbor presents a number of challenges as with many other large-scale engineering projects, especially at the beginning stage of the project.