• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.528-530
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• 1999

This paper addresses the analysis and design of fuzzy control systems for a class of complex single input single output nonlinear systems. Firstly, the nonlinear system is represented by well-known Takagai-Sugeno (TS) fuzzy model and the global controller is constructed by compensating each linear model in the rule of TS fuzzy model. The design of conventional TS fuzzy-model-based controller usually is composed of two processes. One is to determine static state feedback gain of each local model and the other is to validate the stability of the designed fuzzy controller. In this paper, we propose an alternative of the design of TS fuzzy-model-based controller. The design scheme is based on the extension of conventional optimal control theory to the design of TS fuzzy-model-based controller. By using the proposed method the design and stability analysis of the TS fuzzy model-based controller is reduced to the problem of finding the solution of a set of algebraic Riccati equations. And we use the recently developed interior point method to find the solution of AREs, where AREs are recast as the LMI formulation. One simulation example is given to show the effectiveness and feasibility of the proposed fuzzy controller design method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.6 s.177
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• pp.1479-1490
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• 2000

The design process of the motor driven tilt/telescopic steering column is established by axiomatic design approach in conceptual design stage. By selecting independent design variables for improvin g performance of the steering system, each detailed design can be carried out independently. In the detailed design, the safety in crash environment and vibration reduction are considered. An occupant analysis code SAFE(Safety Analysis For occupant crash Environment) is utilized to simulate the body block test. Segments, contact ellipsoids and spring-damper elements are used to model the steering column in SAFE. The model is verified by the result of the body block test. After the model is validated, the energy absorbing components are designed using an orthogonal array. Occupant analyses are performed for the cases of the orthogonal array. Final design is determined for the minimum occupant injury. For vibrational analysis, a finite element model of the steering column is defined for the modal analysis. The model is validated by the vibration experiment. Size and shape variables are selected for the optimization process. An optimization is conducted to minimize the weight subjected to various constraints.

• Journal of the military operations research society of Korea
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• v.3 no.1
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• pp.137-150
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• 1977

The effectiveness of an actual combat tank system is analyzed. A measure of effectiveness which includes performance and reliability called pseudo-reliability is introduced. A model is introduced to optimize the design of the system in which the system pseudo-reliability is maximized subject to cost constraint. This model is a nonlinear programming problem and is solved by the sequential unconstrained minimization technique (SUMT). A numerical exampl with actual data from the test evaluation of five combat tanks is used to illustrate the model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.10a
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• pp.370-376
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• 1997

A Simplified Finite Element Method(FEM) model has been developed for the Exhaust System. For the verification of the usage of the developed model , Natural Frequencies, Mode Shapes and Frequency Response Function have been compared between numerical analysis and experimental result. It shows that the developed numerical model also can be utilized to prove the Stress distribution of the Exhaust System if it can be adopted for the vibration analysis adequately.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.627-630
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• 2001

XML is suitable to integrate various forms of engineering design data since it possesses the characteristics of both documents and data. In this research a web-based design system has been developed, which integrates various gear design data in the form of XML. The system generates XML document containing gear design data and transforms gear design data in the relational database into XML document form automatically. The XML documents are transmitted to gear modeler agent through SOAP, and then the agent is automatically executed and generates CAD model files and VRML files. The designer can check the generated VRML model of gear immediately in the web service.

• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.4
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• pp.43-53
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• 1994

This Study is to construct the Activity System Methods of Site Planning and Design. A planned spaces and facilities is considered usually in relation to users of space and facilities, user attributes, needs and values, and activity patterns. Information obtained form this study adds a qualitative dimension to the quantitative emphasis and supplies information for design-oriented analyses of site planning. In the design-oriented aspect, the concern is with devising desirable land use arrangements and facility supply considering objectives defined in the public interest. The design-oriented approache in site planning and design must use information on activity systems and space qualities in defining planning and design requirements of site development-one in the form of principles and standards of design used in land use and facility planning guidelines, and the other form of input variables for land use model and facility supply model.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.101-105
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• 1989

The iterative learning controller makes the system output follow the desired output over a finite time interval through iterating trials. In this paper, first we discuss that the design problem of learning controller is originally the design problem of the inverse model. Then we show that the tracking error which is the difference between the desired output and the system output is reduced monotonically by properly modeled inverse system if the magnitude of the learning operator being introduced is bounded within the unit circle in complex domain. Also it would be shown that the conventional learning control method is a kind of extremely simplified inverse model learning control method of the objective controlled system. Hence this control method can be considered as a generalization of the conventional learning control method. The more a designer model the objective controlled system precisely, the better the performance of the approximated inverse model learning controller would be. Finally we compare the performance of the conventional learning control method with that of the approximated inverse model learning control method by computer simulation.

• Journal of Korean Society of Steel Construction
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• v.23 no.5
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• pp.637-646
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• 2011

This study is related to the development of a design automation system for the construction design phase of steel structures. The system intended for beam splice friction connections using high-strength bolts. The standard design method and standardization principles that are suggested in the design manual for standard connections using high-strength bolts published by the Korean Society of Steel Construction(KSSC) were reviewed. A structural analysis algorithm was formulated from the review. A design automation system that can automatically calculate the structural design of connections and automatically generate the connection model without separate inputs was developed. To verify the validity of the developed system, its results were compared with the date in the table for the connection design in the Design Manual. The development system was also applied to the sample model. Then the structural design results were compared with the properties of the connection models and drawings created from the results.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.6
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• pp.85-94
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• 2001

Hydraulic systems of rope brake for elevators are modelled to evaluate design parameters such as cylinder pressure, pis-ton displacement, accumulator capacity, and so on. To assure the results, experiments were performed. The analysis results agree well with the experimental results. The scheme in this study is expected to be utilized in the design of rope brake system for elevators to get design parameters and to improve the safety.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.926-931
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• 2001

In this paper a CAD-based optimal design system is introduced and applied to optimal design of machine tool structures. The system is designed to reduce manual interfacing effort. All the design activities such as selecting design variables, making FE meshes and FE analysis are integrated on a parametric CAD program. A user can easily select design variables by clicking a CAD model. To enhance the robustness and versatility, this system uses the finite difference method for the design sensitivity analysis. By taking a practical example of the design of the column of a horizontal machining center, it is shown that the software system is efficiently usable in industry establishing the goal of minimizing user intervention between various analysis and optimization activities.