• Korean Journal of Computational Design and Engineering
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• v.6 no.2
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• pp.133-139
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• 2001

Since a great number of 2D engineering drawings are being used in industry and at the same time 3D CAD becomes popular in recent years, we need to reconstruct 3D CAD models from 2D legacy drawings. In this thesis, a combination of a feature recognition method and an expert system is suggested for the 3D solid model reconstruction. Modeling primitives of 3D CAD systems are recognized and constructed by using the pattern matching technique of the features modeling. Additional information for the 3D model reconstruction can be generated by extracting symbols or text entities which are related to form entities. For complex and indefinite cases which cannot be solved by the process of feature recognition, an expert system with a rule base has been used for decision-making. A 3D reconstruction system which recognizes 2D DXF drawing files has been implemented where models composed with protrusions, holes, and cutouts can be handled.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.139-142
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• 2005

This paper describes an automatic finite element (FE) mesh generation for three-dimensional structures consisting of free-form surfaces. This mesh generation process consists of three subprocesses: (a) definition of geometric model, i.e. analysis model, (b) generation of nodes, and (c) generation of elements. One of commercial sol id modelers is employed for three-dimensional sol id structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well control led by the fuzzy knowledge processing. The Delaunay method is introduced as a basic tool for element generation. Automatic generation of FE meshes for three-dimensional sol id structures holds great benefits for analyses. Practical performances of the present system are demonstrated through several mesh generations for three-dimensional complex geometry.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.3
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• pp.136-141
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• 2000

This paper presents the design of an H$\infty$ based robust Static Synchronous Compensator (STATCOM) supplementary controller to suppress the subsynchronous resonance (SSR) in the series-compensated system. The IEEE second benchmark, System-l model is employed for this study. In order to design the effective controller, the modal controllability and observability indices to the oscillation modes are considered. Comprehensive time domain simulations using a nonlinear system model that the proposed STATCOM supplementary controller can suppress the SSR efficiently in spite of the variations of power system operating conditions.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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• pp.327-332
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• 2010

It is necessary that End-of-life Vehicle (ELV) should be recycled from the point of view of environmental preservation and resource recycling. This paper deals with two issues. The first one is the basic functional construction and plant layout of the ELV dismantling system that can maximize the reusability of parts and the recyclability of materials. The second issue is the development of a simulation model which can be used to estimate the performance of the layout design. The simulator has been interfaced with an interactive layout design system, and used to effectively determine an optimal layout design of the ELV dismantling system.

• The Journal of Society for e-Business Studies
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• v.6 no.1
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• pp.69-81
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• 2001

No organization can survive in today's modern society of information and high technology without internet and/or intranet. International convention industry is one of many high-technology dependent fields today which have started gathering new attention since the new millennium had begun. According to our survey, no professional convention organizer has used so far any type of integrated information system which is the vital source of support of the convention industry. Only the general purpose office softwares have been in use. The main purpose of this study is to design a model for ICIMS(International Convention Information Management System) to manage all the related information of international convention in a systematic and integrated way and to implement its prototype. International convention system in general had been analyzed to enhance the level of accuracy of the model for ICIMS. A simulation of an international conference was conducted to test the core module of the ICIMS model.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.79-84
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• 1996

The robust controller for the nuclear reactor power control system is designed. The reactor model is set up by use of the point kinetics equations and the singly lumped energy balance equations. Since the model is different from the actual plant, the controller which makes the system robust is necessary. The perturbation of the actual plant is investigated with respect to several possible sources of uncertainty. Then the overall system is configured into the two port model and the $H_{\infty}$ controller is designed. The loop shaping and the permissible control rod speed are considered as the design constraints. The designed $H_{\infty}$ controller provides the sufficient margins for the robustness, and the system output as well as the control input satisfy their relevant requirements.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.326-328
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• 1993

Modelling theory, based on differential equations, is not an adequate tool for solving the problems of complex system. Identification of complex system using GMDH(group method of data handling) is more appropriate for this problems. In this paper, GMDH algorithm is used to identify the nonlinear plant and to design model following nonlinear control system. Simulation for the DC motor show the good performance of model following nonlinear control system.

• Asia pacific journal of information systems
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• v.12 no.1
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• pp.1-16
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• 2002

Most of searching systems used by shopping-mall provide too much information for user requirements or fail to provide appropriate items reflecting customer's preference. This paper aims to design and implement the product searching systems based on customer preference which will enable efficient product selection in the internet shopping-mall. The proposed system consists of user/provider interface, searching and model agent, data management system, and model management system. Especially, we construct the searching pattern database to support fast search using association mining method. And this system includes the customer-oriented decision model which shows the highly preferred products. Input weight value per attribute and preference level should be needed to compute priority grade of preference.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.119-121
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• 1997

This paper suggests a design method of the robust model following PD control system using genetic algorithm. This PD control system is designed by applying genetic algorithm with reference model to the optimal determination of proportional and derivative gains that are given by PD servo controller. These proportional and derivative gains are optimized simultaneously in the search domain guaranteeing the robust stability of closed-loop system satisfying different stability margins. The effectiveness of this PD control system is verified by computer simulation.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.181-186
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• 2000

Recently a strong request for the improvement in irrigation water management in order to flexibly meet the spacial and time changes of water demand for agricultural and other uses by saving agricultural water. Thereby, the purpose of this study is to design of Basin Water Management Program(BWMP). BWMP is operate with Open Control System. Accordingly, BMWP is easy to acquire data and control irrigation and drainage facilities. BWMP are consist of Data Base Management System(DBMS) and Model System. DBMS make it possible to analyze data related with planing for water schedul and establish database. Model System are calculate reservoir inflow, reservoir effluent and basin water demand. Finally, operator is decide reservoir operation in consider of Model System and DBMS. BWMP might be nicely adapted to the planning and decision for saving water.