• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.123-126
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• 2002

A proposed multi-layer ceramic (MLC) chip type band-pass filter (BPF) is presented. The MLC chip BPF has the benefits of low cost and small size. The BPF consists of coulped stripline resonators and coupling capacitors. The BPF is designed to have an attenuation pole at below the passband for a receiver band of IMT-2000 handset. The computer-aided design technology is applied for analysis of the BPF frequency characteristics. The passband and attenuation pole depend the coupling between resonators and coupling capacitance. The frequency characterics of the passband and attenuation pole are analysed with the variance of the coupling between resonators and coupling capacitance. An equivalent circuit and structure of MLC chip BPF are proposed. The frequency characteristics of the BPF is well acceptable for IMT-2000 application.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1170-1172
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• 1999

HALS(Hypermidia Aided Learning System) is very useful computer networking educational system in high information society, and was developed by Kyungwon University. This system has three characteristics; 1) face-to-face learning, 2) ultra-high-speed information networking, 3) web-based hypermedia courseware. So, the purpose of this paper is to introduce the application to university educational program(electrical engineering: electric power system, control system). For this purpose it is described the definition and characteristics of HALS. Next, it is represented the model of electrical engineering educational program applied to HALS and the developed courseware.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.167-170
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• 1997

For the optimal net shape forging of semi-solid materials (SSM), it is important to predict the deformation for variation of strain rate. It should be necessruy to conduct a formation of stress-strain curve in semi-solid alloys for analysis of the thixoforming process. Particularly, important problem to application of computer aided engineering in SSM processing is to prevent a segregation of liquid component during compression process. The liquid segregation is studied as multistage change of the strain rate and test piece size to prevent the liquid segregation during the compression process. The compression test for semi-solid aluminium alloy with a controlled solid fraction is performed by dynamic material test system with a furnace. Moreover morphology of structure and fraction of pore are investigated through compression test.

• Proceedings of the Korea Society for Simulation Conference
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• 2004.05a
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• pp.57-62
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• 2004

그레이팅(Grating)이라는 금속제품을 생산하는 5 업체에서는 설계 자동화 시스템인 GDS(Grating automatic Drawing System)를 통해 전체 설계도면(Plan Drawing)을 생성하고 GDS의 도면자료 자동생성 시스템(ASGS: Automatic Specification Generation System)을 통해 전체 도면상에 배치된 각각의 그레이팅에 대한 상세한 정보가 표현된 단품별 도면과 완성된 제품들에 대한 검사 기준을 표현한 검사도면을 생성하며 전체 제품에 대한 통계적인 정보를 생성한다. 그러나 도면자료 자동생성 시스템을 통해 자동 생성된 도면은 설계자들의 일반적인 치수 기입요령을 부분적으로 만족시키지 못하고 있으며 또 치수 표시간의 겹침 현상이 발생하여 설계자가 도면을 수정해야하는 번거로움이 있었다. 본 논문은 이러한 문제점을 해결하기 위해, 설계 전문가들의 치수 표시법을 지식으로 하는 규칙 기반 전문가 시스템을 구성하였다.

• Proceedings of the Korea Society for Simulation Conference
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• 2004.05a
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• pp.72-76
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• 2004

CAD (Computer-Aided Design) 시스템은 보다 정확한 공학적 분석과 보다 많은 설계 대안을 고려하므로 설계의 질을 증가시킨다. 이러한 과정 중에 수행되는 최적화에는 다양한 탐색 기법들이 사용되고 있다. 그레이팅 설계를 자동화하는 AutoCAD 기반 시스템인 GDS(Grating automatic Drawing System)에서도 다양한 탐색 기법들이 최적화를 위해 사용되고 있다. 실제 그레이팅의 설계 공정에 있어서, 그레이팅은 특정 제약 조건과 우선순위에 맞추어 배치되어야한다. 그러나 현 GDS는 이러한 조건을 만족하는 최적 해를 찾는 것을 보장하지 않는다. 그러므로 본 논문에서는 그레이팅 배치에서 준수해야할 제약 조건과 우선순위를 만족하는 최적 해를 찾기 위한 하용 가능한 $A^{*}$ 알고리즘을 GDS에 적용하며, 시뮬레이션을 통하여 균등 비용 탐색과 상대적인 효율성을 평가한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.753-756
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• 2000

The accumulated know-how and trial-and-error procedures are known as the best ways to determine blank shape and dimensions. One of the most important steps to determine the blank shape and dimensions in deep drawing process is to calculate the surface area of the product. In general, the surface area of products is calculated by mathematical or 3-D modeling methods. A blank design system is constructed for elliptical deep drawing products to recognize the geometry of the product in the long side and short side by drafting in another two layers on AutoCAD software. This system consists of input geometry recognition module, 3-D modeling module and blank design module, respectively. Blank dimension of three types is determined by the same area, which was acquired in 3-D modeling module. The suitability of this system is verified by applying to a real deep drawing product.

• Genomics & Informatics
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• v.5 no.1
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• pp.24-29
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• 2007

Computational virtual screening has become an essential platform of drug discovery for the efficient identification of active candidates. Moleculardocking, a key technology of receptor-centric virtual screening, is commonly used to predict the binding affinities of chemical compounds on target receptors. Despite the advancement and extensive application of these methods, substantial improvement is still required to increase their accuracy and time-efficiency. Here, we evaluate several advanced structure-based virtual screening approaches for elucidating the rank-order activity of chemical libraries, and the quantitative structureactivity relationship (QSAR). Our results show that the ensemble-average free energy estimation, including implicit solvation energy terms, significantly improves the hit enrichment of the virtual screening. We also demonstrate that the assignment of quantum mechanical-polarized (QM-polarized) partial charges to docked ligands contributes to the reproduction of the crystal pose of ligands in the docking and scoring procedure.

• Asia pacific journal of information systems
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• v.9 no.2
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• pp.19-37
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• 1999

Computer aided process planning(CAPP) is a key for implementing CIM. It is bridge between CAD and CAM and translates the design information into manufacturing instructions. Generally, manufacturing is an area where intelligent systems will not be able to rely on methods requiring formalized knowledge. Manufacturing lacks a body of knowledge that is specific, formalized, and rigorous, and which can be coded as rules or procedures. Thus expertise in manufacturing is developed over a period of many years. Case-based reasoning(CBR) offers a new approach for developing intelligent system. In the case-based approach the problem solving experience of the experts is encoded in the form of cases. CBR's retrieval process can be divided to two step. The first step is matching step, and the second step is selection step. For selecting base case, new preference heuristics were introduced using similarity concept. Similarity concept has three has three dimensions, i.e. entity similarity, structural similarity, and goal similarity. In this paper, bolt's process planning was selected an application domain. Following the test result, the new preference heuristics were approved as a useful procedure in CAPP.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.579-584
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• 1999

The purpose of the present paper are not to develope machine tools of new concepts and advanced mechanisms but to introduce and apply new methods and concepts in the design procedure by using and changing the previously existing technologies. In this paper 3D modeller was proposed for designing machine tools and the design and the better manufacturability checking than 2D one so that design error was dramatically reduced. As designer may easily understand the real shape of a part and assembly object, it's easy to draw the drawings not only in a conceptual design but also in a detailed design. Also, design automation software enabled designer to consider the real important design parameters by reducing time to spend in estimating and calculating the strength of the model by the computer aided automatic calculation instead of a tedious and complex calculation by manual method and help him to easily make the decision for selecting the stocks and design the structure of part or unit of machine tools.

• Journal of the military operations research society of Korea
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• v.24 no.2
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• pp.170-186
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• 1998

The purposes of this paper are applying the IDEF(Integrated DEFinition), which was selected for standard methodology of CALS(Computer-aided Acquisition and Logistic Support) process modeling, to the acquisition process of the weapon system to activate DEfense CALS of the acquisition and management business of weapon system on Defense Planning and Management System and developing a AS-IS model which is usable and that the analysis of process problems results in. On this paper, We diagrammed the function of the acquisition and management of weapon system by using IDEF0 and presented AS-IS model. This paper focused on the development of AS-IS model which can put to practical use to find the problems of current acquisition and management process of weapon system and the embodiment of national defense CALS system. So more detailed analysis of current system and additional studies about TO-BE model would be the future research area.