• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1996.06b
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• pp.61-66
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• 1996

In this paper, an efficient contour coding algorithm incorporating polygonal approximation and discrete sine transform is introduced. Contour information is inevitable in content based coding, and polygonal approximation method is widely used to compress the contour information. However polygonal approximation method is not suitable when fine contour is needed. We show that the error signal of polygonal approximation can be efficiently represented using DST, that is, the contour information can be represented accurately with polygons and DST coefficients. With this contour coding scheme, the required bits to represent a contour can be reduced by about 40-50% with virtually no degradation compared to the existing chain coding method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.786-792
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• 2006

The design of experiment(DOE) with orthogonal arrays is adopted when the engineering design is needed in a discrete design space. In this research, a design process with orthogonal array is peformed to obtain the optimum design which satisfy the frequency target of the steering system. The optimum design is determined from the analysis of means(ANOM) and sensitivity information about design variables is evaluated by the analysis of variance(ANOVA). Interactions between design variables are investigated to achieve additivity which should be valid in using orthogonal array. It is shown that when strong interactions exist, the DOE process with orthogonal array considering interaction is introduced to find out optimum design.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.295-297
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• 2005

본 논문에서는 펩 서비스 기반 시스템에 대한 프로젝트 관리 기법을 소개한다. 먼저 웹 서비스 기반 시스템에서 발생할 수 있는 개발 복잡성이 무엇인지 설명한다. 발생 가능한 복잡성은 클라이언트와 서버 사이의 통신 프로토콜인 XML에서 발생한다. 또한 웹서비스의 갯수가 증가하면 WSDL의 관리도 중요해진다. 본 논문에서는 개발 복잡성을 줄이기 위한 웹 서비스 기반 시스템의 아키텍처는 무엇인지 소개한다. 또한 프로젝트 관리 도구를 사용하여 XML을 관리하는 방법을 소개한다. 마지막으로 이 관리 기법을 프로젝트에 도입하였을 때 어떤 생산성 증가 효과가 있었는지 소개한다.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.206-210
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• 2005

As design trends has changed to have flexible aft hull structure, increased power output and stiffer shafting system, owners and classification societies have more concerned about shaft alignment. In the shaft alignment analysis, there are many uncertainties which are related in propeller generated force, bearing stiffness, crank shaft model and etc. in this study, it is focused on the effect of crankshaft model by comparing between equivalent model and actual crankshaft model.

• Journal of the Korean Society for Nondestructive Testing
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• v.12 no.3
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• pp.33-39
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• 1992

This paper presents a summary of the immersion ultrasonic test to analyze the quality of diffusion bonding parts. The most important property of diffusion bonding parts is bonding strength, and that can be obtained by shear test. By comparing among data obtained by ultrasonic test(C-Scan) and those by shear test (bonding strength), these data are shown to be in good relation. Therefore ultrasonic C-Scan test result can be used successfully in quantitative quality control for diffusion bonded parts.

• Journal of Ship and Ocean Technology
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• v.9 no.4
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• pp.11-22
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• 2005

This paper addresses details of wave load nonlinearity effect on stress RAO and damage ratio using component stochastic fatigue analysis. Traditional spectral fatigue analysis for ship structure is based on linear theory; however, there are a number of nonlinearity sources. Especially loading nonlinearity, such as hydrodynamic pressure applying to ship side and gravity changes due to roll and pitch motion, is thought to critically violate the linearity assumption of spectral fatigue analysis, which involves stress RAO as linear parameter. The main focus is placed on how to idealize complicated characteristics of loading nonlinearity and how to implement the nonlinear bias to linear spectral fatigue analysis.

• Journal of Hydrospace Technology
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• v.1 no.1
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• pp.89-110
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• 1995

The enactment of OPA90 (Oil Pollution Act of 1990) in the USA and the consequent moves by IMO(International Maritime Organization) to introduce new Regulations for the design of oil tankers led the oil transportation industry to undergo a period of big change. This resulted in the introduction of double hull tankers. This paper introduces the design for the 300, 000 DWT double hull VLCC of World-Wide Shipping Agency Pte Ltd. in Hong Kong, which is the first of this type constructed by Daewoo Shipbuilding & Heavy Machinery Ltd.(DSHM). The characteristics of the compartment and structural arrangement of this vessel are briefly described, and the scope of structural analysis is illustrated. In addition, the merits/demerits of different crosstie arrangements are described in the appendices.

• Proceedings of the Korea Water Resources Association Conference
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• 1994.02a
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• pp.411-416
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• 1994

• 한국가스학회:학술대회논문집
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• 1998.09a
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• pp.162-176
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• 1998

• Journal of the korean Society of Automotive Engineers
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• v.31 no.2
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• pp.33-41
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• 2009