• Journal of Advanced Research in Ocean Engineering
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• 제1권1호
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• pp.55-62
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• 2015

Floating structure such as tension leg platform, semi-submersible and spar are widely used in field of oil exploration and renewable energy system. All of these structures have the base cylinder support structure which have effective rule in overall dynamic of response. So the accurate and reliable modeling is needed for optimum design and understanding the physical background of these systems. The aim of this article is an analytical discussion on stochastic modeling of floating cylinder based support structure but an applicable one. Due to this a mathematical mass-damper-spring system of a floating cylinder of HAWAII WTG offshore wind as an applicable and innovative system is adopted to model a coupled degrees using random vibration in analytical way. A fully develop spectrum is adopted to solve the stochastic spectrum analytically by a proper approximation. Some acceptable assumption is adopted. The simplified but analytical and innovative hydrodynamic analysis of this study not only will help researcher to concentrate more physically on hydrodynamic analysis of floating structures but also can be useful for any quick, simplified and closed form analysis of a complicated problem in offshore engineering.

• 산업공학
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• 제17권2호
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• pp.233-241
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• 2004

The main subject to become a hub port is automation. The automated container terminal has already operated in advanced ports and it has been planned for the basic planning and operation design in domestic case. The key of automated container terminal is effective operation of both ATC(automated transfer crane) and AGV(automated guided vehicle) which is automated handling equipments. This is essential to productivity of automated container terminal. This study suggests the most optimal method of equipment operation in order to minimize loading time using each three types of effective ATC operation methods and AGV dispatching rules in automated container terminals. As the automated equipment operation causes unexpected deadlocks or interferences, it should be proceeded on event-based real time. Therefore we propose the most effective ATC operation methods and AGV dispatching rules in this paper. The various states occurred in real automated container terminals are simulated to evaluate these methods. This experiment will show the most robust automated equipment operation method on various parameters(the degree of yard re-marshaling, the number of containers and AGV)

• 한국항행학회논문지
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• 제11권1호
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• pp.105-111
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• 2007

본 논문에서는 퍼지추론을 이용하여 워터마크가 삽입될 최적의 부 대역을 결정하는 방법을 기술하였다. 제안한 방법은 퍼지추론 및 대조도 등과 같은 인간의 시각시스템도 고려하였다. 먼저 시각시스템과 통계적 특성을 활용하여 최적의 계수 대역을 설정하였고, 외부환경 변화에도 대응할 수 있는 퍼지 추론기를 설계 하였다. 비가시성과 워터마크의 정확도를 실험한 결과, 대조도는 스므드 영상에서 우수하였고, 러프한 영상에서는 통계적 특성이 우수함을 보였다.

• 한국도서관정보학회지
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• 제19권
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• pp.35-57
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• 1992

This study is an attempt to provide some helpful data for the design and the implementation of the expert system for the book-classification based on the analysis of various cases of the classification-expert system models. Following the introduction, the concepts and some features of an expert system were overviewed in the second chapter, on the basis of which the following concrete cases were introduced and analyzed in the third chapter : (1) ACN System for NC, (2) Expert System for NDC, (3) Expert System for UDC, (4) Herba Medica System, (5) Expert System for IPC, (6) Stratcyclode Project, (7) Expert System for Classification of INIS Database, (8) AutoBC System, and etc. In the conclusion, for the development of the classification-expert system, it was turned out that constructing a new system by using an AI language such as Prolog or LISP is more desirable than employing any one of expert system shells. Together it is necessary for the following requirements to be met : (1) The subject concept of a document elicited should be accurate. (2) Not only a domain knowledge but also the knowledge covering all the subjects should be represented in the knowledge-bases. (3) The knowledge-bases should be organized in such a way that the characteristics of the knowledge about classification should be well defined. (4) rule-base consisting of accurate rules about classification should be made. (5) It should be possible for classification code wanted to be generated immediately.

• 한국정보통신학회논문지
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• 제19권4호
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• pp.871-876
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• 2015

현재의 웹은 점점 늘어가는 데이터로 인해 효율적인 검색과 관리가 어려워지고 있다. 이를 개선하기 위한 방법으로 시맨틱 웹 기술이 개발되고 있다. 그러나 현재 사용되는 검색시스템들은 시맨틱 웹 기술을 도입하지 않음에도 압도적인 국내 사용률을 독점하고 있다. 이로 인해 시맨틱 웹에 대한 개발은 활성화 되지 않고 있으며, 검색시스템을 사용하는 사용자들 역시 시맨틱 웹의 사용률이 저조한 실정이다. 이에 본 논문에서는 현재 사용되고 있는 검색시스템을 분석하고, 제안하는 시스템의 온톨로지 구현 시 사용자가 사용한 데이터의 종류와 웹 서버의 게시판 사용 시 사용한 파일의 종류를 RDF 표현 규칙에 추가 설정하여 사용자 중심의 검색시스템을 설계 및 구현하였다.

• Transactions on Electrical and Electronic Materials
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• 제9권4호
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• pp.163-168
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• 2008

Photonic crystal structures have been received considerable attention due to their high optical sensitivity. One of the techniques to construct their structure is the dip-pen lithography (DPN) process, which requires a nano-scale resolution and high reliability. In this paper, we propose a two dimensional photonic crystal array to improve the sensitivity of optical biosensor and DPN process to realize it. As a result of DPN patterning test, we have observed that the diffusion coefficient of the mercaptohexadecanoic acid (MHA) molecule ink in octanol is much larger than that in acetonitrile. In addition, we have designed and fabricated optical waveguides based on the mach-zehnder interferometer (MZI) for application to biosensors. The waveguides were optimized at a wavelength of 1550 nm and fabricated according to the design rule of 0.45 delta%, which is the difference of refractive index between the core and clad. The MZI optical waveguides were measured of the optical characteristics for the application of biosensor.

• 한국자동차공학회논문집
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• 제4권2호
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• pp.80-89
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• 1996

Fatigue life of a notched shaft was evaluated in order to estimate the durability and integrity of the notched shaft in design stage. Cumulative fatigue dama- ge analysis was performed using local strain approach based on the assumption that the fatigue life of a notched component is approximately same as that of a smooth specimen is subjected to the same strain at the notched component. In this paper, shafts with different notch root radius of 1, 2㎜ resulting in different values of stress concentration factors were tested under||rotating bending fatigue loading condition. Theoretical stress concentration factor for each notch type was calculated using finite element method. Fatigue life prediction program, FALIPS, written in C language was developed using the strain-life curve, and the local strain approach integrating Neuber's rule, cyclic stress-strain, and hysteresis loop equations. The fatigue life evaluated using the fatigue notch factor obtained from the experimentally determined fatigue strength showed very large scattering with nonconservatism, but the fatigue notch factors derived from the stress concentration factors and Peterson's equation reduced the considerablely accurate fatigue life evaluation within a factor of three.

• 한국항공우주학회지
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• 제31권6호
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• pp.61-71
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• 2003

터보제트엔진 모델에 대한 제어에 있어서, 비교적 잘 설계된 PI 제어기 성능결과를 바탕으로 Takagi-Sugeno형 뉴로-퍼지 추론계를 통한 플랜트 모델의 제어 시스템을 규명함으로서, PI형 T-S 퍼지규칙들을 퍼지제어기를 설계하였다. 이렇게 설계된 제어기의 성능을 향상시키기 위하여, 각 퍼지규칙들을 퍼지 C-Means Algorithm으로부터 각각의 목적 함수군으로 분류한 후, 각 분류군에 대해 규칙간의 가중치가 각 목적함수의 만족도에 부합되도록 하는 기법을 제시하였고, 이를 잘 설계된 T-S형 퍼지제어기에 적용하여 성능을 향상시킴으로써 그 유용성을 보였다.

• 대한전자공학회논문지
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• 제27권3호
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• pp.31-39
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• 1990

입력 디코더(decoder)가 달린 AND-EXOR형 PLA(programmable logic array)의 간단한 문제는 다치(Multiple-Value)입력 2치 출력 함수를 표현하는 ESOP(배타적 논리화를 이용한 적화형 논리식)의 간단한 문제에 대응한다. 본 논문에서는 5종류 적항의 변형 규칙(rule)을 이용한 ESOP의 간단한 알고리듬을 제안한다. 본 알고리듬에 의해 많은 산술회로의 데이타에 대해서 간단화를 행하였다. 그 결과, 1비트 입력디코더 및 2비트 입력디코더가 달린 PLA의 어느쪽에도 같은 예로써, AND-OR형 PLA 보다 AND-EXOR형 PLA의 쪽이 적은 적항수로 실현될 수 있었다.

• 한국컴퓨터정보학회논문지
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• 제9권4호
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• pp.71-76
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• 2004

개정된 국어 로마자 표기법의 기계적 변환을 위하여 웹 기반하의 컴포넌트를 설계하고 구현하였다. 특히 음운법칙을 적용하여 소리글자로 변환 후 로마자 표기로 자동 변환하는 과정과 전사법 변환에 관한 알고리즘을 제시한다. 컴포넌트는 웹 서버의 스크립트 메커니즘에 의해 작동하도록 하였고, 예외어 사전 등은 웹 서버 내부 혹은 외부에서 지원하는 보조 기능으로 설계하였으며, 전체적인 시스템 구조는 UML 명세서와 의사 코드를 이용하여 작성하였다. 제안된 구조는 웹 컴포넌트 형태의 캡슐화 서비스를 제안함으로써 소프트웨어 개발의 경제성, 라이브러리 재사용 및 확장성 등을 향상시킬 수 있을 것으로 기대된다.