• Journal of Advanced Marine Engineering and Technology
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• 제38권2호
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• pp.225-232
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• 2014

The traditional RAP (Redundancy Allocation Problem) of complex systems has considered only the redundancy of subsystem with homogeneous components. In this paper we extend it as a RAP of complex systems with heterogeneous components which is more flexible than the case of homogeneous components. We model this problem as a nonlinear integer programming problem, find its optimal solution by tabu search, and suggest an example of the efficient reliability design with heterogeneous components. In order to improve the quality of the solution of the tabu search, we suggest a modified tabu search to employ an adaptive procedure (1-opt or 2-opt exchange) to generate the efficient neighborhood solutions. Computational results show that our modified procedure obtains better solutions as the size of problem increases from 30 to 50, even though it requires rather more computing time. With some adjustment of the parameters of the proposed method, it can be applied to the optimal reliability designs of complex systems of ships.

• 한국CDE학회논문집
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• 제6권2호
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• pp.140-146
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• 2001

A nuclear Power Plant is composed of a number of mechanical components. Maintaining the integrity of these components is one of the most critical issues in nuclear industry. In order to evaluate the integrity of these mechanical components, a lot of data are required including inspection data, geometrical data, material properties, etc. Therefore, an effective database system is essential to manage the integrity of nuclear power plant. For this purpose, an internet based virtual reality environment and web database system was proposed. The developed virtual reality environment provides realistic geometrical configurations of mechanical components using VRML (Virtual Reality Modeling Language). The virtual reality environment was linked with the web database, which can manage the required data for the integrity evaluation. The proposed system is able to share the information regarding the integrity evaluation through internet, and thus, will be suitable for an integrated system for the maintenance of mechanical components.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.639-643
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• 2005

본 논문은 컴포넌트 검색을 위한 정보저장소 구조를 설계하였다. 정보저장소는 컴포넌트 검색을 위한 구문분석, 검색방법, 뷰어, 재사용으로 연결시킬 수 있도록 데이터, 프로세스, 뷰어로 구분하여 구성하였다. 컴포넌트 검색은 개선된 스프레딩 액티베이션 알고리즘을 이용하여 그 결과를 뷰어를 통하여 보여준다. 검색 결과는 우선순위가 높은 순서로 검색되기 때문에 재사용의 효율성이 높다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제12권4호
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• pp.308-318
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• 2012

Captions include information which relates to the images. In order to obtain the information in the captions, text extraction methods from images have been developed. However, most existing methods can be applied to captions with a fixed height or stroke width using fixed pixel-size or block-size operators which are derived from morphological supposition. We propose an edge connected components based method that can extract Korean captions that are composed of various sizes and fonts. We analyze the properties of edge connected components embedding captions and build a decision tree which discriminates edge connected components which include captions from ones which do not. The images for the experiment are collected from broadcast programs such as documentaries and news programs which include captions with various heights and fonts. We evaluate our proposed method by comparing the performance of the latent caption area extraction. The experiment shows that the proposed method can efficiently extract various sizes of Korean captions.

• 대한가정학회지
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• 제24권1호
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• pp.53-58
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• 1986

In order to study the antioxidative action of the effectient garlic components, peroxidase and superoxide dismutase activity were compared through the in vitro and in vivo experiments. RESULTS : 1. Observing the effects on peroxidase activity of efficient components in vitro, garlic oil, alliin and ethanol fraction showed effective, which was similar to the trend of TBA value, peroxide value and induction time for the first period of lipoperoxide formation in vitro. 2. In vivo experiment with peroxidase activity, the ethanol fraction and garlic oil were effective when intraperitoneally administered as well as orally administered. 3. Considering the superoxide disutase activity in vitro, the garlic oil, alliin and ethanol fraction were effective in efficient components. But non-kaolin fraction inhibited the activity on the contrary. 4. In terms of the efefcts on superoxide dismutase activity in vivo, alliin and garlic oil wee effective in intraperitoneal adminstraton and the ethanol fraction and alliin in oral administration.

• 오토저널
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• 제15권1호
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• pp.107-119
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• 1993

The objective of this study is to analyze the static and dynamic characteristics of automotive rubber components by computer simulation. Bush / rectangular type engine mounts and wind shield weather strip are analyzed by using the commercial code ABAQUS and the results are verified by experiments. Large deformation static response is analyzed in order to get the information about the deformation pattern and static stiffness of engine mounts, and about the seperation force of wind shield weather strip from body. The isothermal steady-state dynamic response of components which have been subjected to an initial static pre-load is analyzed for the dynamic stiffness of engine mount rubber components. There are good agreements between simulation and experiments. So it is possible to apply the computer simulation to the design of automotive rubber components.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
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• pp.570-572
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• 2008

The modulation quality of the I/Q modulator in a wireless transmitter usually affects system performance and it mostly depends on both a nonlinearity and a distortion, from the third order intermodulation($IM_3$) signal and the error components such as an input amplitude error and a local phase error, respectively. This paper focused on how much the Single Sideband Ratio(SSR), which indicates the signal distortion, changes according to the variation of the error components. Consequently, since a desired signal, side band signal at the I/Q modulator output are also represented with those power series coefficients and the error components, the effects of the error components on SSR to meet the EVM specification of the WPAN can be clearly analyzed.

• 대한원격탐사학회지
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• 제26권6호
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• pp.681-691
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• 2010

LiDAR waveform decomposition plays an important role in LiDAR data processing since the resulting decomposed components are assumed to represent reflection surfaces within waveform footprints and the decomposition results ultimately affect the interpretation of LiDAR waveform data. Decomposing the waveform into a mixture of Gaussians involves two related problems; 1) determining the number of Gaussian components in the waveform, and 2) estimating the parameters of each Gaussian component of the mixture. Previous studies estimated the number of components in the mixture before the parameter optimization step, and it tended to suggest a larger number of components than is required due to the inherent noise embedded in the waveform data. In order to tackle these issues, a new LiDAR waveform decomposition algorithm based on the sequential approach has been proposed in this study and applied to the ICESat waveform data. Experimental results indicated that the proposed algorithm utilized a smaller number of components to decompose waveforms, while resulting IMP value is higher than the GLA14 products.

• 대한산업공학회지
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• 제29권2호
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• pp.179-189
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• 2003

Gate poly-silicon critical dimension is a prime characteristic of a metal-oxide-semiconductor field effect transistor. It is important to achieve the uniformity of gate poly-silicon critical dimension in order that a semiconductor device has acceptable electrical test characteristics as well as a semiconductor wafer fabrication process has a competitive net-die-per-wafer yield. However, on gate poly-silicon critical dimension, the complexity associated with a semiconductor wafer fabrication process entails hierarchical variance components according to run-to-run, wafer-to-wafer and even die-to-die production unit changes. Specifically, estimates of the hierarchical variance components are required not only for disclosing dominant sources of the variation but also for testing the wafer-level uniformity. In this paper, two experimental designs, a two-stage nested design and a randomized complete block design are considered in order to estimate the hierarchical variance components. Since gate poly-silicon critical dimensions are collected from fixed die positions within wafers, a factor representing die positions can be regarded as fixed in linear statistical models for the designs. In this context, the two-stage nested design also checks the wafer-level uniformity taking all sampled runs into account. In more detail, using variance estimates derived from randomized complete block designs, Duncan's multiple range test examines the wafer-level uniformity for each run. Consequently, a framework presented in this study could provide guidelines to practitioners on estimating the hierarchical variance components and testing the wafer-level uniformity in parallel for any characteristics concerned in semiconductor wafer fabrication processes. Statistical analysis is illustrated for an experimental dataset from a real pilot semiconductor wafer fabrication process.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권12호
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• pp.1011-1020
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• 2007

독립적으로 개발된 상용 컴포넌트들을 소스 코드 수정 없이 조립하여 재사용하기 위해서는 컴포넌트간 인터페이스 불일치 문제를 해결해야 한다. 본 논문에서는 이러한 문제를 해결하기 위한 새로운 컴포넌트 모델 및 조립 방법을 제안한다. 제안한 컴포넌트 모델은 각 컴포넌트가 서비스를 제공하는 하위 컴포넌트의 인터페이스에 의존하는 대신 서비스 요청에 관한 인터페이스를 독자적으로 정의하여 내장하고 이를 메타데이타로 노출한다. 조립 시에는 컴포넌트들의 요청 및 서비스 제공 인터페이스에 대한 메타데이타를 읽어 글루 컴포넌트 템플릿 코드를 자동 생성하여 인터페이스 정합에 필요한 중재 코드를 삽입하는 구조이다. 또 프레임워크에서 컴포넌트들에 대한 인스턴스를 관리하고 런타임시 의존성 주입 방식으로 조립을 수행하며, 글루 컴포넌트를 미들웨어 서비스 포인트 및 실시간 모니터링 포인트로 활용하는 방안도 제안한다. 이와 한께 본 논문은 제안한 컴포넌트 모델에 따르는 컴포넌트를 개발하고 조림하는 도구를 구현하여, 실용 가능성을 입증하였다.