• International Journal of Quality Innovation
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• 제7권3호
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• pp.15-23
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• 2006

A spare ordering policy is considered for planned maintenance. Introducing the ordering, uptime, downtime, inventory costs and salvage value, we derive the expected cost effectiveness. The problem is to determine jointly the ordering time for a spare and the preventive replacement time for the operating unit which maximize the expected cost effectiveness. Some properties regarding the optimal policy are derived, and a numerical example is included to explain the proposed model.

• Journal of the Korean Statistical Society
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• 제25권4호
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• pp.545-556
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• 1996

In this paper, we introduce a new concept of partial ordering which permits us to compare pairs of the dependence structures of a new hitting times for POD multivariate vector process of interest as to their degree of POD-ness. We show that POD ordering is closed under convolution, limit in distribution, compound distribution, mixture of a certain type and convex combination. Finally, we present several examples of POD ordering processes.

• 대한산업공학회지
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• 제24권3호
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• pp.407-416
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• 1998

For fast Cholesky factorization, it is most important to reduce the number of nonzero elements by ordering methods. Generally, the minimum deficiency ordering produces less nonzero elements, but it is very slow. We propose an efficient implementation method. The minimum deficiency ordering requires much computations related to adjacent nodes. But, we reduce those computations by using indistinguishable nodes, the clique storage structures, and the explicit storage structures to compute deficiencies.

• 대한전자공학회논문지SD
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• 제46권3호
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• pp.32-40
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• 2009

한 제품을 만들어 시장에 내놓는 데 걸리는 시간이 짧아짐에 따라 고속 고장 진단의 필요성이 커지고 있다. 본 논문에서는 고속 고장 진단을 위하여 정렬된 고장 후보 목록과 정렬된 테스트 패턴을 사용하여 고장 점수를 기준으로 고장 탈락을 시키는 방법을 제안한다. 제안하는 고장 탈락 방법은 고장 시뮬레이션과 매칭 알고리듬을 기반으로 하는 모든 고장 진단에 적용할 수 있다. 완전 주사 ISCAS 89 벤치마크 회로를 이용한 실험 결과는 정렬된 고장 후보 목록 및 정렬된 테스트 패턴을 적용한 고장 탈락 방법의 효율성을 보여준다.

• 한국정보과학회논문지:시스템및이론
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• 제30권10호
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• pp.544-555
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• 2003

DNA 마이크로어레이 실험으로 나오는 데이타는 아주 많은 양의 유전자 발현 정보를 담고 있기 때문에 적절한 분석 방법이 필요하다. 대표적인 분석 방법은 계층적 클러스터링(hierarchical clustering) 방법이다. 본 논문에서는 계층적 클러스터링의 결과로 나오게 되는 덴드로그램(dendrogram)에 대해서 후처리(post-Processing)를 시행함으로써 DNA 마이크로어레이 데이타 분석을 더 용이하게 해주는 리프오더링(leaf-ordering)에 대해서 연구하였다. 먼저, 기존의 리프오더링 알고리즘들을 분석하였고, 리프오더링 알고리즘의 새로운 접근 방식을 제안하였다. 또한 이에 대한 성능을 실험하고 분석하기 위해서 계층적 클러스터링과 몇 가지 리프오더링 알고리즘들, 그리고 제안된 접근 방식을 직접 구현한 HCLO (Hierarchical Clustering & Leaf-Ordering Tool)에 대해서 소개하였다.

• 한국과학교육학회지
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• 제12권3호
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• pp.91-107
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• 1992

The Purpose of this study was to present the procedures and methods of ordering theory,and to search for a learning hierarchy among science process skills in each Piagetian cognitive reasoning level. One of the purpose of this is not to determine the clear and exact hierarchy but rather to demonstrate how ordering theoretic methods and procedures can be used to determine the hierarchy of logical relationships among a set of test items or the testing of a hypothesized hierarchy. Ordering theory was used to analyze five science process skills collected from 509 high school students. Ordering Theory has as its primary intent either the testing of hypothesized hierarchies among items at the determination of hierchies among items. Hierarchical relationships were identified within five science process skills. The results will be helpful in giving useful inform at ions to classroom teachers and science curriculum developer.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1990년도 추계학술대회
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• pp.15-18
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• 1990

In abdominal NMR imaging the respiratory ordering techniques have been successfully used to remove the ghosting artifacts arising from the respiratory motion. In the existing respiratory ordering schemes, however, it is generally accepted that blurring of the moving parts still remains as in the signal averaging technique. A new optimal respiratory ordering scheme which can correct the blurring as well as the ghosting artifacts is theoretically derived through the analysis of the phase encoding directional motion effects in Fourier imaging. The performance of the optimal respiratory ordering scheme is experimentally confirmed together with a suboptimal ordering scheme which is suggested as a compromise for the practicality.

• 품질경영학회지
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• 제39권4호
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• pp.480-485
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• 2011

This paper presents a spare ordering policy for preventive replacement with minimal repair. To analyze the ordering policy, the failure process is modeled by a non-homogeneous Poisson process. Introducing the ordering, repair, downtime, replacement costs and salvage value, we derive the expected cost effectiveness as a criterion of optimality when the lifetime and lead times for the regular and expedited orders are generally distributed random variables. It is shown that, under certain conditions, there exists a finite and unique optimum ordering time which maximizes the expected cost effectiveness. A numerical example is also included to explain the proposed model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.6-8
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• 2006

Using enhanced ordering scheme of graylevel in an image, we can apply it to lossless image compression in this paper. The proposed method is ordering scheme to replace an original grayscale image with a particular ordered image without additional information. From the simulation, it is verified that the proposed method reduces the bit rates than plain ordering scheme. And it can be applied in various fields of lossless compression, water marking and edge detection.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2005년도 춘계 학술발표회 논문집
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• pp.161-166
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• 2005

Locus ordering is the necessary step in constructing genetic map, and the construction of reliable and fine genetic map is one of the most important issue in genetic research area. Locus ordering searches for the best locus order among the possible orders and it amounts to evaluating the maximum likelihood for each order. With only 10 loci, for example, there are 1,814,000 possible orders, and therefore, locus ordering entails a big computational problem. In this paper we suggest a useful algorithm for loci ordering via the Fiedler vector. The suggested algorithm is easy to compute and can handle many loci simultaneously. Furthermore, the required computation time is very short compared to others and the result of locus ordering is very accurate.