• 대한전자공학회논문지
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• 제27권3호
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• pp.131-136
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• 1990

본 논문에서 게이트레벨 회로의 논리 최적화를 위한 논리적 redundancy조사를 가속화하는 새로운 방법을 제안한다. 게이트레벨 회로의 redundancy 조사문제는 테스트패턴 생성문제와 마찬가지로 유한상태 탐색문제로서, 그 실행시간이 탐색의 크기에 의존한다. 본 논문에서는 효율적인 탐색을 위해, '동적 head line'과 'mandatory 할당' 방법을 제안한다. 동적 head line은 redundancy조사과정에서 동적으로 변경되어, 탐색에서의 backtracking 수를 감소기키며, mandatory 할당은 불필요한 할당을 피할 수 있어 탐색의 크기를 줄인다. 특히 이들 방법은 기존의 테스트패턴 생성문제에서 사용한 방법과는 달리, 회로 최적화에 따른 회로의 변경에 영향을 받지 않고 사용된다. 또한, 이들 방법을 기존의 redundancy 조사시스템에 실현하여, 그 유효성을 보인다.

• 대한산업공학회지
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• 제39권2호
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• pp.90-98
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• 2013

The k-out-of-n system with mixed redundancy is defined as k-out-of-n system which both includes warm-standby and cold-standby components. In case that operating components in the system fail and the system needs quick transition of standby components to operation state, the k-out-of-n system with mixed redundancy is useful for decreasing system failure rate and operational cost. Reliability-Redundancy Optimization Problem (RROP) involves selection of components with multiple choices and redundancy levels for maximizing system reliability with constraints such as cost, weight, etc. A solution methodology by using harmony search algorithm for RROP of the k-out-of-n system with mixed redundancy to maximize system reliability was suggested in this study.

• 품질경영학회지
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• 제41권3호
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• pp.413-421
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• 2013

Purpose: System availability and life cycle cost are often used to evaluate the system performance and is influenced by the operation and maintenance characteristic. In this paper, we propose the method to improve life cycle cost and satisfy the target availability through redundancy allocation. Methods: We consider the redundancy is available at all items in multi level system. Thus, we assume that sub-assembly, module, components can be duplicated. Simulation and genetic algorithm are employed to optimize redundancy allocation. Results: Target availability is higher, the life cycle cost is increased. In addition, the items for redundancy are selected at higher level in multi level system if target availability is higher. Conclusion: We could know that target availability affects the duplication number of items and the selection of redundancy items. For further study, we will consider new optimization algorithms to compare with the proposed GA algorithm and improve optimization performance.

• 한국시뮬레이션학회논문지
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• 제11권3호
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• pp.49-58
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• 2002

It takes 2 or 3 months to manufacture memory device. Defect has to exist owing to hundreds of processes. If there are too many defects, the memory has to be rejected. But if there are a few defects, it will be more efficient and cost reducing for the company to use it by repairing. Therefore, laser-repair process is needed for such a reason and redundancy analysis is needed to establish correct target of laser-repair process. The equipment development company had provided the redundancy analysis and each development company had developed and provided separately. So, to analyze the similar type of defects, redundancy analysis time can be very different by the manufacture. The purpose of this research is to strengthen the competitive price and to apply correlation concept in business for reducing the redundancy analysis time to repair the defects

• Communications for Statistical Applications and Methods
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• 제13권2호
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• pp.297-307
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• 2006

Most methods for describing the relationship among random variables require specific probability distributions and some assumptions of random variables. The mutual information based on the entropy to measure the dependency among random variables does not need any specific assumptions. And the redundancy which is a analogous version of the mutual information was also proposed. In this paper, the redundancy and mutual information are explored to multi-dimensional categorical data. It is found that the redundancy for categorical data could be expressed as the function of the generalized likelihood ratio statistic under several kinds of independent log-linear models, so that the redundancy could also be used to analyze contingency tables. Whereas the generalized likelihood ratio statistic to test the goodness-of-fit of the log-linear models is sensitive to the sample size, the redundancy for categorical data does not depend on sample size but its cell probabilities itself.

• Structural Engineering and Mechanics
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• 제59권1호
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• pp.15-36
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• 2016

The components of the seismic behavior factor of RC frames are expected to change as structural redundancy increases. Most researches indicate that increasing redundancy is desirable in response to stochastic events such as earthquake loading. The present paper investigated the effect of redundancy on a fixed plan for seismic behavior factor components and the nonlinear behavior of RC frames. The 3D RC moment resistant frames with equal lateral resistance were designed to examine the role of redundancy in earthquake-resistant design and to distinguish it from total overstrength capacity. The seismic behavior factor and dynamic behavior of structures under natural strong ground motions were numerically evaluated as the judging criteria for structural seismic behavior. The results indicate that increasing redundancy alone in a fixed plan cannot be defined as a criterion for improving the structural seismic behavior.

• 산업경영시스템학회지
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• 제9권14호
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• pp.45-48
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• 1986

This paper studies reliability growth model in redundancy allocation of Parallel-series system in which several series system is linked parallelly, The model is generalized by system redundancy of sub-system that have components redundancy. The stage of components in each sub-system is established differently. At the same time by assigned the different number of constraints to the sub-system, this paper deals with rather practical reliability growth model.

• 한국정보통신학회논문지
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• 제19권12호
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• pp.2828-2835
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• 2015

본 논문에서는 다양한 다중화 모형과 논스톱 포워딩 기능이 네트워크 서비스의 가용도에 미치는 영향을 비교 분석한다. 다중화 모형 중 no redundancy, 2N redundancy, N-way redundancy, N-way active redundancy 모형에 대한 확률적 리워드 네트(Stochastic Reward Net, SRN) 모델을 설계하고, 각각의 모형에 대해 논스톱 포워딩 기능을 추가한 SRN 모델을 설계한다. 확률적 페트리 네트 패키지(Stochastic Petri Net Package, SPNP)를 활용하여 설계한 SRN 모델의 가용도를 구한다.

• 품질경영학회지
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• 제43권1호
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• pp.31-42
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• 2015

Purpose: System consists of a lot of units with coherent function. In design phase, various units could be considered with the same function. In this study, we consider the alternative units with the same function and redundancy allocation to maximize system reliability in multi level system. Methods: The redundancy allocation problem with the alternative units in multi level system is formulated. Memetic algorithm(MA) is proposed to optimize the redundancy allocation problem. In addition, the performance of the proposed algorithm is explained by a numerical experiment. Results: MA showed better results than genetic algorithm(GA) and the convergence of the solutions in MA was also faster than GA. In addition, we could know from experiment that system reliability is increased and the chosen unit for redundancy allocation is changed if cost limit is increased. Conclusion: The chose unit for redundancy allocation is changed as resource constraints. It means we need to consider the alternative units in system design. In the future, we need to consider various problem related to redundancy allocation in multi level system and develop the better method to enhance search performance.

• 전자공학회논문지C
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• 제36C권10호
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• pp.29-38
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• 1999

본 논문은 조합 논리회로에서의 시험 불가능한 결함(untestable faults)을 확인하는 새로운 알고리즘 RICP(Redundancy Identification using Critical-pair Paths)를 제시한다. 조합 논리회로에서의 시험 불가능 결합은 회로의 과잉(redundancy)에 의해서 발생한다. 회로의 과잉은 팬 아웃 스템(fanout stem)과 재결집 게이트(reconvergent gate)의 영역을 분석함으로서 찾을 수 있다. 시험 불가능한 결함들은 임계 경로의 확장된 개념인 임계-쌍 경로를 이용하여 스템 영역을 분석함으로써 확인되어진다. RICP 알고리즘이 FIRE(Fault Independent REdundancy identification) 알고리즘보다 효율적이라는 것을 보여준다. ISCAS85 벤치마크 테스트 회로에 대한 두 알고리즘의 실험 결과를 비교하였다