• International Journal of Reliability and Applications
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• 제2권4호
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• pp.263-268
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• 2001

Shanmugam(1991) generalized the Poisson distribution to capture a restriction on the incidence rate $\theta$ (i.e. $\theta$ ＜ $\beta$, an unknown upper limit), and named it incidence rate restricted Poisson (IRRP) distribution. Using Neyman's C($\alpha$) concept, Shanmugam then devised a hypothesis testing procedure for $\beta$ when $\theta$ remains unknown nuisance parameter. Shanmugam's C ($\alpha$) based .results involve inverse moments which are not easy tools, This article presents an alternate testing procedure based on likelihood ratio concept. It turns out that likelihood ratio test statistic offers more power than the C($\alpha$) test statistic. Numerical examples are included.

• 전산구조공학
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• 제3권1호
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• pp.51-57
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• 1990

현행 원자력 발전 구조물의 설계하중 조합규준은 확률적 개념에 의한것이 아닌 재래적인 설계 개념을 그대로 사용하고 있는 실정이다. 본 연구에서는 원자력 발전 구조물의 설계하중 조합 규준을 FEM에 기초한 랜덤 진동 해석을 통하여 제안하였다. 종래의 일반적 신뢰성 해석 방법과는 달리 유한요소 해석 결과를 랜덤 진동 이론에 결합하여 해석함으로서 지진하중과 같은 각종 동적 하중에 대한 보다 정확한 신뢰성 해석이 가능하게 되었다. 본 연구에서는 설계하중 조합 규준을 통하여 국내 원자력 발전 구조물에 적합한 설계하중 계수를 제안하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.2986-2999
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• 2019

The uncertainties of the uncertain graph make the traditional definition and algorithms on mining dense graph for certain graph not applicable. The subgraph obtained by maximizing expected density from an uncertain graph always has many low edge-probability data, which makes it low reliable and low expected edge density. Based on the concept of ${\beta}$-subgraph, to overcome the low reliability of the densest subgraph, the concept of optimal ${\beta}$-subgraph is proposed. An efficient greedy algorithm is also developed to find the optimal ${\beta}$-subgraph. Simulation experiments of multiple sets of datasets show that the average edge-possibility of optimal ${\beta}$-subgraph is improved by nearly 40%, and the expected edge density reaches 0.9 on average. The parameter ${\beta}$ is scalable and applicable to multiple scenarios.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1994년도 가을 학술발표회 논문집
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• pp.160-166
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• 1994

In general, the problems of strengthening and repairing of deteriorated or damaged reinforced concrete members are usually worked out in situ by externally bounding steel plates using epoxy resins, which has been recognized to be one of effective and convenient methods. But the disadvantages of strengthening/repairing concrete members with externally bonded steel plates include ; (a) deterioration of the bond at the steel-concrete interface caused by the corrosion of steel ; (b) difficulty in manipulating the plate at the construction site ; (c) improper formation of joints, due to the limited delivery lengths of the steel plates ; and etc. Therefore these difficulties eventually have led to the concept of replacing the steel plates by fiber-reinforced composite sheets which are characterized by their light weight, extremely high stiffness, excellent fatigue properties, and outstanding corrosion resistance. In the paper, for the reliability assessment of reinforced concrete beams externally strengthened by carbon fiber plastic(CFRP) laminates, an attempt is made to suggest a limit state model based on the strain compatibility method and the concept of fracture mechanics. And the reliability of the proposed models is evaluated by using the AFOSM method. The load carrying capacity of the deteriorated and/or damaged RC beams is considerably increased. Thus, it may be stated that the post-strengthening of concrete beams with externally bonded CFRP materials may be one of very effective way of increasing the load carrying capacity and stiffeness characteristics of existing structures.

• 대한간호학회지
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• 제27권4호
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• pp.753-764
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• 1997

This study was conducted to develop a sexual satisfaction tool for married women in Korea. The data was collected from July 19 to Aug 18, 1997 by means of questionnaires developed by researchers. The subject were 417 married women living in Seoul and Pusan. The process of this study was as follows : 1) The concept of sexual satisfaction was defined. 2) A conceptual framework was identified based on the extensive review of relevant literature and interviews with married women. 3) The preliminary question items containing the attributes and elements of the concept of sexual satisfaction were listed. 4) The preliminary items were revised after a pilot study. 5) The Index of Content Validity(CVI) was calculated from the content specialists' rating. 6) The reliability and validity of the sexual satisfaction measurement tool were tested. As a result of the item and factor analysis, 17 out of 30 items were found to be valid, consequently could be used to measure sexual satisfaction for married women. These final 17 items were divided into two factors. These factors were labeled as "situation factor" (10 items) and "response factor"(7 items) according to the attributes of the clustered items. The reliability of the final 17 items was .9118. Further research is needed to confirm the reliability and validity of the tool by applying it to a group of healthy married women and to a group of married women having health-related problem.

• International Journal of Advanced Culture Technology
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• 제9권2호
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• pp.106-117
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• 2021

The aim is to find cyber measures in consideration of physical CPTED in order to prepare countermeasures for cybercrime prevention. For this, the six applied principles of CPTED were used as the standard. A new control item was created in connection with the control items of ISO27001. A survey was conducted on former and current investigators and security experts. As a result of the reliability analysis, the Kronbar alpha coefficient value was 0.947, indicating the reliability of the statistical value. As a result of factor analysis, it was reduced to six factors. The following are six factors and countermeasures. Nature monitoring blocks opportunities and strengthens business continuity. Access control is based on management system compliance, personnel security. Reinforcement of territoriality is reinforcement of each wife and ethics. Establishment of security policy to enhance readability, security system maintenance. Increasing usability is seeking ways to utilize, periodic incentives. For maintenance, security education is strength and security-related collective cooperation is conducted. The differentiation of this study was to find countermeasures against cybercrime in the psychological part of the past. However, they approached to find in cyber measures. The limitation of the study is to bring the concept of physical CPTED to the cyber concept.

• International Journal of Reliability and Applications
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• 제2권3호
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• pp.161-187
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• 2001

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms reliability, failure rate, product life, and durability are explained. From the customer's standpoint, the concept of product quality is classified in five factors, according to related technology: performance, reliability, conformance to specifications, customer perception, and fundamentals advantage. The correlation of the five factors for a first-class product is discussed, Since the market share of a company is determined as the competition result of its product value, defined as product quality and price, the market share increase is derived mathematically from the increment of product value. The market share increase, $\Delta$S, can be calculated from the present market share, S, and the oriented relative value increment of new product, R, to the current product in the same company for the same market target: $\Delta$S : $\Delta$(1-S). R/(1+S.R). Finally, the importance of separating warranty cost from the profit equation for the durables is explained.

• Journal of Computing Science and Engineering
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• 제5권2호
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• pp.121-130
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• 2011

Recent research indicates that transient errors will increasingly become a critical concern in microprocessor design. As embedded processors are widely used in reliability-critical or noisy environments, it is necessary to develop cost-effective fault-tolerant techniques to protect processors against transient errors. The register file is one of the critical components that can significantly affect microprocessor system reliability, since registers are typically accessed very frequently, and transient errors in registers can be easily propagated to functional units or the memory system, leading to silent data error (SDC) or system crash. This paper focuses on investigating the impact of register file soft errors on system reliability and developing cost-effective techniques to improve the register file immunity to soft errors. This paper proposes the register vulnerability factor (RVF) concept to characterize the probability that register transient errors can escape the register file and thus potentially affect system reliability. We propose an approach to compute the RVF based on register access patterns. In this paper, we also propose two compiler-directed techniques and a hybrid approach to improve register file reliability cost-effectively by lowering the RVF value. Our experiments indicate that on average, RVF can be reduced to 9.1% and 9.5% by the hyperblock-based instruction re-scheduling and the reliability-oriented register assignment respectively, which can potentially lower the reliability cost significantly, without sacrificing the register value integrity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.394-396
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• 2000

This paper presents a new algorithm for the allocation of the reliability level of composite power system under deregulated electricity market. Under deregulated electricity market, it is required to establish a methodology that can evaluate supply cost and supply reliability of each demand to realize the available priority service reflected a preference of each customer. In this study, a concept of reliability differentiated electricity service as priority service to keep reliability of particular customer within a desirable level is proposed on HLII under deregulated competitive electricity market. The uncertainties of not only generators but also transmission lines are considered for the reliability evaluation in this study. The characteristics and effectiveness of this methodology are illustrated by the case studies on MRBTS and IEEE-RTS.

• 한국철도학회논문집
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• 제9권6호
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• pp.739-745
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• 2006

The role of maintenance in railway is going to be extended to improve the reliability of railway system in the aspect of Asset management gradually. In this paper, the meaning of reliability and safety in RCM which has been applied in order to improve the efficiency of maintenance is deduced. And the analysis task of reliability and safely which has been recommended in railway standards such as EN50126 and IEC62278 is reviewed in the aspect of RCM. Finally, the several ways are proposed to apply RCM to railway system through the comparison between the RCM procedure and the analysis procedure for the reliability and safety in railway standards. Hereafter, if the analysis of reliability and safety is performed with the concept of RCM in the beginning of railway business, it will be more efficient to improve the reliability and manage the railway asset.