• Journal of the Korean Wood Science and Technology
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• 제32권5호
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• pp.66-74
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• 2004

내화 성능은 표준 화염 조건에 노출된 목구조물의 안전성 평가를 위한 중요한 기준이 된다. 내화 성능의 기준으로 여러 나라에서 지속 시간과 파괴 시까지의 시간이 사용되고 있다. 본 연구에서는 화염에 대한 신뢰성 설계의 기초 연구로서 화염에 노출된 목재 마루 시스템의 신뢰성 해석이 진행되었다. 해석은 수치 해석적 방법과 결정론적 방법 두 가지를 모두 사용하였다. 두 방법 간에는 큰 차이를 보이지 않았다. 화염에 노출된 마루시스템의 신뢰도는 부재의 변이계수에 크게 의존하였으며 부재의 강도나 하중은 신뢰도에 크게 영향하지 않았다.

• 한국안전학회지
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• 제17권3호
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• pp.123-130
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• 2002

본 논문은 사고관리방안 수행에 있어서 발생되는 인적오류의 정량적 평가방법을 개발하여 공동범람 사고관리방안의 예제문제에 적용한 연구결과를 기술하고있다. PSA에서 사용되었던 기존의 인간오류평가 방법론인 THERP, HCR, SLIM-MAUD 방법의 특징을 검토하여 장단점을 기술하였다. 본 연구에서 제시하는 인간오류평가 방법론은 신뢰도물리모델을 이용하는 새로운 HRA 분석방법이다. 불확실성 분석을 위하여 MAAP 코드와 LHS 코드가 사용되었다. 본 연구를 통하여 제안하는 방법은 매우 유연하여 중대사고관리방안과 관련한 다양한 인간오류행위에 대한 평가에 사용될 수 있음을 보여주었다.

• 대한기계학회논문집A
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• 제30권8호
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• pp.985-992
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• 2006

Many methods for reliability analysis have been studied and one of them, a moment method, has the advantage that it doesn't require sensitivities of performance functions. The moment method for reliability analysis requires the first four moments of a performance function and then Pearson system is used for the probability of failure where the accuracy of the probability of failure greatly depends on that of the first four moments. But it is generally impossible to assess them analytically for multidimensional functions, and numerical integration is mainly used to estimate the moment. However, numerical integration requires many function evaluations and in case of involving finite element analyses, the calculation of the first fo 따 moments is very time-consuming. To solve the problem, this research proposes a new method of approximating the first four moments based on kriging metamodel. The proposed method substitutes the kriging metamodel for the performance function and can also evaluate the accuracy of the calculated moments adjusting the approximation range. Numerical examples show the proposed method can approximate the moments accurately with the less function evaluations and evaluate the accuracy of the calculated moments.

• 한국소음진동공학회논문집
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• 제24권1호
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• pp.35-44
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• 2014

Sound pressure levels in the receiving room while testing airborne sound insulation performance are varied by the measuring points. This may increase the measurement error, then decrease the measurement reliability. With this reason the research has carried out on the method to reduce deviations of sound pressure level in the ISO type rectangular laboratory focusing on the measurement of airborne sound insulation performance. Tests were made to see the effect of sound absorption in the receiving room, loudspeaker locations, microphones locations and flanking transmission path. Consequently, it was resulted that sound absorption in the receiving room and the loudspeaker location have influence on the sound level deviations especially in the low frequency. The microphone location was very important to get measurement reliability. The effective measuring point, which the sound level difference with average sound pressure level is within 2 dB, could yield most reliable average sound pressure level. Therefore it is necessary to find the effective measuring points in the receiving room. Flanking transmission path should be sealed using sound absorber or magnet etc. to prevent from lowering the sound insulation performance.

• 한국컴퓨터정보학회논문지
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• 제24권6호
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• pp.45-55
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• 2019

The purposes of this paper is to draw a conclusion on the impact of the characteristics of economic cooperation between china and south korea on customer value and enterprise performance in the korean electronics industry. In this paper, product reliability and product innovation are especially used as analytical factors, and this paper used a survey of 293 internal employees working in the electronics industry for analyze, and structural equation model(SEM) was used to analyze the data. The results of the research analysis are summarized as follows. First, it was found that the characteristic of economic cooperation in the research model has a significant effect on the product reliability. Second, it was found that the characteristics of economic cooperation have a significant effect on the products innovation. Third, the products reliability has a significant impact on customer value, while the products innovation has not affected customer value. Finally, it was found that the customer value of the korean electronics industry also has a significant impact on the Enterprise performance. As a good development alternative to this research, there is the ultimate goal of hoping that corporate managers will help to create new good values. To this end, we hope it will be helpful as we have made necessary suggestions to establish the desired direction of the Korean electronics industry operator.

• 한국신뢰성학회지:신뢰성응용연구
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• 제10권4호
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• pp.265-278
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• 2010

Module of the LED traffic signal is the core component for the care of driver and walker. Also it is important one to control the traffic. If it is against the criteria of brightness, it is the source of the people's death and traffic congestion. Therefore, it is a list of articles desired the security of stability. However, there is not the analysis of failure and not preserve the uniformity of quality. Therefore, it is necessary to establish the criteria of appreciation for the module of the LED traffic signal to analysis the data of failure. In this paper, we investigate the performance test, environment field test and test of reliability appreciation to improve the reliability. We also set up the criteria of success decision using the real measurement data.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권3호
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• pp.208-215
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• 2016

Purpose: ASRP for the domestic development guided missiles requires not only for the reliability evaluation of the products in storage but also for the life cycle management of the products including development prototypes and initial production items. Methods: For this purpose, it should be performed to build a performance database before and after the accelerated aging test with shelf life items including development prototypes and initial production items, based on which the lifetime prediction should also be carried out. In addition, HILS must be applied for the acceptance test with the initial and follow-up production items, and also for ASRP for the long-term storage products in order to secure systematic quality assurance. Results: The results for the life cycle reliability Improving of domestic development of guided missiles are DB building of prescription Item performance, active application of HILS, Management associated with guided missiles life cycle and to Secure technology data about the introduction of foreign guided missiles. Conclusion: Furthermore, it is demanded that DTaQ, the managing agency of ASRP, actively take part in the process to maintain reliability engagement consistency over the life cycle of guided missiles.

• 산업경영시스템학회지
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• 제22권50호
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• pp.23-32
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• 1999

Reliability and maintainability allocation in the analysis of the system's design, with the objective of planning and installing the individual components in such a way that the system performance is achieved. This paper has been made to solve an important task in reliability management of manufacturing systems within the general objective being to increase productivity while maintaining costs low. Thus, the purpose of this paper is to provide an analytical approach to determine an optimal reliability and maintainability allocation, trading off among system performance and parts investment costs. Two important considerations will be addressed in this regard : (ⅰ) determine the reliability and maintainability allocation of parts which maximizes a given production index, having fixed the total cost of investments ; and (ⅱ) determine the reliability and maintainability allocation which minimizes the total cost of investments, having fixed a minimum acceptable level of productivity. The procedure proposed in this paper is able to provide to managers and designers useful indications on the reliability and maintainability characteristics of parts in series -parallel systems. And this heuristic model is a decision support tool for contractors who are involved in large scale design projects such as ship and aircraft design. Numerical examples prove that an approximate expression of the average throughput rate is sufficiently accurate to be used in a numerical optimization method.

• 한국산업융합학회 논문집
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• 제27권3호
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• pp.609-618
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• 2024

System reliability prediction in the development stage is increasingly crucial to reliability growth management to satisfy its target reliability, since modern system usually takes a form of complex composition and various complicated functions. In most cases of development stage, however, the information available for system reliability prediction is very limited, making it difficult to predict system reliability more precisely as in the production and operating stages. In this study, a system reliability prediction process is considered when the reliability-related information such as SIL (Safety Integrity Level) and MTTFd (Mean Time to Dangerous Failure) is available in the development stage. It is suggested that when the SIL or MTTFd of a system component is known and the field operational data of similar system is given, the reliability prediction could be performed using the scaling factor for the SIL or MTTFd value of the component based on the similar system's field operational data analysis. Predicting a system reliability is then adjusted with the conversion factor reflecting the temperature condition of the environment in which the system actually operates. Finally, the case of applying the proposed system reliability prediction process to a high performance mooring platform is dealt with.

• Structural Engineering and Mechanics
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• 제56권4호
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• pp.549-567
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• 2015

A first-order moment method (FORM) reliability analysis is commonly used for structural stability analysis. It requires the values and partial derivatives of the performance to function with respect to the random variables for the design. These calculations can be cumbersome when the performance functions are implicit. A Gaussian process (GP)-based response surface is adopted in this study to approximate the limit state function. By using a trained GP model, a large number of values and partial derivatives of the performance functions can be obtained for conventional reliability analysis with a FORM, thereby reducing the number of stability analysis calculations. This dynamic renewed knowledge source can provide great assistance in improving the predictive capacity of GP during the iterative process, particularly from the view of machine learning. An iterative algorithm is therefore proposed to improve the precision of GP approximation around the design point by constantly adding new design points to the initial training set. Examples are provided to illustrate the GP-based response surface for both structural and non-structural reliability analyses. The results show that the proposed approach is applicable to structural reliability analyses that involve implicit performance functions and structural response evaluations that entail time-consuming finite element analyses.