• KIPS Transactions on Software and Data Engineering
• /
• v.5 no.1
• /
• pp.1-6
• /
• 2016

Domain analysis is an important component for reliability of development project. Domain analysis error have an effect in the whole system. As a result, the system reliability will be deteriorated. Therefore, we need a methodology to analyze domain characteristic for a reliable analysis in the domain analysis phase. In this paper, we propose a methodology for domain categorization and estimation of complexity for reliability improvement of domain analysis.

• Journal of Applied Reliability
• /
• v.14 no.4
• /
• pp.256-261
• /
• 2014

Solar cells are considered ideal as a clean energy to generate electricity. However, silicon-based photoelectric cells show some shortcomings in efficiency, cost and reliability. This has been a barrier to further commercialization. This paper shows how 40 Inventive Principles can be used in the research and development on the solar cells to improve efficiency, cost and reliability.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.4
• /
• pp.467-473
• /
• 2013

The addition of disconnect switches to a distribution feeder or the replacement of the manual switches with the automatic switches do, in general, increase reliability by decreasing the duration of the outage of many to the customers on the feeder and reducing the outage section. However, the improvement of reliability in power distribution system causes an increase of the investment cost, for example, replacement costs, labor costs, and so on. For this reason - the balance between investment and reliability improvement - many studies about the appropriate level of investment have been conducted. In this paper, we suggest the algorithm for determining the reasonable switch automation rate in the power distribution system. We evaluate the customer interruption cost and reliability for several cases - these cases relate with the switch automation rate - in the domestic metropolitan power distribution system, estimate the effectiveness of changing the manual switch to automatic switch quantitatively. These results can help the determining on the disconnect switch's automation rate.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.3
• /
• pp.49-54
• /
• 2007

신뢰성이란 단기간에 측정되는 성능과는 다른 지표로서 흔히 장기간에 걸쳐 평가되는 품질의 척도이다. Oil Cooler는 공작기계(machine tools)의 주축 및 구동부 등에서 발생하는 열 변형을 제어하는 장치로서 공작기계의 신뢰성 향상을 위해서는 oil cooler의 신뢰성 개선이 이루어져야 한다. 본 연구에서는 oil cooler의 신뢰성 개선을 위해 고장률 데이터베이스를 이용한 신뢰성 예측과 이를 통한 취약부품 분석을 실시하고 신뢰성 시험기를 통한 oil cooler의 신뢰성을 평가하였다. 이를 통해 oil cooler의 정량적 신뢰도를 계산하였으며 신뢰성호 향상을 위한 공정기법을 개발하여 적용하였다. Oil cooler의 신뢰성 개선을 통해 공작기계 및 반도체 제조 장비 등과 같은 제조 시스템의 신뢰성 향상을 기대할 수 있으며, 제안된 기법을 이용하여 다른 기계류 부품의 신뢰성 평가 및 개선에 적용할 수 있다.

• Proceedings of the Korean Reliability Society Conference
• /
• 2000.04a
• /
• pp.223-230
• /
• 2000

This work aims to develop modeling methodology of machine part reliability. The reliability model is to be used for predicting and improving reliability in planning and design processes of products. In order to develop the reliability model of machine parts, the functions and interactions of sub-units of machine parts are analyzed first and function network is constructed. Using the function network, function block diagram is developed, which can be the basis for deriving reliability block diagram. Modeling of machine part reliability has not been widely studied since the reliability modeling of machine parts requires understanding of the functions and failures of their components in several viewpoints. This work tries to find general methodology of reliability modeling and proposes a framework for reliability improvement during machine part development.

• Structural Engineering and Mechanics
• /
• v.51 no.6
• /
• pp.973-988
• /
• 2014

This paper presents a factor-analysis based questionnaire categorization method to improve the reliability of the evaluation of working conditions without influencing the completeness of the questionnaire both in Taiwanese and Chinese construction enterprises for structural engineering applications. The proposed approach springs from the AI application and expert systems in structural engineering. Questions with a similar response pattern are grouped into or categorized as one factor. Questions that form a single factor usually have higher reliability than the entire questionnaire, especially in the case when the questionnaire is complex and inconsistent. By classifying questions based on the meanings of the words used in them and the responded scores, reliability could be increased. The principle for classification was that 90% of the questions in the same classified group must satisfy the proposed classification rule and consequently the lowest one was 92%. The results show that the question classification method could improve the reliability of the questionnaires for at least 0.7. Compared to the question deletion method using SPSS, 75% of the questions left were verified the same as the results obtained by applying the classification method.

• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 2003.11a
• /
• pp.14-14
• /
• 2003

• Journal of Applied Reliability
• /
• v.5 no.3
• /
• pp.381-391
• /
• 2005

The level of reliability attained largely depends upon the investment in reliability growth programs during development phase. In order to find the relationship between reliability growth test time and BRTE(basic reliability tasks effectiveness) in a reliability improvement program that minimizes LCC in which contains the reliability growth cost, repair and replacement costs, and spare parts ordering costs in service with given service rate in management policy, the growth rate has been suggested proper LCC versus growth rate. This model employs the reliability growth projection with delayed fixes in avionic equipment based on AMSAA.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.23 no.56
• /
• pp.1-8
• /
• 2000

We present in this paper an optimal stocking policy for a repairable inventory system under reliability improvement. For this purpose we illustrate commercial flight lines with a large number of planes. This model is supported by a central repair facility. For modeling the nonstationary M/M/s system we implemented SIMAN for computing the time dependent number of units in the repair facility with any number of units. In this model we provide the required inventory level at each location. 1y month. for various levels of associated stock-out risk.

• Journal of Applied Reliability
• /
• v.13 no.3
• /
• pp.217-227
• /
• 2013

Reliability growth is defined as the positive improvement in a reliability parameter over a period of time due to implementation of corrective actions to system design, operation or maintenance procedures, or the associated manufacturing process. In recent, the importance of reliability growth management has emerged in the military authority and industries. For effective application of reliability growth models, it is necessary to understand their characteristics and differences. This paper presents the concepts of reliability growth management and compares the features of reliability tracking and projection models centered on MIL-HDBK-189C for selecting the appropriate model for an one-shot system under development.