• 한국신뢰성학회지:신뢰성응용연구
• /
• 제15권1호
• /
• pp.33-43
• /
• 2015

The importance of reliability engineering has increased in recent years. Many studies have been carried out into reliability in a variety of research domains, largely focused on industrial engineering, mechanical engineering, electronics engineering, materials engineering and statistical science. However, most of these studies were carried out without collaboration between different areas of study. Here, we analyze research papers and patents regarding reliability that were published during the past five years, and describe core trends in the development of reliability technology from a multidisciplinary perspective.

• 항공우주기술
• /
• 제2권1호
• /
• pp.205-212
• /
• 2003

신뢰성이란 부품이나 시스템이 얼마나 오랫동안 안심하고 사용할 수 있는가를 정량적 수치로 표현하는 미래의 품질 개념으로 앞으로 제품의 국제적인 경쟁력을 갖추기 위하여 필수적으로 요구되는 기술이다. 국내에서도 제품의 신뢰성 향상에 대한 관심과 필요성이 더욱 고조됨에 따라, 정부에서도 세계적 수준의 신뢰성 평가 인프라를 구축하기 위해 “신뢰성 향상 기반 구축사업”을 적극적으로 추진하고 있으며, 대학, 연구기관 및 전자, 자동차, 중공업 등 수출업체에서 신뢰성에 관한 연구 및 시험평가센터를 설립하여 본격적으로 신뢰성 문제를 다루고 있다. 본 논문에서는 신뢰성 향상 사업에 대한 국내의 현황을 소개하고 항공우주분야에 대한 신뢰성 인증제도 도입의 필요성에 대하여 검토하였다.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제17권4호
• /
• pp.296-304
• /
• 2017

Purpose: Recent weapon systems in defense have increased the complexity and importance of software when developing multifunctional equipment. In this study, we analyze the accuracy of the proposed software reliability model when applied to weapon systems. Methods: Determine the similarity between software reliability analysis results (prediction/estimation) utilizing data from developing weapon systems and system failures data during operation of weapon systems. Results: In case of a software reliability prediction model, the predicted failure rate was higher than the actual failure rate, and the estimation model was consistent with actual failure history data. Conclusion: The software prediction model needs to adjust the variables that are appropriate for the domestic weapon system environment. As the reliability of software is increasingly important in the defense industry, continuous efforts are needed to ensure accurate reliability analysis in the development of weapon systems.

• 전력전자학회논문지
• /
• 제27권6호
• /
• pp.535-540
• /
• 2022

DC-link capacitors are reliability-critical components in a photovoltaic (PV) inverter. Typically, the lifetime of a DC-link capacitor is evaluated by considering the voltage and hot-spot temperature of the capacitor under the specific operating condition of the PV inverter. However, the output of the PV inverter is determined by solar irradiation and ambient temperature, which vary with the seasons; accordingly, the hot-spot temperature of the capacitor also changes. Therefore, the mission profile of the PV system should be considered to effectively evaluate the reliability of the DC-link capacitor. In this study, the reliability of the DC-link capacitor of a three-level NPC inverter is comparatively analyzed with and without considering the mission profiles of the PV system, where two mission profiles recorded in Arizona and Iza are considered. The accumulated damage of the DC-link capacitor is calculated based on the lifetime model by analyzing its thermal loading. Afterward, a reliability evaluation of the DC-link capacitor is performed at the component level and then at the system level by considering all capacitors by means of Monte Carlo analysis. Results reveal the importance of performing a mission-profile-based reliability evaluation during the design of high-reliability PV inverters to achieve the target reliability performance.

• 경영과학
• /
• 제19권2호
• /
• pp.139-153
• /
• 2002

The Analytic Hierarchy Process (AHP) is known as a very useful decision-making model developed for obtaining the relative weights of alternatives through pairwise comparison in the context of hierarchical structure. In this paper, we propose a method to reflect the reliability of evaluators in the process of pairwise comparison. This method is applied to the evaluation of aerospace technology alternatives. We have conducted a questionnaire survey for S company that is one of the representative aerospace companies in Korea. A questionnaire was designed for obtaining both the priority with considering the reliability of evaluators' importance weights (the modified AHP priority) and the priority with assuming equally reliable evaluators' importance weights (the AHP priority) in order to compare the priority derived by each of two methods. The result shows that there exists the difference hard to neglect between the final priorities gained by two methods.

• 산업경영시스템학회지
• /
• 제12권20호
• /
• pp.1-24
• /
• 1989

This paper takes aim at the reliability evaluation by application of Fault Tree Analysis and its computerization. FTA is one of the methods for evaluation of system reliability and safety analysis. The important characteristic of this paper is that computer program is written in the package program(dBaseIII+) by 16Bit/AT personal computer. The program consists of three program segments. (1) The minimal cut sets of the system fault tree are obtained by means of "Fault tree reduction algorithm" (2) The minimal path sets are obtained by inversion of the minimal cut sets determined from fault tree (3) The importance of the basic events which are presented in the minimal cut sets is obtained by means of structural importance analysis. In this paper, a Fault Tree Analysis is applied to a BAG FILTER which is a kind of dust collector.collector.

• 한국기계가공학회지
• /
• 제17권5호
• /
• pp.58-63
• /
• 2018

Recently in weapon systems development, the importance of reliability has been emphasized due to the increase in complexity and the rapid development of key components and components. Accordingly, the importance of lifespan testing is increased. However, lifespan testing to verify the reliability of a system is costly and takes a lot of time. Therefore in this paper, it was demonstrated that the most critical item of a bladder type accumulator is the bladder. Fatigue life is sensitive to temperature and pressure, with temperature having more impact. The fatigue life of the bladder was estimated to be 18,140 hr through fatigue analysis, which satisfies the required life expectancy of 10,000 hr.

• 통상정보연구
• /
• 제11권4호
• /
• pp.215-228
• /
• 2009

This research considers to analyze the importance and priority order of outsourcing partner selecting factors on plant exporters. This research deals with case study on the outsourcing in the "A" plants exporter. To obtain the goal this research, firstly, based on reviewing previous literature and taking professional advice, the selecting factors were identified and conceptualized, and we made the hierarchy model and utilized AHP in analysis method. Secondly, AHP model constructed 3 higher factors, and 9 lower factors. Thirdly, the data used for the weight values for the outsourcing partner factors were collected from outsourcing experts and officers in "A" company. The 3 higher factors were 'Firm's Competence', 'Customer/User Factor', and 'Systemic Factor', and the 9 lower factors were 'experience of outsourcing', 'competency based HR', 'market share', 'reliability', and 'communication', etc. As the results of the analysis, this research evaluated with an importance highest among selecting factors of outsourcing partner of "A" company were 'Customer/User Factor(46.5%)', 'Systemic Factor(27.8%)' and 'Firm's Competence(25.7%)'. And importance highest among lower selecting factors of outsourcing partner of "A" company were 'reliability(31.4%)', 'competency based HR(14.4%)' and 'communication(13.7%)'. The developed model and selecting factors of outsourcing partner are expected to contribute on effective decisions on plants exporters. Managerial implications and future research directions are suggested based on findings.

• 전산구조공학
• /
• 제4권2호
• /
• pp.111-117
• /
• 1991

구조 공학에서의 고유치 문제는 좌굴해석, 진동해석 등 여러분야에 응용되고 있다. 일반적으로 구조물의 좌굴강도 해석에 사용되는 대부분의 변수들은 불확실성을 내포하고 있으므로 확률론적 해석을 수행해야 하지만, 구조물의 좌굴 신뢰성 해석을 위한 극한상태 방정식은 확률변수의 함수로 명확히 표현되지 않으므로 확률 유한 요소법의 사용이 필요하다. 따라서 본 논문에서는 직접미분법에 의해 정식화된 확률 유한요소법을 사용하여 고유치 문제의 신뢰성 해석방법을 정식화 하고, 이를 바탕으로 좌굴 신뢰성 해석을 수행하였으며, 결과의 타당성을 검증하기 위하여 Crude Monte Carlo Method 및 이 방법의 단점을 대폭 보완한 Importance Sampling Method를 사용하였다. 본 논문에 의해 좌굴 신뢰성 해석 방법이 정립됨으로서 신뢰성에 기초한 최적 설계를 수행하는 경우, 시스템 파괴확률로서 소성 파괴확률과 더불어 좌굴 파괴확률의 고려가 가능해졌다.

• 복식문화연구
• /
• 제17권4호
• /
• pp.640-652
• /
• 2009

The purposes of this study were to provide information on customers for cosmetic companies to develop goods and promotion strategy by examining facial images of university women and their recognition level about cosmetics brand personality. The results were as follows; First, satisfaction level of university women with their lips and eyes was very high, while lowest in skins. Second, factors of brand personality of three kinds of foreign cosmetics brands and three kinds of domestic brands were sincerity, beauty, renovation, reliability and ruggedness. In beauty, reliability and ruggedness, they preferred foreign brands to domestic ones, while they preferred domestic ones in sincerity and renovation. Third, the satisfaction level with face had a statistically significant relationship to the importance of face and cosmetic brands, while the importance of face had to the beauty of the brand. In the interrelationship among facial images and the factors of brand personality, they had significant interrelationships, provided beauty and ruggedness, and reliability and ruggedness had no significant interrelationship.