• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.224-230
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• 2015

항공기 엔진 체계의 신뢰성과 안전성을 분석하는 것은 RAM 분석이라고 한다. RAM은 제작자가 개발한 시스템의 지속가능성 혹은 그 체계의 수명주기비용(Lice Cycle Cost)에 중대한 영향을 줄 수 있는 시스템 설계특성을 의미한다. 또한 RAM은 시스템이 개발될 당시에 의도된 임무를 수행할 수 있는 능력 혹은 임수수행을 성공할 수 있도록 담보하는 중요한 역할을 한다. RAM은 1970년대 이후 미국 군수분야에서는 군수지원성분석(LSA, Logistic Support Analysis) 과 밀접히 연계되어 활용되어 왔으며, RAM과 LSA를 통합하여 종합군수지원체계(ILS, Integrated Logistics Support)라고 부른다. 본 연구에서는 항공기 엔진에 대한 신뢰성 분석에 Weibull 분포를 활용하였다. Weibull 분포는 2개의 변수 적용에서 다음과 같이 정의된다. 변수가 그 계의 어떤 값을 나타내느냐에 따라 분포도 곡선의 특성 의미는 변수에 의존된다. 예를 들어 시험성적, 사회적 특성을 표현하는 인지도, 산업 제품의 고장이나 결함을 나타내는 고장관련 모수(변수) 등에 따라 그 특징을 나타내게 된다. 항공기 엔진의 신뢰성 분석을 통해 항공기 엔진의 수명 판단이 가능해졌으며 임무 불가능 수준의 In-Flight Shut-Down 비율이 현격히 감소됨을 확인할 수 있었다.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.4
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• pp.617-624
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• 2020

Due to the rapid development of science technology and the main characteristics of the defense industry, such as long development period, design complexity, high possibility of discontinuing parts due to long life cycle, and small quantity production, it can cause increasing of the inflow possibility of counterfeit electronic parts and deteriorating the reliability of weapons systems. This paper presents the specific criteria for the identification of electronic parts to be verified for mass produced weapons systems after the development is completed, and the identification and verification methods for the inflow of counterfeit electronic components.

• Proceedings of the Korean Reliability Society Conference
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• 2000.11a
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• pp.321-328
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• 2000

본 연구는 새로운 장비체계 도입 시 초기 일정기간 동안 장비의 목표가용도 유지를 위해 필요한 동시조달수리부속(Concurrent Spare Parts)와 적정소요 산출에 관한 해법을 제시한다. 새로운 장비체계 도입 시 함께 보급되는 예비수리부속은 장비체계 운용에 중요한 역할을 한다. 따라서 장비체계가 주어진 임무를 수행하는 동시에 정상상태를 유지하기 위한 적정수준의 예비부속 확보가 필요하며 최소의 비용으로 장비의 가동률을 극대화 할 수 있도록 하여야 한다. 본 연구에서는 부품의 고장특성 및 수리능력을 고려한 고장분포함수를 바탕으로 각 부속별 중요도를 만족시키는 초기 수리부속 소요 결정모형과 해 산정기법을 제시하며 가용예산 제약에 따른 소요조정을 통해 최적의 예비부속 재고수준을 결정한다.

• Journal of the KSME
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• v.47 no.9
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• pp.47-52
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• 2007

• Journal of the KSME
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• v.49 no.2
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• pp.51-57
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• 2009

• Journal of Gifted/Talented Education
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• v.26 no.2
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• pp.281-297
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• 2016

The purpose of this study was to investigate the structural relationships between gifted preschool children and their related variables(creativity, motivation, family system). 230 preschool children, parents and teachers from U-city have participated in this study. the collected data were analyzed with SPSS and AMOS. The goodness of fit was evaluated using the SRMR, RMSEA, CFI, and TLI. The results of this study were as follows: First, family system(adaptability, cohesion) were found to have a statistically significant direct impact on gifted preschool children. Second, creativity were found to have a significant direct effects on gifted preschool children. moreover they also had an indirect effect on gifted preschool children through family system. Third, motivation were found to have a statistically significant direct impact on gifted preschool children.

• Journal of Applied Reliability
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• v.15 no.1
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• pp.1-5
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• 2015

This note suggests three approaches to improve reliability in developing weapon systems. The high complexity of the weapon systems make it hard to analyze and predict of those reliability. Current situations of the reliability have been reviewed in terms of logistics support analysis (LSA), warranty policy, maintenance and development. Three suggestions are notified to improve the reliability considering the complexity of the weapon systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.10
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• pp.892-897
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• 2017

As the weapon system SW development and management manual of the DAPA, which is the regulation for the overall weapon system SW development, is revised, the level and scope of SW reliability test are upgraded to improve the reliability and quality of SW. It is a big burden for SW developers. In particular, the dynamic test requires a schedule and manpower required to implement the weapon system SW, and should be performed every time the source code changes, not just one time. In this paper, we propose a regression test automation program(VectorCast Environment Manager) that performs a dynamic test using VectorCast, a dynamic test tool, and then performs a regression test automatically by minimizing human intervention in the regression test of dynamic test due to the change of the source code.

• Journal of Korean Society for Quality Management
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• v.9 no.2
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• pp.31-36
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• 1981

This paper deals with the reliability optimization of parallel - in - series system subject to several linear constraints. The model of nonlinear constrained optimization is transformed to a saddle point problem by using Lagrange multipliers. Then Newton - Raphson method is used to solve the resulting problem and these step - by - step solution procedures are programmed in Basic Level II of micro - computer TRS-80. An example which has two linear constraints is solved and the results are analyzed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.289-299
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• 2016

Weapon systems require reliability in the development phase for efficient combat readiness. Improved reliability in various manufacturing processes have been achieved using data analysis. However, data analysis in the development phase is difficult due to problems such as the lack of data, high cost, and the importance of security. Therefore, Post Logistics Support (PLS) data collected following integration is analyzed for long-term quality improvement of weapon systems. In this study, we propose a methodology for examining the correlation between the failure rate and PLS data as follows: First, key variables affecting reliability were identified the correlation between variables on the failure rate examined. Second, corresponding analysis was conducted for determining the correlation between patterns of categorical data. Third, extract categories with the higher contribution and quality of representation, and find the highest variable correlated with failure period through visualization. Then, after selecting patterns which have shorter failure period, the cause of decreased reliability was confirmed through frequency analysis. This study will contribute to improving reliability when developing new weapon systems and will help to strengthen the combat readiness of military.