• 한국산학기술학회논문지
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• 제20권10호
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• pp.149-158
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• 2019

본 논문에서는 다수의 구성품으로 구성된 시스템에 대해 Hidden Failure를 고려하여 최적의 계획 정비 스케줄링 문제에 대해 연구하였다. 계획 정비 스케줄링의 목적은 장기 운용 유지비용 최소화이다. 시스템 측면에서는 다수의 구성품을 그룹화하여 검사함으로써 시스템이 정지함으로 인해 발생할 수 있는 비용을 최소화 할 수 있다. 또한 각 구성품 별로 적절한 검사 주기를 선정하여 고장을 조기에 확인함으로써 고장 발생으로 인한 비용을 최소화 할 수 있다. 본 논문에서는 계산의 복잡성을 줄이기 위해 기존 연구에서 사용한 "Base interval approach"를 적용하였으며 추가적으로 다수 구성품의 동시 검사를 통한 검사비용 절감 효과를 고려하였다. 검사비용은 소요되는 시설, 장비 및 인력 비용으로 구성된다고 가정하였으며 유사한 구성품을 동시에 검사함으로써 검사비용이 절감되는 경우에 대한 분석을 실시하였다. 본 논문에서는 검사비용 절감 효과를 비교하기 위해 기존 연구에서 활용한 사례를 대상으로 분석을 실시하였고 이에 따른 비용 절감 효과를 시뮬레이션을 통해 비교하여 제시한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1582-1590
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• 2011

An analysis of the railroad industry for R&D investments has been insufficient whereas there are lots of analysis of accumulation of technology, economic performances and ripple effects for macroscopic view and other industry of R&D investments. This study decided intellectual rights, patent, and paper as common indicators of scientific and technological performances for setting up performance targets through surveying and analysis of preceding study and verified a appropriateness of scientific and technological performances for railroad R&D 11 projects which were successfully finished. Preceding study has been set up performance targets by research investments as input, but this study made a performance target by model through a cross-sectional and residual analysis of performances of railroad R&D 11 Projects in applying research investments, capital investments, inner labor cost and inner labor cost per man and research time as inputs, and verified a validity and a empirical analysis through analysis of other project.

• 대한산업공학회지
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• 제37권4호
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• pp.390-399
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• 2011

Generally the life-cycle cost of complex systems composed of several sub systems or equipments such as train, aircraft weapon systems is spent much more during operation and maintenance phase than development phase. The maintenance cost for maintaining the availability and extending the life span of systems comprise a large proportion of systems operation cost. The cycle of preventive maintenance affects operation and maintenance cost a lot. In this study we introduce a way minimizing life-cycle cost of systems by calculating more reliable preventive maintenance period than the results of previous study using systems reliability data considered the reliability and failure effect ratio of sub-systems or components. We can solve the preventive maintenance period problem known as NP-Hard as quick as possible by using modified genetic algorithm than using other models introduced in previous study.

• Carbon letters
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• 제16권3호
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• pp.147-170
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• 2015

In recent decades, there has been an increasing interest in the use of carbon fiber reinforced plastic (CFRP) in aerospace, renewable energy and other industries, due to its low weight and relatively good mechanical properties compared with traditional metals. However, due to the high cost of petroleum-based precursors and their associated processing costs, CF remains a specialty product and as such has been limited to use in high-end aerospace, sporting goods, automotive, and specialist industrial applications. The high cost of CF is a problem in various applications and the use of CFRP has been impeded by the high cost of CF in various applications. This paper presents an overview of research related to the fabrication of low cost CF using polyethylene (PE) control technology, and identifies areas requiring additional research and development. It critically reviews the results of cross-linked PE control technology studies, and the development of promising control technologies, including acid, peroxide, radiation and silane cross-linking methods.

• 시스템엔지니어링학술지
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• 제5권1호
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• pp.7-20
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• 2009

This paper describes a case study on the R&D programs of fighter and attacker aircraft such as F-22A, F/A-18E/F, and T/A-50. F-22A and F/A-18E/F were developed in same age. The performance of each program was, however extremely different. F-22A program results in a lot of cost overrun and schedule delay. On the other hand F/A-18E/F program met the cost, schedule, and performance goals. In the T/A-50 program with a super-sonic advanced trainer, T-50 was also developed successfully on planned cost and time by Korea Air-force and KAI. This paper derives key elements for the success of the military aircraft R&D program through lessons learned from th e case study. Each program is analyzed in terms of its background, planning and management.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 1999년도 1st Korea-Japan Advanced Semiconductor Packaging Technology Seminar
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• pp.163-193
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• 1999

• 한국국방경영분석학회지
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• 제36권1호
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• pp.29-38
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• 2010

In Korea weapon system acquisition processes, it's required a cost estimation report obtained from a commercial cost model. The PRICE model is generally used as a cost estimation model in Korea. However, the model uses American historical R&D data and it's output cost component is different from our cost component of defense accounting system. Also, we found that estimating results show about 10% of difference when we comparing with actual costs in 44 finished weapon acquisition projects. There are some limitations in calibration to increase an accuracy of the PRICE model because it's difficult obtain good real input data, detailed cost and technical data in low level WBS. So, only 8% of the defense R&D projects are calibrated and validation of calibration results is more difficult. Therefore, we studied the standard calibration process and performed the calibration about the MCPLXS/E parameters of the PRICE model based on actual cost data. In order to obtain a good calculation result, we collected the actual material costs from the defense industry companies. Our results can be used for an reference in similar weapon system R&D and production cost estimation cases.

• 에너지공학
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• 제6권2호
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• pp.145-151
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• 1997

전력산업의 연구개발투자는 국가경제에 미치는 영향뿐만 아니라 사회후생극대화측면에서도 그 영향은 상당히 크다. 이러한 연구개발투자가 얼마나 효율적으로 이루어져왔나를 분석하여 볼 필요가 있다. 따라서 규제하에서의 독점기업의 적정 연구개발투자규모는 연구개발탄력성과 가격탄력성의 비율로서 결정된다는 것을 수식으로 도출하여 전력산업의 연구개발투자의 효율성유무를 검증하였다. 그 결과 비용이 증가하면 전력판매랑은 증가하여 규모의 경제가 없는 것으로 나타났으며, 규모의 경제를 증가시키기 위해 투자되는 연구개발투자의 정도를 나타내는 연구개발투자집약도는 가격-비용 마진에 부의 효과를 나타내어 현재 전력산업은 연구개발투자가 비효율적으로 이루어지고 있음을 알 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1466-1469
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• 2005

We report effects of electrical aging on the emission stability of carbon nanotube (CNT) paste for low cost and high low-cost and large area field emission devices or displays. Photosensitive carbon nanotube paste was formulated by using of spin on glass (SOG) as an inorganic binder and investigated emission properties and stability depending on electrical aging condition.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1998년도 제13회 하계학술발표회 논문집
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• pp.38-56
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• 1998

We are faced with the crisis of the R&D investment because of the effects of the IMF conditions. Most of the laboratories are going to restructure by the cutting off of money, man power and the reduction of R&D thema. Therefore it is necessary to allocate the R&D resources effectively to the R&D projects. The evaluation and the selection of the R&D projects have been recognized as the most important process for the allocation of the R&D resources. The result of the KITA(1997) shows that the commercial success rate of the R&D from new-product brain storming is only 5.8%. This study aims to analyze the actual conditions of the cost benefit analysis(CBA) of R&D projects of selected laboratories and to study measure methods of the R&D benefits. The research method of this study reviews the CBA of R&D firstly, and surveys 200 selected high ranking labs of the R&D expenditures. For the comparison of the results between '87 and '97, this survey used the same questionaries for each year. As the result of the survey only 27 labs(response rate 13.5%) responded. The result of the '97 survey is as follows : The CBA is used by 44% of responding labs. The economic evaluation method for the R&D project selection is used by 48% of labs and this numbers increased by over 10 percents points compared with the result of '87. The CBA is used for about 40% about each of the budget preparing and the budget analysis, and by 30% of labs to analyze sales and expenditures of the overall period of the project. As the measurement of benefits of R&D projects, 30% of labs responded that it is impossible to measure the benefits, and 20% of labs measured the benefits between sales and expenditures of the R&D project.