• Industrial Engineering and Management Systems
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• 제6권1호
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• pp.22-27
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• 2007

This paper describes the optimization of maintenance workforce scheduling at Afam power station in Nigeria. The objective is to determine the optimum schedule to satisfy growing maintenance labour requirements with minimum cost and highest efficiency. Three alternative maintenance workforce schedules are compared. The first alternative is to continue with the traditional five-day workweek schedule currently being practiced by Afam power station maintenance line. The second alternative is to switch to a seven-day workweek schedule for the morning shift only. The third alternative is to use a seven-day workweek schedule for all three work shifts. The third alternative is chosen, as it is expected to save 11% of the maintenance labour cost.

• 한국산업융합학회 논문집
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• 제24권6_2호
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• pp.861-872
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• 2021

An efficient cost management is important for the domestic social overhead capital(SOC) based on a long lifecycle after 30 years since completion. Maintenance in South Korea have had the restrictions of consistency and suitability of decision-making by the establishment of a budget plan based on the company estimate and repair and reinforcement methods determined by the inspection and diagnosis engineers' subjective determination for each facility. To resolve this issue, the Korea Institute of Civil Engineering and Building Technology is currently in development of a methodology to propose an optimum maintenance method according to the damage of components by artificial intelligence. This study has deduced the primary factors by analyzing information generated during bridge maintenance and management as a prior step for the development of technologies, and conducted a preliminary analysis to select the optimum artificial intelligence technology.

• 한국건설관리학회논문집
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• 제2권4호
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• pp.135-143
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• 2001

본 연구는 오피스건축물의 최적경제수명을 Life Cycle Cost를 고려하여 추정분석하고, 이를 통해 최적경제수명 이후의 건축물을 어떻게 관리하는 것이 경제적으로 유리한가에 대한 것이다. 경제수명의 추정에서 초기투자비와 유지관리비를 중요한 요소로 고려하여, 여의도$\cdot$마포지역의 오피스건물을 대상으로 조사한 내용을 단위면적 당 동일한 가치로 환산한 뒤, LCC를 이용하여 최적경제수명을 추정하였다. 마지막으로 최적경제수명 이후의 관리방법으로 재건축 및 보수공사 시 투입되는 금액에 따라 5개의 안으로 비교하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제8권3호
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• pp.131-140
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• 2004

본 연구의 목적은 재료 및 기하학적 비선형을 고려한 개선된 소성힌지 해석을 이용한 평면 강골조 시스템의 최적설계알고리즘 개발이다. 개발된 알고리즘을 이용하여 기둥의 유효길이계수(K-factor) 산정없이 골조의 최적설계를 수행하였다. 본 연구에서 2개의 파리미터를 이용한 다단계 이산화 최적화기법이 개발되어 적용되었다. 목적함수는 구조물의 중량을, 제약조건은 임계하중, 사용성, 유연성등이 고려되었다. 예제를 통해 개발된 프로그램의 효율성, 적용성, 유용성등을 보였다.

• 한국구조물진단유지관리공학회 논문집
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• 제12권6호
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• pp.241-248
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• 2008

민감도 해석은 구조 모델링 변수의 변화에 따른 역학적인 거동의 특성을 찾는 것을 목적으로 한다. 따라서 건물의 구조 진단과 보수 보강 분야에서 특히 중요한 설계 자료로서 활용되고 있다. 본 연구는 구조물의 위상학적 최적 모델링에서 중요하게 다루어지는 민감도 해석을 다양한 방법을 사용하여 공식화하였다. 감차법과 변분법을 적용하여 직접법과 수반법으로서 최종적인 해석적인 민감도 식들을 유도하였다. 구조 해석에 관한 간단한 수치예제를 통하여 유도된 민감도 식들의 해가 적절함을 수치적인 민감도 해석치와 비교하여 검증하였고, 최종적으로 이산화 민감도 해석에 의한 밀도분배법의 위상학적 최적 모델링을 수행하여 민감도 공식들을 위상 최적화 문제에서 정식화하였다.

• 대한조선학회논문집
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• 제47권2호
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• pp.258-264
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• 2010

Various kinds of ballast water treatment systems (BWTS) have been developed corresponding to reinforced IMO rules for marine environment. Some of them got the certificate of IMO and others are waiting for it. Selection of optimum BWTS is very important. Optimum BWTS means not only functional requirements but also economic efficiency. This paper presents economic analysis model for optimum BWTS according to ship type and size. In this study 10 kinds of BWTS whose initial installation cost and maintenance cost are known are analyzed based on present worth method. It is assumed that all BWTS satisfy minimum functional requirements and we need to consider different economical efficiency. Through the economic analysis we could select optimum BWTS.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.886-891
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• 2004

The process of determining whether, when, where and how to intervene, of deciding on optimum allocation of resources and minimizing the cost is a very complex problem: different track sections tend to behave differently under the effects of loading; decision-making processes for maintenance work are closely interrelated technically and economically; decision-making for maintenance plans is based on a large quantity of technical and economic information, extensive knowledge and above all experience. For that reason, It is considered very important to develope objective and computer-aided decision-making support system for track maintenance plan. On this paper, we made a survey of the state-of-art of decision-making support systems for track maintenance which were developed and used abroad and reviewed requirements of system and present the plan of develope decision-making support system for track maintenance appropriate to local condition.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.235-236
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• 2010

Since many structures in the sea environment are damaged by chloride, appropriate repair strategy is required. Therefore in the paper, optimum period for the RC structure's repair is calculated with consideration of economic efficiency. Moreover, when the concrete members are repaired with the other material such as polymer mortar forr section restoration, their expected service life also calculated to predict more accurate repair period during the life span.

• 한국압력기기공학회 논문집
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• 제7권2호
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• pp.7-13
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• 2011

Turbine journal bearings are designed to support the weight of the rotors on a hydrodynamic oil film and to provide dynamic stability to the rotor system. The life time of journal bearings is infinite theoretically because the journal bearings are separated from the shaft journal by oil film. But poor design, assembly, operation and maintenance can cause problems to the journal bearings. The FMEA(Failure Mode and Effects Analysis) results of the journal bearings show that frequent maintenance of the journal bearings can cause failures and reduction of the bearing life. Therefore, the maintenance periods and history of the journal bearings with the bearing FMEA results are reviewed in order to establish the optimized maintenance period of the journal bearing for the nuclear power plants. Consequently it is necessary to maintain a best condition of lubrication system, reject time-based maintenance and perform the condition-based maintenance of journal bearings in order to maintain optimum condition of the journal bearing.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(II)
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• pp.454-459
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• 2003

The process of determining whether, when, where and how to intervene, of deciding on optimum allocation of resources and minimizing the cost is a very complex problem: different track sections tend to behave differently under the effects of loading; decision-making processes for maintenance work are closely interrelated technically and economically; decision-making for maintenance plans is based on a large quantity of technical and economic information, extensive knowledge and above all experience. For that reason, It is considered very important to develope objective and computer-aided decision-making support system for track maintenance plan. On this paper, we reviewed ECOTRACK system and present the plan of develope decision-making support system for track maintenance appropriate to local condition.