• 한국기계가공학회지
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• 제20권4호
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• pp.119-126
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• 2021

During the development of a weapon system, the concept of maintainability is used for quantitatively predicting and analyzing the maintenance time. However, owing to the complexity of a weapon system, the standard maintenance time predicted during the system's development differs significantly from the measured time during the operation of the equipment after the system's development. According to the analysis presented in this paper, the maintenance time can be predicted by considering the system's complexity on the basis of the military specifications, and the procedure can be Part B of Procedure II and Method B of Procedure V. The maintenance work elements affected by the system complexity were identified by the analytic hierarchy process technique, and the system-complexity-reflecting weights of the maintenance work elements were calculated by the Delphi method, which involves expert surveys. Based on MIL-HDBK-470A and MIL-HDBK-472, it is going to present a Korean-style maintainability prediction method that reflects system complexity of weapons systems.

• 한국건설관리학회논문집
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• 제22권1호
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• pp.72-80
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• 2021

지난해 기준 국내 30년이 넘은 노후화 건축물이 37%를 차지하고 있으며, 건물 노후화 수치가 점차적으로 늘어남에 따라, 건물유지보수의 필요성이 대두되고 있다. 건물의 유지보수를 위해서는 많은 작업 주체가 참여하여 업무를 진행한다. 그 중 '유지보수 관리자'의 업무가 가장 큰 비중을 차지한다. 현재 업무를 살펴보면 유지보수 건축물의 이력관리를 도면 혹은 수기로 기록하여 보관하는 방식으로 진행되고 있으며, 해당 자료를 재 열람하기 위해서는 많은 시간이 소모된다. 이에 본 연구에서는 작업자의 유지관리 업무 편의성 향상과 이력관리를 최적화 하기위해 기존 유지보수 프로세스를 파악하고, 분석하여 문제점을 도출하고 스마트 디바이스 기반의 자동화 모델을 구축하였다. 본 연구는 스마트 디바이스 기반의 자동화 모델 구축을 위하여, ① 일반적인 시설물 관리 프로세스 분석 및 관련 문헌 검토, ② 현재 유지보수 프로세스 개선, ③BIM Data, COBie Data, IoT 및 AR 기술을 기반으로 유지보수 관리 자동화 모델 기능 구성도 제작, ④ 스마트 디바이스 기반 유지보수 관리 자동화 모델 구축, ⑤ 사례 현장 적용, 유지보수 관리 진행 및 이력정보 재검토 소요 시간 비교를 통한 시스템 검증을 실시하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.960-968
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• 2005

The high cost in maintaining complex manufacturing process makes it necessary to enhance an efficient maintenance system. For the effective maintenance of manufacturing process, precise fault diagnosis should be performed and an appropriate maintenance action should be executed. This paper suggests an intelligent fault diagnosis system using hybrid data mining. In this system, the rules for the fault diagnosis are generated by hybrid decision tree/genetic algorithm and the most effective maintenance action is selected by decision network and AHP. To verify the proposed intelligent fault diagnosis system, we compared the accuracy of the hybrid decision tree/genetic algorithm with one of the general decision tree learning algorithm(C4.5) by data collected from a coil-spring manufacturing process.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.280-283
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• 2015

Many construction projects have used the building information modeling (BIM) extensively considering data interoperability throughout the projects' lifecycles. However, the current approach, which is to collect the data required to support facility maintenance system (FMS) has a significant shortcoming in that there are various individual pieces of information to represent the performance of the facility and the condition of each of the elements of the facility. Since a heterogeneous external database could be used to manage a construction project, all of the conditions related to the building cannot be included in an integrated BIM-based building model for data exchange. In this paper, we proposed an ontology-based facility maintenance information model to integrate multiple, related pieces of information on the construction project using industry foundation classesbased (IFC-based) BIM data. The proposed process will enable the engineers who are responsible for facility management to use a BIM-based model directly in the FMS-based work process without having to do additional data input. The proposed process can help ensure that the management of FMS information is more accurate and reliable.

• 전기학회논문지
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• 제57권5호
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• pp.735-740
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• 2008

Recently, the research of PM (Preventive Maintenance) method on the RCM(Reliability-Centered Maintenance) of the system equipment is being actively advanced for a few years. For the most of the current power equipment maintenance, the state of the equipment after maintenance is assumed to be becoming 'as good as new ones' state. However, the state of the power equipment is maintained like the states of the between 'as good as new ones' and 'as bad as old ones' by imperfect maintenance that implies the life decrease of the equipment by frequent breakdown, the error of maintenance process, and so on. So, the Maintenance method considering the real case has to reflect Imperfect maintenance than perfect maintenance. This paper suggests the Preventive Maintenance method by using Quasi - Renewal Theory for the gas turbine equipment as deliberating the imperfect maintenance for the real cases.

• 산업경영시스템학회지
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• 제41권1호
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• pp.110-117
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• 2018

Machines and facilities are physically or chemically degenerated by continuous usage. One of the results of this degeneration is the process mean shift. By the result of degeneration, non-conforming products and malfunction of machine occur. Therefore a periodic preventive resetting the process is necessary. This type of preventive action is called 'preventive maintenance policy.' Preventive maintenance presupposes that the preventive (resetting the process) cost is smaller than the cost of failure caused by the malfunction of machine. The process mean shift problem is a field of preventive maintenance. This field deals the interrelationship between the quality cost and the process resetting cost before machine breaks down. Quality cost is the sum of the non-conforming item cost and quality loss cost. Quality loss cost is due to the deviation between the quality characteristics from the target value. Under the process mean shift, the quality cost is increasing continuously whereas the process resetting cost is constant value. The objective function is total costs per unit wear, the decision variables are the wear limit (resetting period) and the initial process mean. Comparing the previous studies, we set the process variance as an increasing concave function and set the quality loss function as Cpm+ simultaneously. In the Cpm+, loss function has different cost coefficients according to the direction of the quality characteristics from target value. A numerical example is presented.

• 품질경영학회지
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• 제43권4호
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• pp.499-510
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• 2015

Purpose: This paper treats the improvement of the quality and reliability of military weapon systems based on the maintenance data. Methods: The proposed method of the data integration and refinement are used to obtain the component reliability information and to find the frequently failed components based on the Pareto analysis. Based on the reliability information and the number of failed component frequencies, the target components of quality improvement are determined and improved by multiple methods such as engineering changes, special meetings, additional training and revising maintenance manuals. Results: Based on the proposed process, we find some components which need to be improved in order to enhance the quality and reliability. Conclusion: A process is developed for improving the quality and reliability of weapon systems. This process will be adopted by various weapon systems to enhance the quality and reliability, as well as reduce military spending.

• 한국경영과학회지
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• 제6권2호
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• pp.7-11
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• 1981

An inspection-maintenance policy is investigated for a system having various states. A policy is characterized by the type of maintenance and the next inspection time. Maintenance actions are classified into various types according to the depth of maintenance. Policy evaluation criterion is the expected cost accumulated up to the failure of the system. The problem is formulated as a Markov decision process and an optimal policy is found by using a policy improvement procedure. A numerical example illustrates the policy for a system having five states.

• 품질경영학회지
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• 제25권1호
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• pp.31-43
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• 1997

In this study, the pros and cons of TPM and RCM were comparatively evaluated at various aspects : a, pp.ication process, objectives, maintenance items, organizations, analysis of maintenace methods, etc. It is found that TPM can be considered as a management discipline. However, in TPM, there seldom exist concrete rules or guidelines to select a maintenance scheme. RCM, which is a widely used maintenance scheme for aircrafts or power plants, has a good analysis and decision logic for maintenance planning. In the paper, similar decision rules are adopted to TPM deployment to get an effective and effecient maintenance Planning.

• 한국건축시공학회지
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• 제10권5호
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• pp.55-67
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• 2010

본 논문은 임대아파트의 유지관리 프로세스 및 데이터 모델을 제시하였다. TO-BE 모델은 프로세스, 취해질 활동, 어떤 정보가 활동 사이에서 어떻게 교류되어야 하는가 하는 방법을 표준화 하는데 기여하며 IDEF0 모델의 형태로 제시되었다. 데이터 모델은 TO-BE 모델에서 추출한 유지관리시스템 프로세스를 근간으로 DB 구축을 위한 ERD를 제시하였다. 유지관리 분야 연구 성과로서 임대아파트의 유지관리 업무에 대한 구조적이고 그에 대한 기준을 설명할 수 있는 프로세스 모델이 개발되었다. 또한 본 모델은 유지관리에 참여하는 조직 내에서 정책의 결정을 위한 가이드라인으로 작용할 수 있다. TO-BE 모델은 수명 주기 동안 임대자산에 투자되는 자본을 유지하고, 기능을 향상시키기 위해 실행되는 효과적인 전략과 절차(개념적 모델을 통한 데이터와 지식의 통합)와 별도로 유지관리 관행 전반에 관한 방법을 규정할 수 있게 해 주는 기초자료가 될 것이다. 구현된 애플리케이션은 프로세스 모델을 근간으로 설계된 데이터 모델에 대한 활용을 보여준다.