• 헤리티지:역사와 과학
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• 제51권3호
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• pp.88-103
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• 2018

본 연구는 지속가능성을 고려한 명승의 종합정비계획 요소를 발굴하고 필요성을 분석하는 것을 목적으로 하였다. 이에 따라 명승의 지정이 확대되기 시작한 2006년부터 2017년 사이에 수립된 35건의 종합정비계획 보고서를 토대로 '조사 분야'와 '계획 분야'에 사용된 항목을 검토하여 전국 60개 지자체의 명승 실무 담당자를 대상으로 "리커트 5점 척도"로 필요성에 대한 설문을 실시하였다. 전국 60개 지자체로부터 회수된 45개 설문지에 대한 실무 담당자 48명의 의견을 분석하였다. 응답에 대한 일관성을 검증하기 위해 "신뢰도 분석(Reliability Analysis)"를 수행하였으며 크론바흐 알파계수(Cronbach's Alpha)가 조사 분야에서 0.968, 계획 분야에서 0.970으로 나타나 높은 신뢰성을 보였다. 설문조사결과, 종합정비계획의 6개 조사 분야에 대한 항목의 필요도에서도 전반적으로 필요하다는 의견이 다수를 이루었다. 특히, '역사환경'과 '자연환경', '인문환경', '경관'에 대한 조사의 필요성이 높게 평가되었다. 또한 '일반환경'과 '이용자'부문에서도 주요 문화재 및 유적의 분포(4.04), 지역주민 및 이해관계자의 의견 수렴(4.15) 등 특정 항목에 대한 필요성도 보통 이상으로 나타났다. 한편, 계획 분야에 대한 항목의 필요성에서도 대체적으로 필요(4.0)의 수준으로 평가 결과가 나타났다. 그 중에서도 '역사환경'의 지정가치 및 위상강화(4.26), 문화재 지정구역 및 역사문화환경보존지역의 정비계획(4.25), 그리고 '인문환경'의 명승 내 역사적 건축물에 대한 수리(4.28), '경관'부문의 경관탐방로계획(4.28)에 대한 항목들은 필요도가 높았다. 이처럼 명승의 종합정비계획 수립에 필요한 것으로 확인된 조사와 계획 항목들은 새로 마련된 "명승 종합정비계획 수립 및 시행에 관한 지침"과 함께 종합적 차원에서 명승의 효율적인 보존과 관리에 기여할 수 있을 것으로 기대된다.

• 산업경영시스템학회지
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• 제42권4호
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• pp.145-152
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• 2019

All machines deteriorate in performance over time. The phenomenon that causes such performance degradation is called deterioration. Due to the deterioration, the process mean of the machine shifts, process variance increases due to the expansion of separate interval, and the failure rate of the machine increases. The maintenance model is a matter of determining the timing of preventive maintenance that minimizes the total cost per wear between the relation to the increasing production cost and the decreasing maintenance cost. The essential requirement of this model is that the preventive maintenance cost is less than the failure maintenance cost. In the process mean shift model, determining the resetting timing due to increasing production costs is the same as the maintenance model. In determining the timing of machine adjustments, there are two differences between the models. First, the process mean shift model excludes failure from the model. This model is limited to the period during the operation of the machine. Second, in the maintenance model, the production cost is set as a general function of the operating time. But in the process mean shift model, the production cost is set as a probability functions associated with the product. In the production system, the maintenance cost of the equipment and the production cost due to the non-confirming items and the quality loss cost are always occurring simultaneously. So it is reasonable that the failure and process mean shift should be dealt with at the same time in determining the maintenance time. This study proposes a model that integrates both of them. In order to reflect the actual production system more accurately, this integrated model includes the items of process variance function and the loss function according to wear level.

• Journal of Advanced Marine Engineering and Technology
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• 제24권2호
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• pp.90-96
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• 2000

The technology of preventive maintenance and corrective maintenance is widely applied to ships in order to maintain the good voyageable condition. One of the most important fields of marine engineering is to seek the maximum availability and to solve the stochastic maintenance problem such that the cost for corrective maintenance is minimized. Accordingly, for the purpose of making the most suitable maintenance schedule which minimizes the expected cost function, this paper suggests the method to grasp the failure characteristics by the ship's maintenance data that are collected from the past. And, suggests the method to estimate the optimal maintenance interval by using the dynamic programming and the cumulative hazard rate function attained from the maintenance data.

• 산업경영시스템학회지
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• 제15권26호
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• pp.173-179
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• 1992

This paper is concerned with preventive maintenance model for the items whose failures are dependent on their wear level. The previous maintenance models have used time as their decision variable, but it is not appropriate for the case which have wear dependent processes for their failures. In this paper, we consider an operating item which is under periodic review and which is subject to degradation. The scheduled maintenance (overhaul ) is based on the level of item degradation rather time. A functional equation for the total expected cost over an infinite horizon period is formulated and solved.

• 인간식물환경학회지
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• 제23권3호
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• pp.347-362
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• 2020

Background and objective: It is difficult to conclusively determine the exact cause of tree defects since multiple causes are involved such as climate change, plantation, tree quality and planting time, construction, planting base, drainage, sunshine conditions, maintenance, and microclimate. The data related to landscaping construction defects are scattered or fragmented by companies and years, but not managed systematically by the defect information management system. Most of the earlier studies associated with tree defects in apartment complexes suggested defect rates after examining tree defects in the completed construction site and proposed fragmentary and subjective conclusions about the causes of defects observed in trees with high defect rates. It is proposed to continue to conduct studies on the establishment and analysis of systematic databases to identify the exact causes of tree defects and measures to improve, and the need to accumulate systematic data in the construction process where many defects arises. This study was conducted to reduce the defects of trees planted in apartment complexes. Methods: Main factors related to tree defects were subdivided based on the results of literature review and a defect investigation at the completion site, and tree history management items were selected and subdivided during the construction stage. Results: The criteria for the preparation of subdivided items were obtained, and the tree history management checklist was written for the site under actual construction and a systematic database was established. Items that are categorized based to the causes of defects include the location of nurseries, date, tree quality, site conditions, planting techniques, microclimates, and maintenance. Conclusion: This study suggested tree history management items based on the tree defects that can be identified at the construction stage and applied them to the selected study site, which differentiates this study from earlier studies. It will be necessary to conduct a comprehensive and objective time series analysis on tree defects that occur over time by continuously monitoring and collecting data after construction.

• 산업경영시스템학회지
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• 제29권3호
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• pp.135-142
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• 2006

Engineers are always concerned with life cycle costs for making important economic decisions through engineering action like reliability of products. Decisions during the reliability growth development of products involve trade-offs between invested costs and its returns. In order to find minimal LCC containing the reliability improvement cost, production cost, repair and replacement costs, and holding cost of spare parts for failure items we suggest in this paper relationship between development cost and sustaining cost in values of growth parameter $\beta$ of AMSAA model. This model is applied to the reliability growth program based on AMSAA model during R&D phase, the warranty activities of items and the block replacement policy for maintenance of items in avionic equipment.

• 융합정보논문지
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• 제11권3호
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• pp.125-131
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• 2021

모든 장비는 지속적인 사용에 의해 공정의 생산성과 경제성은 감소한다. 그러므로 일정 시점에서는 공정평균이동 문제라는 설비에 대한 예방보전이 필요하다. 설비의 보전시기를 결정함에 있어, 우리는 기존 연구에서 부분적으로 진행되어 온 보전모형들을 확장하고 통합함으로써 다양한 상황이 발생하는 생산 현장을 반영한 보전모형을 제시하고자 한다. 이를 구현하기 위해 제품규격은 상하한의 양쪽을 설정했으며, 적합품에 대해 품질손실함수를 도입했다. 마모수준에 대한 공정분산은 상수가 아닌 함수로 설정했으며, 특히 제품생산량과 보전비용에 있어서는 마모수준에 대한 함수를 개발하여 적용했다. 이로써 본 연구는 현장의 다양한 공정에 대부분 적용할 수 있는 보전모형이 될 것으로 생각한다. 추후 연구에서는 보전모형을 구성하는 부적합비용, 품질손실비용, 보전비용에 더하여 제품판매로 인한 수익 항목을 추가한 전체 수익 최대화 문제로 전개할 수 있을 것이며, 크게는 본 연구의 모형에 고장률을 도입한 보전모형으로의 확장도 생각해 볼 수 있을 것이다.

• 한국농촌건축학회논문집
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• 제20권2호
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• pp.1-9
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• 2018

The purpose of this study was to develop guidelines for sustainability of back-to-farm community village in 4 aspects; social environment, maintenance and management, regional environment, and economic environment. These 4 aspects, which count for sustainability, based on the comprehensive comparative analysis about items that field survey and literature suggested. Conclusions of guideline are of the following. The guidelines on social environment are developed by 3 items; resident participation and activity, village leader, decision making in village and person in charge of operation. The guidelines on maintenance and management are developed by 5 items; village operation system, village regulation, transparency of management, village operation expenses, and management type. The guidelines on regional environment are developed by 2 items; support by central and local government, and area projects and connection to regional resources. The guideline on economic environment is not developed due to low demands of based production facilities and income increase facilities.

• 한국CDE학회논문집
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• 제20권3호
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• pp.281-290
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• 2015

The specific goal of the SMS (Ship Management System) is to increate ship safety and decrease maintenance fee. Equipment of ship is managed by PMS (Planned Management System), subsystem of SMS. But hull has not managed by ship manager. So, the Classes have developed the system for hull maintenance. Recently, the ship maintenance system has been developed for satisfying operator's requirements such as managing maintenance data as integrated platform, intuitive manipulation and design for ease of use. To reflect such requirement, 3D Model based maintenance system was introduced for ship in operation stage. Hull items that have to be inspected, repaired, replaced, are stored in integrated data platform with drawing, reports, and etc. and completely linked to 3D product Model. This system is specially developed for measurement and maintenance of hull thickness.

• 한국재난정보학회 논문집
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• 제16권1호
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• pp.10-20
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• 2020

연구목적: 터널구조물 유지관리계측의 현장점검 결과를 분석하여 개선방안을 제시한다. 연구방법: 도심지에서 건설되고 있는 서울지하철◯호선 14개 공구의 터널구조물을 대상으로 유지관리계측에 대한 다양한 항목의 문제점을 조사하고 분석을 실시하였다. 연구결과: 유지관리 계측 항목과 계측수량 및 설치위치는 개착터널과 굴착터널로 구분하여 개선방안을 제시하였다. 계측기기의 내구연한은 각종 기준을 검토하였고, 내구성 확인방법은 계측센서의 승인 및 검수, 검사 및 시험, 검정 및 교정 등의 개선방안을 제시하였다. 결론: 터널구조물 유지관리계측의 개선방안을 건설현장에 적용하면 유지관리계측의 효율성이 증대되고 건설계측 기술발전에 기여할 것이다.