• 제목/요약/키워드: Maintenance & Repair

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무작위 초 보유 자원을 이용한 신뢰성 모델

  • Kim, Songkyoo
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2001년도 추계학술대회 논문집
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    • pp.199-202
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    • 2001
  • This article deals with stochastic reliability systems that include a repair facility and unreliable machines: the main facility of working and an auxiliary facility of "super-reserve" machines. The number of super-reserve machines are random number with a arbitrarily distribution and working machines break down exponentially. Defective machines line up for repair, whose durations are arbitrarily distributed. Refurbished machines return to the main facility. If the main facility is restored to its original quantity, the repair facility leaves on routine maintenance until all of super-reserve machines are exhausted. Then, the busy period is regenerated. The whole system also falls into the category of closed queues, with more options than those of basic models. The techniques include two-variate Markov and semi-regenerative processes, and a duality principle, to find the probability distribution of the number of intact machines. Explicit formulas obtained demonstrate a relatively effortless use of functionals of the main stochastic characteristics (such as expenses due to repair, maintenance, waiting, and rewards for higher reliability) and optimization of their objective function. Applications include computer networking, human resources, and manufacturing processes.

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A decision support system for diagnosis of distress cause and repair in marine concrete structures

  • Champiri, Masoud Dehghani;Mousavizadegan, S.Hossein;Moodi, Faramarz
    • Computers and Concrete
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    • 제9권2호
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    • pp.99-118
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    • 2012
  • Marine Structures are very costly and need a continuous inspection and maintenance routine. The most effective way to control the structural health is the application of an expert system that can evaluate the importance of any distress on the structure and provide a maintenance program. An extensive literature review, interviews with expert supervisors and a national survey are used to build a decision support system for concrete structures in sea environment. Decision trees are the main rules in this system. The system input is inspection information and the system output is the main cause(s) of distress(es) and the best repair method(s). Economic condition, severity of distress, distress situation, and new technologies and the most repeated classical methods are considered to choose the best repair method. A case study demonstrates the application of the developed decision support system for a type of marine structure.

콘크리트 누수균열의 유지관리를 위한 누수보수용 주입형 실링재 시공방법 연구 (A Study on the Construction Methods of Sealer of Injection Type for Leakage Maintenance for Water Leakage and Cracks in Concrete)

  • 권시원;오미현;곽규성;오상근
    • 한국건축시공학회지
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    • 제6권1호
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    • pp.87-91
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    • 2006
  • Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

공동주택 건물 외부공간 및 옥외시설의 공종별 수선비용 산정모델 (Repair Cost Estimation Model of the Building Exterior and Outdoor Facilities in Apartment Housing)

  • 이강희;채창우
    • KIEAE Journal
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    • 제16권3호
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    • pp.129-135
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    • 2016
  • Purpose: Building figuration is imperative to perceive the its value, environmental clean status and form. Therefore, maintenance activities of the building exterior are required to keep the housing condition and value. Each household should pay the repair cost which is brought out in the future. For this repair cost, the estimation model would needed to forecast and provide the required cost. This study aimed at providing the estimation model of the repair cost, using the repair survey data between the 2011 and 2014 in Seoul. Method: For these, it took various estimation function of repair cost such as 1st function, inverse function and so on. These above functions would be applied into the building exterior and outdoor facilities which figure the building shape and characteristics. Result: Results of this study are shown ; First, among 11 estimation models, the power function has a better statistics and goodness-of-fit than any other models. Second, the estimation model with a variable of household has a pattern in upward to the right. On the contrary, the model with management area is little downward to the right. Both of them are depended on the estimated parameter of the power function and the parameter smaller than 1.

재보수-보강된 철근콘크리트 보-기둥 접합부의 구조특성 (Structural Characteristics of Reinforced Concrete Beam-Column Joints Repaired and Restrengthening)

  • 조창호;김정섭
    • 한국구조물진단유지관리공학회 논문집
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    • 제7권2호
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    • pp.231-238
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    • 2003
  • 지진에 의해 피해를 입은 철근콘크리트 건축물을 재사용이 가능하도록 보수-보강을 실시하여 구조적으로 안전성을 확보하게 되는데 이러한 보수-보강이 부적절하게 시공되었거나, 재지진을 받아 구조내력이 크게 감소된다면 다시 보수-보강을 할 수 밖에 없다. 본 연구에서는 지진 발생시 가장 우려되는 보-기둥 접합부를 실험 대상으로 선정하여, 시험체에 1차 동적하중과 2차 동적하중을 작용시킨 후 각각 보수-보강을 실시한 다음 구조특성 및 하중속도에 따른 보강성능을 검토하여 재보수-보강의 타당성을 규명하였다.

교육시설 내용년한 산정 연구 - 옥상방수와 바닥마감재를 대상으로 - (Establishment of the Service Life of the Education Fcilities - Focused on the Roof water-proof and Floor finishings -)

  • 이강희;채창우
    • 교육시설 논문지
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    • 제24권6호
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    • pp.27-36
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    • 2017
  • Educational facilities have an affect to make a decently learning environment. After constructed, it needs a maintenance plan to keep the performance or function which provide the repair time, repair scope and ratio. But the fundamental data are so insufficient that the field worker can't provide the maintenance plan and has no choice use the other data which concerned with apartment or office building. Above all, the service life is indispensible to make a repair plan because the repair time and scope would be provided within the service life. This study aimed at providing the method to make a service life of component in educational facilities and applying the method into the roof proof and floor finishing. Results are shown that first, it is important to set the $1^{st}$ repair time after constructed. when it proposes the three ways with the probability approach, choice probability model and cumulative cost function. Second, the service life of roof proof is provided with about 35 years. In addition, the service life of the floor finishing is about 40 years. These result would be utilized to conduct the repair plan under the service life.

국방시설에 적합한 선진 유지관리예산모델의 적용에 관한 연구 (The Study on Application of Advanced Maintenance and RePairBudgeting Model for Domestic Military Facilities)

  • 박찬식;홍성호
    • 한국건설관리학회논문집
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    • 제3권4호
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    • pp.123-131
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    • 2002
  • 공공 시설물별 특성을 반영하기 힘든 Incremental Budgeting 모델에 근거한 유지관리예산의 산정 및 배정은 유지관리 요구와 투자예산간의 관련성을 더욱 격리시켜, 시설물의 조기 노후화를 발생시키고 있다. Incremental Budgeting 모델의 문제점을 개선하기 위한 노력이 일부에서 진행되고 있으나, 기존 모델의 테두리에서 이루어져 근본적인 처방이라 보기 힘들다. 공공 시설물 유지관리예산모델의 해결방안은 새로운 시각에서 바라보아야 한다 이러한 관점에서 $50\%$ 이상이 80년대 이전에 축조되었으며, 최근 대형화$\cdot$현대화되는 추세인 국방시설을 대상으로 문헌연구와 전문가 면담조사를 통해 적합한 유지관리예산모델을 선정하고, 이에 따른 현행 업무프로세스를 개선하였다.

LCC 분석에 기초한 UDPSC 교량의 유지관리비 예측에 관한 연구 (Prediction of UDPSC Bridge's Maintanence Cost based on Life Cycle Cost Analysis)

  • 심보현;이홍철;우성권
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2006년도 정기학술발표대회 논문집
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    • pp.638-641
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    • 2006
  • 본 연구에서는 UDPSC(Up-Down Precast Concrete) 교량을 유지관리하는데 발생되는 비용인 유지관리 비용의 산출 방법에 대하여 제안하였다. 신공법을 이용한 교량인 UDPSC 교량의 시공실적은 2000년도 이후 공사가 완료된 교량만 109건에 이르며, 2006년 현재 37건의 공사가 진행중에 있고 설계납품도 194건에 이른다. 이러한 시공실적에도 불구하고 신공법의 교량이라는 이유로 사용기간이 길지 않아 유지관리비에 대한 실적 데이터의 축적이 이루어지지 않았다. 때문에 건설교통부의 유지관리비 산출지침과 선행연구 분석을 통해 교량의 주요자재별 내구연한을 판단하여 유지관리비를 산출하는 방법을 제안하였으며, 실제로 시공된 교량을 토대로 유지관리비용을 산출하였다.

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인공지능 기반의 교량 보수공법 선정 기술 개발을 위한 선행 분석 (Preliminary Analysis on Artificial Intelligence-based Methodology for Selecting Repair and Rehabilitation Methods of Bridges)

  • 김종협;정인수;윤원건;김정렬;박인석
    • 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.

항공정비산업 육성을 위한 정비조직인증 컨설팅 방안 연구 (A Study on the Promotion of Approved Maintenance Organization Consulting for the Development of MRO Industry)

  • 남승주;조재현;김정호;송운경
    • 한국항공운항학회지
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    • 제30권4호
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    • pp.33-44
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    • 2022
  • As the majority of Korean MRO demand is outsourced overseas, AMO by major foreign authorities is required to promote the Korean MRO industry to keep Korean MRO demand on shore. This study aims to promote consulting for AMO (obtaining repair station certification) by U.S. Federal Aviation Administration (FAA) for Korean maintenance companies. We analyzed AMO process, studied various industry cases, developed a model for AMO consulting, and identified core competencies for consultants. We suggested a five-step modified Milan model to apply AMO consulting process. We identified seven core competencies (ethics, communications, problem-solving, technical, relationship, resource management, organizational understanding) both social and technical for consultants. Additionally, we text analyzed more than 260 FAA AMO consultant resumes on Linkedin and interpreted frequent words (airline, audit, inspector, DER, regulation, ISO, system) to their competencies. This study contributes to promote consulting for the Korean MRO industry to be recognized by FAA and to develop the Korean MRO industry.