• KIEAE Journal
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• 제15권6호
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• pp.19-26
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• 2015

Purpose: The repair would require to conserve and improve the building function and performance since built. Each household is responsible for maintaining the public facilities and paying the required cost. Therefore, it needs to get the tool or method to forecast the required cost in the future. Before the repair cost is provided, it needs to catch the repair cost distribution and provide the unit cost for the repair cycle. In this study, it aimed at providing the repair cost unit and analyzing the repair cost distribution in a roof proofing work, elevator work and building painting, which are divided into a fully work and partly change. Results of this study are shown that first, the average repair cost for roof proofing work is provided with $166.59{\times}10^3won/household$ and $1.59{\times}10^3won/m^2$ of a full change, $33.22{\times}10^3won/household$ and $0.33{\times}10^3won/m^2$ for a partly work. In addition, elevator work is $557.45{\times}10^3won/household$ and $5.38{\times}10^3won/m^2$ for a full change, $32.92{\times}10^3won/household$ and $0.56{\times}10^3won/m^2$ for a partly repair. Painting has a $304.48{\times}10^3won/household$ and $2.94{\times}10^3won/m^2$. Second, the distribution pattern of repair unit cost has a weibull-typed distribution which has a long tail to the right.

• 대한산업공학회지
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• 제16권2호
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• pp.45-50
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• 1990

A replacement policy with repair cost limit is discussed. When a system fails, the repair cost is estimated by inspection and repair is then undertaken if the estimated cost is less than a predetermined limit L ; otherwise the system is replaced. After repair, the system is as good as new with probability(l-p) or is minimally repaired with probability p. It is assumed that repair cost can not be estimated exactly because of inspection error. When the failure time follows a Weibull distribution and repair cost a normal distribution, the value of repair cost limit minimizing the expected cost rate is shown to be finite and unique.

• 한국신뢰성학회지:신뢰성응용연구
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• 제6권2호
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• pp.151-161
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• 2006

This article is concerned with cost analysis model in periodic maintenance policy. The repair policy is differently applied according as unit importance during an item being used and unit restoration during an item being failed. So in this paper the repair policy with minimal repair is considered as follow : as the occurrence of failure between minimal repair and periodic interval time, unit is replaced by a spare unit until the periodic maintenance time arrived. Then total expected cost per unit time is calculated according to scale parameter of failure distribution in a view of customer's. The total expected costs are included repair and usage cost : operating, fixed, minimal repair, periodic maintenance and spare unit cost. Numerical example is shown in which failure time of item has Erlang distribution.

• 산업경영시스템학회지
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• 제20권43호
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• pp.241-247
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• 1997

This paper is concerned with cost analysis model in free-replacement policy. The free-replacement policy with minimal repair is considered as follows; in a manufacturer's view point operating unit is periodically replaced, if a failure occurs between minimal repair and periodic maintenance time, unit is remained in a failure condition. Also unit undergoes minimal repair at failures in minimal-repair interval. Then total expected cost is calculated according to the parameter of failure distribution in a view of consumer's. The expected costs are included repair cost and usage cost: operating, fixed, minimal repair and loss cost. Numerical example is shown in which failure time of item has weibull distribution.

• 산업경영시스템학회지
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• 제18권36호
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• pp.287-295
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• 1995

This paper is concerned with cost analysis model in periodic maintenance policy. Generally periodic maintenance policy in which item is repaired periodic interval times. And in the article minimal repair is considered. Mimimal repair means that if a unit fails, unit is instantaneously restored to same hazard rate curve as before failure. In the paper periodic maintenance policy with minimal repair is as follows; Operating unit is periodically replaced in periodic maintenance time, if a failure occurs between minimal repair and periodic maintenance time, unit is replaced by a new item until tile periodic maintenance time comes. Also unit undergoes minimal repair at failures in minimal-repair-for-failure interval. Then total expected cost per unit time is calculated according to scale parameter of failure distribution. Maintenance cost factors are included operating, fixed, minimal repair, periodic maintenance and new item replacement cost. Numerical example is shown in which failure time of system has weibull distribution.

• 산업경영시스템학회지
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• 제18권34호
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• pp.139-146
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• 1995

This study is concerned with cost analysis in periodic maintenance policy. Generally periodic maintenance policy in which item is repaired periodic interval times. And in the article minimal repair is considered. Minimal repair means that if a unit fails, unit is instantaneously restored to same hazard rate curve as before failure. In the paper periodic maintenance policy with minimal repair is as follows; Operating unit is periodically replaced in periodic maintenance time, if a failure occurs between minimal repair and periodic maintenance time, unit is replaced by a spate until the periodic time comes. Also unit undergoes minimal repair at failures in minimal-repair-for-failure interval. Then total expected cost per unit time is calculated according to maintenance period and scale parameter of failure distribution. Total cost factors ate included operating, fixed, minimal repair, periodic maintenance and replacement cost Numerical example is shown in which failure time of system has erlang distribution.

• 한국건설순환자원학회논문집
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• 제6권3호
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• pp.153-159
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• 2018

지하구조물에 주로 발생하는 탄산화는 콘크리트 내부의 공극수의 pH감소에 따라 부식을 유발할 수 있으므로 많은 연구가 진행되고 있다. 그러나 이산화탄소로부터 표면을 보호하는 간단한 표면 보수방법을 통하여 구조물의 내구수명의 연장이 가능하다. 기존의 결정론적 유지관리 기법과는 다르게, 확률론적 유지관리 기법에서는 내구수명의 변동성이 고려될 수 있으나 정규분포만 다루고 있다. 본 연구에서는 정규분포 이외에 로그분포를 고려할 수 있는 수명-확률분포를 유도하였으며, 이를 기초로 다양한 수명-확률분포 함수를 고려한 보수비 산정기법을 제안하였다. 제안된 기법은 초기의 내구수명 분포 또는 보수재를 통하여 연장된 내구수명 분포가 정규 또는 로그분포를 가질 경우 목표내구수명의 연장에 따라 확률론적 기법을 통하여 보수비를 평가할 수 있다. 보수를 통한 내구수명이 로그분포를 가질 경우 효과적으로 보수비를 감소시킬 수 있으며, 장기 실험 또는 실태조사를 통하여 내구수명 분포가 정의될 수 있다면 더욱 합리적인 유지관리 계획을 수립할 수 있을 것으로 판단된다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제6권3호
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• pp.195-203
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• 2006

This paper deals with cost analysis model in periodic maintenance policy. The repair policy with minimal repair is considered as follow : as the occurrence of failure between minimal repair and periodic interval time, unit is replaced by a new unit before the periodic maintenance time comes. Then total expected cost per unit time is calculated according to time delta t in a view of customer's. The total expected costs are included repair and usage cost : operating, fixed, minimal repair, periodic maintenance and new unit expected cost. Numerical example is shown in which failure time of item has Normal distribution.

• 한국구조물진단유지관리공학회 논문집
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• 제23권2호
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• pp.10-19
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• 2019

염해에 콘크리트 구조물은 사용기간의 증가에 따라 내구성에 문제가 발생하므로 보수를 포함한 유지관리가 필수적이다. 일반적으로 결정론적인 방법으로 내구수명이 결정되고 이에 따라 유지관리비가 평가되고 있으나, 확률론적 유지관리 기법을 고려할 경우 연속적인 보수비용이 평가되므로 합리적인 유지관리가 가능하다. 기존의 확률론적 유지관리 기법에서는 정규분포만 고려되었으나, 본 연구에서는 초기 내구수명 및 보수에 따른 수명-확률함수에 로그함수를 고려할 수 있도록 개선되었으며, OPC 및 GGBFS를 사용한 콘크리트에 대하여 보수비용을 평가하였다. 로그 함수를 가지는 수명-확률함수는 중앙값 이전보다 이후에 미치는 영향이 지배적이므로 초기 내구수명 분포에 유리하며 전반적으로 낮은 보수비용을 도출할 수 있다. GGBFS를 사용한 콘크리트는 OPC 콘크리트 비하여 높은 내구수명과 낮은 보수횟수를 통하여 30% 수준으로 보수비가 감소하였다. 본 연구에서 도출된 확률론적 유지관기 기법은 정규분포 뿐 아니라 로그분포를 가지는 수명-확률함수를 초기 및 다양한 보수시기에 적용할 수 있는 장점을 가지고 있으며, 더욱 합리적인 보수비용을 도출할 수 있다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제12권2호
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• pp.57-66
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• 2012

In this paper, we consider the periodic preventive maintenance model for a repairable system following the expiration of replacement-repair warranty. Under this preventive maintenance model, we derive the expressions for the expected cycle length, the expected total cost and the expected cost rate per unit time. Also, we determine the optimal preventive maintenance period and the optimal preventive maintenance number by minimizing the expected cost rate per unit time. Finally, the optimal periodic preventive maintenance policy is given for Weibull distribution case.