세계적수준의 설비관리 프레임워크 개발

구성태 대한산업공학회 2020 대한산업공학회지 Vol.46 No.3

The purpose of this study is to develop a world class maintenance framework for manufacturing innovation and safe operation of critical facilities. The new world class maintenance framework was developed by analyzing the world class maintenance framework presented in previous studies and evaluating the commonality of maintenance elements, the relevance of maintenance departments, and the expertise of maintenance work. The study presented four maintenance subsystems, one support tool, and 18 implementation elements for world class maintenance. The proposed framework reflects the characteristics of maintenance processes and maintenance tasks such as maintenance strategies, input elements, maintenance systems, and output elements, which are not presented in previous studies. The proposed framework is meaningful in that it presents a clear implementation elements and directions for innovation of maintenance to companies or researchers who want to improve maintenance to a global level.

유지관리 모니터링을 통한 국가어항 방재시스템의 유지관리수준에 관한 연구

조영진,김영서 (사)한국연안방재학회 2019 한국연안방재학회지 Vol.6 No.2

The breakwater of the national fishery port is currently under going rapid aging and the possibility of destruction due to climate change is increasing and maintenance costs are expected to rise sharply. Therefore, it is necessary to reduce the cost of LCC by securing the safety of the national fishery port breakwater and long life. Based on this recognition, this study defines the maintenance level of the national fishery port breakwater and suggests appropriate maintenance level for rational decision making of maintenance. The appropriate maintenance level of national fishery port breakwater is as follows: 1. The maintenance according to service life of facilities is current maintenance level, 2. The maintenance according to breakwater damage rate is Current maintenance level or preventive maintenance level, 3. The maintenance according to change in design wave is preventive maintenance level.

보전조직이 보전성과지표에 미치는 영향에 관한 연구

구성태(Sung Tae Ku),김창은(Chang Eun Kim) 대한산업공학회 2013 대한산업공학회지 Vol.39 No.6

This study is intended to propose optimal maintenance organization to process industry, especially paper industry by analyzing maintenance organization of paper industry and finding out how the maintenance organization and the allocation of maintenance resources influence maintenance performance indices here in this paper. In this study, we analyzed the maintenance organization in detail and studied correlation between maintenance organization and equipment failure rate for the major top six domestic paper-mills in market share. According to the study, the maintenance organization has been changed in accordance with its business environment, but its performance was different by both the allocation way of maintenance resources and the structure of maintenance organization. For paper industry, whose availability is the most important key index that determines the success or failure of a business, it turns out to be the most effective strategy that operates the combination maintenance combined central maintenance with area maintenance and allocates the maintenance resources mainly for preventive maintenance. In particular, it turned out to be that there is the strong positive correlation between the rate of shift workers and the equipment failure rate. The results of this study is not limited to paper industry, but expandable to other industry. So it is expected that the direction of the maintenance organization would be given to the company which is struggling to improve its availability.

An Introductory Study on ImPerfect Maintenance Effect in Rolling Stocks

Jong Woon Kim,Seok Yun Han,Jong Duk Chung 한국철도학회 2008 International Journal of Railway Vol.1 No.2

On the cultivation of psychological competence among aircraft maintenance major students

Yuhang Fang HONG KONG ACADEMY OF SOCIAL SCIENCES 2024 Journal of Social Science Development Research Vol.2 No.2

The strategy of a strong civil aviation country points out that China should be built into a strong civil aviation country with international competitiveness. Aircraft maintenance ensures the safety of aircraft and passengers, and plays a crucial role in the strategy of a strong civil aviation country. The arduous work situation in the aircraft maintenance industry greatly affects the psychological quality of aircraft maintenance practitioners. Aircraft maintenance students even develop a sense of fear and are unwilling to work in airlines and maintenance companies. Based on the current psychological status of aircraft maintenance students, this article proposes an implementation path to cultivate their competent psychological qualities. The cultivation of psychological competence among students majoring in aircraft maintenance needs to be carried out from multiple aspects. Through the joint efforts of family, school, and enterprise, we will ensure the mental health of students majoring in aircraft maintenance. Reduce anxiety and confusion among students majoring in aircraft maintenance through clear career planning. By simulating the work environment and content through practical courses and pre job training, we aim to improve the psychological competence of students majoring in aircraft maintenance. Exploring the cultivation path of psychological competence for aircraft maintenance students can help improve their psychological and skill levels, laying a solid foundation for their future career development.

창정비방침(정비원, 정비형태, 요소개발비) 설정을 위한 머신러닝 예측모델

강경환,심영락,김호성 한국방위산업학회 2024 韓國防衛産業學會誌 Vol.31 No.2

창정비를 위한 창정비 대상품목, 창정비형태, 창정비원, 요소개발에 필요한 요소개발비 등은 창정비방침에 따라 결정된다. 획득과 운영유지의 효율적인 연계를 위해서는 소요기획 단계부터 창정비방침에 대한 검토가 필요하다. 창정비에 대한 개념을어떻게 설정하느냐에 따라 설계와 향후 운영유지에 미치는 영향이 크기 때문이다. 본 연구에서는 획득단계 초기 또는 창정비방침 설정간 활용할 수 있는 머신러닝 예측모델을 제시하였다. 종속변수로서 창정비 수행여부, 창정비 형태(계획정비 또는 고장정비), 창정비원(군직 또는 외주), 병행정비(군직과 외주), 창정비 요소개발비를 선정하였다. 독립변수로서 장비가격, 전력화대수, 시스템 단위(전체 또는 구성품), 요소개발 부품수를 선정하였다. 머신러닝에 활용한 통계모형은 로짓(Logit), 프로빗(Probit), 선형확률모형(LPM)으로 육군에서 분석한 33개의 창정비 분석 자료를 활용하여 학습과 테스트를 수행하였다. 실험결과 로짓(Logit) 모형의 정확도가 가장 높았으며, 각 종속변수의 정확도는 최대 100%, 평균 65%~93%로 나타났다. According to the depot maintenance policy, the depot maintenance item, source, type and the development cost are determined. In order to efficiently link acquisition and operation, it is necessary to review the depot maintenance policy from the planning stage. This is because, depending on how the concept of depot maintenance is set, it has a great impact on the design and future operation and maintenance. In this study, a machine learning prediction model that can be used at the beginning of the acquisition stage or during the establishment of the depot maintenance policy was presented. Whether of not depot maintenance is carried out, depot maintenance source, depot maintenance type and development cost for depot maintenance element are dependent variables. The independent variables are the price of equipment, the quantity, the number of components. The statistical model used for machine learning were Logit, Probit, LPM(Linear Probability Model), and 33 depot maintenance analysis data were trained and tested. As a result of the experiment, the accuracy of the Logit model was the highest, and the accuracy of dependent vairables was up to 100%, and the average accuracy was 65%~93%.

K-56 탄약운반장갑차 창정비 형태 및 창정비 주기설정에 관한 연구

강경환(Kyung Hwan Kang) 한국산학기술학회 2024 한국산학기술학회논문지 Vol.25 No.8

창정비는 정비형태에 따라 고장정비와 순환정비로 구분이 된다. 고장정비는 고장 난 해당 구성품을 정비창으로 후송하여 수리를 수행하는 비계획정비이다. 순환정비는 순환주기를 설정하고, 순환주기 도래 시 완성 장비를 정비창으로 후송하여 완전분해 수리를 수행하는 계획정비이다. 어떠한 정비형태를 정비방침으로 설정하느냐에 따라 총 수명주기의 정비비용은 달라진다. 순환정비를 수행할 경우, 최적의 순환주기를 설정하는 것 또한 경제성 측면에서 중요한 의사결정 요소이다. 본 연구에서는 창정비 형태와 최적의 순환주기 설정을 위한 비용분석을 수행하였다. 정비비용은 부대 및 야전 정비비, 비계획 창정비비, 계획 창정비비로 구성이 된다. 각 비용은 공인된 물가상승률과 임률, 방위사업청의 비용분석 지침, 정비창의 실제 정비원가 자료 등을 활용하여 분석의 신뢰도를 높였다. K-56 탄약운반장갑차의 향후 30년간 정비 비용 분석결과, 순환정비비는 약 5,646억원, 고장정비비는 약 1조 1,460억 원으로 산출되어 순환정비를 수행하는 것이 효과적이다. 순환주기 분석결과, 15년 차(5,645.8억 원), 16년 차(5,617.7억 원), 17년 차(5,622.9억 원)의 총 수명주기 비용은 1 % 미만의 차이로 15년 차부터 17년 차 사이에 수행하는 것이 경제적인 것으로 분석되었다. Depot maintenance is divided into breakdown maintenance and cyclical maintenance depending on the type. Breakdown maintenance is unscheduled-the broken component is transported to a depot for repair. Cyclical maintenance occurs when a cycle was set and has arrived, so the equipment is transported to a depot for overhaul. The total life cycle cost varies depending on the maintenance policy. When performing cyclical maintenance, setting the optimal cycle is an important factor in terms of economic efficiency. In this study, cost analysis determines the maintenance type and the optimal cycle. Maintenance costs comprise organizational/field maintenance, unscheduled depot maintenance, and scheduled maintenance. For the cost of each type, reliability of the analysis increases by using the official inflation rate, the labor rate, the DAPA cost analysis guidelines, and actual maintenance cost data from the depot. From analyzing maintenance costs of K-56 ammunition resupply vehicles over 30 years, cyclical maintenance costs about 564.6 billion won, and breakdown maintenance costs about 1.146 trillion won, making it effective to carry out cyclical maintenance. As a result of the cycle analysis, total life cycle costs for the 15th year (564.58 billion won), the 16th year (561.77 billion won), and the 17th year (562.29 billion won) were less than 1%, showing it is economical to conduct cyclical maintenance between the 15th and 17th years.

사출성형 공정에서의 통합정비방법에 관한 연구

박철순(Chulsoon Park),문덕희(Dug Hee Moon),성홍석(Hongsuk Sung),송준엽(Junyeop Song),정종윤(Jongyun Jung) 한국산업경영시스템학회 2015 한국산업경영시스템학회지 Vol.38 No.3

Recently as the manufacturers want competitiveness in dynamically changing environment, they are trying a lot of efforts to be efficient with their production systems, which may be achieved by diminishing unplanned operation stops. The operation stops and maintenance cost are known to be significantly decreased by adopting proper maintenance strategy. Therefore, the manufacturers were more getting interested in scheduling of exact maintenance scheduling to keep smooth operation and prevent unexpected stops. In this paper, we proposedan integrated maintenance approach in injection molding manufacturing line. It consists of predictive and preventive maintenance approach. The predictive maintenance uses the statistical process control technique with the real-time data and the preventive maintenance is based on the checking period of machine components or equipment. For the predictive maintenance approach, firstly, we identified components or equipment that are required maintenance, and then machine parameters that are related with the identified components or equipment. Second, we performed regression analysis to select the machine parameters that affect the quality of the manufactured products and are significant to the quality of the products. By this analysis, we can exclude the insignificant parameters from monitoring parameters and focus on the significant parameters. Third, we developed the statistical prediction models for the selected machine parameters. Current models include regression,exponential smoothing and so on. We used these models to decide abnormal patternand to schedule maintenance. Finally, for other components or equipment which is not covered by predictive approach, we adoptedpreventive maintenance approach. To show feasibility we developed an integrated maintenance support system in LabView Watchdog Agent and SQL Server environment and validated our proposed methodology with experimental data.

야전운용제원과 신뢰도중심정비에 기반한 장갑차 암내장형 유기압 현수장치(ISU) 정비계획 최적화

이현석,이두열 한국신뢰성학회 2024 신뢰성응용연구 Vol.24 No.1

Purpose: This study utilizes reliability-centered maintenance (RCM) to analyze the in-armed suspension unit (ISU) of armored vehicles. The aim is to propose a maintenance schedule that minimizes maintenance costs based on the RCM analysis. Methods: Fault tree analysis was performed to define the failure modes of the armored vehicle ISU system. The life distribution parameters for each part of the ISU were estimated using field operation data. Subsequently, the probability of failure and the number of expected failure events of a reference group comprising 100 armored vehicles were calculated by considering operation time. Lastly, a parametric study was conducted to determine the optimal maintenance schedule. Results: This study utilizes RCM to present the root cause of ISU failure and its consequences. Considering the targeted operational time, the optimal maintenance schedule was 90 h of operation for 100 armored vehicles. Performing maintenance at this interval resulted in the lowest maintenance costs. Conclusion: Introducing maintenance after every 90 h of operation instead of the current corrective maintenance scheme is expected to reduce the frequency of unexpected failures and minimize the costs associated with unscheduled maintenance. This method can be applied to other equipment subject to gradual deterioration to determine the optimal maintenance schedule.

원자력발전소 가동중정비 대상계통 및 기기 선정 방법론 개발

이영주,조경수,김재성 한국에너지학회 2023 에너지공학 Vol.32 No.3

Overseas nuclear power plants such as the U.S. have been actively implementing maintenance during operation by utilizing risk information since the late 1990s, whereas domestic nuclear power plants have specified that they cannot intentionally enter limited condition of operation for preventive maintenance in their technical specifications. However, discussions on implementation of on-line maintenance using risk information have recently restarted in Korea Hydro & Nuclear Power(KHNP). In this paper, the target systems & components selection methodology and application results for on-line maintenance using the currently operating preventive maintenance program were presented. The systems included in the level 1 Probabilistic Safety Assessment (PSA) evaluation and systems evaluated as functions of high safety significance in the MR (Maintenance Rule) were selected as target systems for on-line maintenance. As a target components selection method, the Functional Equipment Group (FEG) was used for the target system for on-line maintenance. To estabish the functional equipment group, a representative component for each system was selected from the point of view of on-line maintenance, and then, based on this, the maximum range of components that functionally do not affect other systems were considered, and additionally, components that support the functions of this representative component were also included. In addition, it was possible to evaluate the time required for each maintenance work and work details by linking the maintenance items developed as the corresponding maintenance work items in each functional equipment group. Lastly, for the maintenance work of the selected equipment, a work evaluation procedure was prepared in terms of maintenance risk, power plant shutdown, and industrial safety to facilitate the composition of the work package. As a result of applying this methodology to Saeul 1, an APR1400 nuclear power plant, 39 systems out of a total of 153 systems were selected as target systems, and a total of 447 functional equipment groups were developed for 31 systems, excluding 8 power-related systems. In addition, the maximum maintenance duration time of each functional equipment group was evaluated so that it could be used as out of service time, which is essential for maintenance risk evaluation and work management plan establishment.