• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.1D
• /
• pp.63-72
• /
• 2009

This study aims at establishing the decision-making support system for the highway assets, long-term performance presumption and evaluation of asset value, which are appropriate for Korea, and proposing the methods of the optimal engineering method and the timing decision for the preventive maintenance through the project evaluation, the optimization method and life-cycle analysis related to the highways. In order to supplement the current problem of the near-sighted budget management system, which chooses the maintenance place of the highway, depending on the level of the budget with fixed amount, the long-term required budget prediction system and the economy principle were introduced, so that the pavement agency can predict the level of the required budget, and it was aimed to develop the pavement asset evaluation system to maintain the performance of the highway with the minimum of the cost. In the use of the highway pavement asset evaluation system, to maintain the appropriate level of the pavement evaluation index, when the budget was efficiently established in the reference of the required maintenance budget for the chosen section of the highway in the year concerned, it was possible to analyze the most rational pavement maintenance budget. With this result, it is estimated to prevent the unnecessary waste of budget in advance, and through the development of the decision-making system for the long-term performance presumption and the asset value estimation of the pavement, it is expected to able to analyze the previous evaluation of the project related to the highway and the feasibility of introduction.

• Journal of KIISE:Software and Applications
• /
• v.34 no.7
• /
• pp.603-615
• /
• 2007

Software changes for various kinds of reasons and they increase maintenance cost. Software metrics, as quantitative values about attributes of software, have been adopted for predicting maintenance cost and fault-proneness. This paper proposes relationship between some typical object-oriented metrics and software changes in industrial settings. We used seven metrics which are concerned with size, complexity coupling, inheritance and polymorphism, and collected data about the number of changes during the development of an Information system on .NET platform. Based on them, this paper proposes a model for predicting the number of changes from the object-oriented metrics using multiple regression analysis technique.

• Proceedings of the KIEE Conference
• /
• 2003.07a
• /
• pp.80-82
• /
• 2003

전력계통의 수요예측은 수십 년간의 일별, 주별, 월별, 년도별 자료와 기타 수많은 계수들을 요구하므로 처리해야할 자료의 양이 방대하여, 수요예측에는 데이터베이스의 사용이 필수이다. 본 연구에서는 수요예측 및 이와 유사한 대규모 자료의 전산화에 적합한 데이터베이스 설계기법을 소개하고, 계산 수행 시 속도 및 운용의 효율성을 기하기 위한 방안을 소개한다. 또한 데이터베이스의 유지보수를 위한 기법과 각종 접근 방법의 예를 들었다.

• Korean Journal of Construction Engineering and Management
• /
• v.21 no.6
• /
• pp.46-55
• /
• 2020

The maintenance cost for highway pavement is gradually increasing due to the continuous increase in road extension as well as increase in the number of old routes that have passed the public period. As a result, there is a need for a method of minimizing costs through preventative grievance Preventive maintenance requires the establishment of a strategic plan through accurate prediction old Highway pavement. herefore, in this study, the XGBoost among machine learning classification-based models was used to develop a highway pavement damage prediction model. First, we solved the imbalanced data issue through data sampling, then developed a predictive model using the XGBoost. This predictive model was evaluated through performance indicators such as accuracy and F1 score. As a result, the over-sampling method showed the best performance result. On the other hand, the main variables affecting road damage were calculated in the order of the number of years of service, ESAL, and the number of days below the minimum temperature -2 degrees Celsius. If the performance of the prediction model is improved through more data accumulation and detailed data pre-processing in the future, it is expected that more accurate prediction of maintenance-required sections will be possible. In addition, it is expected to be used as important basic information for estimating the highway pavement maintenance budget in the future.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.38 no.4
• /
• pp.505-516
• /
• 2018

In order to establish an efficient bridge maintenance strategy, the future performance of a bridge must be estimated by considering the current performance, which allows more rational way of decision-making in the prediction model with higher accuracy. However, personnel-based existing maintenance may result in enormous maintenance costs since it is difficult for a bridge administrator to estimate the bridge performance exactly at a targeting management level, thereby disrupting a rational decision making for bridge maintenance. Therefore, in this work, we developed a representative performance prediction model for each bridge element considering uncertainty using domestic bridge inspection data, and proposed a bayesian updating method that can apply the developed model to actual maintenance bridge with higher accuracy. Also, the feasibility analysis based on calculation of maintenance cost for monitoring maintenance scenario case is performed to propose advantages of the Bayesian-updating-driven preventive maintenance in terms of the cost efficiency in contrast to the conventional periodic maintenance.

• Journal of Platform Technology
• /
• v.6 no.3
• /
• pp.47-54
• /
• 2018

Predictive analysis in the hardware industry can be performed at an appropriate point in time to prevent failure of production facilities and reduce management costs. This helps to perform more efficient and scientific maintenance through automation of failure analysis. Among them, predictive management aims to prevent the occurrence of anomalous state by identifying and improving the abnormal state based on the gathering, analysis, and scientific data management of facilities using information technology and constructing prediction model do. In this study, we made a fault tree through the Relex tool and analyzed the error code of the hardware to study the safety.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.23 no.4
• /
• pp.98-103
• /
• 2019

Integrity prediction of the operation equipment of naval vessels is essential to maintain the efficiency of the operation performance in urgent situations. Recently, the integrated condition assessment system(ICAS) was introduced and maintained to improve operational performance. This technology is related with ICAS, and it must be localized through extensive research. In this paper, we present the results of applying the data-driven model to the predictability methods of diesel generators, which are naval vessel operation equipment.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.14 no.2
• /
• pp.89-96
• /
• 2010

This study presented the analytical evaluation model effective in the concrete structure repaired with a patching material. The model considered the effect of the repair material on carbon dioxide penetration into the repaired concrete as evaluating the remaining service life of the CO2-deteriorated concrete structure after repair. The diffusion profiles of carbon dioxide as well as the carbonated concrete were effectively able to be modelled with analytical method based on Fick's 1st diffusion law. The evaluation of the model equation showed the good result and rational process quantitatively and numerically to evaluate the remaining service life of the repaired concrete structure after repair.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2007.11a
• /
• pp.205-209
• /
• 2007

생산 현장에서 기기의 운영과 관리는 제품의 품질 및 기업의 수익성과 직결된다. 그러나 정상적인 작동을 하고 있는 시스템에서 고장의 시점과 고장의 종류를 예측하기 곤란하며 따라서 잔여 가동 시간이 얼마인지도 예측하기 힘들다. 본 논문에서는 산업용 기계, 공정과 의료기기 등 신뢰성이 요구되는 Brushless DC 모터의 상태 변화의 추이를 관찰하여 진단의 특징점으로 사용한다. 본 논문에서 제안한 상태천이 모텔은 고장의 시점과 고장의 종류를 예측할 수 있으며 유지보수의사결정에 도움을 줄 수 있다.

• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 1999.06a
• /
• pp.13-18
• /
• 1999

공업의 발전과 더불어 금세기 초반부터 선박, 항공기, 지하매설물, 차량 등의 대형 파괴사고가 자주 발생하면서 이들의 파괴원인을 규명하는 연구가 활발해졌고, 이에 따라 파괴역학의 중요성이 인식되기 시작했다. 따라서 피로파괴에 대한 연구 및 이해가 크게 진전되었다[1-7］. 그러나 대, 중, 소형 기계구조물의 설계, 제작, 운용 및 구성부품과 구조물의 안전성 유지와 보수에 관심이 있는 공학자들에게는 해결되지 않은 많은 문제가 남아있다. 본 연구의 목적은 기존의 파괴역학적개념과 이를 기초로 새로 창안된 모델들이 포함된 피로수명예측 프로그램을 개발하고 이를 실제 구조물의 수명 예측에 적용하여 신뢰성을 확인하는데 있다. (중략)