• Journal of the Korean Institute of Landscape Architecture
• /
• v.29 no.5
• /
• pp.1-19
• /
• 2001

This paper is designed to find and develop new concepts for the sustainable traditional village in Korea. To this end, it is necessary that concern for the traditional village should diversify and expand, and not concentrate solely on the cultural properties and architecture-oriented historic elements. In consideration of this notion, this paper suggests introduction of maintenance and management as a practical concept for the embodiment of the sustainable traditional village. This paper aims to explore the concrete maintenance and management systems of Korean and Japanese cases, to analyze differences and characteristics between the two nation\\\\`s, and through these comparisons, to suggest sustainable maintenance and management methods for the traditional village in Korea. Primary data was collected by field and interview survey on each village in the two nations several times during about a two year period. The major findings of this paper are presented in three categories--maintenance management frame, maintenance management contents, and necessary principles for progressive maintenance management, and are as follows; In the first step, suggests the basic directions, boundaries, and systems for the maintenance and management of sustainable traditional villages. And in the second step, analyzes the relationship among the contents of maintenance and management methods with focus on the village space, village attraction, and village community. Our results suggests diverse maintenance and management contents for the sustainable village maintenance and management. Finally, the basic principles for the application, and use as valuable tools for sustainable village maintenance and management, are strongly recommended.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.935-940
• /
• 2006

Present periodic maintenance activities are carried on electric rolling stock in Korea based on predetermined inspection intervals. And this can be seen as a first generation of maintenance techniques without taking into consideration a degree of aging or degradation of the componets. In this study, we have analyzed the current status of maintenance being used in the techniques in various activities such as overseas railway operation organization, and good cases for the advanced country's maintenance system being carried out effectively. Based on the analysis, we would derive implications for efficient application and improvement guidance of maintenance system in electric rolling stock.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.58 no.4
• /
• pp.410-415
• /
• 2009

With the implementation of electric power industry reform, the utilities are looking for effective ways to improve the economic efficiency. One area in particular, the equipment maintenance, is being scrutinized for reducing costs while keeping a reasonable level of the reliability in the overall system. Here the conventional RCM requires the tradeoff between the upfront maintenance costs and the potential costs of losing loads. In this paper we describe the issues related to applying so-called the "Reliability-centered Maintenance" (RCM) method in managing electric power distribution equipment. The RCM method is especially useful as it explicitly incorporates the cost-tradeoff of interest, i.e. the upfront maintenance costs and the potential interruption costs, in determining which equipment to be maintained and how often. In comparison, the "Time-based Maintenance" (TBM) method, the traditional method widely used, only takes the lifetime of equipment into consideration. In this paper, the modified Markov model for maintenance is developed. First, the existing Markov model for maintenance is explained and analyzed about transformer and circuit breaker, so on. Second, developed model is introduced and described. This model has two different points compared with existing model: TVFR and nonlinear customer interruption cost (CIC). That is, normal stage at the middle of bathtub curve has not CFR but the gradual increasing failure rate and the unit cost of CIC is increasing as the interruption time is increasing. The results of case studies represent the optimal maintenance interval to maintain the equipment with minimum costs. A numerical example is presented for illustration purposes.

• Journal of Applied Reliability
• /
• v.16 no.3
• /
• pp.224-230
• /
• 2016

Purpose: Military maintenance involves corrective and preventive actions carried out to keep a system in or restore it to a predetermined condition. This research develops an optimal maintenance cycle for aviation oil testing equipment with acceptable reliability level and minimum maintenance cost. Methods: The optimal maintenance policy in this research aims to satisfy the desired reliability level at the lowest cost. We assume that the failure process of equipment follows the power law non-homogeneous Poisson process model and the maintenance system is a minimal repair policy. Estimation and other statistical procedures (trend test and goodness of fit test) are given for this model. Results: With time varying failure rate, we developed reliability-based maintenance cost optimization model. This model will reduce the ownership cost through adopting a proactive reliability focused maintenance system. Conclusion: Based on the analysis, it is recommended to increase the current maintenance cycle by three times which is 0.5 year to 1.5 years. Because of the system's built-in self-checking features, it is not expected to have any problems of preventative maintenance cycle.

• Korean Journal of Construction Engineering and Management
• /
• v.6 no.3 s.25
• /
• pp.111-119
• /
• 2005

The degree to which the design of a building embraces maintenance considerations has a great impact on its performance. Modern buildings are designed to meet higher building standards than in previous times. As the result, the influence of design on the maintenance of buildings is greater than ever before. The issue of building maintenance is a universal one and its consideration at the design stage is of great importance on the future performance of the building. Even though many studies have conducted to improve building performance, almost all of the results of those studies have not been utilized effectively during design. The purpose of this paper is to suggest a checklist which could be used for incorporating building maintenance concept in the design. The suggested checklist was made by reviewing previous studies and then refined through consulting with professionals of relevant fields.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.776-777
• /
• 2011

조속기는 수차발전기의 핵심을 담당하는 두뇌라고 말할 수 있으며, 전력계통의 부하(주파수)가 변할 경우 수차발전기의 회전속도를 정격으로 유지시켜 양질의 전기를 생산하도록 항시 조정되는 역할을 한다. 최근 조속기는 디지털화되어 최적제어 감시 및 보호기능을 수행하고 있으나 문제점도 하나둘씩 나타나고 있는 실정이다. 본 논문에서는 디지털 가버너의 Isolation Mode에 대한 설명과 사고사례를 통해 디지털가버너 운영 시 문제점을 분석, 검토하여 보완하고자 하였으며, 이를 통해 안정적으로 전력공급을 주요 목적으로 하였다.

• Structural Monitoring and Maintenance
• /
• v.2 no.2
• /
• pp.133-143
• /
• 2015

Civil engineering infrastructure is aging and requires cost-effective maintenance strategies to enable infrastructure systems operate reliably and sustainably. This paper presents an approach for determining risk-cost balanced repair strategy of corrosion damaged reinforced concrete structures with consideration of uncertainty in structural resistance deterioration. On the basis of analytical models of cover concrete cracking evolution and bond strength degradation due to reinforcement corrosion, the effect of reinforcement corrosion on residual load carrying capacity of corroded reinforced concrete structures is investigated. A stochastic deterioration model based on gamma process is adopted to evaluate the probability of failure of structural bearing capacity over the lifetime. Optimal repair planning and maintenance strategies during the service life are determined by balancing the cost for maintenance and the risk of structural failure. The method proposed in this study is then demonstrated by numerical investigations for a concrete structure subjected to reinforcement corrosion. The obtained results show that the proposed method can provide a risk cost optimised repair schedule during the service life of corroded concrete structures.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.22 no.49
• /
• pp.89-98
• /
• 1999

The objective of this study is to develop an improved algorithm for layout problems. Computerized facility layout program was also applied to solve the layout problem in locomotive maintenance workshop. The current facility layout is structured in the large space without considerations of many variable factors. For this reason, effectiveness of layout results in loss on effective space utility. This study is to develop an algorithm in the consideration of importance weight and desirable shape of specific department in the computerized layout planning and quantitative relationship rating between each department was used. Standard process duration of locomotive maintenance workshop was used to select the main activities of locomotive maintenance work. This study could generate more efficient facility layout design to reduce the number of movement frequency and travel distance in maintenance workshop.

• KIEE International Transactions on Power Engineering
• /
• v.5A no.4
• /
• pp.331-338
• /
• 2005

In this paper, an improved maintenance scheduling approach suitable for the competitive environment is proposed by taking account of profits and costs of generation companies and the formulated combinatorial optimization problem is solved by using Reactive Tabu search (RTS). In competitive power markets, electricity prices are determined by the balance between demand and supply through electric power exchanges or by bilateral contracts. Therefore, in decision makings, it is essential for system operation planners and market participants to take the volatility of electricity price into consideration. In the proposed maintenance scheduling approach, firstly, electricity prices over the targeted period are forecasted based on Artificial Neural Network (ANN) and also a newly proposed aggregated bidding curve. Secondary, the maintenance scheduling is formulated as a combinatorial optimization problem with a novel objective function by which the most profitable maintenance schedule would be attained. As an objective function, Opportunity Loss by Maintenance (OLM) is adopted to maximize the profit of generation companies (GENCOS). Thirdly, the combinatorial optimization maintenance scheduling problem is solved by using Reactive Tabu Search in the light of the objective functions and forecasted electricity prices. Finally, the proposed maintenance scheduling is applied to a practical test power system to verify the advantages and practicability of the proposed method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.3
• /
• pp.7-15
• /
• 2013

In lighting design, the calculation of maintenance factor is performed by calculation considering light source, characteristics of luminaire and environmental factors. The method to calculate the current maintenance factor applied to tunnel lighting design takes into consideration only pollution factors in tunnels. In addition, the calculation method should be change in response to changes of tunnel conditions and used light sources. In this study, the calculated factor of the maintenance factor in tunnel is determine by four calculation factors generally applied to the calculation of maintenance factor. This study examined the method of calculating the maintenance factor of tunnel lighting that can be applied according to the installation conditions in designing tunnel lighting by applying the actual installation data of luminaire.