• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.860-869
• /
• 2011

It is very important that reduce the maintenance cost and extend life time of the urban transit EMU through effective maintenance method research. The maintenance cost of the urban transit EMU shares 60%~70% of it's life cycle cost. It means that the maintenance cost is bigger than the introduction cost of the urban transit EMU. In this study, I introduces a quality control technique to improve the urban transit vehicle reliability. I suggest the control chart using quality control technique. And the control charts apply to the Static Inverter of EMU.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2004.10a
• /
• pp.157-162
• /
• 2004

Recently, Life Cycle Cost (LCC) for civil infrastructures, such as pavements, bridges, and dams, has been emphasized. However there are few cost models for road tunnel especially for maintenance phase. The road network is composed of highways, bridges, and road tunnels. Thus it is as important as for road tunnels to keep safe for traffic. The maintenance strategies for road tunnels can be achieved based on the minimization of LCC in maintenance phase. For this purpose, in this paper, cost model and cost classification for road tunnel in maintenance phase are suggested.

• Journal of Korean Society on Water Environment
• /
• v.28 no.2
• /
• pp.202-212
• /
• 2012

Due to the deterioration of water supply network and the deficiency of raw water, the water utility of local governments have performed various projects to improve their revenue water ratio. However, it is very difficult to estimate the cost for maintaining the revenue water ratio at higher level after completing the project, because local governments have different conditions affecting the operating and maintenance cost of water supply network. The purpose of this study is to present a procedure to estimate the operating and maintenance cost required to maintain the target revenue water ratio of the water supply network. For this purpose, we estimated the cost used only for operation and maintenance of water supply network of 164 local governments with the aid of K-Mean Clustering Analysis and the data from 40 representative local governments. Then, the regression analysis was performed to find relationship between revenue water ratio and the operating and maintenance cost with two different data sets generated by two classification methods; the first method classifies the local governments by means of k-means clustering, and the other classifies the local governments according to the index standardized by the operating and maintenance cost per unit length of water mains per revenue water ratio. The results shows that the method based on the index standardized by the cost and revenue water ratio of each government produces more reliable results for finding regression equations between revenue water ratio and the operating and maintenance cost only for water supply network. The estimated regression equations for each group can be used to estimate the cost required to keep the target revenue water ratio of the local government.

• Asian Journal of Turfgrass Science
• /
• v.23 no.1
• /
• pp.61-76
• /
• 2009

The purpose of this study are to investigate the reasonable maintenance expense of golf course according to the size and management system of each golf course. The maintenance cost per hole per golfer of 29 golf courses and the maintenance cost for items and locations of 8 golf courses were analyzed. 1. As golfers per hole increased, maintenance cost per hole per golfer decreased. 2. The decisive cost factors for maintenance cost of golf course are the number of annual golfers, the total course size, the management system, and automation of course facilities. 3. Maintenance cost of golf courses contained the landscaping areas except for building and parking lots is $869^{\}/_{m^2}$ Korean won. 4. Average maintenance cost of 8 golf courses is $44,325,000^{\}/_{hole}$. 5. Labor cost marked the largest portion in the total cost. Among the items of labor cost, repair cost for green ball mark was the highest with the ratio of 26%(\4,163,000). 6. Material cost for Fairways which reaches 30% of the total area was composed of $22%{\sim}44%$ of the total cost of materials. Cost of imported fertilizers, pestcides for insects and diseases, and sands for top dressing was the highest. 7. Material cost for Green which reaches 2% of the total area was composed of $28%{\sim}36%$ of the total cost. Cost of imported products such as particle-shaped fertilizers, micro mineral fertilizers, and soil conditioners was the highest. 8. There is no difference in cost between chemical fertilizers and the environmentally friendly fertilizers even if environmentally friendly fertilizers using microorganism or chitosan materials are also expensive.

• Journal of the Korean Institute of Educational Facilities
• /
• v.9 no.3
• /
• pp.5-12
• /
• 2002

This study attempts to suggest a standard for maintenance and repair cost per each unit area, by analyzing the causes and cost of various maintenance and repair work in the university facilities. The result of my study on the data of maintenance and repair work for 12 years between 1990 and 2001 in the two campuses of the university that I selected for my case study is the following. (1) The yearly average for maintenance and repair cost in the facilities of the university with 67 old and new buildings for the past 12 years was $W4,422/m^2$. In addition, the repair cost based on the calculation of the degree of decrepitude of the buildings was $W10,291/m^2$. (2) The number of causes of maintenance and repair work increase steadily every year, due to the development of universities and changes in the educational environment. A special case like a university merger also appears, which also demands maintenance and repair work of university facilities. (3) It is important that a budget for interior maintenance is increased or added to an extent, in order to minimize the maintenance and repair cost of the university facilities, and to cope with changing educational environments flexibly. (4) The publication of a white paper that includes the planning of a building, construction process, and changes in design, seems to be required for the sake of users' convenience and efficient maintenance and repair work.

• International Journal of Reliability and Applications
• /
• v.9 no.1
• /
• pp.113-122
• /
• 2008

In this paper, we consider a periodic preventive maintenance policy in which each preventive maintenance reduces the hazard rate of amount proportional to the failure intensity, which increases since the system started to operate. And the effect of preventive maintenance at each preventive maintenance epoch is different. The expected cost rate per unit time for the proposed model is obtained. We discuss the optimal number N of the periodic preventive maintenance and the optimal period x, which minimize the expected cost rate per unit time and obtain the optimal preventive maintenance schedule for given cost structures of the model. A numerical example is given for the purpose of illustrating our results when the failure time distribution is Weibull distribution.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.251-252
• /
• 2015

Enough school facility maintenance data should be accumulated in a database or data warehouse in order to supply information about school facility correct maintenance budget plan, budget assignment, and cycle and rate of maintenance or replacement. For those, this research analyze the present school facility maintenance practice and budget and construction cost structure. In order to solve the problems, this study analyze the present practice of maintenance and replacement and obtain LCC(Life cycle cost) data, perform expert interview and then establish construction work breakdown structure of maintenance of educational facility by combining work breakdown structure(WBS) and cost breakdown structure(CBS).

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.2
• /
• pp.41-48
• /
• 2018

Carbonation is one of the major detrimental factors to the reinforced concrete structures owing to penetration of atmospheric CO2 through the micro pores, thereby it reduces the durability of the concrete. The maintenance periods and cost for concrete according to the coefficient variation of different finishing materials is documented in literature. However, it is required to carry out the systematic and well planned studies. Therefore, keeping them in mind, surface repair was carried out to the carbonated concrete and the maintenance cost was calculated to measure the durability life after repair with different variable. The deterministic and probabilistic methods were applied for durability and repair cost of the concrete. In the existing deterministic model, the cost of repair materials increases significantly when the concrete structure reaches its service life. In present study using a stochastic model, the maintenance period and cost was evaluated. According to obtained results, there was no significant difference in the number of maintenance of the coefficient variation. The initial durability has a great influence on the maintenance time and cost of the structure. Unlike the deterministic model, the probabilistic cost estimating model reduces the number of maintenance to the target service life expectancy.

• Journal of Applied Reliability
• /
• v.14 no.2
• /
• pp.122-128
• /
• 2014

In this paper, we consider the periodic preventive maintenance model for a repairable system following the expiration of extended warranty under replacement-repair warranty. Under the replacement-repair warranty, the failed system is replaced or minimally repaired by the manufacturer at no cost to the user. Also, under extended warranty, the failed system is minimally repaired by the manufacturer at no cost to the user during the original extended warranty period. As a criterion of the optimality, we utilize the expected cost rate per unit time during the life cycle from the user's perspective. And then 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.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.1097-1104
• /
• 2008

Life cycle costing is one of the most effective approaches for the cost analysis of long-term life products, like as railroad vehicle. Life cycle costing includes the cost of concept design, development, manufacture, operating, maintenance and disposal. Especially, life cycle costing in the railroad industry has been focused on the maintenance cost. In this paper, we investigated the standard, guide and maintenance information of railroad vehicle. For this purpose, we suggested the unique templates of railroad vehicle maintenance information. We also performed maintenance cost analysis on the some sub-system of railroad vehicle for the case study.