• Proceedings of the KSR Conference
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• 2002.05a
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• pp.220-227
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• 2002

Now, Korea National Railroad is planning many ways to increase the maximum operating speed of train up to 200km/h by 2010. Among those ways, connecting conventional line with the KTX is the strongest alternative. Mostly, conventional lines are consisting of both KS50N and KS6O rail. However, the excessive abrasion might be occurred between wheel and rail when the KTX designed to operate on UIC60 is operating on the conventional line. On this study, new standard of 60kg-class rail considered suitability for both KTX and wheel used in conventional line is presented. It seems to be an effective solution for increasing maintenance costs expected when commercial speed of conventional line is increasing.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.759-767
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• 2021

Most weapons systems that are Force Integration are expensive equipment that reflects the latest technology, and the operation and maintenance cost is increasing continuously. Factors that efficiently operate and maintain these weapon systems include maintenance plans, economic costs, and repair part requirements. Among them, predicting the repair parts requirements during the life cycle in advance is an important way to increase operation and maintenance cost efficiency and operating availability. The start of requirement analysis for repair parts is a calculation of the CSP (CSP: Concurrent Spare parts, CSP hereafter) that is distributed when the weapon system is deployed. The CSP is an essential component of achieving the operating availability during this period because the weapon system aims to successfully perform a given operation mission without resupply for an initial set period. In the present study, the CSP calculation method was analyzed, reflecting the failure rate and operating time of items, but the analyzed CSP was aimed at preparing for technical failure, but in the initial operating environment, it is limited in coping with unexpected failures caused by human error. The failure is not included in the scope of free maintenance and is a serious factor in making the weapon system inoperable during the initial operation period. To prevent the inoperable status of a weapon system, CSP that considers human error is required in the initial operating environment, and the calculation criteria and measures are proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.28-36
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• 2018

Islands are supplied with power from diesel generation or from photovoltaic power generation, and problems with offshore environmental impacts (age deterioration, salt pollution), environmental pollution (exhaust gas, noise, dust) and power generation costs (installation, maintenance) have increasingly emerged. In 2016, the cost recovery rate was only 27%, and deficits reached 73% on 65 islands managed by KEPCO. In terms of deficits, the costs incurred in the power generation sector accounted for 91%, with the ratio of fixed costs at about 60%. Analysis suggests that operating costs can be reduced with an optimal power supply system that improves power generation efficiency and makes operating systems more efficient. Therefore, it is possible to simplify fuel transportation and facility maintenance, because one island integrates the power plants of remote islands, and offshore cable is used to supply power to the other islands. From the economic evaluations in this paper, an algorithm deciding offshore cable layout validity for an integrated power supply between adjacent islands is presented. Simulation results based on the proposed algorithm confirmed that an integrated power supply is economical for existing stand-alone operations on islands having diesel generation, low peak power, and near distances.

• Journal of Biosystems Engineering
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• v.10 no.1
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• pp.69-75
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• 1985

For the purpose of estimating the operating cost for feed production, energy consumption, labor requirement, maintenance cost, and supplies and miscellaneous costs are analyzed and developed as mathematical models. Mathematical model for energy usage Consists of electrical energy, boiler fuel energy and vehicle fuel energy. The mathematil model for electrical energy usage for the swine and poultry feed mill and the complete pelleted feed mill are developed, based on the general model mill and the computer program for its design developed in Kansas State University (Park, 1982). Also, the boiler fuel energy consumption model and the vehicle fuel energy consumption model are developed by analyzing the boiler system and the vehicle operation in the warehouse. In order to develop a mathematical model for labor requirement, the data that Vosloh (1968, 1976) constructed for labor requirement in his model mill are used by assuming that his model mill is similar to this model, in terms of labor assignment standards. Maintenance and repair costs are obtained by assuming to be 5.5% of the total capital investment cost. Also, supplies and miscellaneous costs are estimated by using Vosloh's report and it is approximately 0.87 dollars per ton based on daily production.

• Journal of the Korea Institute of Building Construction
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• v.2 no.1
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• pp.155-162
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• 2002

In this research, I finally came to a conclusion analyzing the connection among managing of each items in management expenses, the size of each complex and stories, and the term of using. (1) In the managing cost regarding to the management manner, although the managing cost of self-governing management is less imposed than the one of commission management, there is slight difference between those Costs. And it is more important to consider the effectiveness of management than to emphasize reduction of management cost. (2) The higher the stories, the higher the managing cost of elevator per the unit area. It Is caused by the fact that the father the distance of the elevator operating, the higher the electric charges. (3) The third of one of total management cost goes to pay the personnel expenses. So I found that the effective management of the expenses is available to reduce management cost. (4) The higher the stones, the lower the cost of personnel expenses including the cleaner cost. (5) The sum of costs assigned in repairment and management increases in proportion to the term of using. The costs assigned in special repairment and management are interacting to each other. (6) To reduce the management cost, we have to cut down the personnel in security guard that occupies one third of total management cost with application to the joint security system and operation of the self-governing guard. Through this process, it will be easy to accomplish the rationalization of contract with an outside order. Because the improvement of management service is not only the responsibility of owner but also the one of dwellers. And it Is imperative to realize the importance of cooperation and trust between the owner and dwellers. And the establishment of effective managing system which has convenience and rationality must be settled without delay.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.259-266
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• 2020

This study analyzes the effects of the obsolescence assets on the asymmetry of costs. Cost asymmetry refers to a lower percentage of costs when sales fall than increases in costs when sales increase. the obsolescence asset induces various decisions, including high maintenance costs and management improvements and replacement of facilities. This study is to analyze the cost behavior according to those decisions. The analysis showed that the higher the obsolescence of assets rate, we found cost elasticity, with a greater reduction in costs when sales decrease than the increase in costs when sales increase. Second, the lower the cost will not appear as the obsolescence of assets rate increases in case that the concentration of an item of property, plant and equipment is high, and when sales decrease. The above result means that the obsolescence of assets rate acts as operating risk and thus operates resources flexibly according to changes in sales, but when the concentration of property, plant and equipment is high, the decision-making constraint make it difficult for the flexible operation.

• Journal of the Korea Institute of Building Construction
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• v.6 no.1 s.19
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• pp.87-91
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• 2006

Since water leakage and cracks are not the source of serious problems such as long-term lowering of performance and durability of a stricture, including damages to operating facilities of a structure, damages to internal finishing materials, exhibition, and goods, and pollution of residential environment, they might have led to development of positive coping skills; however, an instant loss of lives or property due to earthquake, explosion, typhoon, or a fire was indeed neglected. In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if this costs a lot. It was not arrange the standard for construction methods of sealer of injection type for leakage maintenance, even it has been used various type of construction methods for leakage part. In conclusion, we suggest that the construction methods of sealer of injection type for leakage maintenance for leakage to establish the leakage repairing technology as increase of structure demand. Therefore, it would be possible to provide a stage-by-stage solution by developing systematic research activities among the industry, schools, and research institutes to spread maintenance management techniques globally through technical solution to water leakage and cracks, acquisition of structural safety with prolonged durability for life cycle, reduction of water leakage repair expense s, and so on.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.11
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• pp.1279-1287
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• 2009

An increasingly competitive business environment has been concentrated on industries to reduce the operating costs. Industries such as gas, oil, petrochemical, chemical, and electric power have employed for the operation and used for large equipment or structures that require a high capital investment. In order to meet these requirements, the industries are increasingly moving toward saving the experimental verification and computer simulation. Therefore industries to reduce the maintenance costs without compromising the operational safety have been forced on finding for better and more efficient methods to inspect their equipment and structures. In this study, it focused on the development the real-time non-contract monitoring system as an efficient tool for the experimental study of weld defects based on the relationship between the measured voltage and input parameters.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.7
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• pp.491-499
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• 2007

An architectural means of optimal daylight distribution is by using so-called light shelf systems, horizontal shading and redirecting devices. The overall performance of the daylighting system can be improved by the incorporation with electric lighting control devices. This paper aims to exemplify the benefit of daylighting in term of economic consideration. In such a case a reasonable technique to compare system costs is by life-cycle costing. Stated simply, a life-cycle cost represents the total cost of a system over its entire life cycle, that is, the sum of first cost and all future costs. Four different electric lighting system designs are proposed and a lighting control system that is continuously operating according to the level of daylight in the space has been adapted. The result shows clearly that although denser layout of lighting fixtures might be more effective to interface to the level of daylight ceaselessly changeable, its economic benefit may not meet the expected criterion the reason of increased initial investment and maintenance cost for the fixtures and control devices.