• 산업경영시스템학회지
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• 제14권24호
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• pp.207-219
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• 1991

We studied performance evaluation methods for each cause by using a benchmark and also researched performance measurement models which based on CAPM. In this study, we analyzed the beneficiary certificate of stock type of three large domestic investment trust company. The purpose of this paper is improving the efficiency of investment maintenance and the operating the ability of fund operator by analyzing the contribution of the rate of return on investment and the cause of operating performance. We applied this study to the increasing aspect of stock price(Jan. 1988-April. 1999) as well as the decreasing aspect of stock price(April, 1989-July. 1990).

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1306-1311
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• 2006

Most of design parameters of Railway Structures are determined by the serviceability requirements, rather than the structural safety requirements. The serviceability requirements come from Ensuring of Running Safety and Ride Comfort of Train, Reduction of Track Maintenance Work Track-Bridge Interaction should be considered in the design of railway structures. In this study, a numerical method which precisely evaluate an axial force in rail and a rail expansion and contraction when turnout exist in succession on a CWR on a ballasted or on a ballastless track of bridge is developed. From the parameter studies using the developed method, additional stress of stock rail almost 25% is generated due to stock and lead rail interaction, even embankment not bridge. In case of ballasted track, additional stress of stock rail on bridge is very greater than on embankment, and therefore require detailed review in bridge design with turnout. Stresses of turnout rails on bridge are very sensitive according to the installed positions. In case of ballastless track, Stresses of turnout rails are similar as those of normal track

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.907-914
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• 2011

It has used for Rolling Stock Maintenance a number of maintenance system applied RCM in Railway(Korea Railroad Corporation, Seoul Metro, Korail Airport Railroad Corporation, etc) so far. Some institutions has been using develop Computational System including reliability process. A majority of the system has computerized maintenance work, but it is shown that developed focus on administrator and developer not user. SMRT(Seoul Metropolitan Rapid Transit Corporation) has developed computational system for maintenance in the '90s and saved many data about Maintenance Historical Data. However, this system reached the limits application of this data. Maintenance of computer systems is managed directly by the field staff and to introduce Reliability-centered maintenance SMRT was continually reviewed system development trends and supplement the existing system. To successfully operate RCM program should be gained full support in the whole company and field communicate, secure a reliable data from field and the most important take a patience. Our corporation will operate and develop successful RCM thorough review of these problems in the future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.408-413
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• 2002

From the moment that electricity is applied to a relay, a wheel turned, or a valve opened, the process leading to the need for maintenance begins, The uninitiated will tell you that the Maintenance man is someone who repairs something when it has gone wrong. Unfortunately, in any large engineering concern, such as a railway, it is not possible to work on the principle that only when something breaks down should it get any attention. The failure of one contact, diode or bearing could well stop not only the assembly of which it is a part, but the flow line or process, with loss of revenue, and clientele, and often with effects on the safety of both staff and the traveling public. So, we have to establish the reliable and cost-effective maintenance system to resolve these problems.

• Journal of Animal Science and Technology
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• 제60권4호
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• pp.7.1-7.5
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• 2018

Background: Mice are widely accepted research models of great clinical significance. Maintenance of laboratory mice breed is an essential aspect for performing research activities in various fields of science. Infanticide is one of the prominent causes of litter loss during maintenance of laboratory mice stock. The present study is an effort to monitor the effect of change in ambient temperature of female mice below the normal range on cannibalism and infanticide during early postparturition phase. Adult female Swiss albino mice have been divided into two groups of control and treatment. On the day of litter group one was maintained under controlled temperature conditions (minimum $20^{\circ}C$ to maximum $23^{\circ}C$) throughout, while female mice belong to group two have been exposed to variation of room temperature (maximum $15^{\circ}C$ to minimum $10^{\circ}C$ for two nights and one day) until 36 h postparturition. Results: The effects of temperature changes were observed on the infanticide behaviour of dams along with the survival of pups in early postparturition phase till 36 h after delivery. The significant statistical difference (P < 0.05) was reported in infanticide behaviour of dams when control and treatment group was compared. It is observed that decrement in surrounding temperature promotes decrement in the ambient body temperature of dams during early postparturition. It is proposed that alteration of hypothalamic homeostasis due to temperature change induces cannibalism and infanticide behaviour. Lack of thermoregulation during early postparturition creates the sense of insecurity, in-satiety, anxiety and stress. Conclusions: Authors strongly recommend the maintenance of body and surrounding temperature to prevent infanticidal behaviour and cannibalism within Swiss albino mice population. Further investigations are advisable to authenticate the active behavioural and biochemical pathway behind the phenomena.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.897-901
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• 2005

21 century as the knowledge information anger society now our society industry of all fields the rolling stock maintenance conservative standardization enterprise where information anger is being turning out construction Ministry of Transportation supported with continuous development of the supply section substitution quantity information processing system which the information highway is quick and the Korean railroad technical research worker propelled the enterprise as the subjective agency, it contracted this for a vehicle field information anger system construction in link of the enterprise our construction and an agreement, information technique composed the consortium t9day and it propelled a system codevelopment. The SMSC who is a front-runner of Maj loach city railroad operation agency to 'here business relates with a vehicle field maintenance conservativeness an immediacy operation and generally and information anger it will plan it will integrate it will own jointly and business efficiency and in the dictionary an obstacle occurrence electromotive car maintenance conservative information and it will improve only maintenance conservativeness of preventive maintenance of the electromotive car it knows it will prevent to construct the maintenance conservative system of the preventive maintenance, it applied the RIMS project to sleep.

• 한국국방경영분석학회지
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• 제8권2호
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• pp.31-35
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• 1982

Recently, Park [1] proposed an algorithm for the optimum spare-part stock level in an (S-1, S) inventory system for small fleet. This paper reports validative GPSS simulation results and numerical experiences with the algorithm.

• 대한건축학회논문집:구조계
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• 제35권12호
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• pp.181-188
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• 2019

The maintenance of school building is pivotal issue. However, it is difficult to obtain basic analysis data for LCC(Lifecycle Cost) analysis and maintenance planning of school building. Therefore, this study proposed System Dynamics(SD) techniques to make maintenance decisions for school building. The interaction between the major parameters related to the aging of a building, maintenance activities, and cost were expressed in Causal Loop Diagram. Based on this, the formula for the relationship between causal maps was defined and converted to Stock and Flow Diagram. Through the completed SD model the 50-year plan of 214 educational building were tested by considered in account budget, maintainability, and budget allocation opinions. As a result, the integrated SD model demonstrated that it can support strategic decision making by identifying the status class and LCC behavior of school buildings by scenario. According to the scenario analysis, the rehabilitation action of preventive maintenance that primarily repairs the buildings in condition grade C showed the best performance improvement effect relative to the cost. Therefore, if the proposed SD model is expanded to consider the effects of other educational policies, the crucial performance improvement budget can be estimated in the long-term perspective.

• The Journal of Asian Finance, Economics and Business
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• 제9권10호
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• pp.115-127
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• 2022

The study's goal was to investigate the levels of employee loyalty (EL) in two Thai railway rolling stock maintenance (RRSM) companies. Simple random sampling was used to obtain a final sample of 118 individuals from October 2021 through December 2021. The research instrument was a questionnaire with an expert IOC value between 0.67 to 1.00 and a questionnaire reliability Alpha (𝛼) average value of 0.82. Descriptive statistics included the mean and standard deviation (SD). SPSS for Windows Version 21 and Multiple Regression Analysis (MRA) was used for the analysis. Results showed that the 118 employee's overall perceptions of their RRSM employers' motivating factors, human resource management, satisfaction, and loyalty were high. HRM's performance evaluation had the most significant overall influence on EL. Moreover, from the analysis of the five EL questionnaire items, the most influential item was the employee's income as a contributing factor to their EL. This was followed by the suitability of their work. Also, it seems the employees had a high level of loyalty to their firms even if a better offer of more money was made. They also indicated a high level of pride in their respective firms.

• 품질경영학회지
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• 제17권1호
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• pp.1-10
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• 1989

In general, the characteristics of components which consist of multi-component system can not be the same. This paper proposes a maintenance model of multi-component system considering the characteristics of each component. In this paper, multi-component system is divided into three components-critical unit, major unit and minor unit, respectively. This paper determines the optimal replacement time of the system which minimizes total maintenance cost, optimal replacement period of major unit and initial stock quantity of minor unit within this optimal replacement time. Numerical examples are shown when the failure times of each unit have gamma distribution.