• 한국군사과학기술학회지
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• 제13권1호
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• pp.67-76
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• 2010

RAM(Reliability, Availability, Maintainability) characteristics of weapon system is a part of Required Operational Capability, must be reasonable and achievable. In this study, we studied the criteria, important factors to establish RAM requirement and reviewed the current process. Then we propose the new process and method to establish the reasonable and achievable RAM requirement by BCS(Baseline Comparison System) model.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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• pp.505-510
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• 1996

A simple model for RAM (Reliability, Availability and Maintainability) analysis and its computer code are developed for application to DUPIC fuel fabrication system. The approach is obtained by linking the allocation model (top-down method) to bottom-up method for RAM analysis. As a result, the availability requirement of subsystem, as well as the buffer storage requirement between processes, are evaluated for the DUPIC facility..

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2001년도 정기학술대회
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• pp.503-511
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• 2001

신규 개발되는 기동장비의 RAM-D 요구조건 설정방법에 관하여 기동 무기체계의 대표적 장비인 전차를 대상으로 연구하였으며, 사용자의 장비운용에 대한 요구 가용 능력 및 운용유지 조건을 고려한 RAM-D 요구조건 설정절차 및 분석 모델을 개발하였다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권2호
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• pp.150-158
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• 2017

Purpose: The RAM objective is a very important factor that has a great effect on the improvement of the operation ration during the operation maintenance and the reduction of the life cycle cost. It is used as a design criterion during the system development, and its sufficiency should be evaluated during its test evaluation. Method: This study analyzed the cases related to RAM objective setting and suggested the improvement measures. Result: The base data for RAM objective is OMS/MP, which needs to be drawn up under the supervision of the requirement military, and a high-accuracy operating availability should be set through ALDT calculation which reflects the military logistics support environment. In addition, data collection necessary for RAM objective and RAM analysis should be made by supplementing the input data of DELIIS. Conclusion: This study suggests improvement of RAM objective considering for the weapon system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.191-198
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• 2009

There are almost no studies on verification of requirements for high speed rolling stocks by means of RAM goals and on setting RAM goals by means of verification on practical reliability, availability and maintainability for high speed rolling stocks though they are covered in specification of an order that RAM goals asked of rolling stocks are shown for gaining high quality of them and availability when they are in operation. This study is for estimating number of high speed train-sets that would be supplementarily placed an order through verification of RAM goals of a project for the introduction of KTX-II 100 cars. It verify that optimized requirements for high speed rolling stocks by relatively comparison with between requirements for train-sets through setting RAM goals and requirements for train-sets through analysis of prospects for management balance with high speed rolling stocks.

• Asian-Australasian Journal of Animal Sciences
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• 제26권9호
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• pp.1282-1288
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• 2013

A comparative slaughter trial was conducted to estimate the phosphorus (P) requirement for maintenance and growth of crossbred lambs of Dorper with a Chinese indigenous sheep breed, thin-tailed Han sheep. Thirty-five Dorper${\times}$thin-tailed Han crossbred, noncastrated ram lambs ($20.3{\pm}0.22kg$ of shrunk body weight (SBW)) were used. Seven lambs were randomly chosen and slaughtered at 20 kg SBW as the baseline group for measuring initial body composition. Another seven lambs were also randomly chosen and offered a pelleted mixed diet for ad libitum intake and slaughtered at 28 kg SBW. The remaining 21 sheep were randomly divided into 3 groups with 7 sheep each and subject to the same diet of either 70 or 40% of ad libitum intake. The 3 groups were slaughtered when the sheep fed ad libitum reached 35 kg of SBW. Body P contents were determined after slaughter. The results showed that the net P requirement for maintenance was 30.0 mg/kg of empty body weight (EBW) or 23.4 mg/kg body weight (BW), and the P requirement for growth decreased from 5.3 to 5.0 g/kg of EBW gain as the lamb grew from 20 to 35 kg. The net P requirement for growth of Dorper${\times}$thin-tailed Han crossbred ram lambs was lower than that of sheep adopted by the American nutritional system.

• 한국신뢰성학회지:신뢰성응용연구
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• 제15권4호
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• pp.282-288
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• 2015

Purpose : The purpose of this study is to compare the RAM (reliability, availability and maintainability) value in the acquisition phase with operational period for air weapon systems. The objective is to determine if the value of RAM is sufficient in the field, and look for any difference from the target value to some extent. Methods : For a case study, the ${\bigcirc}{\bigcirc}$ training aircraft is selected. Data from the two acquisition sources are utilized. One is the operational data in domestic aircraft through research and development, and the other is the data from imported aircraft. The two different sources were collected independently and distinctly. Results : According to the analysis, the domestic aircraft shows high deviation in RAM value compare to the imported systems. This is due to the effort of continuous reliability improvement. In the aspect of maintainability, the result shows a slight deviation, and the availability meets the requirement. Conclusion : The results of this study can be used in finding a way that can be effectively applied to the sustainability in the weapon system. If the RAM performance is significantly lower than the target value, then it is necessary to improve the design activities so that they can achieve the RAM target value.

• 한국철도학회논문집
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• 제11권4호
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• pp.371-377
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• 2008

철도가 친환경 교통수단으로 각광을 받으면서 세계적으로 많은 고속철도와 도시간, 도시 철도가 건설되고 리모델링되고 있다. 이 추세에 맞추어 철도 RAMS는 2002년도에 국제규격인 IEC 62278에 포함되었다. 국내 철도시장의 RAMS 활동도 이 국제적 추세에 맞추어 활발해지고 있다. 그러나 IEC 62278은 RAMS 요구조건이 구매사양에 포함될 때 전체적인 가이드라인으로는 사용될 수 있지만 신뢰성목표가 어떻게 설정되어야 하는가와 같은 구체적인 방법을 포함하고 있지는 않다. 이것은 RAMS 요구조건은 특정한 철도 조건에 맞게 설정되어야만 하기 때문이다. 철도 RAMS 특성값의 의미를 완전히 이해하고, 이 특성값들을 특정한 철도시스템과 환경조건에 맞게 적용하는 것이 특히 정량적 요구조건에 대해서는 더욱 필수적이다. 이 연구에서는 철도차량의 정량적 RAMS 요구조건의 개발에 적용 가능한 RAMS 특성값들의 의미와 특성을 기술한다. 그리고 정량적 RAMS요구조건의 개발에 적합하게 IEC62278의 RAMS의 기본개념과 고장 개념을 수정하여 제안하였다.

• 한국산업융합학회 논문집
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• 제26권5호
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• pp.855-866
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• 2023

With the rapid advancement and sophistication of defense weapon systems, the government, military, and the defense industry have conducted various innovative attempts to improve the efficiency of post-logistics support(PLS). The Ministry of Defense has mandated RAM-C(Reliability, Availability, and Maintainability-Cost) analysis as a requirement according to revised Total Life Cycle System Management Code of Practice in May 2022. Especially, for the project budget forecast of new PBL(Performance Based Logistics) business contacts, RAM-C is recognized as an obligatory factor. However, relevant entities have not officially provided guidelines or manuals for RAM-C analysis, and each defense contractor conducts RAM-C analysis with different standards and methods to win PBL-related business contract. Hence, this study aims to contribute to the generalization of the analysis procedure by presenting a cost analysis case based on RAM-C for the supply of military depot maintenance PBL project. This study presents formulas and procedures to determine requirements of military depot maintenance PBL project for repair parts supply. Moreover, a sensitivity analysis was conducted to find the optimal cost/utilization ratio. During the process, a correlation was found between supply delay and total cost of ownership as well as between cost variability and utilization rate. The analysis results are expected to provide an important basis for the conceptualization of the cost analysis for the supply of military depot maintenance PBL project and are capable of proposing the optimal utilization rate in relation to cost.

• 전기학회논문지
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• 제65권7호
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• pp.1161-1168
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• 2016

Battery energy storage system(BESS) attract the attention of the power system operators with its fast response to a disturbance in spite of its limited energy capacity. This paper proposes the operating method of BESS for following the Automatic Generation Control(AGC) frequency control which is centrally distributed by a system operator. As BESS needs to just meet the control requirement from the system operator, it should be able to properly manage the state of charge(SOC) of BESS to be available to control signal. For doing these, the proposed method distributes the control requirement to available batteries in proportion to its SOC. In addition, unavailable batteries are controlled to recover the SOC to an appropriate range, and the recovering power is supplied by available batteries meeting the control requirement. Moreover, the proposed method manages the efficiency of power conversion system (PCS) by limiting the number of PCS to be assigned for the low control requirement. Finally, the case studies are carried out to verify the effectiveness of proposed strategy.