• Title, Summary, Keyword: RCM

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Experimental Study on Peak-Pressure Variation Due to Compression by Using RCM (급속 압축장치(RCM)의 압축 조건에 따른 최대 압력 변화에 관한 실험적 연구)

  • Kim, Hye-Min;Kim, Hak-Young;Baek, Seung-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.2
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    • pp.197-204
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    • 2011
  • RCM is used to clarify the complex phenomena of engine combustion. In order to describe engine combustion, several significant experimental studies are considered. Prediction of the peak pressure is very important since it has a significant influence on engine combustion. In addition, peak-temperature variation can be calculated from the measured peak pressure by using the fundamental thermodynamic relation. When the RCM is in operation, heat transfer occurs through the cylinder wall. Because of this phenomenon, it is difficult to determine the peak pressure without employing the case by case experimental method. The goal of this study is to evaluate the peak pressure analytically. We conduct an experiment to confirm the relationship between the peak pressure and some parameters. Using the results of the peak pressure variation experiment, we develop a general equation that be used to calculate the peak pressure as a function of operation time and compression ratio.

A Study to the Plan for Development of Maintenance applied RCM (RCM을 적용한 유지보수 시스템 구축에 관한 연구)

  • Oh, Ahn-Sup;Lee, Hun-Il;Shin, Kook-Ho;Shin, Kun-Young;Jang, Seong-Tae
    • Proceedings of the KSR Conference
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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.

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Effects of IAA, IBA, and Media on Growth and Saikosaponin Biosynthesis in Bupleurum falcatum Hairy Root Culture (시호 모상근 배양에서 생장과 시호 사포닌 생합성에 미치는 배지와 IAA 및 IBA의 영향)

  • Ahn, Jun Cheul;Kim, Eung Sik;Lee, Hyun Jin;Hwang, Baik
    • Korean Journal of Plant Tissue Culture
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    • v.26 no.3
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    • pp.171-175
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    • 1999
  • We examined the effects of various basal media and exogenous auxins on the growth and saikosaponin production in hairy root cultures of Bupleurum falcatum. Of the various media tested, 2RCM medium was superior for growth and saikosaponin content, in which saikosaponin a, c, and d was produced, however MS medium was resulted in extremely low level in saikosaponin production. By the treatment of 0.5 mg/L IBA the growth rate was increased by about 60% in 2RCM medium, whereas both IAA and IBA showed a potent inhibition effect in saikosaponin biosynthesis by the treatment of 0.01 mg/L~5mg/L.

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Climate Change effect on Rainfall Frequency analysis using high resolution RCM Data (고해상도의 RCM 자료를 이용한 기후변화가 강우빈도 분석에 미치는 영향)

  • Kim, Byung-Sik;Kim, Bo-Kyung;Kwon, Hyun-Ha;Yoon, Seok-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • pp.224-228
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    • 2008
  • 2007년 세계경제포럼(WEF)은 우리가 직면한 최우선 해결과제로 기후변화를 언급하였다. 최저 기온 상승과 가뭄 영향 지역 확대, 폭염일수와 지역적 홍수 위험 증가 등 각종 이상기상이 야기하는 피해 확대에 대한 예상과 우려 때문이다(IPCC, 2007). 세계적으로 고온극한과 호우빈도 증가, 태풍 세기가 강화될 것으로 전망되고 있으며(IPCC, 2007), 국내의 경우 겨울철 한파 감소와 대설 피해 증가, 여름철 집중호우의 강도 심화, 가을철 초대형 태풍 발생으로 인한 피해 가능성이 예측 되고 있다(기상연구소, 2007). 현재, 이러한 현상들을 가시화하고 대처방안을 마련하기 위한 일환으로 기후변화 시나리오(GCM)가 작성되어 연구에 이용되고 있다. 그러나 GCM의 경우, 공간적 해상도가 낮아 지형학적 특성 등을 충분히 반영하지 못하는 단점이 있어 최근에는 공간 해상도가 GCM보다 높은 RCM(Regional Climate Model, 지역기후모델)자료를 적용한 연구도 진행되고 있다. 본 논문에서는 SRES A2 온난화가스시나리오 기반의 기상청 RegCM3 RCM($27km{\times}27km$)로 부터 일(daily)단위 자료를 각각 모의하여 비교하고, BLRPM을 이용하여 일(daily)단위 자료를 시(hourly)단위로 분해(disaggregation)하였다. 그리고 이들을 이용하여 지속기간별 확률강우량을 산정하여 미래 기후변화가 극한 강우에 미치는 영향을 평가하였다.

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Analysis of Regional Climate Model For Climate Change Impacts on Water Resources (기후변화에 따른 수자원 영향 평가를 위한 Regional Climate Model에 의한 강수 자료의 특성 분석)

  • Kwon, Hyun-Ha;Kim, Byung-Sik;Yoon, Seok-Young;Kim, Bo-Kyung
    • Proceedings of the Korea Water Resources Association Conference
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    • pp.1018-1022
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    • 2008
  • 2007년 Intergovernmental Panel on Climate Change(IPCC) 4차보고서 이후로 지구 온난화에 대한 다양한 부분에 영향 분석 연구가 더욱 활발하게 진행되고 있으며, 그 가운데 수자원 즉 육상의 물 순환은 인간 활동과 생태계 전반에 대한 직접 영향으로 인해 기후변화 정책 수립 시 그 중요성이 더욱 부각되고 있다. 현재까지, 많은 연구에 있어서 Global Circulation Model (GCM)을 직접 축소기법을 이용한 후 이를 수문 모형에 입력하여 수자원 영향 분석을 실시해오고 있다. 국외를 중심으로 기존 GCM보다 해상도가 높은 Regional Climate Model(RCM)을 이용한 분석이 일부 시행되고 있으나, 국내에서는 자료의 가용 여부 및 적용성의 검토가 아직 미비한 실정이다. 이러한 관점에서 본 연구에서는 27km의 해상도를 갖는 기상청 RegCM3 RCM에서 도출된 10일 간격 기후변화 SRES 시나리오 자료에 대한 적합성을 평가하고자 한다. 적합성을 평가 하기위해서 국내 주요지점에 근접한 격자자료를 RCM으로부터 추출하고 이에 대한 수문학적 특성치 분석, 저빈도 분석(low frequency analysis), 극치사상의 분포형태 등을 실측 강수자료와 다양한 형태로 비교 검토하여 RCM 자료의 적합성을 평가하였다.

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Constructing the Maintenance Management Framework for KTX trains using RCM (RCM을 이용한 한국 고속철도차량의 유지보수체계 구축)

  • 오석문;강길현;김성권;유경종;최석중
    • Proceedings of the KSR Conference
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    • pp.53-60
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    • 2002
  • This paper introduces KTX RCM(Reliability-Centered Maintenance) project which is for development of a decision making support system on the KTX maintenance framework. The functionality of the system is composed of ( i ) Fundamental Data Management, ( ⅱ ) Maintenance Goal Management, ( ⅲ ) Maintenance Program Management, ( ⅳ ) Cost-Effect Analysis, ( v ) Parameter Management. This system may improve existing maintenance Management procedure for rolling stock of KNR.

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An applicable RCM method for Track circuit equipment of AREX's Signalling System (공항철도 궤도회로장치에 대한 RCM 적용 방안)

  • Song, Mi-Ok;Lim, Sung-Soo;Lee, Chang-Hwan;Park, Seung-Keun
    • Proceedings of the KSR Conference
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    • pp.1126-1131
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    • 2008
  • In this paper we introduce an applicable RCM(Reliability centered maintenance) method for Track circuit equipment of AREX's Signalling System. AREX computerize all the process of FRACAS(Failure Reporting, Analysis and Corrective Action System)) by the Facility Management System of Integrated Information System. These datum were analysed and reproduced as the RAMS index value which can be used by maintenance staff for optimizing the maintenance method of the System.

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A Study on Reliability Centered Maintenance (통합신뢰성 경영에서 보전에 중점을 둔 신뢰성에 관한 연구)

  • Kim, Hwan-Joong
    • Journal of Applied Reliability
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    • v.3 no.1
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    • pp.73-82
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    • 2003
  • Reliability Centered Maintenance(RCM) was initially developed for the commercial aviation industry in the late 1960s and now is equally applicable to a variety of equipment other than aircraft. RCM is a method for establishing a preventive maintenance program which will efficiently and effectively allow the achivement of the the required safety and availability levels of equipment and structures. RCM provides for the use of a decision logic tree to identify applicable and effective preventive maintenance requirements for equipment and structures according to the safety, maintenance requirements for equipment and structures according to the safety, operational and economic consequences of identifiable failures, and the degradation mechanism, reponsible for the those failures. The end result of working through the decision logic is a judgement as to the necessity of performing a maintenance task. In this paper, we provide guiding principles based on IEC 60300-3-11 for RCM analysis methods and operational method of structure and equipment.

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Hardware-Oriented Reliability Centered Maintenance for the Diesel Generators of Wolsong Unit 1

  • Bae, Sang-Min;Park, Jin-Hee;Kim, Tae-Woon;Lee, Yoon-Kee;Song, Jin-Bae
    • Proceedings of the Korean Nuclear Society Conference
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    • pp.587-591
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    • 1997
  • The DGs (Diesel Generators) in NPP (Nuclear Power Plant) has been used for the emergency electric power source to shut down the nuclear reactor safely in case of station blackout. The RCM (Reliability Centered Maintenance) has been applied to DGs for increasing the safety of NPP. The structured defects of DG were not remedied by the improvement of maintenance method. As the first stage of RCM, to find the structured defects, its failure modes were searched and analyzed through the ten year maintenance information. The structured defects such as the air compressor, the lubricating oil pressure, and the insufficient load were the root causes of main failures. The air reservoir reinstallation, the lubricating oil tube modification, the load bank installation, and the qualitative instrumentation were the solutions for the hardware oriented RCM of DGs. There remains the software oriented RCM such as the rejection of useless maintenance, the preventive maintenance, the database of maintenance information, and the predictive maintenance.

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