• 대한안전경영과학회지
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• 제16권2호
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• pp.31-42
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• 2014

As weapon systems become complex in terms of the scale and functionality, the required time to complete the test and evaluation (T&E) process is inevitably getting longer. However, nowadays the reduction of T&E period becomes one of the core targets in the weapon systems acquisition programs. This is because the reduced time for T&E process can yield the reduction of defense budget and also faster deployment of the weapon systems, thereby having a competitive edge over rival countries. On the other hand, in weapon systems development the management of reliability, availability, maintainability and safety (RAMS), and risk is considered important to keep competitiveness and thus has been carried out separately. Thus, the objective of this paper is to study on improving the T&E process by integrating the RAMS and risk management process in it. To do so, the related processes are analyzed and modeled first. Then an integrated process model is developed. The resulting model is equipped with the traceability among the data and interfaces that are generated from the T&E and RAMS/risk processes. As a case study, the model developed is applied in tanks development. The effective use of the traceability is expected to reduce the time and cost required to complete T&E process.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.226-238
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• 2011

RAMS (Reliability, Availability, Maintainability, Safety) study has received far less rigorous analysis in the system performance and integration level, and RCM (Reliability Centered Maintenance) research has been studying to improve the maintenance efficiency in the operational steps based on collected data of real operational cases. This paper analyzes the basic concepts based on KS X ISO/IEC 15288 system life-cycle process in the whole system for the light rail transit construction, and the research suggests an approach to the management process of the applicable main tasks. The paper "Management Process Study to RAMS Application of Light Rail Transit System" introduces Airport Rail cases and guidelines by using RAMS which is the major role in the system engineering technical process of ISO/IEC 15288 (International Organization for Standardization/International Electrotechnical Commission 15288) to apply RAMS in domestic light rail transit efficiently, the aim of this study is to broaden of understanding RAMS.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.2038-2043
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• 2009

RAMS(Reliability, Availability, Maintainability, Safety) analyses are particularly important in the railway engineering sector and are increasingly required the specialized procedures. The RAMS analysis is performed to meet the high safety and quality standards. The RAMS standards were established in 1990s. EN 50126 of CENELEC, and IEC 62278 provide railway authorities and railway company with a procedure which will enable the implementation of a consistent approach to the management of RAMS. IEC 62278 will be often referred to in the field of railway system. This paper represents the RAMS procedure to apply to the EMU (Electrical Multiple Unit) based on the referenced RAMS standards.

• 한국안전학회지
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• 제35권1호
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• pp.18-24
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• 2020

This research conducted an the failure analysis was performed based on the failure and operation data for Seven years using the Reliability, Availability, Maintainability, and Safety(RAMS) constructed at the operation stage after the opening of the D urban railway. therefore, the risk priority was selected for failure frequency component within the door system that showed high failure. Finally, the goal was to suggest ways to improve the door system. For this purpose, the analysis of thermal characteristics of failed components such as Door Control Unit(DCU) in the door system based on the Seven-year failure analysis data of RAMS was performed. These results were applied to the main component exchange cycle of the door unit, the mean time between failure(MTBF) and mean kilometer between failure(MKBF) values of RAMS increased by 26% in 2017-2018 when the improvement measures were taken, and the MTBF value of DCU was 300,000 hours, which was a 57% improvement in reliability. The results of this thesis identify potential enhancements in reliability and improvements in maintenance of the door system that, if implemented, would contribute to train safety and reduce instances of failure in the future.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2001년도 정기학술대회
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• pp.227-229
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• 2001

The components of dependability are reliability, availability, maintainability, safety. The dependability thus often designated in terms of RAMS. A guide to the appropriate selection applicable standards on test conditions and statistical analysis is suggested. It includes a general guide to planning, performing and analysing data from reliability tests. The environmental and operational conditions available as IEC standards are referred.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권4호
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• pp.168-176
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• 2001

In this paper, we develop a dual-duplex system which detects a fault by hardware comparator and switches to hot standby redundancy. This system is designed on the basis of MC68000 and can be used in VMEbus. To improve reliability, the dual-duplex system is designed in dual modular redundancy. The failure rate of electrical element is calculated in MILSPEC-217F, and the system RAMS(Reliability, Availiability, Maintainability and Safety) and MTTF(Mean Time to Failure) are evaluated by Markov modeling method. As the evaluation result shows improved reliability, it can be used as a component hardware for a highly reliable control system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.206-212
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• 2004

This paper is application of System Assurance(SA) for the rolling stock. As railway systems become more complex, design teams are increasingly under pressure to deliver, design solutions, which integrate both technical and Systems Assurance(SA). Systems Assurance is the application of management methods and analysis techniques to ensure that a design meets Reliability, Availability, Maintainability and Safety (RAMS) criteria. It should be clearly understood that the intent of System Assurance is not just to provide analytical techniques as a metric on performance, but more importantly it should provide a management tool with which to co-ordinate and assure the whole design. System Assurance encompasses the ongoing requirement to consider safety, and RAM through each stage of a Project, from feasibility study through to commissioning and operation. If System Assurance is undertaken properly at feasibility study at the design stages of a Project, the benefits of such analyses can be significant in identifying potential problems early enough for action to be taken before manufacture or installation. At commissioning, RAMS demonstration activities are undertaken to validate the predictive and analytical techniques undertaken during the design.

• 한국철도학회논문집
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• 제14권6호
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• pp.515-525
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• 2011

도시형 자기부상열차 실용화사업에 적용된 유도무선루프방식 열차제어시스템에 대하여 최상위 레벨에서 전체 시스템에 대한 시스템 분류, 기능 분석을 시행하고 차상신호설비, 지상신호설비로 나누어 신뢰도, 가용도, 유지보수도 및 안전도를 수식을 통하여 분석한 결과를 제시하였다. RAM 분석은 신뢰도 블록도(RBD)를 각 장치별로 적용하여 시스템 서비스 가용도를 산출하였고, 안전도 분석은 PHA(예비위험원 분석), FMEA (고장모드영향분석), HAZOP을 통한 각각의 정상사상(Top Event)의 FTA(고장트리분석)을 시행하고 그 결과를 제시하여 RAMS 목표 값에 도달함을 수식을 통하여 증명하였다.

• 한국철도학회논문집
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• 제8권3호
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• pp.286-292
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• 2005

In this paper, we introduce IEC 60300(Dependability program management) into urban transit system, and propose effective method to apply IEC 60300 to Subway Corporation. The dependability is the collective term used to describe the availability performance and its influencing factors such as reliability performance, maintainability performance and maintenance support performance. A dependability program covers all phases of a system's life cycle from planning to operation and possibly disposal, and is composed of program elements divided into tasks.

• Structural Monitoring and Maintenance
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• 제5권1호
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• pp.79-92
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• 2018

The evaluation theory of reliability, availability, maintainability and safety (RAMS) as a mature theory of state evaluation in the railway engineering, can be well used to the evaluation, management, and maintenance of complicated structure like the long-span bridge structures on the high-speed railway. Taking a typical steel-truss arch bridge on the Beijing-Shanghai high-speed railway, the Nanjing Dashengguan Yangtze River Bridge, this paper developed a new method of state evaluation for the existing steel-truss arch high-speed railway bridge. The evaluation framework of serving state for the bridge structure is presented based on the RAMS theory. According to the failure-risk, safety/availability, maintenance of bridge members, the state evaluation method of each monitoring item is presented. The weights of the performance items and the monitoring items in all evaluation levels are obtained using the analytic hierarchy process. Finally, the comprehensive serving state of bridge structure is hierarchical evaluated.