• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1541-1544
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• 2003

In this study, embodying reliability block diagram based on the web and reliability analysis technology are developed. RBD(reliability Block Diagram) represents the functional relation between elements in any product. Among relations between elements. there are serial, parallel, bridge, and stand by, etc. Advantages of developed system are integrated datum about reliability (NPRD, EPRD, MIL-HDBK 217F, NSWC. OREDA. Bellcore, and domestic institutes & companies datum). graphic user interface for convenience, and the various service analyzes the failure history data of parts.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.6
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• pp.629-633
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• 2011

Recently, systems such as aircraft, trains and ships have become larger more complex. Therefore, the reliability calculation of these systems is more difficult. This paper presents a reliability calculation algorithm for a complex system with a solution that is difficult to analyze. When the system has a very complex structure, it is very difficult to find an analytical solution. In this case, we can assess system reliability using the failure enumeration method of the reliability path. In this research, we represent the reliability block diagram by an adjacent matrix and define the reliability path. We can find any system status by the failure enumeration of the reliability path, and thus we can calculate any kind of system reliability through this process. This result can be applied to RCM (Reliability-Centered Maintenance) and reliability information-management systems, in which the system reliability is composed of the reliabilities of individual parts.

• Journal of the Korea Society for Simulation
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• v.22 no.4
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• pp.109-118
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• 2013

This paper adopts the system configuration to assess the reliability instead of making a fault tree (FT), which is a traditional method to analyze reliability of a certain system; this is the reliability block diagram (RBD) method. The RBD method is a graphical presentation of a system diagram connecting the subsystems of components according to their functions or reliability relationships. The equipment model for the reliability simulation is modeled based on the discrete event system specification (DEVS) formalism. In order to make various alternatives of target system, this paper also adopts the system entity structure (SES), an ontological framework that hierarchically represents the elements of a system and their relationships. To enhance the calculation time of reliability analysis, GPU-based accelerations are adopted to the reliability simulation.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.281-285
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• 2015

Electrical energy supply interruption degrades reliability of power supply as well as social costs and economic loss. It is important to assess the reliability of the power system. Nowadays IEC61850 based substation automation system(SAS) has been developed for an updating of automation and interoperability. In this study, three kinds of reliability block diagram(RBD) were proposed to examine of network availability of the three types SAS. And reliability and unreliability of the SAS was formulated using the RBD. Finally, while varying the value of reliability and unreliability, the reliability and the unreliability of the overall system were evaluated.

• Journal of the Korea Safety Management & Science
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• v.13 no.3
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• pp.45-53
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• 2011

The research proposes seven elimination rules of redundant gates and blocks in Fault Tree Analysis (FTA) and Reliability Block Diagram (RBD). The computational complexity of cut sets and path sets is NP-hard. In order to reduce the complexity of Minimal Cut Set (MCS) and Minimal Path Set (MPS), the paper classifies generation algorithms. Moreover, the study develops six implementation steps which reflect structural importance (SI) and reliability importance (RI) from Reliability Centered Maintenance (RCM) that a priority of using the functional logic among components is to reduce (improve) the system unavailability (or availability). The proposed steps include efficient generation of state structure function by Rare Event Enumeration (REA). Effective use of importance measures, such as SI and ill measures, is presented based on the number and the size of MCS and MPS which is generated from the reference[5] of this paper. In addition, numerical examples are presented for practitioners to obtain the comprehensive understanding of six steps that is proposed in this research.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.527-532
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• 2007

In this paper, we suggest those two design plans for power supply method of Hot Standby Sparing System; one is the plan using MTBF based on Constant Failure Rate, and the plan using Reliability Function is the other. Traditionally, RBD (Reliability Block Diagram) is used for reliability prediction which is required to meet any requirements before system operation. However, the system that has redundancy, such as Hot Standby Sparing System, Is not suitable for system reliability modeling using combination model, such as RBD. In this paper, therefore, we demonstrate that for redundancy controller, redundancy modeling design toward fault occurrence design is more effective to build up a system with higher reliability and achieve the effectiveness of loss cost due to maintenance and failure occurred in operation, rather than combinational modeling design.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.6
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• pp.595-601
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• 2009

A flight control system for high reliability consists of complicated redundant structures. This redundancy can improve fault tolerant characteristics of system. So, a system manager is able to choose a suitable structure using analyzed quantitative data of various redundant structures. In this paper, we analyzed redundant characteristics and reliability. We defined necessary mathematical model for analysis tool. Then we compose a reliability block diagram analysis tool applying such defined analysis model using Simulink blocks. Finally we verified the analysis tool using a commercial tool.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.12
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• pp.1193-1200
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• 2008

The procedure of design for reliability which consists of reliability analysis and Failure Modes and Effects Analysis(FMEA) is established and reliability assesment is performed for the nano-satellite air-launching rocket, Mirinae II. By means of using the reliability analysis result, the feasibility to insert the Mirinae II to the target orbit for given mission time under operating environment is assessed. During the reliability analysis process, the system is categorized by Work Breakdown Structure(WBS), and reliability structure is defined by both Reliability Block Diagram(RBD) and schematics of the system. FMEA is used to determine the risk priority number of components and parts. The target reliability is satisfied by changing the design of components and parts with high-risk, hence the design for reliability to put the satellite in to the target orbit safely has been performed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3685-3691
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• 2015

We developed the platform safety step system for the passenger to avoid misstep accident and secure the pedestrian safety. In this study, we classify platform safety step system into hierarchy system and predict the failure rate of each part and calculate the failure rate & MTBF(Mean Time Between Failure) of each module(sub-system) by means of RBD(Reliability Block Diagram) & FTA(Fault Tree Analysis). Finally, we will propose the reliability analysis results for RAMS analysis of platform safety step system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.5
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• pp.1040-1048
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• 2016

Recently, the studies of integrated reliability analysis for combat systems are actively progressing. Especially, the research of integrated reliability analysis is emphasized to overcome limitations of the previous studies. In this paper, we propose a calculation technique for integrated hit probability based on front and side hit probabilities that analyzed in previous studies to improve the time-effectiveness. Also, we find out the integrated reliability of each component based on the integrated hit probability which is calculated, and we propose the method which applied the reliability block diagram technique to analyze the whole combat system of the reliability by function kills. For verifying the proposed method, we applied the proposed method to armored fighting vehicle model. The proposed method considers crew which does not considered the element in the previous study and expects to enhance the accuracy of reliability analysis and the time-effectiveness compared with the previous study.