Component Reliability Importance Measure in Presence of Transient Faults

Importance measures are widely used to characterize the contribution of components to the system performance such as reliability, availability, risk, etc, and thus give great help in identifying system weaknesses and prioritizing system improvement activities. Although much work has been carried out on component importance analysis, most studies only concern the consistent states of components within which components exhibit consistent performance until state changes happen. Unfortunately, field data shows that many transient faults in components may result in severe consequences without causing any state changes, and, this can lead to a misunderstanding of component importance. This paper focuses on the reliability importance analysis in presence of transient faults, and proposes a composite measure for evaluation. A sample series parallel system is analyzed to illustrate the use of this measure.

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Dynamic Importance Analysis of Components of Complex Mechanical System by Small Sample Data

Volume 3: Manufacturing Equipment and Systems ◽

10.1115/msec2018-6316 ◽

2018 ◽

Author(s):

Li Yangfan ◽

Zhang Yingjie ◽

Dai Bochao ◽

Zhang Lin

Keyword(s):

Mechanical System ◽

System Performance ◽

Small Sample ◽

System Component ◽

Importance Measure ◽

Complex Mechanical System ◽

Failure Data ◽

Component Importance ◽

Sample Data ◽

Importance Analysis

Importance analysis deals with the influence of individual system component on system operation. Thus, a lot of failure data should be collected to make the analysis more accurate. This paper mainly focuses on the numerical estimation of component importance in complex mechanical system which is considered as a multi-state system with few failure data. In order to evaluate components’ failure probability distribution by small sample data, a time integral importance measure (TIIM) approach is proposed. In this measure, we aim to measure component importance using the change of system performance caused by wiping off component failure data. On this basis, the dynamic importance fluctuation of a component can be measured by calculating criticality of each state of the component. The approach has been verified by probability analysis of CNC machine tools. The main contribution of this work is the proposed dynamic importance measure which can be used to identify the key state of a component that influences system performance most by small-sample data.

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Components Importance Analysis Fault Tree of Power Transformer of Gi Simangkuk Switchyard in Indonesia

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.694-697.907 ◽

2013 ◽

Vol 694-697 ◽

pp. 907-910 ◽

Cited By ~ 1

Author(s):

Josep Franklin Sihite ◽

Takehisa Kohda

Keyword(s):

System Reliability ◽

Power Transformer ◽

Fault Tree ◽

Importance Measure ◽

Component Importance ◽

Safety Improvement ◽

System Components ◽

Importance Analysis

The purpose of this paper is to study the importance measures of power transformer system components. Importance measures analysis is a key part of the system reliability quantification process which are most effective towards safety improvement. This paper presented an application and results of the importance measures analysis of a power transformer system of GI Simangkuk switchyard in Indonesia by using Birnbaum importace measures, critically importance measure, and Fussel-Vessely importance measures. These method present the rank of the component importance measures quantitavily according to their contribution to system reliability and safety.

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Reliability Analysis and Imprecise Component Importance Measure of Redundant Systems of OWTs Based on Component Swapping

Applied Sciences ◽

10.3390/app10041432 ◽

2020 ◽

Vol 10 (4) ◽

pp. 1432

Author(s):

Yao Li ◽

Caichao Zhu ◽

Zi Wang

Keyword(s):

Reliability Analysis ◽

Wind Turbines ◽

Offshore Wind ◽

Importance Measure ◽

Offshore Wind Turbine ◽

Component Reliability ◽

Joint Reliability ◽

Component Importance ◽

Attractive Option ◽

Redundant Systems

Due to the high cost of failures of wind turbines, redundancy designs are commonly applied in wind turbines for improving the reliability and availability of systems. For this reason, replacing failed components with other working components of the same type in redundant systems is becoming an attractive option of maintenance strategies towards more resilient systems. To quantitatively evaluate system’s reliability, this paper focuses on the reliability analysis of redundant systems of offshore wind turbines based on swapping existing components. The survival signature-based component swapping method is introduced to describe the new structure-function of the system upon swapping. Furthermore, the reliability model of redundant systems is established using the fault tree and survival signature. Following this, the influences of component swapping on component reliability importance measure (marginal reliability importance and joint reliability importance) without and with considerations of the imprecision of failure rates are explored. Finally, a 5MW offshore wind turbine is presented to show the applicability of the proposed approach for redundant systems, and the results show that the proposed approach can obtain realistic reliability assessment of redundant systems and considering component swapping can significantly improve system reliability.

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Importance Measures for NFV Data Center: An Availability Evaluation

10.5753/wpietf.2018.3213 ◽

2018 ◽

Cited By ~ 2

Author(s):

Rafael Souza ◽

Marcelo Santos ◽

Stênio Fernandes

Keyword(s):

Data Center ◽

Data Centers ◽

Network Function Virtualization ◽

Importance Measure ◽

Substantial Impact ◽

Network Function ◽

Component Importance ◽

Importance Analysis ◽

Reliability Block Diagrams ◽

The Impact

Data center infrastructures need to provide high availability of their services. Unexpected spikes of downtime in data centers lead to financial losses. Besides, there are intangible costs such as damaged reputation, low employee satisfaction, and reduced customer retention. In this context, Network Function Virtualization (NFV) emerged as a paradigm that assists data centers in becoming more dynamic and flexible. This paper presents an availability evaluation and importance analysis under the redundancy of NFV in data centers. The NFV data center component importance is represented by using Reliability Block Diagrams (RBD). The proposed models have identified the availability importance and critical devices in an NFV data center. This research also suggests alternatives for device redundancy to reach higher availability and proposes a new importance measure for analyzing the impact of NFV factors on data center availability. The measure can evaluate the degree of the impact of a failure on the data center, therefore, help to identify the factors with a substantial impact on data center availability.

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Reliability Optimization and Importance Analysis of Circular-Consecutive k-out-of-n System

Mathematical Problems in Engineering ◽

10.1155/2017/1831537 ◽

2017 ◽

Vol 2017 ◽

pp. 1-17

Author(s):

Shuai Zhang ◽

Jiang-bin Zhao ◽

Hong-guang Li ◽

Ning Wang

Keyword(s):

Genetic Algorithm ◽

Numerical Experiments ◽

Search Algorithms ◽

Typical Case ◽

Reliability Optimization ◽

Component Reliability ◽

Component Importance ◽

Optimal Permutation ◽

Importance Analysis ◽

Effectiveness And Efficiency

The circular-consecutive k-out-of-n:F(G) system (Cir/Con/k/n:F(G) system) usually consists of n components arranged in a circle where the system fails (works) if consecutive k components fail (work). The optimization of the Cir/Con/k/n system is a typical case in the component assignment problem. In this paper, the Birnbaum importance-based genetic algorithm (BIGA), which takes the advantages of genetic algorithm and Birnbaum importance, is introduced to deal with the reliability optimization for Cir/Con/k/n system. The detailed process and property of BIGA are put forward at first. Then, some numerical experiments are implemented, whose results are compared with two classic Birnbaum importance-based search algorithms, to evaluate the effectiveness and efficiency of BIGA in Cir/Con/k/n system. Finally, three typical cases of Cir/Con/k/n systems are introduced to demonstrate the relationships among the component reliability, optimal permutation, and component importance.

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COMBINATORIAL APPROACH TO COMPUTING COMPONENT IMPORTANCE INDEXES IN COHERENT SYSTEMS

Probability in the Engineering and Informational Sciences ◽

10.1017/s026996481100026x ◽

2011 ◽

Vol 26 (1) ◽

pp. 117-128 ◽

Cited By ~ 17

Author(s):

Ilya B. Gertsbakh ◽

Yoseph Shpungin

Keyword(s):

System Reliability ◽

Simple Formula ◽

Analytic Formula ◽

Importance Measure ◽

Coherent Systems ◽

Joint Reliability ◽

Component Importance ◽

Definition Of ◽

Combinatorial Parameter ◽

Combinatorial Representation

We consider binary coherent systems with independent binary components having equal failure probability q. The system DOWN probability is expressed via its signature's combinatorial analogue, the so-called D-spectrum. Using the definition of the Birnbaum importance measure (BIM), we introduce for each component a new combinatorial parameter, so-called BIM-spectrum, and develop a simple formula expressing component BIM via the component BIM-spectrum. Further extension of this approach allows obtaining a combinatorial representation for the joint reliability importance (JRI) of two components. To estimate component BIMs and JRIs, there is no need to know the analytic formula for system reliability. We demonstrate how our method works using the Monte Carlo approach. We present several examples of estimating component importance measures in a network when the DOWN state is defined as the loss of terminal connectivity.

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Component importance in coherent systems with exchangeable components

Journal of Applied Probability ◽

10.1239/jap/1445543851 ◽

2015 ◽

Vol 52 (3) ◽

pp. 851-863 ◽

Cited By ~ 3

Author(s):

Serkan Eryilmaz

Keyword(s):

Importance Measure ◽

Coherent System ◽

Coherent Systems ◽

System A ◽

Component Importance

This paper is concerned with the Birnbaum importance measure of a component in a binary coherent system. A representation for the Birnbaum importance of a component is obtained when the system consists of exchangeable dependent components. The results are closely related to the concept of the signature of a coherent system. Some examples are presented to illustrate the results.

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