An Improvement Strategy Based on the Failure Risk and Corrective Action Prioritization in Service FMEA
- Abstract
- As the contribution of service sectors to global economy grows, the importance of delivering error free service operation is undeniable. This thesis is concerned with endeavor to improve some limitations of the conventional FMEA in risk estimation and improvement strategy selection in service FMEA. In attempt to searching for new FMEA research opportunities in service sector, initial literature survey is performed. The results of the survey indicated the determination of failure occurrence rate is still based on subjective judgment, ignoring failure time occurrence and impact of business environment in proposing failure rectification effort. In this thesis, several ideas are suggested for improving the previous FMEA methodologies as below:
i) The expected loss model. Although many methodologies have been proposed to overcome limitations of the RPN estimation in conventional FMEA, the determination of the probability component in RPN estimation is still based on 1-10 ordinal scale with no scientific basis. Instead of using the RPN (Risk Priority Number) as metric to rank criticality of service failure in conventional FMEA, an expected loss model based on the conditional probability theory is proposed. By using the expected loss model, determination of failure probability component can be accomplished into more scientifically basis and can lead to an improved failure alleviation effort.
ii) Time-dependent expected loss model. Attribution of failure time occurrence is important in quality loss quantification; however, such aspect is not covered by conventional FMEA. Considering this discrepancy, a time-dependent expected loss model which based on assumption of constant failure occurrence rate is formulated. The result of numerical estimation based on time-dependent expected loss model indicated that failure time occurrence cannot be neglected in quantifying quality loss during time span of service system’s mission. Inclusion of failure time occurrence will provide decision makers with more realistic quality loss quantification.
iii) SWOT based corrective action strategy selection model. In spite of having equal important in risk management platform, reprioritization of FMEA-based competing corrective actions selection is still based on internal failure evaluation. The reality that business system is interacting with both of its inner and outer of environments is not considered. Considering impact of business environment, SWOT Analysis is integrated in estimating preference score of decision makers in appraising competing corrective actions. A model to estimate the benefit of considering impact of business environments based on impact factor of SWOT variables and their correlations with competing corrective actions are proposed.
All models presented in this thesis are intended to contribute to the body of knowledge. By using the models, if compared to conventional FMEA, the probability components of the RPN can be determined more scientifically. In addition, inclusion of failure time and utilization of the three models of loss function, the possibility of business loss escalation during system operational mission can be accommodated. Considering impact factor of SWOT variables in risk-based strategy selection enables decision makers to estimate consider impact of business environments prior determining strategic business decisions.
- Issued Date
- 2012
- Awarded Date
- 2012. 8
- Type
- Dissertation
- Publisher
- Pukyong National University
- Affiliation
- 부경대학교 산업대학원
- Department
- 산업대학원 시스템경영공학과
- Advisor
- Hyuck Moo Kwon
- Table Of Contents
- Table of Contents
Page
Chapter 1 Introduction 1
1.1 Review and Classification of Previous Works on Risk Evaluation 1
and Strategy Selection In FMEA Literature
1.2 Some Comments on Failure Risk Evaluation and Strategy Selection in FMEA 3
1.3 Observable Gaps and Research Directions 5
1.4 Research Contributions 10
1.5 Research Limitations and Thesis Structure 11
Chapter 2 Research Problem Formulations and Basic Concepts Employed in Undertaking the Research 15
2.1 Research problem Formulation 16
2.2 Research Strategy 16
2.3 Basic Methodologies Employed 17
2.3.1 FMEA 17
2.3. 2 Corrective and Preventive Action 24
2.3.3 Root Cause Analysis 27
2.4 SWOT Analysis 29
2.5 Analytical Hierarchy Process 31
Chapter 3 An Expected Loss Model for Risk Priority in Service FMEA 35
3.1 Introduction 35
3.2 The Expected Loss Model 37
3.2. 1 The Law of Total Probability 37
3.2. 2 Bayes Theorem for Discrete Outcomes 38
3.3 Risk Prioritization by expected loss model 38
3.4 Procedure to Perform Expected Loss Model in Service FMEA 46
3.5 Estimation of the Components of Expected Loss Model 48
3.5.1 The Probability Components 48
3.5.2 The Loss Components 49
3.6 An Example 52
3.7 Discussions 58
3.7.1 Advantages of the Expected Loss Model 60
3.7.2 Limitations of the Expected Loss Model 60
Chapter 4. A Time Dependent Expected Loss Model in FMEA 64
4.1 Introduction 64
4.2 Quantifying Risk Components in FMEA 66
4.2.1 Failure Severity Component in Time Dependent FMEA 67
4.2.2 Failure Occurrence Components in Time Dependent FMEA 68
4.2.3 Failure Detect ability Components in Time Dependent FMEA 69
4.3 The Time Dependent Expected Loss Model 70
4.4 Procedure to Perform Time Dependent Expected Loss Model 73
4.5 Numerical Example 74
4.6 Discussions 75
4.6.1 Advantages of Using Time Dependent Expected Loss Model 79
4.6.2 Limitations of the Time Dependent Expected Loss Model 80
Chapter 5 Selecting Corrective Action Strategy based on SWOT Analysis in Service FMEA 82
5.1 Introduction 83
5.2 Integration of SWOT Analysis in FMEA 86
5.2.1 Impact Factor of SWOT Variables 89
5.2.2 Estimating Correction between CA and SWOT Variables 91
5.3 Estimating Preference Score as Basis for Selecting Corrective Actions 92
5.4 Evaluating Performance of Implemented Corrective Actions 93
5.5 Estimating Time, Quality, and Cost of Implementing Corrective Action 96
5.6 Application Procedure 96
5.7 Illustrative Example 97
5.8 Solution Procedures 97
5.9 Discussions 105
5.9.1 Advantages of the Proposed Models 106
5.9.2 Limitations of the Proposed Models 106
Chapter 6 Conclusions and Extensions 109
6.1 Conclusions 109
6.2 Extensions for Further Investigation 111
References 114
Appendix 1 129
Appendix 2 130
Abstract 131
Acknowledgement 133
- Degree
- Doctor
- Files in This Item:
-
-
Download
An Improvement Strategy Based on the Failure Risk and Corrective Action Prioritization in Service FM.pdf
기타 데이터 / 2.11 MB / Adobe PDF
-
Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.