Preface xiii
Acronyms and Notations xv
1 What Is Reliability? 1
1.1 Reliability as a Property of Technical Objects, 1
1.2 Other âIlitiesâ, 2
1.3 Hierarchical Levels of Analyzed Objects, 5
1.4 How Can Reliability Be Measured?, 5
1.5 Software Reliability, 7
1.5.1 Case Study: Avalanche of Software Failures, 8
2 Unrecoverable Objects 9
2.1 Unit, 9
2.1.1 Probability of Failure-Free Operation, 9
2.1.2 Mean Time to Failure, 10
2.2 Series Systems, 11
2.2.1 Probability of Failure-Free Operation, 11
2.2.2 Mean Time to Failure, 13
2.3 Parallel System, 14
2.3.1 Probability of Failure-Free Operation, 14
2.3.2 Mean Time to Failure, 18
2.4 Structure of Type âk-out-of-nâ, 20
2.5 Realistic Models of Loaded Redundancy, 22
2.5.1 Unreliable Switching Process, 23
2.5.2 Non-Instant Switching, 23
2.5.3 Unreliable Switch, 24
2.5.4 Switch Serving as Interface, 25
2.5.5 Incomplete Monitoring of the Operating Unit, 26
2.5.6 Periodical Monitoring of the Operating Unit, 28
2.6 Reducible Structures, 28
2.6.1 Parallel-Series and Series-Parallel Structures, 28
2.6.2 General Case of Reducible Structures, 29
2.7 Standby Redundancy, 30
2.7.1 Simple Redundant Group, 30
2.7.2 Standby Redundancy of Type âk-out-of-nâ, 33
2.8 Realistic Models of Unloaded Redundancy, 34
2.8.1 Unreliable Switching Process, 34
2.8.2 Non-Instant Switching, 35
2.8.3 Unreliable Switch, 35
2.8.4 Switch Serving as Interface, 37
2.8.5 Incomplete Monitoring of the Operating Unit, 38
3 Recoverable Systems: Markov Models 40
3.1 Unit, 40
3.1.1 Markov Model, 41
3.2 Series System, 47
3.2.1 Turning Off System During Recovery, 47
3.2.2 System in Operating State During Recovery: Unrestricted Repair, 49
3.2.3 System in Operating State During Recovery: Restricted Repair, 51
3.3 Dubbed System, 53
3.3.1 General Description, 53
3.3.2 Nonstationary Availability Coefficient, 54
3.3.3 Stationary Availability Coefficient, 58
3.3.4 Probability of Failure-Free Operation, 59
3.3.5 Stationary Coefficient of Interval Availability, 62
3.3.6 Mean Time to Failure, 63
3.3.7 Mean Time Between Failures, 63
3.3.8 Mean Recovery Time, 65
3.4 Parallel Systems, 65
3.5 Structures of Type âm-out-of-nâ, 66
4 Recoverable Systems: Heuristic Models 72
4.1 Preliminary Notes, 72
4.2 Poisson Process, 75
4.3 Procedures over Poisson Processes, 78
4.3.1 Thinning Procedure, 78
4.3.2 Superposition Procedure, 80
4.4 Asymptotic Thinning Procedure over Stochastic Point Process, 80
4.5 Asymptotic Superposition of Stochastic Point Processes, 82
4.6 Intersection of Flows of Narrow Impulses, 84
4.7 Heuristic Method for Reliability Analysis of Series Recoverable Systems, 87
4.8 Heuristic Method for Reliability Analysis of Parallel Recoverable Systems, 87
4.8.1 Influence of Unreliable Switching Procedure, 88
4.8.2 Influence of Switchâs Unreliability, 89
4.8.3 Periodical Monitoring of the Operating Unit, 90
4.8.4 Partial Monitoring of the Operating Unit, 91
4.9 Brief Historical Overview and Related Sources, 93
5 Time Redundancy 95
5.1 System with Possibility of Restarting Operation, 95
5.2 Systems with âAdmissibly Short Failuresâ, 98
5.3 Systems with Time Accumulation, 99
5.4 Case Study: Gas Pipeline with an Underground Storage, 100
5.5 Brief Historical Overview and Related Sources, 102
6 âAgingâ Units and Systems of âAgingâ Units 103
6.1 Chebyshev Bound, 103
6.2 âAgingâ Unit, 104
6.3 Bounds for Probability of Failure-Free Operations, 105
6.4 Series System Consisting of âAgingâ Units, 108
6.4.1 Preliminary Lemma, 108
6.5 Series System, 110
6.5.1 Probability of Failure-Free Operation, 110
6.5.2 Mean Time to Failure of a Series System, 112
6.6 Parallel System, 114
6.6.1 Probability of Failure-Free Operation, 114
6.6.2 Mean Time to Failure, 117
6.7 Bounds for the Coefficient of Operational Availability, 119
6.8 Brief Historical Overview and Related Sources, 121
7 Two-Pole Networks 123
7.1 General Comments, 123
7.1.1 Method of Direct Enumeration, 125
7.2 Method of Boolean Function Decomposition, 127
7.3 Method of Paths and Cuts, 130
7.3.1 Esaryâ"Proschan Bounds, 130
7.3.2 âImprovementsâ of Esaryâ"Proschan Bounds, 133
7.3.3 Litvakâ"Ushakov Bounds, 135
7.3.4 Comparison of the Two Methods, 139
7.4 Brief Historical Overview and Related Sources, 140
8 Performance Effectiveness 143
8.1 Effectiveness Concepts, 143
8.2 General Idea of Effectiveness Evaluation, 145
8.2.1 Conditional Case Study: Airport Traffic Control System, 147
8.3 Additive Type of System Unitsâ Outcomes, 150
8.4 Case Study: ICBM Control System, 151
8.5 Systems with Intersecting Zones of Action, 153
8.6 Practical Recommendation, 158
8.7 Brief Historical Overview and Related Sources, 160
9 System Survivability 162
9.1 Illustrative Example, 166
9.2 Brief Historical Overview and Related Sources, 167
10 Multistate Systems 169
10.1 Preliminary Notes, 169
10.2 Generating Function, 169
10.3 Universal Generating Function, 172
10.4 Multistate Series System, 174
10.4.1 Series Connection of Piping Runs, 174
10.4.2 Series Connection of Resistors, 177
10.4.3 Series Connections of Capacitors, 179
10.5 Multistate Parallel System, 181
10.5.1 Parallel Connection of Piping Runs, 181
10.5.2 Parallel Connection of Resistors, 182
10.5.3 Parallel Connections of Capacitors, 182
10.6 Reducible Systems, 183
10.7 Conclusion, 190
10.8 Brief Historical Overview and Related Sources, 190
Appendix A Main Distributions Related to Reliability Theory 195
A.1 Discrete Distributions, 195
A.1.1 Degenerate Distribution, 195
A.1.2 Bernoulli Distribution, 196
A.1.3 Binomial Distribution, 197
A.1.4 Poisson Distribution, 198
A.1.5 Geometric Distribution, 200
A.2 Continuous Distributions, 201
A.2.1 Intensity Function, 201
A.2.2 Continuous Uniform Distribution, 202
A.2.3 Exponential Distribution, 203
A.2.4 Erlang Distribution, 204
A.2.5 Hyperexponential Distribution, 205
A.2.6 Normal Distribution, 207
A.2.7Weibullâ"Gnedenko Distribution, 207
Appendix B Laplace Transformation 209
Appendix C Markov Processes 214
C.1 General Markov Process, 214
C.1.1 Nonstationary Availability Coefficient, 216
C.1.2 Probability of Failure-Free Operation, 218
C.1.3 Stationary Availability Coefficient, 220
C.1.4 Mean Time to Failure and Mean Time Between Failures, 221
C.1.5 Mean Recovery Time, 222
C.2 Birthâ"Death Process, 223
Appendix D General Bibliography 227
Index 231
