Reliability Analysis, Safety Assessment and Optimization. Enrico Zio
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СКАЧАТЬ consider the development and advancement in the fields of operations research, reliability, and optimization theory to tackle the reliability assessment and optimization of complex systems in different technological domains.

      The book is directed to graduate students, researchers and practitioners in the areas of system reliability, availability, maintainability and Safety (RAMS), and it is intended to provide an overview of the state of knowledge of and tools for reliability assessment and system optimization. It is organized in three parts to introduce fundamentals, and illustrate methods and applications.

      The first part reviews the concepts, definitions and metrics of reliability assessment and the formulations of different types of reliability optimization problems depending on the nature of the decision variables and considering redundancy allocation and maintenance and testing policies. Plenty of numerical examples are provided to accompany the understanding of the theoretical concepts and methods.

      The second part covers multi-state system (MSS) modeling and reliability evaluation, Markov processes, Monte Carlo simulation (MCS), and uncertainty treatment under poor knowledge. The reviewed methods range from piecewise-deterministic Markov processes (PDMPs) to belief functions.

      The third part of the book is devoted to system reliability optimization. In general terms, system reliability optimization involves defining the decision variables, the constraints and the single or multiple objective functions that describe the system reliability performance and involves searching for the combination of values of the decision variables that realize the target values the objective functions. Different formulations and methods are described with precise mathematical details and illustrative numerical examples, covering mathematical programming, evolutionary algorithms, multi-objective optimization (MOO) and optimization under uncertainty, including robust optimization (RO).

      Applications of the assessment and optimization methods to real-world cases are also given, concerning for example the reliability of renewable energy systems. From this point of view, the book bridges the gap between theoretical development and engineering practice.

      Live long and prosper, RAMS and system reliability! The authors would express the deepest appreciations to the great scholars along the line of honors and achievements for their inspirations and role modeling.

      Many thanks to the postgraduate students in Tsinghua: Tianli Men, Hanxiao Zhang, Ruochong Liu, Chen Zhang and Chuanzhou Jia. Thanks for their priceless efforts in editing, depicting, and proofreading in various chapters.

      The authors would like to specially thank the Wiley colleagues for their continuous and kindhearted monitoring and encouragement throughout the years.

      At last, this work is supported in part by the National Natural Science Foundation of China under a key project grant No. 71731008 and the Beijing Natural Science Foundation grant No. L191022.

      Notations: Part I

ttime point
nf(t)number of failed items
ns(t)number of the survived items
n0sample size
Trandom variable of the failure time
F(t)cdf of failure time
f(t)pdf of failure time
R(t)reliability at time t
h(t)hazard function at time t
H(t)cumulative hazard function at time t
Q^(t)estimate of the unreliability
R^(t)estimate of the reliability
D(t)component or system demand at time t
G(t)performance function at time t
MTTFmean time to failure
X
acrack length
Nload cycle
Qtotal volume of wear debris produced
Rs(t)reliability of the system at time t
(⋅)unreliability function of the system
Ccost
xdecision variable
g(x)inequality constraints
h(x)equality constraints
f(x)criterion function
D=(V, A)directed graph
d(⋅)

      Notations: Part II

ttime point
Sstate set
Mperfect state
x=(x1,…,xn)component state vector
X=(X1,…,Xn)state of all components
ϕ(⋅)structure function of the system
giperformance level of component i
λkjitransition rate of component i from state k to state j
Qkji(t)kernel of the SMP analogous to λkji of the CTMC
Tnitime of the n-th transition of component i
Gniperformance of component i at the n-th transition
θjki(t)probability that the process of component i starts from state j at time t
AφW(t)availability with a minimum on performance of total φ at time t
ui(z)universal generating function of component i
pij=Pr(Xi=j)probability of component i being at state j
p(t)state probability vector
λij(t)transition rate from state i to state j at time t in Markov process
Λtransition rate matrix
Π(⋅)possibility function
N(⋅)
Bel(⋅)belief СКАЧАТЬ