Reliability Analysis, Safety Assessment and Optimization. Enrico Zio

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Series Editor’s Foreword

       Dr. Andre V. Kleyner

      The Wiley Series in Quality & Reliability Engineering aims to provide a solid educational foundation for researchers and practitioners in the field of quality and reliability engineering and to expand the knowledge base by including the latest developments in these disciplines.

      The importance of quality and reliability to a system can hardly be disputed. Product failures in the field inevitably lead to losses in the form of repair cost, warranty claims, customer dissatisfaction, product recalls, loss of sale, and in extreme cases, loss of life.

      Engineering systems are becoming increasingly complex with added functions and capabilities; however, the reliability requirements remain the same or even growing more stringent. Modeling and simulation methods, such as Monte Carlo simulation, uncertainty analysis, system optimization, Markov analysis and others, have always been important instruments in the toolbox of design, reliability and quality engineers. However, the growing complexity of the engineering systems, with the increasing integration of hardware and software, is making these tools indispensable in today’s product development process.

      The recent acceleration of the development of new technologies including digitalization, forces the reliability professionals to look for more efficient ways to deliver the products to market quicker while meeting or exceeding the customer expectations of high product reliability. It is important to comprehensively measure the ability of a product to survive in the field. Therefore, modeling and simulation is vital to the assessment of product reliability, including the effect of variance on the expected product life, even before the hardware is built. Variance is present in the design parameters, material properties, use conditions, system interconnects, manufacturing conditions, lot-to-lot variation and many other product inputs, making it difficult to assess. Thus, modeling and simulation may be the only tools to fully evaluate the effect of variance in the early product development phases and to eventually optimize the design.

The book you are about to read has been written by leading experts in the field of reliability modeling, analysis, simulation and optimization. The book covers important topics, such as system reliability assessment, modeling and simulation, multi-state systems, optimization methods and their applications, which are highly critical to meeting the high demands for quality and reliability. Achieving the optimal feasible performance of the system is eventually the final objective in modern product design and manufacturing, and this book rightfully puts a lot of emphasis on the process of optimization.

      Paradoxically, despite its evident importance, quality and reliability disciplines are somewhat lacking in today’s engineering educational curricula. Only few engineering schools offer degree programs, or even a sufficient set of courses, in quality and reliability methods. The topics of reliability analysis, accelerated testing, reliability modeling and simulation, warranty data analysis, reliability growth programs, reliability design optimization and other aspects of reliability engineering receive very little coverage in today’s engineering students curricula. As a result, the majority of the quality and reliability practitioners receive their professional training from colleagues, professional seminars and professional publications. In this respect, this book is intended to contribute to closing this gap and provide additional educational material as a learning opportunity for a wide range of readers from graduate level students to seasoned reliability professionals.

      We are confident that this book, as well as this entire book series, will continue Wiley’s tradition of excellence in technical publishing and provide a lasting and positive contribution to the teaching and practice of reliability and quality engineering.

Preface

      Engineering systems, like process and energy systems, transportation systems, structures like bridges, pipelines, etc., are designed to ensure successful operation throughout the anticipated service lifetime in compliance with given all-around sustainability requirements. This calls for design, operation, and maintenance solutions to achieve the sustainability targets with maximum benefit from system operation. Reliability, availability, maintainability and Safety criteria (RAMS) are among the indicators for measuring system functionality with respect to these intended targets.

      Today, modern engineering systems are becoming increasingly complex to meet the high expectations by the public for high functionality, performance, and reliability, and with this, RAMS properties have become further key issues in design, maintenance, and successful commercialization.

      With high levels of RAMS being demanded on increasingly complex systems, the reliability assessment and optimization methods and techniques need to be continuously improved and advanced. As a result, many efforts are being made to address various challenges in complex engineering system lifecycle management under the global trend of systems integration. Mathematically and computationally, the reliability assessment and optimization are challenged by various issues related to the uncertain, dynamic, multi-state, non-linear interdependent characteristics of the modern engineering systems and the problem of finding optimal solutions in irregular search spaces characterized by non-linearity, non-convexity, time-dependence and uncertainty.

      In the evolving and challenging RAMS engineering context depicted above, this book provides a precise technical view on system reliability methods and their application to engineering systems. The methods are described in detail with respect to their mathematical formulation and their application is illustrated through numerical examples and is discussed with respect to advantages and limitations. Applications to real world cases are given as a contribution to bridging the gap between theory and practice.

      The book can serve as a solid theoretical and practical basis for solving reliability assessment and optimization problems regarding systems of different engineering disciplines and for further developing and advancing the methods to address the newly arising challenges as technology evolves.

Reliability engineering is founded on scientific principles and deployed by mathematical tools for analyzing components and systems to guarantee they provide their functions as intended by design.

      On the other hand, technological advances continuously bring changes of perspectives, in response to the needs, interests, and priorities of the practical engineering world. As technology advances at a fast pace, the complexity of modern engineered systems increases and so do, at the same time, the requirements for performance, efficiency, and reliability. This brings new challenges that demand continuous developments and advancements in complex system reliability assessment and optimization.

      Therefore, system reliability assessment and optimization is inevitably a living field, with solution methodologies continuously evolving through the advancements of mathematics and simulation to follow up the development of new engineering technology and the changes in management perspectives. For this, advancements in the fields of operations research, reliability, and optimization