Dependability Engineering And Complex Systems

Typical contemporary complex system is a multifaceted amalgamation of technical, information, organization, software and human (users, administrators and management) resources. Complexity of such a system comes not only from its involved technical and organizational structure but mainly from complexity of information processes that must be implemented in the operational environment (data processing, monitoring, management, etc.). In such case traditional methods of reliability analysis focused mainly on technical level are usually insufficient in performance evaluation and more innovative methods of dependability analysis must be applied which are based on multidisciplinary approach to theory, technology and maintenance of systems operating in real (and very often unfriendly) environments. This monograph presents selected new developments in such areas of dependability research as system modelling, tools and methodologies for system analysis, data security, secure system design and specific dependability aspects in specialized technical applications. Many practical cases illustrate the universal rule that complexity and multiplicity of system processes, their concurrency and their reliance on embedded intelligence (human and artificial) significantly impedes construction of strict mathematical models and calls for application of intelligent and soft computing methods.

Complex System Reliability presents a state-of-the-art treatment of complex multi-channel system reliability assessment and provides the requisite tools, techniques and algorithms required for designing, evaluating and optimizing ultra-reliable redundant systems. Critical topics that make Complex System Reliability a unique and definitive resource include: • redundant system analysis for k-out-of-n systems (including complex systems with embedded k-out-of-n structures) involving both perfect and imperfect fault coverage; • imperfect fault coverage analysis techniques, including algorithms for assessing the reliability of redundant systems in which each element is subject to a given coverage value (element level coverage) or in which the system uses voting to avoid the effects of a failed element (fault level coverage); and • state-of-the-art binary decision diagram analysis techniques, including the latest and most efficient algorithms for the reliability assessment of large, complex redundant systems. This practical presentation includes numerous fully worked examples that provide detailed explanations of both the underlying design principles and the techniques (such as combinatorial, recursive and binary decision diagram algorithms) used to obtain quantitative results. Many of the worked examples are based on the design of modern digital fly-by-wire control system technology. Complex System Reliability provides in-depth coverage of systems subject to either perfect or imperfect fault coverage and also the most recent techniques for correctly assessing the reliability of redundant systems that use mid-value-select voting as their primary means of redundancy management. It is a valuable resource for those involved in the design and reliability assessment of highly reliable systems, particularly in the aerospace and automotive sectors.

Complex high-technology devices are in growing use in industry, service sectors, and everyday life. Their reliability and maintenance is of utmost importance in view of their cost and critical functions. This book focuses on this theme and is intended to serve as a graduate-level textbook and reference book for scientists and academics in the field. The chapters are grouped into five complementary parts that cover the most important aspects of reliability and maintenance: stochastic models of reliability and maintenance, decision models involving optimal replacement and repair, stochastic methods in software engineering, computational methods and simulation, and maintenance management systems. This wide range of topics provides the reader with a complete picture in a self-contained volume.

These proceedings present the results of the Eleventh International Conference on Dependability and Complex Systems DepCoS-RELCOMEX which took place in a picturesque Brunów Palace in Poland from 27th June to 1st July, 2016. DepCoS-RELCOMEX is a series of international conferences organized annually by Department of Computer Engineering of Wrocław University of Science and Technology since 2006. The roots of the series go as far back as to the seventies of the previous century – the first RELCOMEX conference took place in 1977 – and now its main aim is to promote a multi-disciplinary approach to dependability problems in theory and engineering practice of complex systems. Complex systems, nowadays most often computer-based and distributed, are built upon a variety of technical, information, software and human resources. The challenges in their design, analysis and maintenance not only originate from the involved technical and organizational structures but also from the complexity of the information processes that must be efficiently executed in a diverse, often hostile operational environment. Traditional methods of reliability evaluation focused only on technical resources are usually insufficient in this context and more innovative, multidisciplinary methods of dependability analysis must be applied. The diversity of the topics which need to be considered is well illustrated by the selection of the submissions in these proceedings with their subjects ranging from mathematical models and design methodologies through software engineering and data security issues up to practical problems in technical, e.g. transportation, systems.

This book gathers the proceedings of the 2017 DepCoS-RELCOMEX, an annual conference series that has been organized by the Department of Computer Engineering at the Faculty of Electronics, Wrocław University of Science and Technology, since 2006. Its mission is to continue the heritage of the other two cycles of events – the RELCOMEX conferences (1977–89) and Microcomputer Schools (1985–95) – so this year we can celebrate the 40th anniversary of its origins. In contrast to those preceding series, which were focused on conventional reliability analysis, the goal of DepCoS is to promote a more comprehensive approach to system performability, which is now commonly called dependability. This innovative research area provides answers to the latest challenges in reliability evaluation for contemporary complex systems. Its novelty is based on a multi-disciplinary approach to system theory, technology and maintenance of systems operating in real environments. Dependability analyses concentrate on the efficient completion of tasks, services and jobs by a system considered as a combination of technical, information and human assets, in contrast to “classical” reliability, which is generally limited to the analysis of technical resources and associated components and structures. The selection of papers for this volume illustrates the diversity of topics that need to be considered, from mathematical models and design methodologies through software engineering and data security issues, to practical engineering problems in technical systems. In addition, this edition of the conference hosted the 7th CrISS-DESSERT Workshop, which was devoted to the analysis and assurance of safety and cyber security in critical infrastructure and computer systems.

Simulation Methods for Reliability and Availability of Complex Systems discusses the use of computer simulation-based techniques and algorithms to determine reliability and availability (R and A) levels in complex systems. The book: shares theoretical or applied models and decision support systems that make use of simulation to estimate and to improve system R and A levels, forecasts emerging technologies and trends in the use of computer simulation for R and A and proposes hybrid approaches to the development of efficient methodologies designed to solve R and A-related problems in real-life systems. Dealing with practical issues, Simulation Methods for Reliability and Availability of Complex Systems is designed to support managers and system engineers in the improvement of R and A, as well as providing a thorough exploration of the techniques and algorithms available for researchers, and for advanced undergraduate and postgraduate students.

This book gathers the proceedings of the 2017 DepCoS-RELCOMEX, an annual conference series that has been organized by the Department of Computer Engineering at the Faculty of Electronics, Wrocław University of Science and Technology, since 2006. Its mission is to continue the heritage of the other two cycles of events? the RELCOMEX conferences (1977?89) and Microcomputer Schools (1985?95)? so this year we can celebrate the 40th anniversary of its origins. In contrast to those preceding series, which were focused on conventional reliability analysis, the goal of DepCoS is to promote a more comprehensive approach to system performability, which is now commonly called dependability. This innovative research area provides answers to the latest challenges in reliability evaluation for contemporary complex systems. Its novelty is based on a multi-disciplinary approach to system theory, technology and maintenance of systems operating in real environments. Dependability analyses concentrate on the efficient completion of tasks, services and jobs by a system considered as a combination of technical, information and human assets, in contrast to "classical" reliability, which is generally limited to the analysis of technical resources and associated components and structures. The selection of papers for this volume illustrates the diversity of topics that need to be considered, from mathematical models and design methodologies through software engineering and data security issues, to practical engineering problems in technical systems. In addition, this edition of the conference hosted the 7th CrISS-DESSERT Workshop, which was devoted to the analysis and assurance of safety and cyber security in critical infrastructure and computer systems.

The overwhelming majority of a software system’s lifespan is spent in use, not in design or implementation. So, why does conventional wisdom insist that software engineers focus primarily on the design and development of large-scale computing systems? In this collection of essays and articles, key members of Google’s Site Reliability Team explain how and why their commitment to the entire lifecycle has enabled the company to successfully build, deploy, monitor, and maintain some of the largest software systems in the world. You’ll learn the principles and practices that enable Google engineers to make systems more scalable, reliable, and efficient—lessons directly applicable to your organization. This book is divided into four sections: Introduction—Learn what site reliability engineering is and why it differs from conventional IT industry practices Principles—Examine the patterns, behaviors, and areas of concern that influence the work of a site reliability engineer (SRE) Practices—Understand the theory and practice of an SRE’s day-to-day work: building and operating large distributed computing systems Management—Explore Google's best practices for training, communication, and meetings that your organization can use