High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable de scriptions than can be obtained by means of low-level Petri nets-while, on the other hand, they still offer a wide range of analysis methods and tools. The step from low-level nets to high-level nets can be compared to the step from assembly languages to modem programming languages with an elaborated type concept. In low-level nets there is only one kind of token and this means that the state of a place is described by an integer (and in many cases even by a boolean value). In high-level nets each token can carry complex information which, e. g. , may describe the entire state of a process or a data base. Today most practical applications of Petri nets use one of the different kinds of high-level nets. A considerable body of knowledge exists about high-level Petri nets this includes theoretical foundations, analysis methods and many applications. Unfortunately, the papers on high-level Petri nets have been scattered throughout various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets.

This book presents the definition, validation and application of a selected set of Petri nets. It first introduces the basic models including time and stochastic extensions, in particular place-transition and high level Petri nets. Their modeling and design capabilities are illustrated by a set of representations of interest in operating and communication systems. The volume then addresses the related verification problems and proposes corresponding solutions by introducing the main notions needed to fully understand the behavior and properties behind Petri nets. Particular attention is devoted to how systems can be fully represented and analyzed in terms of their behavioral, time and stochastic aspects by using the same formal approach and semantical basis. Finally, illustrative examples are presented in the important fields of interoperability in telecommunication services, programmation languages, multimedia architectures, manufacturing systems and communication protocols.

Driven by the request for increased productivity, flexibility, and competitiveness, modern civilization increasingly has created high-performance discrete event dynamic systems (DEDSs). These systems exhibit concurrent, sequential, competitive activities among their components. They are often complex and large in scale, and necessarily flexible and thus highly capital-intensive. Examples of systems are manufacturing systems, communication networks, traffic and logistic systems, and military command and control systems. Modeling and performance evaluation play a vital role in the design and operation of such high-performance DEDSs and thus have received widespread attention from researchers over the past two decades. One methodology resulting from this effort is based on timed Petri nets and related graphical and mathematical tools. The popularity that Petri nets have been gaining in modeling of DEDSs is due to their powerful representational ability of concurrency and synchronization; however these properties of DEDSs cannot be expressed easily in traditional formalisms developed for analysis of `classical' systems with sequential behaviors. This book introduces the theories and applications of timed Petri nets systematically. Moreover, it also presents many practical applications in addition to theoretical developments, together with the latest research results and industrial applications of timed Petri nets. Timed Petri Nets: Theory and Application is intended for use by researchers and practitioners in the area of Discrete Event Dynamic Systems.

High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable de scriptions than can be obtained by means of low-level Petri nets-while, on the other hand, they still offer a wide range of analysis methods and tools. The step from low-level nets to high-level nets can be compared to the step from assembly languages to modem programming languages with an elaborated type concept. In low-level nets there is only one kind of token and this means that the state of a place is described by an integer (and in many cases even by a boolean value). In high-level nets each token can carry complex information which, e. g. , may describe the entire state of a process or a data base. Today most practical applications of Petri nets use one of the different kinds of high-level nets. A considerable body of knowledge exists about high-level Petri nets this includes theoretical foundations, analysis methods and many applications. Unfortunately, the papers on high-level Petri nets have been scattered throughout various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets.

Hardware Design and Petri Nets presents a summary of the state of the art in the applications of Petri nets to designing digital systems and circuits. The area of hardware design has traditionally been a fertile field for research in concurrency and Petri nets. Many new ideas about modelling and analysis of concurrent systems, and Petri nets in particular, originated in theory of asynchronous digital circuits. Similarly, the theory and practice of digital circuit design have always recognized Petri nets as a powerful and easy-to-understand modelling tool. The ever-growing demand in the electronic industry for design automation to build various types of computer-based systems creates many opportunities for Petri nets to establish their role of a formal backbone in future tools for constructing systems that are increasingly becoming distributed, concurrent and asynchronous. Petri nets have already proved very effective in supporting algorithms for solving key problems in synthesis of hardware control circuits. However, since the front end to any realistic design flow in the future is likely to rely on more pragmatic Hardware Description Languages (HDLs), such as VHDL and Verilog, it is crucial that Petri nets are well interfaced to such languages. Hardware Design and Petri Nets is divided into five parts, which cover aspects of behavioral modelling, analysis and verification, synthesis from Petri nets and STGs, design environments based on high-level Petri nets and HDLs, and finally performance analysis using Petri nets. Hardware Design and Petri Nets serves as an excellent reference source and may be used as a text for advanced courses on the subject.

With their intuitive graphical approach and expressive analysis techniques, Petri nets are suitable for a wide range of applications and teaching scenarios, and they have gained wide acceptance as a modeling technique in areas such as software design and control engineering. The core theoretical principles have been studied for many decades and there is now a comprehensive research literature that complements the extensive implementation experience. In this book the author presents a clear, thorough introduction to the essentials of Petri nets. He explains the core modeling techniques and analysis methods and he illustrates their usefulness with examples and case studies. Part I describes how to use Petri nets for modeling; all concepts are explained with the help of examples, starting with a generic, powerful model which is also intuitive and realistic. Part II covers the essential analysis methods that are specific to Petri nets, introducing techniques used to formulate key properties of system nets and algorithms for proving their validity. Part III presents case studies, each introducing new concepts, properties and analysis techniques required for very different modeling tasks. The author offers different paths among the chapters and sections: the elementary strand for readers who wish to study only elementary nets; the modeling strand for those who wish to study the modeling but not the analysis of systems; and finally the elementary models of the modeling strand for those interested in technically simple, but challenging examples and case studies. The author achieves an excellent balance between consistency, comprehensibility and correctness in a book of distinctive design. Among its characteristics, formal arguments are reduced to a minimum in the main text with many of the theoretical formalisms moved to an appendix, the explanations are supported throughout with fully integrated graphical illustrations, and each chapter ends with exercises and recommendations for further reading. The book is suitable for students of computer science and related subjects such as engineering, and for a broad range of researchers and practitioners.

Supervisory Control of Discrete Event Systems Using Petri Nets presents a novel approach to its subject. The concepts of supervisory control and discrete event systems are explained, and the background material on general Petri net theory necessary for using the book's control techniques is provided. A large number of examples is used to illustrate the concepts and techniques presented in the text, and there are plenty of references for those interested in additional study or more information on a particular topic. Supervisory Control of Discrete Event Systems Using Petri Nets is intended for graduate students, advanced undergraduates, and practicing engineers who are interested in the control problems of manufacturing, communication and computer networks, chemical process plants, and other high-level control applications. The text is written from an engineering perspective, but it is also appropriate for students of computer science, applied mathematics, or economics. The book contains enough background material to stand alone as an introduction to supervisory control with Petri nets, but it may also be used as a supplemental text in a course on discrete event systems or intelligent autonomous control.