Showing papers on "Petri net published in 1984"
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TL;DR: It is shown that GSPN are equivalent to continuous-time stochastic processes, and solution methods for the derivation of the steady state probability distribution are presented.
Abstract: Generalized stochastic Petri nets (GSPNs) are presented and are applied to the performance evaluation of multiprocessor systems. GSPNs are derived from standard Petri nets by partitioning the set of transitions into two subsets comprising timed and immediate transitions. An exponentially distributed random firing time is associated with each timed transition, whereas immediate transitions fire in zero time. It is shown that GSPN are equivalent to continuous-time stochastic processes, and solution methods for the derivation of the steady state probability distribution are presented. Examples of application of gspn models to the performance evaluation of multiprocessor systems show the usefulness and the effectiveness of this modeling tool. 15 references.
1,394 citations
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TL;DR: An algorithm is presented for the general Petri net reachability problem, based on a generalization of the basic reachability tree construction which is made symmetric with respect to the initial and final marking.
Abstract: An algorithm is presented for the general Petri net reachability problem. It is based on a generalization of the basic reachability tree construction which is made symmetric with respect to the ini...
675 citations
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01 Jan 1984
TL;DR: An Extended Stochastic Petri Net (ESPN) model, useful for modeling systems which exhibit concurrent, asynchronous, or nondeterministic behavior is developed and applications demonstrating the flexibility of the model for a variety of system modeling applications are presented.
Abstract: An Extended Stochastic Petri Net (ESPN) model, useful for modeling systems which exhibit concurrent, asynchronous, or nondeterministic behavior is developed. Applications demonstrating the flexibility of the model for a variety of system modeling applications are presented. Analytic techniques for the representation of a class of ESPNs as Markov or semi-Markov processes are discussed, as in the simulation of more general models. Finally, DEEP (The Duke ESPN Evaluation Package) is previewed.
260 citations
01 Jan 1984
TL;DR: A version of timed Petri Nets which accurately models communication protocols, and which can be analyzed using Timed Reachability Graphs is proposed and shown to be applicable to a larger class of Timed Petri Net than previously thought.
Abstract: Author(s): Razouk, Rami R.; Phelps, Charles V. | Abstract: Petri Nets have been successfully used to model and evaluate the performance of distributed systems. Several researchers have extended the basic Petri Net model to include time, and have demonstrated that restricted classes of Petri Nets can be analyzed efficiently. Unfortunately, the restrictions prohibit the techniques from being applied to many interesting systems, e.g. communication protocols. This paper proposes a version of timed Petri Nets which accurately models communication protocols, and which can be analyzed using Timed Reachability Graphs. Procedures for constructing and analyzing these graphs are presented. The analysis is shown to be applicable to a larger class of Timed Petri Nets than previously thought. The model and the analysis technique are demonstrated using a simple communication protocol.
107 citations
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TL;DR: Il existe deux approches du temps de modelisation des operations, la premiere methode associe le temps aux transitions tandis que la seconde associes le Temps au lieu.
106 citations
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16 Jul 1984TL;DR: It is proved, that the interleaved behaviour of the resulting nets is equivalent to Milner's semantics and it is shown that a large class of CCS programs can be represented by finite nets and that this is impossible for the whole CCS.
Abstract: We give a partial order semantics to (pure) CCS via a translation into Petri nets and prove, that the interleaved behaviour of the resulting nets is equivalent to Milner's semantics. We show that a large class of CCS programs can be represented by finite nets and that this is impossible for the whole CCS.
83 citations
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11 Apr 1984TL;DR: This work addresses another problem, that of constructions on Petri nets and how to prove properties of a compound process by proving properties of its components.
Abstract: Petri nets are a fundamental model of concurrent processes and have a wide range of applications. They can be viewed as generalisation of transition systems in which concurrency is not simulated by non-deterministic interleaving. They were invented by C. A. Petri in the 60's. (A reference work is [Br].) It can be argued that the main effort and success of Petri Net Theory has been in developing techniques for showing properties of arbitrary Petri nets, e.g. Kurt Lautenbach has used techniques of linear algebra to discover invariants (properties which hold at all reachable markings). These techniques can be used to prove properties of concurrent programs. First represent the program as one big net and then prove properties about that. The problem is that big nets get out of hand, and more easily out of mind. For this reason chiefly, Hartmann Genrich, Kurt Lauteubach and Kurt Jensen invented predicate transition nets and coloured nets [GL, J] and accompanying techniques to find their invariants. Although they certainly do give a more compact way to model programs and systems they are necessarily more complicated, are more like programs, and need a semantics to relate them to structures which are more simple and universal. We address another problem, that of constructions on Petri nets and how to prove properties of a compound process by proving properties of its components. The constructions follow from a new notion of morphism on Petri nets—it is not the same as Petri's original notion. The morphisms respect the token game unlike Petri's original. The category of nets with the new morphisms has a product which is closely related to various parallel compositions which have been defined on labelled Petri nets for synchronising processes (see e.g. the compositions on nets defined in [LS,...] and section 3). It has a coproduct which is a generalised form of the "sum" operation as used for example in [M]. One can use Petri nets to give semantics to programming languages. But, what is the semantics of nets? In themselves nets are complicated objects whose behaviour is rather intricate. When do Petri nets have the same behaviour? Attempting to answer these questions leads naturally to occurrence nets first introduced in [NPW1, 2]. Occurrence nets form' a subcategory which bears a pleasant relation to the larger category of nets; the inclusion functor has a right adjoint which is an operation taking a net to its unfolding …
78 citations
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TL;DR: A subclass of Petri nets called live and safe free choice nets (LSFC nets) is studied and it is shown that the restricted combination of concurrency and choice as represented by LSFC nets leads to a number of attractive system properties.
Abstract: A subclass of Petri nets called live and safe free choice nets (LSFC nets) is studied. LSFC nets model distributed systems that can exhibit both nonsequential and nondeterministic behaviours. It is shown that the restricted combination of concurrency and choice as represented by LSFC nets leads to a number of attractive system properties. It is also shown, through examples, that a “less” restrictive combination of concurrency and choice destroys these properties.
72 citations
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TL;DR: The aim is to better understand the relationships between choice and concurrency that lead to the good behaviour of distributed systems and to formulate a model based on Petri nets and develop its theory, which is called bipolar synchronization schemes (bp schemes).
64 citations
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TL;DR: An upper bound is given for the complexity of the Karp-Miller decision procedure for the Finite Containment Problem for pairs of Petri nets; the procedure is shown to be primitive recursive in the Ackermann function.
61 citations
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TL;DR: Description d'une nouvelle classe de Reseau de Petri appeles reseaux reguliers d'etiquetage de reseau et une methode systematique de synthetisation de reseaux normaliers est presentee.
Abstract: Description d'une nouvelle classe de Reseau de Petri appeles reseaux reguliers Discussion de quelques proprietes graphiques des variants et invariants Le concept d'etiquetage de reseau est introduit et une methode systematique de synthetisation de reseaux reguliers est presentee
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13 Dec 1984TL;DR: In this article, the authors present an introduction to the theory of Petri nets and present a broader sketch of the scope and contents of net theory, including applications of the theory in general.
Abstract: The aim of this paper is to present an introduction to the theory of Petri nets. The subject matter of this theory is distributed systems and processes. In our presentation, we shall emphasise concepts at the expense of specific results and techniques. Applications of the theory, though many and varied, will not be dealt with here. Even in dealing with the concepts, we shall focus on those that we believe are relevant to the study of distributed systems in general (independent of the specific framework one might choose). In the concluding part, we will attempt a broader sketch of the scope and contents of net theory.
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01 Jun 1984TL;DR: This paper surveys the applicability of Petri nets for protocol, as well as for service specification and validation, and chooses the ISO Transport protocol as a significant example of the proposed design methodology.
Abstract: This paper is intended to survey the applicability of Petri nets for protocol, as well as for service specification and validation. At the specification level, different classes of nets are introduced, and emphasis is given to the modular specification of a protocol layer. At the validation level, the analysis techniques implemented in the CAD package OGIVE/OVIDE are presented, and are used in order to prove safety and progress properties of a protocol layer. Finally, the specification and validation of the ISO Transport protocol is chosen as a significant example of the proposed design methodology.
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01 Jun 1984
TL;DR: This work uses a form of Timed Petri Nets and presents a technique for symbolically deriving expressions, which describe system performance, which applies to a wide range of time delays so long as the delays satisfy a set of timing constraints.
Abstract: Petri Net models have been extended in a variety of ways and have been used to prove the correctness and evaluate the performance of communication protocols. Several extensions have been proposed to model time. This work uses a form of Timed Petri Nets and presents a technique for symbolically deriving expressions, which describe system performance. Unlike past work on performance evaluation of Petri Nets which assumes a priori knowledge of specific time delays, the technique presented here applies to a wide range of time delays so long as the delays satisfy a set of timing constraints. The technique is demonstrated using a simple communication protocol.
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26 Mar 1984
TL;DR: The key elements of the introduced approach are a symbolic interpreter for Predicate Transition Nets, and a technique for interfacing concurrent processes for distributed systems.
Abstract: This paper presents a formal description technique for distributed systems The basic choices concern Petri Nets as a modeling tool and PROLOG as a programming environment The key elements of the introduced approach are a symbolic interpreter for Predicate Transition Nets, and a technique for interfacing concurrent processes Several illustrative examples are provided
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TL;DR: It is shown that the reachability set of a marked Petri net is an effectively computable semilinear set unless the total number of tokens in a minimal circuit is decreased to 0.
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TL;DR: A new type controller based on a Petry-Net like control language named C-net is proposed and initial software development man-hour was reduced about 50% compared with relay radder diagram method.
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01 Oct 1984TL;DR: The aim of this paper is to present an introduction to the theory of Petri nets, and to attempt a broader sketch of the scope and contents of net theory.
Abstract: The aim of this paper is to present an introduction to the theory of Petri nets. The subject matter of this theory is distributed systems and processes. In our presentation, we shall emphasise concepts at the expense of specific results and techniques. Applications of the theory, though many and varied, will not be dealt with here. Even in dealing with the concepts, we shall focus on those that we believe are relevant to the study of distributed systems in general (independent of the specific framework one might choose). In the concluding part, we will attempt a broader sketch of the scope and contents of net theory.
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01 Jan 1984TL;DR: A graph model now known as Petri nets originated in C. A. Petri’s doctoral dissertation in 1962 at the University of Bonn, West Germany and spread over many parts of the world during the 1970s.
Abstract: A graph model now known as Petri nets originated in C A Petri’s doctoral dissertation (1) in 1962 at the University of Bonn, West Germany In the mid 1960s, Petri’s work was introduced in the United States, and during the 1970s it spread over many parts of the world At the time of this writing, the Europeans are most active in research and conferences on Petri nets: they have held a two-week advanced course on this subject in Hamburg, West Germany under the direction of Dr Petri in 1979(2); and held so far three workshops on applications and theory of Petri nets, one each in France (1980), West Germany (1981), and Italy (1982)(3) In this field two books, one in English(4) and the other in German,(5) are now available, and several tutorial articles(6–10) have been written A comprehensive bibliography(11) is also available and is updated periodically
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TL;DR: The methodology is based upon Petri Nets and is oriented to maximize the possibilities of control and individualization provided by CAL and may be used as a common basis for different learning strategies.
Abstract: This paper discusses a methodology for representing the subject matter for CAL dialogue. The methodology is based upon Petri Nets and is oriented to maximize the possibilities of control and individualization provided by CAL. Simple examples show how to build a content representation and how the same structure may be used as a common basis for different learning strategies. “The language of computation has become the proper dialect for discussing the basic issues of both psychology and education” (Goldstein and Papert).
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TL;DR: A design tool is proposed for the subsequent development steps of a substation control system, viz. task specification, system design, software production, and hardware implementation.
Abstract: A design tool is proposed for the subsequent development steps of a substation control system, viz. task specification, system design, software production, and hardware implementation. Process control is characterized by properties like causality, determinism, asynchronity, stochastic events, and real-time control. All control tasks can directly be expressed in terms of a subclass of Petri nets with the above mentioned properties. The formal Petri net properties guarantee well defined interfaces (supporting task sharing), limit consequences of changes (in technology or by extension) to local alterations (i.e. reusability of the unaffected parts), permit concurrent task formulation (supporting availability and response time respectively) and facilitate formal error elimination. Moreover, the system design can be mapped via software to hardware by formal procedures.
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TL;DR: A technique utilizing the reachability concept of Petri nets for the enumeration of all the trees in a graph using only vector additions on a single matrix alleviates the computational effort.
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01 Jun 1984TL;DR: This paper provides the Petri net formal specifications of three important components of the ISO transport protocol: timeout mechanism, data transfer phase and connection establishment and release phases, and extends OGIVE to allow for the checking of reception errors and state ambiguities.
Abstract: In this paper, we provide the Petri net formal specifications of three important components of the ISO transport protocol: timeout mechanism, data transfer phase and connection establishment and release phases. A validation of these component Petri net specifications is then presented, followed by a discussion of its results.The validations we conducted made use of a software tool based on OGIVE [1], which can check a given Petri net for general properties such as boundedness, properness and liveness, and designer defined structural properties using Petri net invariants.We have extended OGIVE to allow for the checking of reception errors and state ambiguities as well.
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24 Apr 1984TL;DR: The notions of normalization and abstraction of entities are introduced to refine conceptual Schemas in the framework of the ER(Entity-Relationship) model and an idea for data oriented approach to information systems design is discussed.
Abstract: Behavior analysis and modeling of entities is discussed as one of practical methods for data oriented approach to systems design. For this purpose, the notions of normalization and abstraction of entities are introduced to refine conceptual Schemas in the framework of the ER(Entity-Relationship) model. Behavior of entities, which is defined as a set of states and transactions that bring about state transitions, is analyzed and modeled using the ER model and diagrammatic techniques of Petri Nets. A formalization of behavior description, together with the notion of transaction normalization, is also proposed. Based on the behavior modeling, an idea for data oriented approach to information systems design is discussed.
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TL;DR: A technique utilizing the concept of reachability in Petri net is proposed to enumerate all the circuits of a graph using only vector additions on the columns of a single matrix.
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TL;DR: Computer networks supply distributed applications in both wide area and local area environments and need deep investigation: the communication structure among processes resident in separate computers and the management structure.
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TL;DR: The problem of composing a set of communicating finite-state machines into a single global Petri net is considered in the letter with special attention to the case of more than two processes.
Abstract: In order to model and verify systems of concurrent processes (such as those involved in communication protocols), finite-state machines and Petri nets can be used as local and global models, respectively. The problem of composing a set of communicating finite-state machines into a single global Petri net is considered in the letter with special attention to the case of more than two processes.
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TL;DR: Various extensions of the concept of Petri net are dealt with using net languages in order to compare the capabilities and limitations of various net models.