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Showing papers on "Process architecture published in 1986"


Journal ArticleDOI
TL;DR: A methodology for the rapid prototyping of process control systems which is based on an original extension to classical Petri nets, and these nets are shown to be translatable into Ada program structures concerning concurrent processes and their synchronizations.
Abstract: A methodology for the rapid prototyping of process control systems which is based on an original extension to classical Petri nets is presented. The proposed nets, called PROT nets, provide a suitable framework to support the following activities: building an operational specification model; evaluation, simulation, and validation of the model; and automatic translation into program structures. PROT nets are shown to be translatable into Ada program structures concerning concurrent processes and their synchronizations. The authors illustrate this translation in detail using, as a working example, the problem of tool handling in a flexible manufacturing system.

219 citations


Book ChapterDOI
01 Jun 1986
TL;DR: The theory is confined to a restricted class of Petrinets called safe Petri nets which correspond essentially to systems that have finite state spaces.
Abstract: We give a sketch of the theory of Petri nets. The aspects that we concentrate on are the basic notions of the theory and the interplay between the structure and behaviour of distributed systems as modelled by Petri nets. The theory we present is confined to a restricted class of Petri nets called safe Petri nets which correspond essentially to systems that have finite state spaces.

119 citations


Book ChapterDOI
01 Jun 1986
TL;DR: A way of combining algebraic specifications and Petri nets for specifying parallel systems formally, where the data structure of a system is algebraically specified while its behaviour, and especially the synchronization constraints, are specified by a Petri net-like schema.
Abstract: We present a way of combining algebraic specifications and Petri nets for specifying parallel systems formally. The data structure of a system is algebraically specified while its behaviour, and especially the synchronization constraints, are specified by a Petri net-like schema. The semantics of a specification is defined as a class of coloured Petri nets.

87 citations


Journal ArticleDOI
Peter Huber1, Arne Jensen1, Li1, Leif O. Jepsen1, Kurt Jensen1 
TL;DR: A generalization of reachability trees is contributed to, which is one of the other important analysis methods known for place/transition nets.

77 citations


Proceedings ArticleDOI
07 Apr 1986
TL;DR: Applications of Petri net models in the design of simulators for flexible manufacturing systems (FMSs) and in the verification (by investigating the presence/absence of deadlock) of the logic used to design the hardware/software for controllers used in FMSs are presented.
Abstract: Petri nets have evolved into a powerful tool for analyzing asynchronous concurrent systems. In this paper we review the applications of Petri nets to FMSs. We present applications of Petri net models in the design of simulators for flexible manufacturing systems (FMSs) and in the verification (by investigating the presence/absence of deadlock) of the logic used to design the hardware/software for controllers used in FMSs.

73 citations


Journal ArticleDOI
TL;DR: A distributed microprocessor-based architecture is described and a two-level machine tool synchronization structure is presented, given in terms of Petri nets: a graphical-mathematical technique suitable for representing process parallelism and asynchronism for flexible control of machine tools in a job shop environment.

45 citations


Journal ArticleDOI
TL;DR: This paper shows how dummy transitions can be incorporated in a timed Petri net to model contingencies in the system such as machine or tool breakdown, quality deterioration, or production volume surge.

43 citations


Book ChapterDOI
08 Sep 1986
TL;DR: The way Petri Nets are used in production systems will be presented: class of nets, high level nets, net interpretation, the problem of structuration, specification and analysis...
Abstract: Petri Nets and related graphical models are actually being employed in indutry for the design and implementation of production system control. This lecture will present a short overview of this utilization, and the reasons why this tool is more convenient than other models for concurrency will be analysed. Then, the way Petri Nets are used in production systems will be presented: class of nets, high level nets, net interpretation, the problem of structuration, specification and analysis... Finally, some principles about direct implementations will be given.

39 citations


Book ChapterDOI
Kurt Jensen1
08 Sep 1986
TL;DR: Graphical work stations provide the opportunity to work — not only with textual representations of Petri nets — but also directly with the graphical representations.
Abstract: The practical use of Petri nets is — just as any other description technique — very dependent on the existence of adequate computer tools, which may assist the user to cope with the many details of a large description. For Petri nets there is a need for tools supporting construction of nets, as well as modification and analysis. Graphical work stations provide the opportunity to work — not only with textual representations of Petri nets — but also directly with the graphical representations.

28 citations


Book ChapterDOI
08 Sep 1986
TL;DR: In this paper, Petri net based models have been developped and used to specify and analyse the set of interactions which occur in distributed systems: it explains the use of these models in order to design, specify and validate the hierarchy of protocols and services which is to be dealt with when developping complex distributed systems.
Abstract: Many approaches exist for the formal description of communication and cooperation protocols, as for instance Petri nets and their extensions, abstract data types, temporal logic, process algebras and high level languages. This paper presents how Petri net based models have been developped and used to specify and analyse the set of interactions which occur in distributed systems: it explains the use of these models in order to design, specify and validate the hierarchy of protocols and services which is to be dealt with when developping complex distributed systems. As layering proves to be of prime importance, the main specificities of the design of a complex distributed system are first related to a layered architectural model such as the OSI ISO/CCITT reference model. Then, after presenting some important Petri net based models, it is shown how net approaches can be used to model and handle the interactions and the protocols which exist in such layered distributed systems. Some important tools are also reported.

25 citations


Book ChapterDOI
05 Mar 1986
TL;DR: By a number of examples it will be demonstrated how Petri nets can be applied to design and to analyze embedded systems.
Abstract: By a number of examples it will be demonstrated how Petri nets can be applied to design and to analyze embedded systems. Principles of Petri nets as a design method are discussed. Various application areas are glanced, and some relationships to other methods are sketched.

Journal ArticleDOI
TL;DR: A new class of application for the reachability equation has been proposed and an algorithm has been postulated to access the data paths between any two specified nodes in the database model.
Abstract: The authors exploit the concepts of Petri nets for the modeling of databases through a meaningful interpretation of various database structures. This has been achieved using, specifically, the reachability and conflict concepts of Petri nets. The concept of conflict has been given a mathematical interpretation to suit its applications to database structures. Starting with a network structure, a new class of application for the reachability equation has been proposed. Based upon this, an algorithm has been postulated to access the data paths between any two specified nodes in the database model. The goal is to provide useful data for the design of databases.


Journal ArticleDOI
TL;DR: A system, called MAP, is developed, which, starting from a higher level description by means of Petri Nets, produces sound sample files; the intermediate levels of representation are obtained via the CMUSIC package.
Abstract: In this paper we show how Petri Nets can be used to describe and perform musical processes. We have developed a system, called MAP, which, starting from a higher level description by means of Petri Nets, produces sound sample files; the intermediate levels of representation are obtained via the CMUSIC package. Our approach makes’ it possible to easily describe hierarchy, concurrency and causality within musical processes and to perform them via DACs.

Proceedings Article
17 Jun 1986
TL;DR: This work characterize's daughter nets, called modules, prove that it is decidable whether a net is a module and show how firing sequences and reachable markings of module, host and refined net are interrelated.
Abstract: In a hierarchic design of a Petri net a host net, which is a ”rough” model, is refined by replacing a transition by a daughter net, that simulates the transition. For the independent design of host and daughter net those daughter nets are of interest that guarantee that an arbitrary host has the same behaviour as the respective refined net. We characterize these daughter nets, called modules, prove that it is decidable whether a net is a module and show how firing sequences and reachable markings of module, host and refined net are interrelated. Our results shed some light on the problem what a homomorphism of Petri nets should be and allow the generation of live Petri nets.

Book ChapterDOI
08 Sep 1986
TL;DR: In this article, the authors consider the use of Petri nets and extensions to describe features of existing architectures and show models for look-ahead processing schemes and the cache coherence problem.
Abstract: In this paper we consider the use of Petri nets and extensions to describe features of existing architectures. Because the main attraction of Petri nets is in their ability to express synchronization and concurrency, our modelling is directed towards high-performance architectures. In particular, we show models for look-ahead processing schemes and the cache coherence problem.

Journal ArticleDOI
TL;DR: The Petri-Net-machine as mentioned in this paper is the first tool of this kind which runs on microcomputers and describes the functions and abilities of that software system, as well as its capabilities.

Journal ArticleDOI
TL;DR: A methodology to automate the design of control structures for VLSI systems is described and a set of algorithms and optimization strategies have been developed to transform such a restructed timed Petri net into microprograms.

Journal ArticleDOI
TL;DR: A Petri net approach to the automatic design of control programs which are aimed at supervision of concurrent, pipeline-like flowing processes observed in large-variety, small-lot production systems is dealt with.

01 Jun 1986
TL;DR: A dynamic means by which deadlock may be detected has been developed and an executable equivalent that will find the most overlapped ordering that will not result in deadlock, based on reachability is developed.
Abstract: A dynamic means by which deadlock may be detected has been developed. The mechanism involves a two-step process where deadlock-prone Petri Nets are identified and then execution orderings of the network are submitted to an executable equivalent that will find the most overlapped ordering that will not result in deadlock, based on reachability. In order to detect deadlock, a class of deadlock-prone Petri Nets has been defined. This class identifies the characteristics of deadlock and is realizable in Prolog. In order to develop an executable equivalent of the execution of the Petri Net, a kernel of the mathematics of the Petri Net has been defined. Based on this kernel, a Prolog equivalent has been defined.


Journal ArticleDOI
TL;DR: This paper describes a simulation program that simulates the dynamic behaviour of Petri Nets and two major analysis techniques, namely, reachability tree and matrix analysis are explored.

01 Jan 1986
TL;DR: A Petri-net model suitable for analyzing the concurrent processing of computationally complex algorithms and its application to both the description of the data/control flow of a particular algorithm, and to the general specification of theData driven architecture is presented.
Abstract: This paper presents a Petri-net model suitable for analyzing the concurrent processing of computationally complex algorithms. The decomposed operations are to be processed in a multiple processor, data driven architecture. Of particular interest is the application of the model to both the description of the data/control flow of a particular algorithm, and to the general specification of the data driven architecture. A candidate architecture is also presented.


01 Jan 1986
TL;DR: A CCS-oriented extension of the Petri net concept, called Communication System Nets, CS-nets, is introduced which incorporates a conditional action feature.
Abstract: Among the various methods for the modeling of distributed systems that currently are available, the process algebra CCS and Petri nets with extensions are of particular interest CCS contains the useful concept of synchronized communication While the theory of CCS is based on a single concept of behavioral equivalence, a variety of such concepts could be incorporated into net theory Particularly, a clear distinction can be made between the interleaving of concurrent actions and true concurrency Net theory also provides a suitable basis for the investigation of structural proprties (eg liveness) Furthermore, various reduction techniques applicable to nets compare favorably with the algebraic analysis methods of CCS In view of these arguments, a CCS-oriented extension of the Petri net concept, called Communication System Nets, CS-nets, is introduced which incorporates a conditional action feature Various behavior-preserving reduction techniques are demonstrated along with the applicability of CS-Nets to the specification and verification of distributed systems

Proceedings ArticleDOI
01 Feb 1986
TL;DR: It is shown that the behavior of enhanced free-choice bounded M-timed Petri nets with two classes of transitions, immediate and timed ones, and with exponentially distributed firing times of timed transitions, can be represented by state-transition graphs which are finite continuous-time homogeneous Markov chains.
Abstract: It is shown that the behavior of enhanced free-choice bounded M-timed Petri nets, i.e., Petri nets with two classes of transitions, immediate and timed ones, and with exponentially distributed firing times of timed transitions, can be represented by state-transition graphs which are finite continuous-time homogeneous Markov chains. Moreover, for each finite continuous-time homogeneous Markov chain there exists an enhanced free-choice bounded M-timed Petri net with the state-transition graph isomorphic to this chain. These two classes of models are thus equivalent. A straight-forward application of (enhanced) M-timed Petri nets is modelling and performance evaluation of Markovian queueing systems, and in particular closed-network models of computer systems. Simple models of interactive systems are used as an illustration of modelling. as an illustration of modelling.

Journal ArticleDOI
TL;DR: The preposed treatment for interpreted modules seems to be sufficient for studying the dynamic behaviour of any kind of the networks at different level of abstractions.

Journal ArticleDOI
TL;DR: An interactive graphics package for modeling with Petri Nets has been implemented that uses the VT-11 graphics terminal supported on the PDP-11/35 computer to draw, execute, analyze, edit and redraw a Petri Net.