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193
Synchronous data flow
, 1987
"... Data flow is a natural paradigm for describing DSP applications for concurrent implementation on parallel hardware. Data flow programs for signal processing are directed graphs where each node represents a function and each arc represents a signal path. Synchronous data flow (SDF) is a special case ..."
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Cited by 621 (46 self)
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Data flow is a natural paradigm for describing DSP applications for concurrent implementation on parallel hardware. Data flow programs for signal processing are directed graphs where each node represents a function and each arc represents a signal path. Synchronous data flow (SDF) is a special case of data flow (either atomic or large grain) in which the number of data samples produced or consumed by each node on each invocation is specified a priori. Nodes can be scheduled statically (at compile time) onto single or parallel programmable processors so the runtime overhead usually associated with data flow evaporates. Multiple sample rates within the same system are easily and naturally handled. Conditions for correctness of SDF graph are explained and scheduling algorithms are described for homogeneous parallel processors sharing memory. A preliminary SDF software system for automatically generating assembly language code for DSP microcomputers is described. Two new efficiency techniques are introduced, static buffering and an extension to SDF to efficiently implement conditionals.
Verification on Infinite Structures
, 2000
"... In this chapter, we present a hierarchy of infinitestate systems based on the primitive operations of sequential and parallel composition; the hierarchy includes a variety of commonlystudied classes of systems such as contextfree and pushdown automata, and Petri net processes. We then examine the ..."
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Cited by 91 (2 self)
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In this chapter, we present a hierarchy of infinitestate systems based on the primitive operations of sequential and parallel composition; the hierarchy includes a variety of commonlystudied classes of systems such as contextfree and pushdown automata, and Petri net processes. We then examine the equivalence and regularity checking problems for these classes, with special emphasis on bisimulation equivalence, stressing the structural techniques which have been devised for solving these problems. Finally, we explore the model checking problem over these classes with respect to various linear and branchingtime temporal logics.
Automatic synthesis of burstmode asynchronous controllers
, 1995
"... Asynchronous design has enjoyed a revival of interest recently, as designers seek to eliminate penalties of traditional synchronous design. In principle, asynchronous methods promise to avoid overhead due to clock skew, worstcase design assumptions and resynchronization of asynchronous external inp ..."
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Cited by 75 (10 self)
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Asynchronous design has enjoyed a revival of interest recently, as designers seek to eliminate penalties of traditional synchronous design. In principle, asynchronous methods promise to avoid overhead due to clock skew, worstcase design assumptions and resynchronization of asynchronous external inputs. In practice, however, many asynchronous design methods suffer from a number of problems: unsound algorithms (implementations may have hazards), harsh restrictions on the range of designs that can be handled (singleinput changes only), incompatibility with existing design styles and inefficiency in the resulting circuits. This thesis presents a new locallyclocked design method for the synthesis of asynchronous controllers. The method has been automated, is proven correct and produces highperformance implementations which are hazardfree at the gatelevel. Implementations allow multipleinput changes and handle a relatively unconstrained class of behaviors (called "burstmode" specifications). The method produces statemachine implementations with a minimal or nearminimal number of states. Implementations can be easily built in such common VLSI design styles as gatearray, standard cell and fullcustom. Realizations typically have the latency of
An introduction to asynchronous circuit design
 THE ENCYCLOPEDIA OF COMPUTER SCIENCE AND TECHNOLOGY
, 1997
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Petri Net Modelling of Biological Networks
 Briefings in Bioinformatics, 8(4):210 – 219
, 2007
"... Mathematical modelling is increasingly used to get insights into the functioning of complex biological networks. In this context, Petri nets (PNs) have recently emerged as a promising tool among the various methods employed for the modelling and analysis of molecular networks. PNs come with a series ..."
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Cited by 67 (3 self)
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Mathematical modelling is increasingly used to get insights into the functioning of complex biological networks. In this context, Petri nets (PNs) have recently emerged as a promising tool among the various methods employed for the modelling and analysis of molecular networks. PNs come with a series of extensions, which allow different abstraction levels, from purely qualitative to more complex quantitative models.Noteworthily, each of these models preserves the underlying graph, which depicts the interactions between the biological components. This article intends to present the basics of the approach and to foster the potential role PNs could play in the development of the computational systems biology.
Decidability of Model Checking for InfiniteState Concurrent Systems
 Acta Informatica
"... We study the decidability of the model checking problem for linear and branching time logics, and two models of concurrent computation, namely Petri nets and Basic Parallel Processes. 1 Introduction Most techniques for the verification of concurrent systems proceed by an exhaustive traversal of the ..."
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Cited by 64 (1 self)
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We study the decidability of the model checking problem for linear and branching time logics, and two models of concurrent computation, namely Petri nets and Basic Parallel Processes. 1 Introduction Most techniques for the verification of concurrent systems proceed by an exhaustive traversal of the state space. Therefore, they are inherently incapable of considering systems with infinitely many states. Recently, some new methods have been developed in order to at least palliate this problem. Using them, several verification problems for some restricted infinitestate models have been shown to be decidable. These results can be classified into those showing the decidability of equivalence relations [8, 9, 24, 26], and those showing the decidability of model checking for different modal and temporal logics. In this paper, we contribute to this second group. The model checking problem has been studied so far for three infinitestate models: contextfree processes, pushdown processes, and...
An Efficient Algorithm for Aggregating PEPA Models
 IEEE Transactions on Software Engineering
, 1999
"... Performance Evaluation Process Algebra (PEPA) is a formal language for performance modelling based on process algebra. It has previously been shown that using the process algebra apparatus compact performance models can be derived which retain the essential behavioural characteristics of the modelle ..."
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Cited by 62 (30 self)
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Performance Evaluation Process Algebra (PEPA) is a formal language for performance modelling based on process algebra. It has previously been shown that using the process algebra apparatus compact performance models can be derived which retain the essential behavioural characteristics of the modelled system. However no efficient algorithm for this derivation was given. In this paper we present an efficient algorithm which recognises and takes advantage of symmetries within the model and avoids unnecessary computation. The algorithm is illustrated by a multiprocessor example. Keywords: Performance modelling, model aggregation, performance evaluation tools, stochastic process algebras. 1 Introduction In recent years several Markovian process algebras (MPAs) have been presented in the literature. These include PEPA [1], MTIPP [2], and EMPA [3]. As with classical process algebras, these formalisms allow models of systems to be constructed which are amenable to functional or behavioural an...
Undecidable Problems in Unreliable Computations
 THEORETICAL COMPUTER SCIENCE
, 2000
"... Lossy counter machines are defined as Minsky ncounter machines where the values in the counters can spontaneously decrease at any time. While termination is decidable for lossy counter machines, structural termination (termination for every input) is undecidable. This undecidability result has f ..."
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Cited by 61 (3 self)
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Lossy counter machines are defined as Minsky ncounter machines where the values in the counters can spontaneously decrease at any time. While termination is decidable for lossy counter machines, structural termination (termination for every input) is undecidable. This undecidability result has far reaching consequences. Lossy counter machines can be used as a general tool to prove the undecidability of many problems, for example (1) The verification of systems that model communication through unreliable channels (e.g. model checking lossy fifochannel systems and lossy vector addition systems). (2) Several problems for reset Petri nets, like structural termination, boundedness and structural boundedness. (3) Parameterized problems like fairness of broadcast communication protocols.
Verification Problems in Conceptual Workflow Specifications
 Data and Knowledge Engineering
, 1996
"... Most of today's business requirements can only be accomplished through integration of various autonomous systems which were initially designed to serve the needs of particular applications. In the literature workflows are proposed to design these kinds of applications. The key tool for designin ..."
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Cited by 44 (8 self)
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Most of today's business requirements can only be accomplished through integration of various autonomous systems which were initially designed to serve the needs of particular applications. In the literature workflows are proposed to design these kinds of applications. The key tool for designing such applications is a powerful conceptual specification language. Such a language should be capable of capturing interactions and cooperation between component tasks of workflows among others. These include sequential execution, iteration, choice, parallelism and synchronisation. The central focus of this paper is the verification of such process control aspects in conceptual workflow specifications. As it is generally agreed upon that the later in the software development process an error is detected, the more it will cost to correct it, it is of vital importance to detect errors as early as possible in the systems development process. In this paper some typical verification problems in work...
Queueing Petri Nets  A Formalism for the Combined Qualitative and Quantitative Analysis of Systems
 In Proceedings of the 5th International Workshop on Petri nets and Performance Models. IEEE
, 1993
"... System analysis is often needed with respect to both qualitative and quantitative aspects. In the last decades, several formalisms have been developed that attempt to combine these aspects in one description. Present emphasis is on Stochastic Petri Nets. Amongst others, one disadvantage of these for ..."
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Cited by 42 (11 self)
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System analysis is often needed with respect to both qualitative and quantitative aspects. In the last decades, several formalisms have been developed that attempt to combine these aspects in one description. Present emphasis is on Stochastic Petri Nets. Amongst others, one disadvantage of these formalisms lies with the difficulties when describing scheduling strategies with Petri Net elements. This article describes a new version of Queueing Petri Nets (QPNs), which combines Queueing Networks and Petri Nets, aiming at eliminating these disadvantages. The new version also exhibits the modeling of timed transitions and 'timeless' queues for describing pure scheduling mechanisms. QPNs are a superset of Queueing Networks and (Generalized Stochastic) Petri Nets. The analysis of QPNs is discussed and it is shown that efficient analysis techniques from Petri Net theory can be exploited for analysis of QPNs, thus supporting the general objective of combining Petri Net and Queueing Network for...