The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform

Stavros Tripakis - One of the best experts on this subject based on the ideXlab platform.

  • exploring models of computation with ptolemy ii
    International Conference on Hardware Software Codesign and System Synthesis, 2010
    Co-Authors: Christopher Brooks, Stavros Tripakis
    Abstract:

    The Ptolemy project studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components. The key underlying principle in the project is the use of well-defined models of computation that govern the interaction between components. A major problem area being addressed is the use of heterogeneous mixtures of models of computation. Ptolemy II takes a component view of design, in that models are constructed as a set of interacting components. A model of computation governs the semantics of the interaction, and thus imposes an Execution-time discipline. Ptolemy II has implementations of many models of computation including Synchronous Data Flow, Kahn Process Networks, Discrete Event, Continuous Time, Synchronous/Reactive and Modal Model. This hands-on tutorial explores how these models of computation are implemented in Ptolemy II and how to create new models of computation such as a "non-dogmatic" Process Networks example and a left-to-right Execution Policy example.

  • CODES+ISSS - Exploring models of computation with ptolemy II
    Proceedings of the eighth IEEE ACM IFIP international conference on Hardware software codesign and system synthesis - CODES ISSS '10, 2010
    Co-Authors: Christopher Brooks, Edward A. Lee, Stavros Tripakis
    Abstract:

    The Ptolemy project studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components. The key underlying principle in the project is the use of well-defined models of computation that govern the interaction between components. A major problem area being addressed is the use of heterogeneous mixtures of models of computation. Ptolemy II takes a component view of design, in that models are constructed as a set of interacting components. A model of computation governs the semantics of the interaction, and thus imposes an Execution-time discipline. Ptolemy II has implementations of many models of computation including Synchronous Data Flow, Kahn Process Networks, Discrete Event, Continuous Time, Synchronous/Reactive and Modal Model. This hands-on tutorial explores how these models of computation are implemented in Ptolemy II and how to create new models of computation such as a "non-dogmatic" Process Networks example and a left-to-right Execution Policy example.

Willy Herroelen - One of the best experts on this subject based on the ideXlab platform.

  • proactive policies for the stochastic resource constrained project scheduling problem
    European Journal of Operational Research, 2011
    Co-Authors: Filip Deblaere, Erik Demeulemeester, Willy Herroelen
    Abstract:

    The resource-constrained project scheduling problem involves the determination of a schedule of the project activities, satisfying the precedence and resource constraints while minimizing the project duration. In practice, activity durations may be subject to variability. We propose a stochastic methodology for the determination of a project Execution Policy and a vector of predictive activity starting times with the objective of minimizing a cost function that consists of the weighted expected activity starting time deviations and the penalties or bonuses associated with late or early project completion. In a computational experiment, we show that our procedure greatly outperforms existing algorithms described in the literature.

  • Generating proactive Execution policies for resource-constrained projects with uncertain activity durations
    SSRN Electronic Journal, 2010
    Co-Authors: Filip Deblaere, Erik Demeulemeester, Willy Herroelen
    Abstract:

    The resource-constrained project scheduling problem involves the determination of a schedule of the project activities, satisfying the precedence relations and resource constraints while minimizing the project duration. In practice, activity durations may be subject to variability, such that a stochastic approach to the problem is more appropriate. We propose a methodology for the determination of a project Execution Policy and a vector of predictive activity starting times with the objective of minimizing a cost function that consists of the weighted expected activity starting time deviations and the penalties or bonuses associated with late or early project completion. In a computational experiment, we show that our procedure greatly outperforms existing algorithms described in the literature

Christopher Brooks - One of the best experts on this subject based on the ideXlab platform.

  • exploring models of computation with ptolemy ii
    International Conference on Hardware Software Codesign and System Synthesis, 2010
    Co-Authors: Christopher Brooks, Stavros Tripakis
    Abstract:

    The Ptolemy project studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components. The key underlying principle in the project is the use of well-defined models of computation that govern the interaction between components. A major problem area being addressed is the use of heterogeneous mixtures of models of computation. Ptolemy II takes a component view of design, in that models are constructed as a set of interacting components. A model of computation governs the semantics of the interaction, and thus imposes an Execution-time discipline. Ptolemy II has implementations of many models of computation including Synchronous Data Flow, Kahn Process Networks, Discrete Event, Continuous Time, Synchronous/Reactive and Modal Model. This hands-on tutorial explores how these models of computation are implemented in Ptolemy II and how to create new models of computation such as a "non-dogmatic" Process Networks example and a left-to-right Execution Policy example.

  • CODES+ISSS - Exploring models of computation with ptolemy II
    Proceedings of the eighth IEEE ACM IFIP international conference on Hardware software codesign and system synthesis - CODES ISSS '10, 2010
    Co-Authors: Christopher Brooks, Edward A. Lee, Stavros Tripakis
    Abstract:

    The Ptolemy project studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components. The key underlying principle in the project is the use of well-defined models of computation that govern the interaction between components. A major problem area being addressed is the use of heterogeneous mixtures of models of computation. Ptolemy II takes a component view of design, in that models are constructed as a set of interacting components. A model of computation governs the semantics of the interaction, and thus imposes an Execution-time discipline. Ptolemy II has implementations of many models of computation including Synchronous Data Flow, Kahn Process Networks, Discrete Event, Continuous Time, Synchronous/Reactive and Modal Model. This hands-on tutorial explores how these models of computation are implemented in Ptolemy II and how to create new models of computation such as a "non-dogmatic" Process Networks example and a left-to-right Execution Policy example.

Filip Deblaere - One of the best experts on this subject based on the ideXlab platform.

  • proactive policies for the stochastic resource constrained project scheduling problem
    European Journal of Operational Research, 2011
    Co-Authors: Filip Deblaere, Erik Demeulemeester, Willy Herroelen
    Abstract:

    The resource-constrained project scheduling problem involves the determination of a schedule of the project activities, satisfying the precedence and resource constraints while minimizing the project duration. In practice, activity durations may be subject to variability. We propose a stochastic methodology for the determination of a project Execution Policy and a vector of predictive activity starting times with the objective of minimizing a cost function that consists of the weighted expected activity starting time deviations and the penalties or bonuses associated with late or early project completion. In a computational experiment, we show that our procedure greatly outperforms existing algorithms described in the literature.

  • Generating proactive Execution policies for resource-constrained projects with uncertain activity durations
    SSRN Electronic Journal, 2010
    Co-Authors: Filip Deblaere, Erik Demeulemeester, Willy Herroelen
    Abstract:

    The resource-constrained project scheduling problem involves the determination of a schedule of the project activities, satisfying the precedence relations and resource constraints while minimizing the project duration. In practice, activity durations may be subject to variability, such that a stochastic approach to the problem is more appropriate. We propose a methodology for the determination of a project Execution Policy and a vector of predictive activity starting times with the objective of minimizing a cost function that consists of the weighted expected activity starting time deviations and the penalties or bonuses associated with late or early project completion. In a computational experiment, we show that our procedure greatly outperforms existing algorithms described in the literature

Jean-louis Rougier - One of the best experts on this subject based on the ideXlab platform.

  • Resilient Inter-Carrier Traffic Engineering for Internet Peering Interconnections
    IEEE Transactions on Network and Service Management, 2011
    Co-Authors: Stefano Secci, Bjarne Emil Helvik, Jean-louis Rougier
    Abstract:

    We present a novel resilient routing Policy for controlling the routing across peering links between Internet carriers. Our Policy is aimed at offering more dependability and better performance to the routing decision with respect to the current practice (e.g., hot-potato routing). Our work relies on a non-cooperative game framework, called Peering Equilibrium MultiPath (PEMP), that has been recently proposed. PEMP allows two carrier providers to coordinate a multipath route selection for critical flows across peering links, while preserving their respective interests and independence. In this paper, we propose a resilient PEMP Execution Policy accounting for the occurrence of potential impairments (traffic matrix variations, intra-AS and peering link failures) that may occur in both peering networks. We mathematically define how to produce robust equilibrium sets and describe how to appropriately react to unexpected network impairments that might take place. The results from extensive simulations show that, under a realistic failure scenario, our Policy adaptively prevents from peering link congestions and excessive route deviations after failures.

  • A Resilient Routing Policy for Peering Management
    2010
    Co-Authors: Stefano Secci, Bjarne Emil Helvik, Jean-louis Rougier
    Abstract:

    We present a novel resilient routing Policy for controlling the routing across peering links between Internet carriers. Our Policy is aimed at offering more reliability, dependability and better performance to the routing decision with respect to the current practice (e.g., hot-potato routing). Our work relies on a non-cooperative game framework, called Peering Equilibrium MultiPath (PEMP), that has been recently proposed. PEMP allows two carrier providers to coordinate a multipath route selection for critical flows across peering links, while preserving their respective interests and independence. In this paper, we propose a resilient PEMP Execution Policy accounting for the occurrence of potential impairments (traffic matrix variations, intra-AS and peering link failures) that may occurr in both peering networks. We mathematically define how to produce robust equilibrium sets and describe how to appropriately react to unexpected network impairments that might take place. The results from extensive simulations show that, under a realistic failure scenario, our Policy adaptively prevents from peering link congestions and excessive route deviations after failures.