Process Interaction World View Research Articles

Defining hybrid hierarchical models in πHYFLOW

Defining hybrid hierarchical models in <i>π</i>H<scp>Y</scp>F<scp>LOW</scp>

π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow: formalism, semantics, and applications

Simulation models have been described using different perspectives, or worldviews. In the process interaction world view (PI), every entity is modeled by a sequence of actions describing its life cycle, offering a comprehensive model that groups the events involving each entity. In this paper we describe π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow, a formalism for representing hybrid models using a set of communicating processes. This set is dynamic, enabling processes to be created and destroyed at runtime. Processes are encapsulated into π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow base models and communicate through shared memory. π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow, however, can guarantee modularity by enforcing that models can only communicate by input and output interfaces. π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow extends current PI approaches by providing support for HyFlow concepts of sampling and dense (continuous) outputs, in addition to the more traditional event-based communication. Likewise HyFlow, π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow is a modeling & simulation formalism driven by expressiveness and performance analysis. We present π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow semantics, and several applications to illustrate π\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pi $$\\end{document}HyFlow ability to describe a diversity of systems.

The unified process interaction worldview

ABSTRACT The process interaction worldview (PI) provides a description of a simulation model based on the life cycles of its entities. PI has traditionally been described under two perspectives: active resource and active transaction. While many simulation languages support the active transaction approach, the active resource has generally been adopted by M&S formalisms aimed to support modular models. In this paper we introduce the Unified Process Interaction Worldview (UPI) as a representation enabling the benefits of both active resource and active transaction perspectives. UPI is based on HyFlow, a formalism for representing hybrid systems using the process interaction worldview. To show UPI capabilities, we provide a simplified model of an oven with unbounded capacity. The solution of the ordinary differential equations (ODEs) describing oven and inside items temperatures, is computed by exponential time differentiating (ETD) integrators that are also represented in the HyFlow formalism.

Ascertaining Important Features of the JAPROSIM Simulation Library

This paper describes important features of JAPROSIM, a free and open source simulation library implemented in Java programming language. It provides a framework for building discrete event simulation models. The process interaction world view adopted by JAPROSIM is discussed. We present the architecture and major components of the simulation library. In order to ascertain important features of JAPROSIM, examples are given. Further motivations are discussed and suggestions for improving our work are given.

Agent-based Simulation with Process-interaction Worldview

Agent-based Simulation with Process-interaction Worldview

PSML: parallel system modeling and simulation language for electronic system level

System-level description languages in electronic system level are domain-specific sequential simulation languages using the shared-everything model in discrete-event modeling and simulation terminology. They implement sequential process-interaction worldview to take advantage of event partitioning for ease of programming and modularity. Therefore, their reference simulators can only be executed on a single physical core. Fast and accurate simulation is highly desirable for efficient and effective system design due to the ever-increasing complexity of embedded and cyber physical systems. Parallel discrete-event simulation (PDES) is the main technique to solve this problem for large-scale system-level models. PDES works based on state space partitioning by using the so-called logical process worldview. This paper proposes parallel system modeling and simulation language (PSML), along with its formalized distributed parallel simulation kernel, that provides execution of hardware models in order to improve simulation speed significantly. It will be shown that the proposed framework results in linear, super-linear speedups ranging from 11 × to 32 × for large-scale, complex PSML models in comparison with the SystemC reference simulator on a 12-core host.

ManPy: an open-source software tool for building discrete event simulation models of manufacturing systems

In this paper, we present a new open-source OS software library for building discrete event simulation objects with focus on manufacturing environments. ManPy stands for 'Manufacturing in Python' but employs a generic approach that can be extended to other types of business processes such as services, logistics and supply chain management. It is written in Python and makes use of the SimPy library to implement a process interaction world view. The goal in developing ManPy is to provide an expandable OS layer of well-defined manufacturing objects, which can be used by users with multiple levels of expertise in discrete event simulation, namely, a super user and an industrial engineer. This object repository follows a structured architecture, allowing developers to extend it, exchange ideas and methodologies, with the goal of forming an OS community. We explain how ManPy is developed on SimPy, present its architecture and give examples of its utilization. We also give insight of how this work is planned to progress in order to attract software developers, modellers and practitioners in an OS community. Copyright © 2015 John Wiley & Sons, Ltd.

Yet Another Java Based Discrete-Event Simulation Library

JAPROSIM is a well designed library, free and open source that adopts the popular process-interaction worldview. It is implemented in Java programming language allowing deep access to its powerful features and can serve as a basis for the development of dedicated object- oriented simulation environments. The paper presents architecture and major components of the library. The process-interaction world view adopted by JAPROSIM is discussed. A modeling example is given in order to highlight JAPROSIM capabilities. Important features of JAPROSIM are summarized and suggestions for improving our work are given.

Stack-free process-oriented simulation

The process interaction world view is widely used in the general simulation community for its expressive power, and is supported by most modern simulation languages. In parallel discrete event simulation, however, its use remains comparatively rare due to the perceived inefficiency (and difficulty) of parallel implementations.We present a new implementation strategy for parallel process-oriented simulation languages. This innovative, semantics-based approach directly addresses two common concerns of such languages. By concentrating on the intrinsic threads of control, we avoid the proliferation of simulation objects (and their associated costs) that might result from a naive translation. More fundamentally, the primary costs associated with process-oriented languages -- those of context switching between stacks and, in an optimistic setting, of saving the state of these stacks -- are entirely eliminated since our explicit use of continuations avoids the need for stacks in the first place. We similarly obtain cheap and natural thread preemption.

A modification of the process interaction world view

A formal definition of the process interaction world view is reviewed. A shortcoming of this world view is identified with respect to modularity and encapsulation. A modification of the world view that supports modularity and encapsulation is presented, and its advantages are discussed. It is shown how some recent process-oriented simulation languages support this modified world view. The impact of this modification on parallel simulation is discussed, and the modified world view is briefly compared to the use of object-oriented simulation modeling.

COSMOS: A simulation language for continuous, discrete and combined models

COSMOS is a new simulation language for description of continuous, discrete or combined continuous/discrete models. For continuous models, the COSMOS language definition constitutes a superset of CSSL with many additional structuring elements being incorporated, e.g. for convenient modelling of piecewise continuous models and variable structure systems. Discrete models are coded according to the process interaction world view. The design of the language constructs makes it possible to write simulation programs in accordance with modem software engineering methodology. The model and experiment description, for example, are totally separated. In addition, models can be separated into submodels.