Showing papers on "Discrete event dynamic system published in 1978"

Event manipulation for discrete simulations requiring large numbers of events

Abstract: The event-manipulation system presented here consists of two major parts. The first part addresses the familiar problem of event scheduling efficiency when the number of scheduled events grows large. The second part deals with the less apparent problem of providing efficiency and flexibility as scheduled events are accessed to be executed. Additional features and problems dealt with include the proper handling of simultaneous events; that certain events must be created, scheduled, and executed at the same points in simulated time; that infinite loops caused by the concatenation of such “zero-time” events are possible and must be diagnosed; that maintaining various event counts is practical and economical; and that a capability for handling “time-displaceable” events is desirable and possible.

Feedback Stackelberg strategy for M-level hierarchical games

Abstract: A multilevel feedback Stackelberg strategy is formulated for systems with M players arranged in a linear hierarchy of decision making. For a linear-quadratic discrete-time game, sufficient conditions are given for existence and uniqueness of solution.

Discrete event simulation programming

Abstract: This chapter reviews discrete event simulation models. Discrete event simulation models are used to study performance characteristics of simple waiting line systems and of more complex queuing systems. All discrete event simulation models describe the way by which customers or entities flow through a system over time. A basic premise that applies to such models is that all changes in the state of a system are instantaneous changes at specific points in time. Such changes are discrete as opposed to continuous, and the occasion of such a change can be termed as an event, thereby, explaining the term discrete event simulation. The two main advantages of adopting a discrete event philosophy when a complex system is to be modeled, studied, and analyzed are (1) that all discrete event models can be synthesized from a set of basic building blocks or components and (2) that computer languages are available to allow the analyst to put together simulation models based on these building blocks. Several different special purpose computer simulation languages such as GPSS or SIMSCRIPT are available. Such languages are particularly useful to describe certain classes of simulation problems. However, they lack the versatility of general purpose languages such as FORTRAN.

On Structure Identification of Discrete Time Systems

Abstract: In a typical modelling situation, we deal with systems, for which only partial data are available to construct a system model. We often restrict our attention to a subclass of all possible models, constrained, for example, by the necessity to cut down the search space to be explored.

Design of a simple model descriptor and its translator for discrete event systems

Abstract: Simulation and modeling have been instruments for the study of real systems by researchers in various disciplines. Only recently has there been an effort towards formalization based on general and mathematical systems theory(]). The field of simulation methodology is growing. It goals are best realized when the methodology can be translated into software for use in digital computers. At present too little help is being offered by the computer in the development of models, simulation program generation, and model validation. Zeigler has developed certain conceptual and mathematical theories for guiding the practice of modeling as well as design of software tools to assist in this practice(2). His approach uses system-theoretic concepts with automata theory to formalize the structure and behaviour of models. Based on tb~t approach a strong case has been presented for development of software to translate a model description into some conventional simulation language with facilities for model construction, manipulation, documentation, validation, generation of simulation programs, and algorithmic verification through automatic submission of programs(3). This paper presents the development of a simple description language based upon the structure of discrete event systems as a six tuple consisting of inputs, outputs, states, transition functions, output functions, and a time base(2). The model description is checked for consistency in terms of valid state transitions and is translated into a standardized representation. The representation so generated is translated into a simulation program in the simulation language Simscript. A modular approach is taken in the development of the descriptor and program translator in order to facilitate easy addition of features to the system. DESCRIPTOR The descriptor is a modular structure for model definition based upon Toacher's informal description of models(4). The descriptor has been designed to a great extent with Simscript as the target language of the translator in mind. The descriptor consists of six major sections, i) Componentsofthe model, 2) Descriptive variables for the components, 3) Component interaction, 4) Output facilities, 5) Terminal conditions, 6) Initializations of variables. The sections are recognized with labels ending with : , and the statements within the model are terminated by ; . Any comments in the system are specified within " ......... ". The set of model structures has free format. The generalized specification is given as follows: SYSTEM STRUCTURE FOR: