Showing papers on "Modeling and simulation published in 1995"
01 Dec 1995
TL;DR: The Dynamic Structure Discrete Event System Specification formalism (DSDEVS) supports a new simulation paradigm, structural simulation, as opposed to conventional trajectory simulation, and supports changes in structure to the full extent, ranging from simple model/connection add/deletion to the exchange of models between network of models.
Abstract: Traditional simulation methodologies do not support changes in model structure during a simulation run. Current methodologies support only changes in model descriptive variables. Changes in structure are thus forced to be represented at the simple behavioral level. Many models are better represented at both behavioral and structural level. We present a new simulation formalism that fully supports changes in model structure and its closure under coupling. The Dynamic Structure Discrete Event System Specification formalism (DSDEVS) supports a new simulation paradigm, structural simulation, as opposed to conventional trajectory simulation. This new formalism supports changes in structure to the full extent, ranging from simple model/connection add/deletion to the exchange of models between network of models. The DELTA simulation environment, an implementation of the DSDEVS formalism, is briefly described.
73 citations
01 Aug 1995
TL;DR: The challenges include developing integrated hierarchies of models, developing adaptive decision models and other models of human behavior, developing and using new forms of uncertainty-sensitive analysis, and learning how to use DIS experiments effectively.
Abstract: Distributed interactive simulation (DIS) is a revolutionary development that is changing permanently many features of Defense Department work. The field of warfare modeling and simulation (MS it can also improve operational readiness. To achieve these potential benefits, however, will require a holistic approach, conceptual breakthroughs, and profoundly difficult model development efforts. The challenges include developing integrated hierarchies of models, developing adaptive decision models and other models of human behavior, developing and using new forms of uncertainty-sensitive analysis, and learning how to use DIS experiments effectively. >
61 citations
01 Jul 1995
TL;DR: This paper proposes a methodology for carrying out human-machine systems engineering research and in particular focuses on the development of knowledge-based support for training and aiding, characterized by the definition of knowledge requirements, a normative model structure of human- machine interaction, a knowledge architecture that implements the model and an interactive real-time simulation environment.
Abstract: This paper proposes a methodology for carrying out human-machine systems engineering research and in particular focuses on the development of knowledge-based support for training and aiding. The process is characterized by the definition of knowledge requirements, a normative model structure of human-machine interaction, a knowledge architecture that implements the model, and an interactive real-time simulation environment. The knowledge requirements largely specify the model, knowledge architecture, and simulation. The model and the knowledge architecture are the basis for the design of intelligent systems. The simulation serves as an experimental testbed that provides a feasible, safe, and effective means for exploring alternative human-machine systems designs and also facilitates technology transfer. The aim is to create an understanding of a complex work domain that forms the context for ongoing research in human-machine interaction. A specific example from satellite ground control is described. >
53 citations
Proceedings Article•
20 Aug 1995TL;DR: It is shown how nonstandard analysis overcomes challenges, provides a firm mathematical foundation, and satisfies intuitions about the behavior of hybrid systems.
Abstract: Many of today's electro-mechanical devices exhibit both continuous and discrete behavior. Modeling these hybrid systems presents special challenges for automated modeling and simulation. We show how nonstandard analysis overcomes these challenges, provides a firm mathematical foundation, and satisfies our intuitions about the behavior of hybrid systems.
45 citations
01 Jan 1995
TL;DR: In this article, a SPICE macromodel for a series-parallel resonant converter circuit is presented, which is derived from the averaged time-invariant state-space equations obtained from a Fourier transform.
Abstract: This paper presents a SPICE macromodel for a generic series-parallel resonant converter circuit. The model is derived from the averaged time-invariant state-space equations obtained from a Fourier transform. The conditions are derived under which all but the fundamental harmonic may be discarded, and the model developed based solely on the fundamental Fourier component. The single macromodel developed has a wide range of validity, and allows dc, ac, and transient analyses to be carried out in a fast, easy, and familiar manner. It also permits the converter to be incorporated alongside its control circuitry into an entire system. The simulation results from the model have been compared to results from a full simulation, and the agreement is found to be excellent, with the macromodel simulation running between 37 and 4700 times faster than the full simulation.
39 citations
13 Dec 1995
TL;DR: The second phase of algorithmic implementation of the HSML ideas and language constructs for dealing with state-event handling and model structural changes in continuous-time system components are described.
Abstract: Previous research in the area of modeling and simulation of hybrid systems led to the development of a general hybrid systems modeling language (HSML), part of which was implemented in a preliminary way by extending MATLAB. This paper describes the second phase of algorithmic implementation of the HSML ideas and language constructs for dealing with state-event handling and model structural changes in continuous-time system components. Specifically, the standard MATLAB model framework and integration algorithms are extended to support these phenomena. An example is presented to show the efficacy of these extensions within the MATLAB environment.
38 citations
TL;DR: The simulation results from the model have been compared to results from a full simulation, and the agreement is found to be excellent, with the macromodel simulation running between 37 and 4700 times faster than the full simulation.
Abstract: This paper presents a SPICE macromodel for a generic series-parallel resonant converter circuit. The model is derived from the averaged time-invariant state-space equations obtained from a Fourier transform. The conditions are derived under which all but the fundamental harmonic may be discarded, and the model developed based solely on the fundamental Fourier component. The single macromodel developed has a wide range of validity, and allows DC, AC, and transient analyses to be carried out in a fast, easy, and familiar manner. It also permits the converter to be incorporated alongside its control circuitry into an entire system. The simulation results from the model have been compared to results from a full simulation, and the agreement is found to be excellent, with the macromodel simulation running between 37 and 4700 times faster than the full simulation. >
35 citations
TL;DR: The present paper introduces a framework for collision identification in robotic tasks based on Artificial Neural Networks (ANNs) and provides fast and relatively reliable identification of the collision attributes.
Abstract: The performance of many robotic tasks depends greatly on their dynamic collision behavior. This article presents a simple method for modeling and simulating collision behavior in manipulators. The main goal in this task is to provide informative contact models. The proposed models encompasscollision attributes which comprise not only (local) contact surface properties but also structural properties of the environmental object and the manipulator. With this method, the entire dynamic and interactive motion of the manipulator with the environmental object can be simulated effectively. This is verified by our simulation results. To facilitate our investigation, a 2 DOF planar elbow manipulator with PD control is considered in the simulations as well as theoretical analysis. The simulation results are used to highlight the collision attributes which affect collision behavior and to study the effects of these attributes on the manipulator-work environment safety and performance. On the other hand, the reliable operation of intelligent robotic systems in unstructured environments requires the estimation of collision attributes before the prediction of the collision behavior can be completed. For this purpose, we introduce the notion ofcollision identification. The present paper introduces a framework for collision identification in robotic tasks. The proposed framework is based on Artificial Neural Networks (ANNs) and provides fast and relatively reliable identification of the collision attributes. The simulation results are used to generate training data for the set of ANNs. A modularized ANN-based architecture is also developed to reduce the training effort and to increase the accuracy of ANNs. The test results indicate the satisfactory performance of the proposed collision identification system.
33 citations
28 Apr 1995
TL;DR: A ferromagnetic core model based on the Jiles/Atherton algorithm [1986] is described, used to illustrate how to overcome some difficult modelling issues such as hysteresis, implicit equations, and multi-disciplinary models.
Abstract: A procedure for modeling and simulation of arbitrary nonlinear magnetics devices is presented. A set of electromagnetic primitives is described as implemented in SpectreHDL. The primitives include cores, gaps, and windings that are combined to model ferromagnetic inductors and transformers. A ferromagnetic core model based on the Jiles/Atherton algorithm [1986] is described. The model is used to illustrate how to overcome some difficult modelling issues such as hysteresis, implicit equations, and multi-disciplinary models.
29 citations
TL;DR: It is shown how transition matrices may be calculated from the service times, and the matrices associated with particular models are presented, and a representation of system performance measures, including the system time and the waiting time of customers, associated with the models.
26 citations
TL;DR: In this paper, a physical model of a self-locking kinematic pair, common for all of them, together with a mathematical model suitable for computer simulation purposes is proposed.
TL;DR: This paper finds that the inertial approximation is invalid near the diode junctions, and near the contact regions of the MESFET device, and finds a proper arrangement of terms, expressing the flux, such that the first derivative part of the system is hyperbolic, both for the hydrodynamic model and the energy transport model.
Abstract: This paper has two major goals: (1) to study the effect of the common practice of neglecting the convective terms (inertial approximation) in the hydrodynamic model in the simulation of n/sup +/-n-n/sup +/ diodes and two dimensional MESFET devices; and (2) to test analytical criteria, formulated in terms of characteristic values of the Jacobian matrix, as a method of determining the impact of first derivative perturbation terms in this model, and in related energy transport models. This characteristic value analysis can be thought of as generalizing the usual analytical solution of first order linear systems of ordinary differential equations with constant coefficients. Concerning (1), we find that the inertial approximation is invalid near the diode junctions, and near the contact regions of the MESFET device. In regard to (2), we find a proper arrangement of terms, expressing the flux, such that the first derivative part of the system is hyperbolic, both for the hydrodynamic model and the energy transport model. For the hydrodynamic model, two forms of the heat conduction term are studied, including the case of a convective term. This suggests and validates the use of shock capturing algorithms for the simulation. >
TL;DR: An eight-step approach is presented to help structure the myriad management considerations critical to an effective, goal-driven simulation, and modeling simulation's potential to stimulate ongoing organizational self-improvement and analysis is reviewed.
Abstract: Simulation modeling can be used to assess the potential value and feasibility of alternative designs, providing an objective basis for the redesign decision making inherent in BPR. This article presents an eight-step approach to help structure the myriad management considerations critical to an effective, goal-driven simulation, and reviews modeling simulation's potential to stimulate ongoing organizational self-improvement and analysis.
01 Jan 1995
TL;DR: VHDL-A Design Objectives and Rationale and Analog Modeling Using MHDL: Devices, Networks and Systems, and Modeling of Power MOSFET.
Abstract: 1. VHDL-A Design Objectives and Rationale. 2. Modeling in VHDL-A: Devices, Networks and Systems. 3. Analog Modeling Using MHDL. 4. Modeling and Simulation of Electrical and Thermal Interaction. 5. Modeling of Power MOSFET. Index.
TL;DR: The overall goals of the Center for Human Modeling and Simulation are the investigation of computer graphics modeling, animation, and rendering techniques and the relationship between human movement, natural language, and communication.
Abstract: The overall goals of the Center for Human Modeling and Simulation are the investigation of computer graphics modeling, animation, and rendering techniques. Major focii are in behavior-based animation of human movement, modeling through physics-based techniques, applications of control theory techniques to dynamic models, illumination models for image synthesis, and understanding the relationship between human movement, natural language, and communication.
06 Nov 1995
TL;DR: In this article, an update on the micro and macro-modeling of power semiconductor devices and reviews the new simulation tools and user-friendly environment that are available for the simulation of power electronic converters with special emphasis on the analysis and design of power electronics converters that are used for power supplies.
Abstract: This paper is an update on four earlier papers that were published on the subject of modeling and simulation of power electronic converters. This paper gives an update on the micro and macro-modeling of power semiconductor devices and reviews the new simulation tools and user-friendly environment that are available for the simulation of power electronic converters with special emphasis on the analysis and design of power electronic converters that are used for power supplies. The paper discusses the subject of efficient computation of steady state and the use of symbolic math analysis for the generation of design curves. An example of a novel DC power supply with low AC current distortion is chosen to illustrate the application of the symbolic math analysis. Finally the paper suggests the addition of a benchmark 12-pulse converter scheme that is generally used for high power DC supply.
01 Jan 1995
TL;DR: Therational and the main proporties of a DSblock are discussed and components between different modeling and simulation environments are discussed.
Abstract: components between different modeling and simulation environments.Therational and the main proporties of a DSblock are discussed.
Proceedings Article•
01 Dec 1995TL;DR: This work presents an integration of QSIM and QPE research as implemented in a system called QDOCS for multiple-fault diagnosis of continuous dynamic systems using QSIM models and demonstrates that QDOCs demonstrates a better balance of generality, accuracy, and efficiency than competing methods.
Abstract: Most model-based diagnosis systems, such as GDE and Sherlock, have concerned discrete, static systems such as logic circuits and use simple constraint propagation to detect inconsistencies. However, sophisticated systems such as QSIM and QPE have been developed for qualitative modeling and simulation of continuous dynamic systems. We present an integration of these two lines of research as implemented in a system called QDOCS for multiple-fault diagnosis of continuous dynamic systems using QSIM models. The main contributions of the algorithm include a method for propagating dependencies while solving a general constraint satisfaction problem and a method for verifying the consistency of a behavior with a model across time. Through systematic experiments on two realistic engineering systems, we demonstrate that QDOCS demonstrates a better balance of generality, accuracy, and efficiency than competing methods.
IBM1
TL;DR: The modeling and simulation of the Optoelectronic Technology Consortium's optical bus and the treatment of the unique requirements for the modeling of a synchronous optical bus is presented.
Abstract: The modeling and simulation of the Optoelectronic Technology Consortium's optical bus and the treatment of the unique requirements for the modeling of a synchronous optical bus is presented. Simulation results are compared to experimental measurements and conclusions drawn.
TL;DR: A new modeling method with a self-learning function is proposed by using the theories of fuzzy sets and pattern recognition to handle on-line recognition problems of some complex industrial process.
28 Apr 1995
TL;DR: A new extension of Petri nets, called Global Petri Net (GPN), is defined and it is shown how it can be used to model and simulate hybrid systems consisting of both time and event driven parts.
Abstract: Petri nets have proven themselves to be an excellent modeling and analysis tool for discrete event or asynchronous systems. On the other hand, linear system analysis uses differential and difference equations to represent time dependent or synchronous systems. A new extension of Petri nets, called Global Petri Net (GPN) provides a means for combining these two powerful tools. Here, we define this tool and show how it can be used to model and simulate hybrid systems consisting of both time and event driven parts. An example of a distributed control system is used to illustrate the GPN modeling and simulation capabilities.
IBM1
TL;DR: The electrical design of a Ceramic Multichip Module (MCM-C) CPU node for a multiprocessor parallel system has been presented and the electrical performance of the package has been evaluated through modeling and simulation using models that provide both qualitative as well as quantitative measures on signal integrity, coupled noise and switching noise.
Abstract: The electrical design of a Ceramic Multichip Module (MCM-C) CPU node for a multiprocessor parallel system has been presented. The electrical performance of the package has been evaluated through modeling and simulation using models that provide both qualitative as well as quantitative measures on signal integrity, coupled noise and switching noise that are required to guarantee proper system operation. Details on the techniques used to optimize the MCM package have also been explained in this paper. >
28 Sep 1995
TL;DR: In this paper, a computer simulation that is being developed to evaluate a controller for a triaxial shaker system has been presented, which has eight inputs and six outputs, and frequency response data from testing of the actual shaker has been used to identify parameters for the model.
Abstract: Computer modeling and simulation has been a successful tool in the design of complex control systems. This paper discusses a computer simulation that is being developed to evaluate a controller for a triaxial shaker system. The shaker system has eight inputs and six outputs. Frequency response data from testing of the actual system has been used to identify parameters for the model.
22 Oct 1995
TL;DR: This paper describes the analysis, modeling, and simulation of a notional air defense system using SMOOCHES (State Machines for Object-Oriented, Concurrent, Hierarchical Engineering Specifications).
Abstract: This paper describes the analysis, modeling, and simulation of a notional air defense system using SMOOCHES (State Machines for Object-Oriented, Concurrent, Hierarchical Engineering Specifications). SMOOCHES is an object-oriented environment based on hierarchical state machines and extensions to statecharts, specifically developed as an environment to specify, model, simulate and analyze/evaluate distributed, reactive systems.
01 Jan 1995
TL;DR: In this article, the authors describe several methods of modeling and simulating electrical and thermal effects in a single simulation, implemented by implementing the electrical, thermal and electro-thermal models in an analog hardware description language (AHDL).
Abstract: The key to a successful electro-thermal simulation is the fact that the system to be simulated is a closed system, consisting of devices exhibiting both electrical and thermal behavior. This paper describes several methods of modeling and simulating electrical and thermal effects in a single simulation. This is accomplished by implementing the electrical, thermal and electro-thermal models in an analog hardware description language (AHDL). The focus of this paper is on modeling the thermal and electrothermal portions of the network including self-heating and heat transfer between junction and ambient. An automobile seat position controller circuit is described as an example of the application of these techniques.
TL;DR: A performance estimation tool developed for modeling and simulation of open distributed energy management systems to support their design and the approach of discrete event simulation with detailed models is considered for efficient performance estimation.
Abstract: This paper describes a performance estimation tool developed for modeling and simulation of open distributed energy management systems to support their design. The approach of discrete event simulation with detailed models is considered for efficient performance estimation. The tool includes basic models constituting a platform, e.g., Ethernet, communication protocol, operating system, etc. Application softwares are modeled by specifying CPU time, disk access size, communication data size, etc. Different types of system configurations for various system activities can be easily studied. Simulation examples show how the tool is utilized for the efficient design of open distributed energy management systems.
29 Oct 1995
TL;DR: In this article, the authors presented the simulation and modelling of a low-frequency AC distribution power system for hybrid optical fiber/coaxial cable telecommunication architecture, where the goal is to study the powering requirement and the maximum loading capability of the network.
Abstract: This paper presents the simulation and modelling of a low-frequency AC distribution power system for hybrid optical fiber/coaxial cable telecommunication architecture. The objective is to study the powering requirement and the maximum loading capability of the network. The modeling of the distribution cables and the constant-power load are discussed. The voltage distribution of the network under various operating conditions is studied through computer simulation and results are reported in this paper.
01 Jan 1995
TL;DR: The experimental results on a shared memory multiprocessor indicate that the conservative parallel simulation scheme is superior to the optimistic one for this specific application and a linear speedup for large networks.
Abstract: Simulation is a tool that can be used to assess functionality and performance of communication networks and protocols. However, efficient simulation of complex communication systems is not a trivial task. In this paper, we discuss modeling and simulation of bus-based communication networks and present the results of modeling and simulation of a multigigabit/s LAN. We used parallel simulation techniques to reduce the simulation time of the LAN and implemented both an optimistic and a conservative parallel simulation scheme. Our experimental results on a shared memory multiprocessor indicate that the conservative parallel simulation scheme is superior to the optimistic one for this specific application. The parallel simulator based on the conservative scheme demonstrates a linear speedup for large networks.