A RANKING AND SELECTION PROJECT: EXPERIENCES FROM A UNIVERSITY-INDUSTRY COLLABORATION  
 
David Goldsman
 
School of Industrial and Systems Engineering
Georgia Institute of Technology
Atlanta, GA 30332, U.S.A.
  Tracy Opicka
 
School of Industrial Engineering
Purdue University
West Lafayette, IN 47907, U.S.A.
 
 
Barry L. Nelson
 
Department of Industrial Engineering & Management Sciences
Northwestern University
Evanston, IL 60208, U.S.A.
   
 
Alan B. Pritsker
 
9032 E. Cedar Waxwing Drive
Sun Lakes, AZ 85248, U.S.A.
 
ABSTRACT
 
We describe the experiences and results from a long-term collaboration between two universities and Pritsker Corporation on a grant funded by the National Science Foundation. The goal of the joint work is to make state-of-the-art research in the area of ranking and selection available to practicing engineers and management scientists.
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SIMULATION OPTIMIZATION METHODOLOGIES  
 
  Farhad Azadivar
 
Department of Industrial and Manufacturing Systems Engineering
Kansas State University
Manhattan, KS 66506, U.S.A.
 
 
ABSTRACT
 
Simulation models can be used as the objective function and/or constraint functions in optimizing stochastic complex systems. This tutorial is not meant to be an exhaustive literature search on simulation optimization techniques. It does not concentrate on explaining well-known general optimization and mathematical programming techniques either. Its emphasis is mostly on issues that are specific to simulation optimization. Even though a lot of effort has been spent to provide a reasonable overview of the field, still there are methods and techniques that have not been covered and valuable works that may not have been mentioned.
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STOCHASTIC OPTIMIZATION AND THE SIMULTANEOUS PERTURBATION METHOD  
 
  James C. Spall
 
The Johns Hopkins University
Applied Physics Laboratory
11100 Johns Hopkins Road
Laurel, Maryland 20723-6099, U.S.A.
 
 
ABSTRACT
 
Multivariate stochastic optimization plays a major role in the analysis and control of many real-world systems. In almost all large-scale practical optimization problems, it is necessary to use a mathematical algorithm that iteratively seeks out the solution because an analytical (closed-form) solution is rarely available. In the above spirit, the "simultaneous perturbation stochastic approximation (SPSA)" method for difficult multivariate optimization problems has been developed. SPSA has recently attracted considerable international attention in areas such as statistical parameter estimation, feedback control, simulation-based optimization, signal and image processing, and experimental design. The essential feature of SPSA¾which accounts for its power and relative ease of implementation¾is the underlying gradient approximation that requires only two measurements of the objective function regardless of the dimension of the optimization problem. This feature allows for a significant decrease in the cost of optimization, especially in problems with a large number of variables to be optimized.
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ADVANCED INPUT MODELING FOR SIMULATION EXPERIMENTATION  
 
  Bruce Schmeiser
 
School of Industrial Engineering
Purdue University
West Lafayette, IN 47907-1287, U.S.A.
 
 
ABSTRACT
 
We discuss ideas useful to simulation practitioners when specifying the probability models used to represent stochastic behavior. Emphasis is on situations in which the classical simple models are inadequate. After discussing some general modeling issues, we consider univariate distributions, nonnormal random vectors and time series, and nonhomogeneous Poisson processes.
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INPUT MODELS FOR SYNTHETIC OPTIMIZATION PROBLEMS  
 
  Charles H. Reilly
 
Department of Industrial Engineering and Management Systems
University of Central Florida
P.O. Box 162450
Orlando, Florida 32816, U.S.A.
 
 
ABSTRACT
 
In this paper, we describe and discuss alternative input models for the coefficients in synthetic optimization problems. Synthetic, or randomly generated, problems are often used in computational studies to establish the efficacy of solution methods or to facilitate comparative evaluations of solution methods. The selection of an input model for the coefficients in synthetic optimization problems is important because such a selection may affect the outcome of a computational study. Understanding how an assumed input model affects the characteristics of test problems can assist researchers in their efforts to accurately quantify and interpret the performance of solution methods.
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PARALLEL AND DISTRIBUTED SIMULATION  
 
  Richard M. Fujimoto
 
College of Computing
Georgia Institute of Technology
Atlanta, GA 3033, USA
 
 
ABSTRACT
 
This tutorial gives an introduction to parallel and distributed simulation systems. Issues concerning the execution of discrete-event simulations on parallel and distributed computers either to reduce model execution time or to create geographically distributed virtual environments are covered. The emphasis of this tutorial is on the algorithms and techniques that are used in the underlying simulation executive to execute simulations on parallel and distributed computing platforms.
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SIMULATION IN AN OBJECT-ORIENTED WORLD  
 
  Jeffrey A. Joines
Stephen D. Roberts

 
Department of Industrial Engineering
Campus Box 7906
North Carolina State University
Raleigh, NC 27695-7906, U.S.A.
 
 
ABSTRACT
 
An object-oriented simulation (OOS) consists of a set of objects that interact with each other over time. This pa-per provides a presentation of OOS design elements by contrasting OOS with its procedural counterparts. The elements of component technology is addressed along with the important issue of composition (components) versus inheritance that distinguishes object-based from object-oriented languages.
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SIMULATION: TECHNOLOGIES IN THE NEW MILLENNIUM  
 
  Wayne J. Davis
 
General Engineering
University of Illinois at Urbana-Champaign
Urbana, Illinois 61801
 
 
ABSTRACT
 
This paper first addresses future simulations needs from a generic point of view and then from the viewpoint of major stakeholders within the simulation community. These stakeholders include the simulation software developer/ vendor, the corporate end user, the government end-user, the researcher and the educator. We then describe or outline the set of capabilities that will be needed to design and manage future systems, and also the limitations of the current simulation tools in meeting these needs. Finally, we conjecture about the kind of simulation-based design and planning capabilities that might exist in future manufacturing systems.
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VERIFICATION AND VALIDATION:
WHAT IMPACT SHOULD PROJECT SIZE AND COMPLEXITY
HAVE ON ATTENDANT V&V ACTIVITIES AND SUPPORTING INFRASTRUCTURE?  
 
  Panel Presentation
 
 
Co-Chair and Moderator
 
James D. Arthur
 
The Department of Computer Science
Virginia Tech
Blacksburg, VA 24061, USA
  Co-Chair Panel Member and Respondent
 
Robert G. Sargent

 
The Department of Electrical Engineering and Computer Science
Syracuse University
Syracuse, NY 13244, USA
   
 
Panel Members and Respondents
 
 
James B. Dabney
 
AverStar, Inc.
100 Hercules, Suite 300
Houston, Texas 77058, USA
Averill M. Law
 
Averill M. Law & Associates
PO Box 40996
Tucson, AZ 85717, USA
John D. (Jack) Morrison
 
PO Box 1663, MS F602
Los Alamos, NM 87545, USA
 
ABSTRACT
 
The size and complexity of Modeling and Simulation (M&S) application continue to grow at a significant rate. The focus of this panel is to examine the impact that such growth should be having on attendant Verification and Validation (V&V) activities. Two prominent considerations guiding the panel discussion are:
  1. Extending the current M&S development objectives to include quality characteristics like maintainability, reliability, and reusability -- the current modus operandi focuses primarily on correctness, and
  2. Recognizing the necessity and benefits of tailoring V&V activities commensurate with the size of the project, i.e., one size does not fit all.
In this paper we provide six questions and four sets of responses to those questions. These questions and responses are intended to foster additional thought and discussion on topics crucial to the synthesis of quality M&S applications.
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