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Analysis of coal development issues with the Argonne Coal Market Model

Description: This paper describes the Argonne Coal Market (ACM) Model and its use in analyzing coal related issues. The quadratic programming framework for combining supply and demand data in an interregional model is briefly described in the first section. Supply and demand data and algorithms used in estimating coal transport and environmental control cost data are presented in the second section. The last section contains a description of previous uses of the model.
Date: January 1, 1979
Creator: Macal, C.M.
Partner: UNT Libraries Government Documents Department

Solution of mathematical programming formulations of subgame perfect equilibrium problems

Description: Mathematical programming models have been developed to represent imperfectly competitive (oligopolistic) market structures and the interdependencies of decision-making units in establishing prices and production levels. The solution of these models represents an economic equilibrium. A subgame perfect equilibrium formulation explicitly considers that each agent`s strategies depend on the current state of the system; the state depends solely on previous decisions made by the economic agents. The structure of an industry-wide model that is formulated as a subgame perfect equilibrium problem is a matrix of simultaneous mathematical programming problems, where the rows represent time periods and the columns represent agents. This paper formally defines the subgame perfect equilibrium problem that includes mathematical programs for agent decision problems, and it characterizes the feasible space in a way that is conducive to the solution of the problem. The existence of equilibrium solutions on convex subspaces of the feasible region is proved, and this set is shown to contain the subgame perfect equilibrium solutions. A procedure for computing equilibrium solutions and systematically searching the subspaces is illustrated by a numerical example.
Date: February 12, 1992
Creator: Macal, C. M. & Hurter, A. P.
Partner: UNT Libraries Government Documents Department

Simulation and real-time optimal scheduling: a framework for integration

Description: Traditional scheduling and simulation models of the same system differ in several fundamental respects. These include the definition of a schedule, the existence of an objective function which orders schedules and indicates the performance of a given schedule according to specific criteria, and the level of fidelity at which the items are represented and processed through he system. This paper presents a conceptual, object-oriented, architecture for combining a traditional, high-level, scheduling system with a detailed, process- level, discrete-event simulation. A multi-echelon planning framework is established in the context of modeling end-to-end military deployments with the focus on detailed seaport operations.
Date: February 1, 1997
Creator: Macal, C.M.; Nevins, M.R.; Williams, M.K. & Joines, J.C.
Partner: UNT Libraries Government Documents Department

3D visualization of port simulation.

Description: Affordable and realistic three dimensional visualization technology can be applied to large scale constructive simulations such as the port simulation model, PORTSIM. These visualization tools enhance the experienced planner's ability to form mental models of how seaport operations will unfold when the simulation model is implemented and executed. They also offer unique opportunities to train new planners not only in the use of the simulation model but on the layout and design of seaports. Simulation visualization capabilities are enhanced by borrowing from work on interface design, camera control, and data presentation. Using selective fidelity, the designers of these visualization systems can reduce their time and efforts by concentrating on those features which yield the most value for their simulation. Offering the user various observational tools allows the freedom to simply watch or engage in the simulation without getting lost. Identifying the underlying infrastructure or cargo items with labels can provide useful information at the risk of some visual clutter. The PortVis visualization expands the PORTSIM user base which can benefit from the results provided by this capability, especially in strategic planning, mission rehearsal, and training. Strategic planners will immediately reap the benefits of seeing the impact of increased throughput visually without keeping track of statistical data. Mission rehearsal and training users will have an effective training tool to supplement their operational training exercises which are limited in number because of their high costs. Having another effective training modality in this visualization system allows more training to take place and more personnel to gain an understanding of seaport operations. This simulation and visualization training can be accomplished at lower cost than would be possible for the operational training exercises alone. The application of PORTSIM and PortVis will lead to more efficient planning overall and ultimately increase port utilization and throughput, decreasing ...
Date: June 14, 1999
Creator: Horsthemke, W. H.; Macal, C. M. & Nevins, M. R.
Partner: UNT Libraries Government Documents Department

PORTSIM: An object-oriented port simulation

Description: The development of an object-oriented port simulation (PORTSIM) that addresses military mobility issues will be described, with a brief description of the tool selection process. This system provides users with (1) a graphical user interface, (2) the ability to simulate military units through a specified port, with each individual cargo item (i.e. piece of equipment) represented, (3) utilization statistics for all port resources e.g. gates, staging areas, berths, inspectors, and material handling equipments, (4) utilization statistics for ships that arrive at the port, and (5) a graphical dynamic animation that allows for identification of bottlenecks and facilitates the playing of what-if scenarios to maximize throughput. Cargo is simulated from the time it arrives at a gate or end ramp to the time it is loaded onto a ship. Animation is directly integrated with the simulation to allow for modifications to the scenario while the simulation is running and to have the new parameters used from that point forward in time. The simulation is flexible and allows for multiple cargo types (breakbulk, container, and roll-on/roll-off) and multiple ship types.
Date: July 1, 1995
Creator: Nevins, M.R.; Macal, C.M. & Joines, J.
Partner: UNT Libraries Government Documents Department

Simulation of transportation movements over constrained infrastructure networks

Description: The Enhanced Logistics Intra-Theater Support Tool (ELIST) is a simulation-based decision support system that evaluates a military deployment plan at the theater level for transportation and logistical feasibility. ELIST includes a discrete-event, time-stepped simulation kernel written in C, an object-oriented database written in Prolog, and a set of knowledge-bases that describe various operations, such as throughput capacity of ports, based on the attributes of the relevant objects. In the course of its development, ELIST has been used to support various planning activities.
Date: July 1, 1995
Creator: Macal, C.M.; Van Groningen, C.N. & Braun, M.D.
Partner: UNT Libraries Government Documents Department

Proc. of the Workshop on Agent Simulation : Applications, Models, and Tools, Oct. 15-16, 1999

Description: The many motivations for employing agent-based computation in the social sciences are reviewed. It is argued that there exist three distinct uses of agent modeling techniques. One such use--the simplest--is conceptually quite close to traditional simulation in operations research. This use arises when equations can be formulated that completely describe a social process, and these equations are explicitly soluble, either analytically or numerically. In the former case, the agent model is merely a tool for presenting results, while in the latter it is a novel kind of Monte Carlo analysis. A second, more commonplace usage of computational agent models arises when mathematical models can be written down but not completely solved. In this case the agent-based model can shed significant light on the solution structure, illustrate dynamical properties of the model, serve to test the dependence of results on parameters and assumptions, and be a source of counter-examples. Finally, there are important classes of problems for which writing down equations is not a useful activity. In such circumstances, resort to agent-based computational models may be the only way available to explore such processes systematically, and constitute a third distinct usage of such models.
Date: October 4, 2000
Creator: Macal, C. M., ed. & Sallach, D., ed.
Partner: UNT Libraries Government Documents Department

Adding the infrastructure class hierarchy to the EXHORT framework for object-oriented deployment simulations.

Description: One of the objectives of the U.S. Department of Defense is to standardize all classes used in object-oriented deployment simulations by developing a standard class attribute representation and behavior for all deployment simulations that rely on an underlying class representation. The EXtensive Hierarchy and Object Representation for Transportation Simulations (EXHORT) is a class framework composed of two hierarchies that together constitute a standard and consistent class attribute representation and behavior that could be used directly by a large set of deployment simulations. The first hierarchy, the Transportation Class Hierarchy (TCH), was submitted to the Army Modeling and Simulation Office's (AMSO) Army Standards Repository in 1999 and presented at the Fall Simulation Interoperability Workshop in the same year. The second hierarchy, the Infrastructure Class Hierarchy (ICH), describes the encapsulation of the rest of the defense transportation system and is the primary focus of this paper. The entire EXHORT framework lets deployment simulations use the same set of underlying class data, ensures transparent exchanges, reduces the effort needed to integrate simulations, and permits a detailed analysis of the defense transportation system.
Date: July 19, 2002
Creator: Burke, J. F.; Van Groningen, C.; Bragen, M. & Macal, C. M.
Partner: UNT Libraries Government Documents Department

ELIST (the Enhanced Logistics Intra-Theater Support Tool), a tool for analyzing theater movement constraints

Description: ELIST was conceived to allow for the detailed analysis of logistical deployment plans while simplifying the initial data entry and reducing the time required for a complete analysis. ELIST allows users to build hierarchical theater infra-structure networks (airports, seaports, road, rail, pipeline) using a graphical interference, perform discrete event simulations of deployment plans ({open_quotes}scenarios{close_quotes}) which are developed on standard military planning systems, and analyze the results using textual, tabular, and graphical output at various levels of detail.
Date: February 1, 1995
Creator: Van Groningen, C. N.; Macal, C. M. & Braun, M. D.
Partner: UNT Libraries Government Documents Department

PORTSIM v.4.3 : user's manual.

Description: This manual documents the capabilities and functions of the Port Simulation (PORTSIM) Model, Version 4.3, which operates on Windows NT 4.0 or Windows 2000. Step-by-step procedures for using PORTSIM are provided. PORTSIM is a discrete-event simulation model that allows for a comprehensive analysis of all critical seaport operations for embarkation. It is applicable to ports worldwide. This simulation system addresses the complexities of port operations and gives you a way to measure the desirability of any given plan of action. PORTSIM models all cargo items, ships, and port infrastructure resources as individual objects. A typical scenario may process more than 10,000 cargo items. Cargo is simulated from the time it arrives at a port to the time it is loaded onto a ship. Note that PORTSIM Version 4.3 models only embarkation activities. Modeling of debarkation currently is being handled under another software framework. You can use PORTSIM to specify the availability of port resources to provide the most realistic simulation possible. The simulation provides detailed information on cargo throughput and infrastructure utilization. With PORTSIM, you can simulate the movement of entire military units through a specified port. You can also selectively constrain resources or operational parameters, to identify potential bottlenecks. To support your analysis, the software provides utilization statistics for all port resources (e.g., gates, staging areas, interchange yards, berths, inspectors, and container handling equipment). Simulation results are presented in three ways. (1) During the simulation run, utilization information is presented graphically in real time as continuous display meters that can help you monitor activity and identify potential problems visually as they develop. (2) During the run, you can also view a summary screen showing the current status of transports and cargo. (3) After the run, reports and graphs showing the final results can be viewed and saved.
Date: August 16, 2001
Creator: Davidson, R. S.; VanKuiken, J. C.; Bragen, M. J.; Andrew, J. M. & Macal, C. M.
Partner: UNT Libraries Government Documents Department

Standardization of transportation classes for object-oriented deployment simulations.

Description: Many recent efforts to integrate transportation and deployment simulations, although beneficial, have lacked a feature vital for seamless integration: a common data class representation. It is an objective of the Department of Defense (DoD) to standardize all classes used in object-oriented deployment simulations by developing a standard class attribute representation and behavior for all deployment simulations that rely on an underlying class representation. The Extensive Hierarchy and Object Representation for Transportation Simulations (EXHORT) is a collection of three hierarchies that together will constitute a standard and consistent class attribute representation and behavior that could be used directly by a large set of deployment simulations. The first hierarchy is the Transportation Class Hierarchy (TCH), which describes a significant portion of the defense transportation system; the other two deal with infrastructure and resource classes. EXHORT will allow deployment simulations to use the same set of underlying class data, ensure transparent exchanges, reduce the effort needed to integrate simulations, and permit a detailed analysis of the defense transportation system. This paper describes EXHORT's first hierarchy, the TCH, and provides a rationale for why it is a helpful tool for modeling major portions of the defense transportation system.
Date: July 30, 1999
Creator: Burke, J. F., Jr.; Howard, D. L.; Jackson, J.; Macal, C. M.; Nevins, M. R. & Van Groningen, C. N.
Partner: UNT Libraries Government Documents Department