DSM-GIS
An application that links MapObjectsÔ to the PowersimÒ dynamic simulation modeler

The rise of component software reduces the mechanical difficulty of connecting GIS and a variety of modeling tools and environments. Sandia has recently used MapObjects and Powersim to create a single application for running dynamic simulation models (DSMs) and viewing their outputs in geographic terms.

DSMs are the tools of System Dynamics, where mental models of things and their interactions over time are formalized as Stocks, Flows, Functions, Constants, feedback loops, and other elements. The model is then run, with users observing system behavior through animated charts and other displays as model time passes. DSMs have been applied to many commercial and industrial processes, e.g. product realization, sales and marketing, human resources, etc. They have also been used to model policy issues, such as population growth, sustainable development, and resource use. DSMs in the form of Powersim and related products do not seem to have been combined with GIS, however.

Sandia has performed a series of experiments to see if GIS data and possibly displays can be combined with DSM and applied to subjects like human-induced climate change, international energy flows, and global resources. Trade studies were used to identify a rich, user-friendly, and architecturally-open DSM. Powersim was chosen for its capability and low-level OLE/OCX interface. Several GIS components were evaluated; MapObjects was selected over an initial client/server approach using ArcViewÔ . At this point, the two foundations were in place. We describe the ensuing integration process and discuss some lessons that were learned. Our prototype also illuminates a number of deeper methodological issues that are fertile ground for additional research and development.

Additional information is at: http://www.sandia.gov/gis/tech/dsmgis/Default.htm

Thomas E. Drennen
Energy Policy and Planning (6217)
Sandia National Laboratories
POB 5800, M/S 0749
Albuquerque, NM, USA 87185-0749
Telephone: 716-393-0221
FAX: 716-393-0223
Internet: tedrenn@sandia.gov

John H. Ganter
Decision Support Systems Software Engineering (6533)
Sandia National Laboratories
POB 5800, M/S 1138
Albuquerque, New Mexico, USA 87185-1138
Telephone: 505-844-1304
FAX: 505-284-3850
Internet: jganter@sandia.gov

SAND 96-2910A. This work was supported by the United States Department of Energy under Contract DE-AC04-94AL85000. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy.