Reading Supporting Material

Supporting Material files can be found by clicking on the appropriate link in the Paper Index (index.htm) found on the conference website. Papers are listed alphabetically by the last name of the primary author.

      Viewing/Opening/Reading the Supporting Material:

Some of these files are plain text files or presentations which are in widely accessible formats such as .doc, .ppt, .pdf, etc., but others are model files, which need to be viewed using the appropriate system dynamics modeling software. Below, find information on how to access freeware/demo/trial versions from several system dynamics software manufacturers. Follow the links within the descriptions below to the software needed to view the files.

In following chart, find the three-letter extension of the file name, then the software you need to view the file.

File Name Extension

Software Needed

.itm, .stm

iThink, STELLA*


Powersim Studio



.vmf, .vpa, .vpm, and .mdl


*ithink and STELLA can each be used to open both .itm and .stm files.


STELLA/ithink by isee systems:

This link will navigate you to the FREE isee Player. The isee Player lets you view, run, print and share both STELLA and iThink models. Available in both Windows and Macintosh versions, the isee Player allows exploration of all model layers - map, model, equation, and interface, and never "times out."


Powersim Studio by Powersim Solutions:

Powersim Studio 7 Express is a free and fully-functional 60-day trial version of Powersim Studio 7 Enterprise edition, our SAP-certified platform for building, analyzing and sharing business simulations in a corporate environment. Studio 7 contains an array of new and exciting features, including calendar-independent simulations, new functions for prioritization and resource allocation, etc., improved dataset and SAP BI connectivity, scatter graphs, updated wizards and tutorials and more. Note that a Studio 7 installation will automatically replace any previous version of Studio.

Vensim by Ventana Systems:

The Vensim Model Reader can be used to open Vensim models which are files with extension .vmf, .vpm or .vpa. This is free software which will allow you to view and simulate models changing the assumptions but not model structure. Many models (.vmf, .vpa, .vpm, and .mdl) can also be opened using Vensim PLE which is free for educational use. Both PLE and the Reader are available from:


50th Anniversary Celebration of System Dynamics           July 29 – August 2, 2007, Boston, USA