Model Name: World Dynamics
Citation: Jay W. Forrester (1971) World Dynamics. Cambridge, MA: Wright-Allen Press
Source: Standard Vensim distribution
Units balance: Yes
Format: Vensim
Model Name: World Dynamics
Citation: Jay W. Forrester (1971) World Dynamics. Cambridge, MA: Wright-Allen Press
Source: Standard Vensim distribution
Units balance: Yes
Format: Vensim
Model Name: The Energy Transition and the Economy: A System Dynamics Approach
Citation: John D. Sterman, 1981. PhD Dissertation, MIT Sloan School of Management
Source: Replicated by Miguel Vukelic (a heroic effort)
Units balance: Yes
Format: Vensim (Contains data variables and thus requires an advanced version or the free Model Reader)
Illustrations of a ‘Normal’ (first order) Outflow, a Delay Outflow, and a Fixed Delay Outflow
LEARN_comparison_of_delay_n_and_delay_fixed_etc_RGD (Vensim .vmf)
Contributed by Bruce Skarin
Introduction
This model is the product of my Major Qualifying Project (MQP) for my Bachelors degree in the field of system dynamics at Worcester Polytechnic Institute. There were two goals to this project:
1) To develop a model that reasonably simulates the historic attacks by the al-Qaida terrorist network against the United States.
2) To evaluate the usefulness of the model for developing public understanding of the terrorism problem.
The full model and report are available on my website.
Reference Mode
The reference mode for this model was the escalation of attacks linked to al-Qaida against the U.S., as shown below. The data for this chart is available through this Google Document.
Causal View of the Model
Below is the causal diagram of the primary feedback loops in the model.
Online Story Model
There is an online story version that explains the primary model structure as well as complete iThink and Vensim models on my MQP page.
Model Name: payments, penalties, and environmental ethic
Citation: Dudley, R. 2007. Payments, penalties, payouts, and environmental ethics: a system dynamics examination Sustainability: Science, Practice, & Policy 3(2):24-35. http://ejournal.nbii.org/archives/vol3iss2/0706-013.dudley.html.
Source: Richard G. Dudley
Copyright: Richard G. Dudley (2007)
License: Gnu GPL
Peer reviewed: Yes (probably when submitted for publication?)
Units balance: Yes
Format: Vensim
Target audience: People interested in the concept of payments for environmental services as a means of improving land use and conservation of natural resources.
Questions answered: How might land users’ environmental ethic be influenced by, and influence, payments for environmental services.
Software: Vensim
Submitted by Richard Dudley:
Models in the Special Issue of the System Dynamics Review on Environmental and Resource Systems, Andrew Ford & Robert Cavana, Editors. System Dynamics Review, Volume 20, Number 2, Summer of 2004.
See the following web site for article summaries and downloadable models described in this special issue: http://www.wsu.edu/~forda/SIOpen.html