Modeling Complex Dynamic Systems with StarLogo in the Supercomputing Challenge

StarLogo is a computer modeling tool Developed at the Massachusetts Institute of Technology (MIT) Designed to enable people to build their own models of complex dynamic systems. Emphasizes “Learning by creating and observing”. Used by students, teachers, and researchers to develop a deeper understanding of the patterns and processes in the world around us. A “Forest Fire” model created with StarLogo

StarLogo is a programming language Easy-to-learn programming commands can be used to produce effective and interesting models of natural or hypothetical systems Advanced programming commands allow for more complex modeling and rich data output A list of all programming commands are available on the StarLogo website

Creating Computer Models with StarLogo Create models or simulations by writing simple rules for individual “creatures” or “agents” to follow No sophisticated mathematics or programming required Explore the behavior of complex systems The Predator, Prey, and Grass Model

Key Elements of a StarLogo Model The “Observer” program – controls the world The “Turtles” program – animates the agents The “Patches” – reveal the world’s “terrain”

An example StarLogo model Rabbits and Grass Grass grows Rabbits eat grass or die Rabbits reproduce

Using StarLogo in the Challenge The StarLogo language can be used to create models or simulations of real-life or hypothetical phenomena. Some projects can be modeled using StarLogo, others are not suitable for modeling in StarLogo. Is StarLogo appropriate for your project?

Modeling and Computational Science A model is a simplified representation of the interaction of real-world objects in a complex dynamic system. The goal is to gain an understanding of how the model’s results relate to possible real-world phenomena. Random factors built into the model and variables changed by the user cause different results to be generated when the model is run repeatedly. Models are just one component of the computational science process.

The Computational Science Process StarLogo fits in this process as the Computational Model Begin here

What are complex dynamic systems? Complex difficult-to-understand or difficult to predict Dynamic moving, changing “Complex Dynamic Systems” are collections of simple units or agents interacting in a system. Large-scale system behaviors may change, evolve, or adapt.

System structure or patterns emerge from simple interactions of its agents System structure or patterns emerge from simple interactions of its agents There is no central control – it is a decentralized system There is no central control – it is a decentralized system The system self-organizes The system self-organizes Characteristics of Complex Adaptive Systems

Some examples of Complex Adaptive Systems Global climate patterns Global climate patterns A termite mound A termite mound Highway traffic patterns Highway traffic patterns The spread of a disease in a population The spread of a disease in a population The evolution of ideas in a society The evolution of ideas in a society A food web in an ecosystem A food web in an ecosystem

How to get started with StarLogo Download StarLogo from the internet: Copy StarLogo from the CDROM provided at this conference StarLogo is a free program provided by M.I.T. or,

StarLogo Learning Resources The bookThe website

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