two more SwarmFest talks!

[Marcus G. Daniels]

[See http://www.swarm.org/community-swarmfest-program.html for other speakers.]

Distributed Simulations using Swarm
Jorge Goic <address@hidden>
Environmental Research Institute of Michigan

The ability to run distributed simulations is useful in at least two
respects. First, it allows a modeler to partition a complex system
into manageable components that can then be run on separate
machines. This is particularly useful with agent systems in which the
agents have heavy computational loads and inter-agent communication is
relatively low. A distributed version has the potential for providing
increased performance over running the model on a single CPU. Second,
if the synchronization architecture allows it, it would be possible to
have Swarm models interact transparently with foreign simulation
objects. Imagine using Swarm in conjunction with your second favorite
simulation tool that may do a better job at describing special aspects
of your model. For example, the control algorithms for swarming
robotic vehicles could be modeled in Swarm, while their kinematics
could be modeled in a kinematic simulator such as RobCAD(tm). 

We propose a simple object-oriented architecture for running
distributed simulations with Swarm. The architecture is based on the
Adapter or Proxy pattern and the synchronization algorithm, called
Syncer. Syncer has been successfully applied to other simulation tools
in the past linking a Flexis control modeling tool with RobCAD and
Siman/Cinema, a discrete event simulator. Syncer is a low-overhead
method designed to maximize parallelism in the execution of the
distributed components while remaining transparent to the end
user. For Swarm we have re-implemented Syncer in Java and use Java RMI
or CORBA as the remote component communications framework.

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Implementing Multiple Model Swarms
Steve Jackson <address@hidden>
Jackson Scientific Computing

For a chinook salmon model, we implemented four different model swarms,
each with its own space and (in one case) time step. Each model
represented one life stage of the salmon. As a fish moves out of one
life stage, the fish object is dropped after its instance variables are
used to instantiate a new fish object in the next life stage model. An
alternative approach in which the fish objects are persistent and "know"
which model they belong to has been evaluated in a test code.


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