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browser, and visualized locally. The user can interact with the model by using
buttons on the HTML page.
Fig 2.6: Remote simulation and local visualization
Finally the paper introduces Skopeo, a Java-based, platform-independent 2DAnimation system.
Yiicessan, et al [30] introduces a Parallel Discrete Event Simulation (PDES) support
system to distribute simulation experiments over the Internet. There are several
approaches to exploiting parallelism in discrete event simulation; unfortunately each
of those has its own drawbacks. For example, a) in Dedicated Execution approach,
where dedicated functional units execute specific sequential simulation functions, the
speed tends to be limited as the management o f the future events list becomes the
bottleneck, b) in Hierarchical Decomposition, where a model is decomposed in a
hierarchical fashion such that an event consisting o f several sub-events to be
processed concurrently, is largely model dependent, c) in Parallel Replication, where
several replications o f a sequential simulation are executed independently on different
processor, each processor must contain enough memory to hold the entire model. The
paper describes a prototype o f a software architecture that would support PDES. The
main objective o f the proposed system is to plan parallel simulation experiments and
dynamically manages their execution. Via the Internet the system has access to a large
number o f sites (a PC or Workstation), from where it can dynamically selects one to
execute part (parallel replication) o f an experiment. The system uses OCBA [31] to
implement the experiment planner. The system has also data collection and analysis
capabilities to collect and analyse output data from each individual processor. Finally,
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