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Synchronous Parallel System for Emulation and Discrete Event SimulationA synchronous parallel system for emulation and discrete event simulation having parallel nodes responds to received messages at each node by generating event objects having individual time stamps, stores only the changes to the state variables of the simulation object attributable to the event object and produces corresponding messages. The system refrains from transmitting the messages and changing the state variables while it determines whether the changes are superseded, and then stores the unchanged state variables in the event object for later restoral to the simulation object if called for. This determination preferably includes sensing the time stamp of each new event object and determining which new event object has the earliest time stamp as the local event horizon, determining the earliest local event horizon of the nodes as the global event horizon, and ignoring events whose time stamps are less than the global event horizon. Host processing between the system and external terminals enables such a terminal to query, monitor, command or participate with a simulation object during the simulation process.
Document ID
20020034986
Document Type
Other - Patent
Authors
Steinman, Jeffrey S. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Date Acquired
August 20, 2013
Publication Date
November 27, 2001
Subject Category
Computer Systems
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-6,324,495|NASA-Case-NPO-18414-4
Patent Application
US-Patent-Appl-SN-094386|US-Patent-Appl-SN-246372|US-Patent-Appl-SN-880211
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