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Identifying and Reducing Critical Lag in Finite Element Simulations
July 1996 (vol. 16 no. 4)
pp. 67-71
Interactive, immersive virtual environments allow observers to move freely about computer-generated 3D objects and to explore new environments. The effectiveness of these environments depends on the graphics used to model reality and the end-to-end lag time (that is, the delay between a user's action and the display of the result of that action). We focus on the latter issue, which has proved to be as important as frame rate for interactive displays. In particular, we analyze the components of lag time resulting from executing a finite element simulation on a multiprocessor system located in Argonne, Illinois, connected via ATM to an interactive visualization display located in San Diego, California. The primary application involves the analysis of a disk brake system that was demonstrated at the Supercomputing 1995 conference as part of the Information Wide Area Year (I-WAY) project, which entailed the interconnection of various supercomputing centers via a high-bandwidth, limited-access ATM network. The results of the study indicate that the critical component of lag is the simulation time. We discuss the use of network of supercomputers for reducing this time.

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Index Terms:
Immersive visualization, interactive virtual environments, critical lag components, end-to-end lag, simulation lag, VR over high-speed networks.
Valerie E. Taylor, Jian Chen, Milana Huang, Thomas Canfield, Rick Stevens, "Identifying and Reducing Critical Lag in Finite Element Simulations," IEEE Computer Graphics and Applications, vol. 16, no. 4, pp. 67-71, July 1996, doi:10.1109/38.511857
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