The effect of seff-similar traffic on the delay of a single queue system is studied through the use of the measured traffic and models as input process. A model-driven simulation-based method is then proposed for the computation of mean line delay in a network design. Both the hybrid-FGN and the FARIMA algorithms have been used to synthesize self-similar sample paths. The comparison results with real-traffic data sets firmly establish the usefulness of the proposed model-driven simulation-based method. A practical database method is also introduced that helps the designer to determine the parameters in network design. This approach may play an important role in network design and analysis.

Recent extensive measurements of real-life traffic demonstrate that the probability density function of the traffic is noa-Gaussian. If a traffic model does not capture this characteristics, any analytical or simulation results will not be accurate. In this work, we study the impact of non-Gausslan traffic on network performance, and present an approach that can accurately model the marginal distribution of real-life traffic. Both the long- and short-range autocorrelations are also accounted. We show that the removal of non-Gaussian components of the process does not change its correlation structure, and we validate our promising procedure by simulations.

RSX-DAS is a flexible CAMAC-based data acquisition software system that runs on a variety of PDP-11 architectures and under RSX-11 operating systems. Since 1983, five versions of RSX-DAS have been developed at tile Plasma Physics Laboratory, University of California, Los Angeles, U.S.A. and the Institute of Plasma Physics, Academia Sinica, China. The system has modular, multi-tasking and concurrent processing features. The commnunication among seventeen tasks is accomplished through parent/offspring tasking, event flags and shared regions. The user interface to RSX-DAS consists of a set of user friendly commands, indirect command files and menus. The database consists of four static shared regions for the control of data acquisition and display, one dynamic shared region for the data of current shot, and data files for previous shots. The moduiarity of the CAMAC interface software allows operation on several CAMAC organizations, for example a parallel branch or some dedicated crates, and allows easy addition and subtraction of CAMAC hardware.

A new object-oriented Real Time System Simulator (RTSS) with the capability for simulation graphics and animation, has been developed and used for modeling the distributed data acquisition and processing systems at JET and AS]PP. Simulation allows estimates of response time, throughput and resource utilization for a variety of configurations to be investigated. Performance measurements, simulation and analysis are used together to calibrate and validate each other.

The HT-7U data system is being designed to support the HT-7U superconducting tokamak. For the HT-7U to achieve its mission of extremely long pulse and steady-state operation, the HT-7U data system must be flexible and robust. Corresponding to the various operation modes of the HT-7U experiment, a variety of system configurations and workload models are considered. A trace-driven simulation-based method and steady-state operational analysis technique is used for performance evaluation. These analyses show that much better performance may be obtained by applying the performance optimization techniques of fast switching networking, data compression, caching/buffering, pipelining, a real-time operating system, a real-time database, etc.