19,955 research outputs found
Enabling Cross-Event Optimization in Discrete-Event Simulation Through Compile-Time Event Batching
A discrete-event simulation (DES) involves the execution of a sequence of
event handlers dynamically scheduled at runtime. As a consequence, a priori
knowledge of the control flow of the overall simulation program is limited. In
particular, powerful optimizations supported by modern compilers can only be
applied on the scope of individual event handlers, which frequently involve
only a few lines of code. We propose a method that extends the scope for
compiler optimizations in discrete-event simulations by generating batches of
multiple events that are subjected to compiler optimizations as contiguous
procedures. A runtime mechanism executes suitable batches at negligible
overhead. Our method does not require any compiler extensions and introduces
only minor additional effort during model development. The feasibility and
potential performance gains of the approach are illustrated on the example of
an idealized proof-ofconcept model. We believe that the applicability of the
approach extends to general event-driven programs
Advanced flight control system study
The architecture, requirements, and system elements of an ultrareliable, advanced flight control system are described. The basic criteria are functional reliability of 10 to the minus 10 power/hour of flight and only 6 month scheduled maintenance. A distributed system architecture is described, including a multiplexed communication system, reliable bus controller, the use of skewed sensor arrays, and actuator interfaces. Test bed and flight evaluation program are proposed
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