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Flexray is a high speed communication protocol designed for distributive control in automotive control applications. Control performance not only depends on the control algorithm but also on the scheduling constraints in communication. A balance between the control performance and communication constraints must required for the choice of the sampling rates of the control loops in a node. In this paper, an optimum sampling period of control loops to minimize the cost function, satisfying the scheduling constraints is obtained. An algorithm to obtain the delay in service of each task in a node of the control loop in the hyper period has been also developed. (C) 2015 The Authors. Published by Elsevier B.V.

In this article, we present an exact theoretical analysis of an system, with arbitrary distribution of relative deadline for the end of service, operated under the first come first served scheduling policy with exact admission control. We provide an explicit solution to the functional equation that must be satisfied by the workload distribution, when the system reaches steady state. We use this solution to derive explicit expressions for the loss ratio and the sojourn time distribution. Finally, we compare this loss ratio with that of a similar system operating without admission control, in the cases of some common distributions of the relative deadline.

It is becoming increasingly important for power system planning and operating engineers to be capable of performing comprehensive voltage stability analyses of the systems. This need is largely due to recent trends towards operating systems under stressed conditions as a result of increasing system loads without sufficient transmission and/or generation enhancements. This paper discusses effect of the on-load tap changing transformers (OLTCs) on voltage stability and identifying critical OLTCs to avoid possibilities of voltage instability conditions. The developed approach has been tested on sample systems. Results obtained on an equivalent system of 24-node practical power system are presented.

In this paper, we develop a tool for carrying out acceptance tests in a multiprocessor system, for workloads that include both sporadic hard tasks with specified resource requirements, and multimedia tasks with firm (m, k) guarantees. The tool is a two-level scheduler. The higher-level server planner generates server arrangements for the multimedia server, such that it can meet the (m, k) firm guarantees, and can execute optional task instances as well, while the lower-level feasibility checker determines the schedulability of the sporadic tasks under the specified server arrangement. The two levels iterate until schedulability is determined. The tool has been validated through simulation studies.