Summary This article presents a method to consider the probabilistic nature of load impedance and harmonic currents by designing a multi‐step inductive‐capacitive (LC) compensator consisting of switchable units thus assuming that a single unit is not sufficient to ensure satisfactory results. The proposed algorithm divides the time period into sub‐regions according to the scheduled number of switchable units over which the multi‐step LC compensator is optimized through different performance criteria; maximizing the power factor (PF), minimizing the transmission loss (TL) or minimizing the voltage total harmonic distortion (VTHD); as objective function resulting in lower variance, and hence, the more accurate expectation is obtained. Genetic algorithm (GA) is used to estimate that steps while holding the performance quantities at the corresponding desired values and constraining the compensator values which would create resonance. Also, the manufacturer's standard values for power shunt capacitors with/without equal steps are considered. GA is a search mechanism based on the principle of natural selection and population genetics. The contribution of the proposed procedure is demonstrated in examples taken from previous publications. Finally, simulated results show that the multi‐step LC compensator provides a considerable improvement in the performance in case of the probabilistic condition. Copyright © 2016 John Wiley & Sons, Ltd.

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Multiprocessor task scheduling problem is a pressing problem that affects systems' performance and is still being investigated by the researchers. Finding the optimal schedules is considered to be a computationally hard problem. Recently, researchers have used fuzzy logic in the field of task scheduling to achieve optimal performance, but this area of research is still not well investigated. In addition, there are various scheduling algorithms that used fuzzy logic but most of them are often performed on uniprocessor systems. This article presents a new proposed algorithm in which the priorities of the tasks are derived from the fuzzy logic and bottom level parameter. This approach is designed to find task schedules with optimal or sub-optimal lengths in order to achieve high performance for a multiprocessor environment. With respect to the proposed algorithm, the precedence constraints between the non-preemptive tasks and their execution times are known and described by a directed acyclic graph. The number of processors is fixed, the communication costs are negligible and the processors are homogeneous. The suggested technique is tested and compared with the Prototype Standard Task Graph Set. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.