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The evaluation of the minimum distance of linear block codes remains an open problem in coding theory, and it is not easy to determine its true value by classical methods, for this reason the problem has been solved in the literature with heuristic techniques such as genetic algorithms and local search algorithms. In this paper we propose two approaches to attack the hardness of this problem. The first approach is based on genetic algorithms and it yield to good results comparing to another work based also on genetic algorithms. The second approach is based on a new randomized algorithm which we call "Multiple Impulse Method (MIM)", where the principle is to search codewords locally around the all-zero codeword perturbed by a minimum level of noise, anticipating that the resultant nearest nonzero codewords will most likely contain the minimum Hamming-weight codeword whose Hamming weight is equal to the minimum distance of the linear code

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Partial upgrading is an emerging direction in the processing of Canadian oil sands bitumen in response to the economic and environmental challenges in the oil sands industry. Partial upgrading aims to improve bitumen quality only to the level at which pipeline specifications are met without use of diluent. Given that partial upgrading technologies have not yet reached commercial deployment, there is a lack of technical data to assess the expected benefits in terms of energy input and greenhouse gas emissions reduction. In this study, we present an assessment of a partial upgrading scheme using detailed process simulation. We developed a conceptual process scheme considering visbreaking, solvent deasphalting, and naphtha hydrotreating as the core partial upgrading processes. Reactor models were assembled using experimental data from CanmetENERGY's pilot plant facilities and from the literature and integrated into a plant-wide simulation model. Simulations allowed the examination of trends in partial upgrader product yields and quality and enabled a comparison with traditional bitumen upgrading.

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This paper focuses on the problem of controlling a single phase DC-AC switched power converter used in Uninterruptible Power Supply (UPS). The control objective is to generate, at the system output, a sinusoidal voltage with amplitude and frequency fixed by the reference signal. To this end, three types of regulators are designed based on Backstepping technique, Sliding Mode approach and linear PID controller. A comparative study of performances of designed controllers is made by simulations in Matlab/Simulink environment.