University of Bahrain

About: University of Bahrain is a education organization based out in Madīnat ‘Īsá, Bahrain. It is known for research contribution in the topics: Thin film & Doping. The organization has 1650 authors who have published 3405 publications receiving 48162 citations. The organization is also known as: Bahrain University & UoB.

DSP-based implementation of fast terminal synergetic control for a DC–DC Buck converter

Abstract: Finite time convergence based on robust synergetic control (SC) theory and terminal attractor techniques is investigated. To this end a fast terminal synergetic control law (FTSC) is applied to drive a DC–DC Buck converter via simulation and through a dSpace based experimental setup to validate the approach. As robust as sliding mode control, the synergetic approach used is chattering free and provides rapid convergence. Efficacy of the proposed fast terminal synergetic controller is tested for step load change and output voltage variation and results compared to classical synergetic and PI control. Experimental validation using dSpace DS1104 confirms the results obtained in simulation showing the soundness of this approach compared to synergetic and PI controllers.

Block predictor-corrector schemes for the parallel solution of ODEs

Abstract: A fourth-order block method based on the composite Simpson rule is developed for the parallel solution of ordinary differential equations. Like the block scheme based on the composite Trapezoidal Rule, its principal error term is linear in the block size while the increased order and stability allow a modest increase in parallelism without further computational complexity. Numerical results confirm the enhanced properties of the higher-order method.

Revealing a room temperature ferromagnetism in cadmium oxide nanoparticles: an experimental and first-principles study

Abstract: We obtain a single cadmium oxide phase from powder synthesized by a thermal decomposition method of cadmium acetate dehydrate. The yielded powder is annealed in air, vacuum, and H2 gas in order to create point defects. Magnetization-field curves reveal the appearance of diamagnetic behavior with a ferromagnetic component for all the powders. Powder annealing under vacuum and H2 atmosphere leads to a saturation magnetization 1.15 memu g−1 and 1.2 memu g−1 respectively with an increase by 45% and 16% compared to the one annealed in air. We show that annealing in vacuum produces mainly oxygen vacancies while annealing in H2 gas creates mainly Cd vacancy leading to room temperature ferromagnetic (RTFM) component together with known diamagnetic properties. Ab initio calculations performed on the CdO nanoparticles show that the magnetism is governed by polarized hybrid states of the Cd d and O p orbitals together with the vacancy.