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The present work investigates the influence of magnetic field on the friction coefficient displayed by sliding of steel pin on aluminium, steel and polyamide discs lubricated by paraffin oil and dispersed by different lubricant additives such as zinc dialkyldithiophosphates (ZDDP), molybdenum disulphide (MoS2), heteropolar organic based additive (CMOC), graphite (C), detergent additive (calcium sulphonate) (DA), polytetrafluroethylene (PTFE) and polymethyl methacrylate (PMMA). The experiments showed that, aluminium as a paramagnetic material recorded higher values of friction coefficient than steel and polyamide. That observation confirms that in spite of the increase of the attractive force generated from the magnetic field for steel/steel and the electrostatic charge for polyamide/steel, oil molecules were more adhered into the surfaces of steel and polyamide than aluminium and consequently friction coefficient significantly decreased. When the oil was dispersed by additives, it was found that, friction coefficient slightly increased with increasing magnetic field for oil dispersed by ZDDP additive. For oil dispersed by MoS2 friction coefficient displayed by aluminium disc showed relatively lower values in the presence of the magnetic field than that displayed by polyamide and steel discs. Magnetic field drastically decreased friction coefficient displayed by aluminium and steel disc. As for polyamide disc friction coefficient slightly increased with increasing the magnetic field. Aluminium disc displayed the lowest friction coefficient in the presence of C, which decreased with increasing magnetic field. For steel disc friction coefficient displayed the highest values. Polyamide disc showed no change in friction values as the intensity of the magnetic field increased. For oil dispersed by DA, steel disc showed significant friction decrease. Aluminium disc showed slight friction increase with increasing magnetic field, while polyamide disc showed slight friction decrease. PTFE particles dispersed in the oil were much influenced by the magnetic field, where the friction coefficient displayed by steel drastically decreased with increasing magnetic field. Aluminium and polyamide discs showed an increasing trend as the magnetic field increased. As for PMMA particles dispersed in oil aluminium disc showed slight friction increase, while steel and polyamide discs gave decreasing trend of friction as the magnetic field increased.

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This paper highlights the basic concepts and advantages of More/All Electric Aircraft （MEA/AEA) in the area of aircraft industry. MEA is anticipated to optimize the aircraft performance, reduce the total cost and increase safety, reliability and robustness. The Combined Starter/Generator （CS/G） system is advised as a key technology to enable MEA/AEA. A detailed analysis for the performance requirements of CS/G system is carried out. A comparative study for different machine candidates for CS/G is proposed, while focusing on Fault-tolerance, reliability and robustness.

This paper highlights the basic concepts and advantages of More/All Electric Aircraft （MEA/AEA) in the area of aircraft industry. MEA is anticipated to optimize the aircraft performance, reduce the total cost and increase safety, reliability and robustness. The Combined Starter/Generator （CS/G） system is advised as a key technology to enable MEA/AEA. A detailed analysis for the performance requirements of CS/G system is carried out. A comparative study for different machine candidates for CS/G is proposed, while focusing on Fault-tolerance, reliability and robustness.

The main purpose of this research is to allow doubly fed induction generator (DFIG) to participate effectively in interconnected power systems load frequency control via improved harmony algorithm (IHA). In order to tune the parameters of the PI controllers without considering the complexity associated with the modeling of the power system, the corresponding optimization problem is formulated in terms of an objective function, which represents the norm of the closed-loop area control error signal. A three-area interconnected power system subjected to major disturbances is investigated to verify the effectiveness of the developed algorithm of DFIG wind turbine participation in load frequency regulation. Time domain simulation results are presented to prove the improved performance of the developed IHA-based controller compared with genetic algorithm, simulated annealing, and a conventional integral controller. The results show that the developed IHA controller has better behavior over other algorithms in terms of settling times and other indices