Fully superconducting generator (FSG) is one of the promising applications of superconductors in electric power sector. Meanwhile, transient stability of FSG is an important issue in developing this new machine. An approach is suggested in this paper for the design of a fuzzy logic governor controller (FLC) as a possible mean to improve the FSG stability under transient conditions.In this approach, unsymmetrical non-linear membership functions are used, whilethenumber ofFLC parameters to be properly designed is 15 parameters, including scaling factors for input and output variables along with widths and centers of fuzzy sets of input variables. A genetic algorithm is used to optimally choose all these parameters. Simulation results show that the proposed FLC leads to a significant improvement in the transient stability and performance of a FSG connected to an infinite-bus.

Proportional-plus-Integral-plus-Derivative (PID) controllers are widely used in the industrial world. Due to their popularity, a large number of methods have been suggested in the literature to tune them. This paper summarizes and compares seven different PID tuning techniques (in addition to some of their variations). The comparison includes some of the earlyapproaches; namely, Ziegler-Nichols methods, minimum error, phase and gain margins, pole allocation, and LQR. Modern techniques (fuzzy logic and genetic algorithm) are also used and assessed. The seven tuning alternatives are evaluated in terms of their performance, complexity and flexibility.

The objective ofthis research is to obtain a relationship between Nusselt and Reynolds numbers of fluid flow in packed bed containing spheres of different sizes. Also, to develop a universal relationship for the Nusselt number in a wide range of Reynolds number and compare the results with those of empty tube. The experimental work covered a range of Reynolds numbers, based on tube diameter, from 2167 to 19400 at various spherical P.V.C.porous media particle diameters from 0.003 to 0.012 m as well as without porous media(empty section). The results of this experimental work show that the Nusselt number improves by a factor of 3.8 to 6.3 times when using porous media for sphere diameters ranging from 0.012 to 0.003 m respectively as compared to the empty tube. Small size spherical porous media yield much better results than large sizes because they offer more turbulence and eddy, while higher pressure drop develops. These results improve the heat transfer coefficient.

We describe the steps and the main features of the modern syllogistic method, which is a very powerful technique of deductive inference.This method ferrets out from a set of premises all that can be concluded from it, with the resulting conclusions cast in the simplest or most compact form. We demonstrate the applicability of the method in a variety of engineering problems via five examples that illustrate its mathematical details and exhibit the nature of conclusions it can come up with.The method is shown to be particularly useful for detecting inconsistency within a set of given premises or hypotheses and it helps the engineer confront fallacy-based argumentation.The method is also demonstrated to yield fruitful results when combined with the safety technique known as fault-tree analysis.It is also used in selective deduction and in informed decision making.