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ABSTRACT In this paper, modeling, simulation and performance analysis of the three phase permanent magnet brushless direct current (PMBLDC) motor using Fuzzy Logic Controller (FLC), Genetic Algorithm controller (FGAC), hybrid Neuro-Genetic Algorithm Controller (NGAC), Hybrid -Fuzzy controller (NFC) and Hybrid Neuro-Fuzzy controller (NFC) based on Genetic Algorithm (GA) under the effect of external load for improving the transient and steady state response is presented. The applications of the three phase permanent magnet brushless direct current (PMBLDC) motor are increasing day by day. In order to have proper utilization of these motors and to control them effectively it is important to have proper mathematical modeling of these motors. Similarly effective control these motors are also essential to have successful application of the devices across multiple domains. This paper handles both these important aspects. A m been derived to represent a three phase permanent magnet brushless direct current (PMBLDC) motor model, its utility can be noted from the fact that different motors can be analyzed easily using the proposed model. The mathematical model was subjected to open loop and closed loop analysis to study the stability and performance. In this paper in order to validate the approach a MATLAB/SIMULINK model having intelligent controllers are constructed to control the modeled three phase permanent magnet brushless direct current (PMBLDC) motor under the effect of external disturbances for enhancement of static & dynamic response. 

Keywords Permanent Magnet Brushless Direct Current (PMBLDC) motor, Fuzzy Logic Controller (FLC), Genetic Algorithm (GA), Hybrid Neuro-Fuzzy controller (NFC) based on Genetic Algorithm GA, MATLAB/Simulink etc.

Abstract

This study aims to discover the problems that face Libyan university

students when translating Libyan proverbs into English. It also focuses on

the techniques applied by the students in the translation process. To

achieve the goals, the researchers asked the study participants to

translate about ten Libyan proverbs into Arabic. The sample of this study

consisted of twelve second year students specialized in translation from

the English department in the Assabha Faculty of Arts. The results

showed that some students faced problems in transferring the meaning of

Libyan proverbs into the target language (English). This could be

attributed to the different culture between both languages (i.e. Arabic and

English) The results also revealed that the participants used literal

translation method as their primary strategy. Translation tutors and

curriculum designers need to focus on the effective strategies to achieve

the correct translation of Libyan proverbs into English

In this paper we present an approach to optimistic concurrency control where the write phase occurs before the validation phase (RWV instead of RVW). Our work extends earlier research into real-time databases that utilized virtual execution to lower disk access overheads. Such work demonstrated that virtual execution allowed an increase in transactions completing before deadlines expired and improvements in overall throughput. However, we demonstrate that only with the reversal of the write and validation phases can virtual execution reach its full potential.

Abstract: The igneous rock unit of Al-Haruj Al-Aswad were interpreted using satellite image. The satellite image of Land sat bands from one tosevenhas captured by the Thematic Mapper (TM7) scanner. These imageswere processed and interpreted with following standard technique. Karhunen– Loèvetransform were employed to produce principalcomponent images. Then, they were paintedby using RGB color system to produce false color images from principal component images and ratio images. The resulted images were interpreted in the matter of geology of the area.Theprincipalcomponent transformation is helpful in mapping different lava flow phases in the area. This transform have used the correlation between the corresponding pixels in images of different bands. Six lava flow phases was interpreted depends on their color and shade in the processed satellite images. 

Due to an account of its excellent hardness and wear behavior, AISI D2 is used widely in producing of blanking and cold-forming dies, Punches, Shafts, Studs, and Bolts. Increasing toughness at a fixed high level of hardness is growing requirement for this kind of applications. Improving microstructure characteristics, especially carbides distribution by specific heat treatment, is an appropriate way to meet such requirement. The effect of quenching media on microstructure and hardness of pre-heated and austentized (at 980oC) AISI-D2 tool steel has been studied, and hardness and carbides morphology have been investigated. Three different medias, water, oil and water/oil (time quenching) have been used, then all samples were followed by the same tempering 350oC/1 hour. It has been found that the optimal carbides distribution and optimum hardness have been resulted from a time quenching method.