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Benghazi, Libya

University of Benghazi , formerly known as the Garyounis University, is a public university in Benghazi, Libya.and it is one of the most important institutes of higher education in Libya.It is located in Benghazi the second largest city in the country. It was founded on 1955 as the University of Libya. Wikipedia.

Elhaffar A.,University of Benghazi
Proceedings of the Mediterranean Electrotechnical Conference - MELECON | Year: 2012

Traveling Waves Recorders (TWR) are used to accurately detect the arrival times of the traveling waves (TWs) initiated due to faults in the power system. A concept of fault-location observability and a multi-end fault-location scheme for transmission networks based on TWRs are presented. The fault location is calculated at a computer center using the minimum number of TWRs. Few TWRs are installed in the existing power transmission networks so that the fault can be located correctly and economically in the network. A minimum TWR placement is proposed to the existing transmission network. The discrete wavelet transform (DWT) is used to find the high frequency contents of the TWR signals. The double-end method is utilized using the shortest path from nearest TWRs to the faulted line. Validation of fault location is examined by ATP/EMTP simulations for a typical 400 kV power system. © 2012 IEEE. Source

Abboud J.H.,University of Benghazi
Materials and Design | Year: 2012

The surface of nodular cast iron has been melted and rapidly solidified by Tungsten Inert Gas (TIG) process to produce a chilled structure of high hardness and better erosion resistance. Welding currents of magnitude 100, 150, and 200. A at a constant voltage of 72 have been used to melt the surface of nodular cast iron. Microstructural characterization, hardness measurements, and erosion wear tests have been performed on these modified surfaces as well as on the untreated material. Microstructural characterization has shown that surface melting resulted in complete or partial dissolution of the graphite nodules and resolidification of primary austenite dendrites, which undergo further decomposition into ferrite and cementite, and interdendritic of acicular eutectic; their microhardness measured across the melted depth ranged between 600 and 800. Hv. The scale of the dendrites and the interdendritic eutectic became coarser when a higher current is used. The results also indicated that remelting process by TIG improved erosion resistance by three to four times. Eroded surface observations of the as-received and TIG melted samples showed a ductile behavior with a maximum erosion rate at 30°. The fine microstructures obtained by the rapid cooling and the formation of a large amount of eutectic cementite instead of the graphite have contributed greatly to the plastic flow and consequently to the better erosion resistance of the TIG surface melted samples. © 2011. Source

Abboud J.H.,University of Benghazi
Surface and Coatings Technology | Year: 2013

Experimental investigations based on Response Surface Method (RSM) were carried out to study the influence of laser power, nitrogen flow rate, and scanning speed on the microstructure, depth, hardness, and cracking of a set of titanium nitrided surface layers produced by laser gas nitriding. Laser powers ranged between 1 and 5kW, scanning speeds 5 to 20mm/min, and nitrogen gas flow rate ranged from 500 to 4000l/min. The aim was to use RSM in the design of experiment to find suitable processing parameters which produce deep and crack free nitrided layers with a high surface hardness. Optical microscope, scanning electron microscope equipped with energy dispersive spectroscopy (EDS) analysis, and X-ray diffraction were used to characterize the microstructure and composition of the nitrided layers. Microhardness at a distance of 0.15mm from the surface for all tracks was measured. The results showed that laser melting of titanium surface in a nitrogen containing atmosphere has led to the formation of a nitrided layer characterized with a strong convective flow and of a dense structure of TiN dendrites heterogeneously distributed. The TiN dendrites, which formed either directly from the melt or as a result of the peritectic reaction L+αTi→TiN, were of various sizes and shapes and distributed non uniformly. The volume fraction of TiN dendrites in the melted zone is a function of processing speed and power being higher at slower speed and high power. The convectional flow not only affects the surface quality but also leads to effective nitrogen transport to a deeper region. The formation of TiN significantly increases the microhardness of the surface but it makes the surface rough. The optimum process parameter settings which were determined statistically in terms of power, scanning speed and nitrogen gas flow rate were found to be 2.8kW laser power, 5mm/s scanning speed and 2000l/h nitrogen flow rate which would result in a maximum microhardness of approximately 1900HV0.15. © 2012 Elsevier B.V. Source

Ahmida M.H.S.,University of Benghazi
Experimental and Toxicologic Pathology | Year: 2012

Vancomycin (VAN) is a glycopeptide antibiotic which is active against gram positive bacteria including methicillin resistant Staphylococci. Free radicals are involved in the pathogenesis of vancomycin-induced nephrotoxicity. Therefore, the present study was conducted to investigate the antioxidant potential of curcumin (CUR) against the nephrotoxicity of vancomycin in male rats. Animals used in this study were divided into four groups; the first group was used as control, the second, third and fourth groups were treated orally with curcumin (200. mg/kg. BW/day), vancomycin (200. mg/kg. BW/day, i.p.), vancomycin plus curcumin, respectively. Curcumin was administered 2 weeks before and 1 week simultaneously with vancomycin. Results showed that thiobarbituric acid reactive substances (TBARS) in plasma and kidney tissue were significantly increased after vancomycin administration. While, the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in plasma and kidney tissue and the content of glutathione (GSH) in kidney tissue were decreased compared to control. Vancomycin significantly increased the levels of urea and creatinine. The presence of curcumin with vancomycin caused reduction in induction levels of TBARS in plasma and kidney, urea and creatinine. It ameliorated vancomycin-induced decrease in the activities of antioxidant enzymes and GSH. The presence of curcumin with vancomycin alleviated its nephrotoxic effects. It can be concluded that curcumin has beneficial influences and could be able to antagonize vancomycin nephrotoxicity. © 2010 Elsevier GmbH. Source

Altaboli A.,University of Benghazi
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

The purpose of this study is to compare the effects of the two font styles (serif and sans-serif) on the users' perception of visual aesthetics of website interface design. Two font types were tests in this study, namely: "Time News Roman" representing the "serif" style and "Calibri" representing the "sans-serif" style. They were chosen because they are two of the widely used font types on the web and because they are the default font types of many of the most popular word processing and web developing software. Analysis of results showed that font type has a statistically significant effect on perceived visual aesthetics. The designs with the Time New Roman font was perceived as having better visual aesthetics. However, this effect was only significant on the overall perception of visual aesthetics; it wasn't significant in each of the four facets of visual aesthetics tested in this study. © 2013 Springer-Verlag. Source

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