This paper investigate a sensorless speed control of a separately excited dc motor fed from a buck type dc-dc converter. The control system is designed in digital technique by using a two dimension look-up table. The performance of the drive system was evaluated by digital simulation using Simulink toolbox of Matlab.
The present study aims to explore the effectiveness of a proposed study unit based on the funds of knowledge theory in developing the attitudes towards cultural identity and the proposed study unit. In order to achieve the goal of the study, the two researchers followed the quasi-experimental approach, where the study sample consisted of (28) female students of the fifth-grade at Al-Jeelah Basic Education School, Al-Dakhiliyah Governorate in the Sultanate of Oman. The data were collected by two scales: the first is a scale of attitudes towards cultural identity consisting of (26) items. The second was a scale of attitudes towards the proposed study unit, which consisted of (24) items. The results of the study revealed that the effect of
... Show MoreThe corrosion behavior of low carbon steel in washing water of crude oil solution has been studied potentiostatically at five temperatures in the range (30–70)°C .The corrosion potential shifted to more negative values with increasing temperature and the corrosion current density increased with increasing temperature. Folic acid had on inhibiting effect on the corrosion of low carbon steel in washing water at a concentration (5× 10-4-- 5× 10-3 ) mol/dm3 over the temperature range (30–70)°C. Values of the protection efficiency were calculated from the corrosion current density .From the general results for this study, it can be seen that thermodynamic and kinetic function were also calculated (?G, ?S, ?H and Ea )
... Show MoreIt was recorded that Terpinen-4-ol has an anti-parasitic properties, so it will be noteworthy to intensify the studies about this compound.
This study aims to test the effectiveness of terpinen-4-ol on amastigote forms of Leishmania parasite in macrophages.
This effect was studied by adding increasing concentrations of Terpinen-4-ol to culture wells containing mouse macrophages that were previously incubated with the promastigote forms of the parasites for 24 hours .Then, they were incubated for another 24 hours with increasing concentrations of Terpinen-4-ol. After, Parasites were enumerated into macrophages in wells either treated with Terpinen-4-ol or in control wells.
Treatment with Ter
... Show MoreAt the beginning of the nineties increased responsibility of the auditor to the community as the demand for auditing the environmental performance for the economic units in addition to audit the financial performance. With the aim of preserving the environment and reducing the damagse as aresult of the negative effects of the activities of these units.
The researh deal with two sides the first one identifies the theoretical framework of the concept of environmental audits, requirements, methods, types of procedures, and duties of the auditor in conducting environmental audits. It also deals with the concept of the enviro
... Show MoreAlPO4 catalysts supported with WO3 were prepared by impregnating the catalysts with ammonium metatungstate. The catalysts were checked by X-ray Diffraction (XRD), AFM, and SEM; also, the catalysts analysis was done by X-Ray (EDX). Finally, the N2 adsorption-desorption was used to measure the pore volume and surface area of the catalyst. The prepared catalyst has a surface area of 185.83 m2/g, pore volume of 0.645 cm3/g at a calcination temperature of 500°C for 3 hrs, and particle size of AlPO4 with an average of 35.36 nm. Transesterification of edible oil using WO3/AlPO4 was performed, it was observed that WO3/AlPO4 catalysts give high conversion of edible oil, and this is attributed to the high surface area, smaller particle size, and the
... Show MoreThe research in the linguistic structures of the historians Al-Yaqoubi is considered a model of the important topics in historical studies in general, given its importance in the lives of peoples due to its connotations and meanings that summarize interpretation, clarification, and prolonged speech, as it includes life meanings with many dimensions, these structures have been used in historical incidents Important, and throughout the different ages, as it can be used to support an opinion, solve problems, prove evidence, increase wisdom, and it needs rich life experiences, and a sound language, to use it, and needs a wide absorptive capacity for the recipient, the research included linguistic structures in the achievement of science , Lingu
... Show MoreA simple and accurate method to determinate furosemide (FUR) based on converting the secondary amine to primary amine with acidic hydrolysis then azotization by nitrous acid and coupled with resorcinol as a coupling agent in aqueous medium at pH 13. The optical characteristic like beers law limit found to be (0.25-2.5) μg.ml−1, detection and quantification limits (0.0196) (0.0654) μg.ml−1respectivly and Sandel sensitivity was 0.006738 μg.cm−2. The least-square method was used to evaluate the regression equation and the correlation coefficient. The resulted azo dye has a maximum absorbance at 430 nm with light oran
This study aims at describing the identity crisis of Diaspora people (Arab -American) in "Laila Halaby's" novel "Once in A promise Land". Halaby tackles the issues of racism, exclusion, and instability of identity that affect the Arab American community after the terrorist event of eleventh of September. She sheds light on the experiences of her significant characters Salwa and Jassim in America, clarifying how this event weakened their social position and turns their presence in America questionable. "Halaby" describes the bitterness of her characters who are induced into a dream of belonging to a land that transcends their original culture and religious values as well as their language. "Halaby" explains the subsistence in America involvi
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