A numerical study of the two-dimensional steady free convection flow in an inclined annulus between two concentric square cavities filled with a porous medium is presented in this paper for the case when the side outer walls are kept with differentially heated temperature while the horizontal outer walls and the inner walls are insulated. The heated wall is assumed to have spatial sinusoidal temperature variation about a constant mean value. The Darcy model is used and the fluid is assumed to be a standard Boussinesq fluid. For the Cartesian coordinate system, the governing equations which were used in stream function form are discretized by using the finite difference method with successive under – relaxation method (SUR) and are solved by Gauss-Siedel iterative method. The upwind scheme was used for the transport terms in the energy conservation equation. The results are presented to demonstrate the streamlines, the isotherms, and the Nusselt number depending on the Rayleigh number ranging from (Ra =10 to 1000), dimension ratio from (Dr = 0.15 to 0.45), and the inclination angle from (= 0o to 45o). Also the effects of the amplitude (=0 to 1) and the wave number (f =0 to 5) of the heated side wall temperature variation on the free convection are investigated. The results show the effect of previous parameters (Ra, Dr,, , and f) on the flow fields and temperature profiles. It also show that the average Nusselt number is a strong function of the Rayleigh number, inclination angle, dimension ratio, and temperature variation. The peak value of the average Nusselt number based on the hot wall temperature is observed to occur at dimension ratio of (0.15), inclination angle of (40.1°), amplitude and wave number (1 & 0.75) for Rayleigh number of (1000).
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While practicing of International business particularly that centered on foreign direct investment, let on one side, to achieving objectives of transnational corporations specially that represented in continuous pursue to improving its cash flows and maximization of stockholders wealth which is considered the most important objective to the transnational corporations, but in the same time its lead, on other side, to increasing the foreign exchange risk exposuring these corporations. So, the transnational corporations (TNCs) struggling to make strategies which are dealing in smart way, with this risk and its management in way that enable to avoiding risk comple
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Ibn Khaldun is one of the best Arab Muslims scientists who participated in establishing Arabic Muslims heritage in all different disciplines & directions specially in sociology, neurological & his political theories which showed the development of Arabic philosophy in all scientific disciplines specially his introduction
Recent advancement in production technologist of manufacturing processes have left an important effects upon cost structure. Moreover the problem for providing necessary and adequate information for managerial decision making.
Therefore the cost – volume – profit analysis under the new activity based costing has replace the old method for Analysing the relation between C.V.P with respect to profit planning and control.
In brief the C.V.P object is to discuss the effect of changes on profit resulting from changes in sales volume, cost of manufacturing and selling price.
This study consists of four chapters:
The first chapter dea
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the boot of honesty in the dictionary the term linguistic and religious
heritage, literary and Islamic Sufi thought, and concept in the literature of Imam
Ali, peace is upon him. And studied the summary first concerns its presence in the
literature and implications and directions, either the second part, has cared for the
analytical study has found research that safe weight was the counterpart of the
personality of the Imam accompanied the character most prominent in his
character, namely, (courage), it has struggled to deliver a impact of humanity in his
time and after the word and deed, It was based on the imagination in the formation
of images sensual and intellectual, to his persuasion of the evidence and argu
In this work, we introduced the Jacobson radical (shortly Rad (Ș)) of the endomorphism semiring Ș = ( ), provided that is principal P.Q.- injective semimodule and some related concepts, we studied some properties and added conditions that we needed. The most prominent result is obtained in section three
-If is a principal self-generator semimodule, then (ȘȘ) = W(Ș).
Subject Classification: 16y60
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The present study aimed at examining the factors that affect the choice of A major among a sample of BA fe(male) students at the levels 3-8 in King Abdulaziz University (KAU), in Jeddah, Saudi Arabia. To meet this objective, a descriptive survey method was used together with a questionnaire that consisted of 4 axes to answer the central question: What are the factors affecting the choice of a major at the university? Results have shown that the item that measured the students’ ability to choose the major ranked (First); it was concerned with the effect on the students' choice of his/her major in the university. On the last position and with respect to this effect came the professional tendencies and desires. Results have also shown tha
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يعد التعلم النشطعملية نشطة ذهنية يبذٌل بها العقل الجهد الكافي لإِكتشاف المعرفة فالمعلمليس ناقلاً فيه للمعرفة ،) وانما مرشداً وموجهاً والمتعلم محور العملية التدريسية فيه،إِي عمليةإِبداع يختار منها المعلمما يستطيع الابداع فيه وتركيبه)حارص، 2015:6 والتعلم النشط طريقة تعاونية يشترك فيها جميع المتعلمين بالأنشطة والواجبات المتنوعة التي تسمح لهم بالأصغاء الإِيجابي والتحليل السليم للمادة والتفكي ا رلابداعي اذ تت
... Show MoreThis research has been devoted to the study narratines of the metaphysical concepts in Egypt during the Mamluk era ( 648-923 AD/1250-1517 AH). The study consists of three sections and an introductionwhich highlights the study at that time for its great impaction public life in Egypt.