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).
يهدف البحث إلى تحقيق عدد من الأهداف: الكشف عن مدى تفاعلية الجمهور إزاء استخدام التطبيقات الإعلانية في الفضائيات عبر أجهزة الهاتف المحمول. التعرف على تفضيلات الجمهور بين التطبيقات. الوقوف على أهم الموضوعات التي يفضل الجمهور التفاعل معها في التطبيقات الإعلانية. الكشف عن أبرز المعوقات التي تواجه مستخدمي التطبيقات الإعلانية في الفضائيات عبر الهاتف المحمول. الوقوف على مدى مساهمة التطبيقات الإعلانية في الفضائي
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إن التغيرات السريعة والبعيدة المدى في تكنولوجيا المعلومات القائمة على أساس الالكترونيات الدقيقة تساعد في حدوث تحول في صورة الاقتصاد العالمي، وكذلك تساعد في تغيير المزايا التنافسية للبلدان، وربط المؤسسات البعيدة ببعضها البعض، ونشر الخدمات المالية على نطاق عالمي، وكذلك إثارة مشكلات جديدة او العكس فتح فرص جديدة أمام تنمية ونمو أفقر البلدان .
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The novel in its construction depends on set of life elements that is employed by the writer or the novelist to create a convincing world that resemble the real life world and as the novel is going toward experimentation and employing modern phenomenon we find the novelist tends to take advantage from the most realistic details to achieve the required convincing state through serious situations and the novelist Maysaloun Hadi depended in writing her novels on creating tight relations between the things and the elements that has inspired her which are mostly from the environment and from reality , as an example of these elements is the old inherited traditions that distinguish Iraq society as this element is a very important point in Iraq
... Show MoreLong memory analysis is one of the most active areas in econometrics and time series where various methods have been introduced to identify and estimate the long memory parameter in partially integrated time series. One of the most common models used to represent time series that have a long memory is the ARFIMA (Auto Regressive Fractional Integration Moving Average Model) which diffs are a fractional number called the fractional parameter. To analyze and determine the ARFIMA model, the fractal parameter must be estimated. There are many methods for fractional parameter estimation. In this research, the estimation methods were divided into indirect methods, where the Hurst parameter is estimated fir
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Cette recherche étudie les structures composant Barbara, un poème de Jacques Prévert pour mettre en valeur la particularité de ce langage. Nous avons d'abord, dissocié ces structures, en : structure thématique, actancielle, syntaxico-énonciative, sémantique, formelle et finalement spacio-temporelle en vue de les analyser minutieusement. Le poète a adopté pour les thèmes : souvenir, nostalgie et guerre, un langage simple et une syntaxe incomplexe. L'usage du lexique et des figures de style célèbrent ces thèmes. La forme, la versification et la sonorité approfondissent ces images et renforcent ce langage. Ce poème dépend des phrases simples et variées : affirmative, interrogative, exclamative qui s'orientent vers des acte
... Show MoreQuran orders and commandments and principles, has avenged children, their status and dearest, and saved their lives, which reached ill before Islam, and filled the hearts of the fathers and mothers for their love, but to make them embellish life.
عرض رسائل (الموقف من التعددية الحزبية في الفكر السياسي الاسلامي المعاصر)
اثر بديع الزمان سعيد النورسي على الفكر الاسلامي المعاصر في تركيا