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).
تحيا الأمم بتراثها فهو الأساس الذي تنطلق منهُ، وما من أمة إلاّ ولها تراث، وهو سر حياتها وديمومتها ، فالأمة العربية الأسلامية لها تراث تليد التي تشرفت بحمل أقدس رسالة سماوية وأكملها لأمم الأرض، فكانت نبراساً أهتدت به البشرية حتى انتشلتها من واقعها المريض إلى أرغد عيش وأقوم خلق وأنبل نفس .
The study aimed to identify the E-leadership practice at Princess Nora Bint Abdul Rahman University and to explore the obstacles that are facing the leaders in the implementation of E-leadership, in addition to find mechanisms to improve the practice of electronic driving at the university in light of the Corona pandemic. A descriptive analytical approach was used by depending on a questionnaire to collect the needed data. The study sample consisted of (139) heads of departments, attorneys' colleges and support Deanships universities. The study results showed that E-leadership employment recorded a medium to high degree. Especially at university, that publishing decisions electronically and uses technical means in providing its services.
... Show Moreملخص الدراسة
سعت الدراسة تعرف اثراستعمال الأنموذج المعملي في تصحيح المفاهيم الرياضية شائعة الخطأ لدى طلاب الصف الأول المتوسط بالإجابة عن السؤال "ما اثر استعمال الأنموذج المعملي في تصحيح المفاهيم الرياضية شائعة الخطأ لدى طلاب الصف الأول المتوسط" ولتحقيق هدف الدراسة وضعت الفرضية الصفرية "لايوجد فرق ذو دلالة إحصائية عند مستوى الدلالة (0.05) بين متوسطي درجات طلاب المجموعة التجريبية الذين يدرسون المادة المقرر
The idea of the research at first was to find out about the rare occurrence, which is the occurrence of a violation in the same madhhab and between two Shafi’i scholars such as Al-Amadi and Ibn Al-Subki. The scholarly had some brief and then moved on to the fundamentalist violations that occurred between them in the syllabus of the hearing within the chapter on analogy exclusively. The diffuse division (within the sounding and division) of the observer and the debates, or is it confined to the beholder without the debates, Imam Al-Amadi sees the inadmissibility of analogy with the reasons, while Imam Ibn Al-Subki argues that it is permissible, and Imam Al-Amdi sees that the widespread division is an argument for the observer (Muj
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This research aims to investigate the impact of a training program for teachers of chemistry according to the strategies for both sides of the brain together in academic achievement for their students, the sample consisted of a 12 teachers of both genders who are teaching chemistry for the students of the fifth scientific secondary schools of the General Directorate for the Education in Garmiyan/Sulaymaniyah governorate, Iraqi Kurdistan region, where five teachers of them randomly selected to involve the training program, and seven teachers did not participate in the proposed training program, where a sample of students was selected for each group of teachers about 147 male and female students for teachers of the experiment
... Show MoreÖzet
Sözlü Türk halk edebiyatı ürünleri içinde önemli yere sahip olan türlerden biri de atasözleridir. Atasözleri, nesilden nesile halk ağzında dolaĢan, kimin söylediği bilinmeyen, birtakım gerçekleri kısa ve öz bir Ģekilde ifade eden sözlerdir. Türk atasözleri Orhun Abideleri‟nde ilk kez karĢımıza çıkmakla birlikte, Uygur dönemi yazıtlarında ve özellikle Dîvânü Lûgati‟t Türk‟te geniĢ yer bulmuĢtur. Dilin anlatım ve kullanım imkânlarını geliĢtiren atasözlerine, dünyanın bütün dillerinde rastlanabilir. Bunun için, söyleyiĢte güzel, anlatımda güçlü, kavramda önemli unsurlar içeren kalıplaĢmıĢ sözler halinde bulunurlar. Bu çalıĢmada, Türk halk edebiyatında atas
يهدف البحث الحالي إلى معرفة اثر التدريس بطريقة التنقيب الحواري في حفظ النصوص الأدبية لدى طلبة قسم اللغة الكردية، اختارت الباحثة طلبة المرحلة الثانية في قسم اللغة الكردية بكلية التربية ابن رشد، للعام الدراسي
(2008-2009) ميدان لتطبيق تجربتها.
تألفت عينة الدراسة من (48) طالبا وطالبة، تم توزيعها عشوائيا إلى مجموعتين، مجموعة ضابطة (درست بالطريقة الاعتيادية) تألفت من (23) طالبا وطالبة ومجموعة تجريبية (درست بطريقة الت
المقدمة ومنهجية البحث
تتفق أغلب الأدبيات ومنها المحاسبية, بأن الخطوة الأولى في وضع وتقييم أي نظام إداري أو محاسبي هي في صياغة أهداف ذلك النظام لما لذلك من أهمية في توفير معيار للحكم على كفاءة التطبيق من عدمه.
وتعرف الأهداف بأنها (النهايات التي تعمل أو توجه النشاطات باتجاهها أو هي النهايات التي تطمح النشاطات تحقيقها). ( 1 ) ..,
كما تعرف أيضا بأنها (الأ
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مشكلة البحث :
تعد الادارة الجامعية عاملا مهما واساسيا في اكمال البناء المعرفي لشخصية الطالب الجامعي لما يمثله من قدرة على قيادة العملية التربوية والتعليمية والوصول بها الى تحقيق اهدافها . وطالما كانت هذه الادارة ممثلة ابتداء من رئاسات الاقسام ووصولا الى اعلى الهرم الاداري في الجامعة مهمة في تحقيق الاهداف العلمية والتربوية فان اختيار الاشخاص للقيام بمهامها تاخذ جانبا كبيرا ومهما وذلك للاثر
... Show MoreThis research deals with the attitude of oil press towards oil industry in the world and the extent of their concerns with the stages of oil industry relating to the abundance of oil and natural gas, as it is an international strategic and complementary industry. The researcher uses the survey method for content analysis of the initial article and the press news for two: years (2011-2012). The results if the study are as follows
1- Oil press is concerned with developing and the stages of the Arabic oil industry in the interest of OAPEC in the first place.
2- It is concerned with exploring, extracting, and marketing oil in the first place, then with refining operations in refineries and petrochemical plants in the second place, an