Natural convection in a trapezoidal enclosure with partial heating from below and symmetrical cooling from the sides has been investigated numerically. The heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1/5, 2/5, 3/5, 4/5 are considered. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations discretized by finite volume method; body fitted coordinates are used to represent the trapezoidal enclosure, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass. The range of Rayleigh number is (103≤ Ra ≤105) and Prandtl number is 0.7. The results show that the average Nusselt number increases with the increases of the source length.
The theory of the psychologist’s Piaget states that man passes through four stages; other says that mankind passes through five. At each stage, human learn new characteristics, values, skills, and cultures from different environment that differ from one society to another. Therefore, the cultures of societies vary according to the diversity of the environments. These environments also vary depending on the circumstances surrounding them, e.g., in war environment, the individual learns what he does not learn from living in safe environment. As the environment changes, the communicative message also changes. This message is subject to person, groups, organizations and parties and directed to a diverse audience in its orientations and bel
... Show MoreNuclear shell model is adopted to calculate the electric quadrupole moments for some Calcium isotopes 20Ca (N = 21, 23, 25, and 27) in the fp shell. The wave function is generated using a two body effective interaction fpd6 and fp space model. The one body density matrix elements (OBDM) are calculated for these isotopes using the NuShellX@MSU code. The effect of the core-polarizations was taken through the theory microscopic by taking the set of the effective charges. The results for the quadrupole moments by using Bohr-Mottelson (B-M) effective charges are the best. The behavior of the form factors of some Calcium isotopes was studied by using Bohr-Mottelson (B-M) effective charges.
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Abstract
The study deal with two main variables:- the dimensions of distribution, and the customer loyalty . the researcher has chosen samples of Iraqi newspapers like (AL Sabah, AL Mada, AL Bayna aljdeida newspaper), because this product depends greatly on the consumption of customers so as to achieve the success. After studying the dimensions of these variables ( cost, flixibilty & deliver time ) which concerns the distribution, and for these dimensions ( marketing relationship, customer perception, customer experience, brand, & product quality) which relate to the customer loyalty . the problem has been identified in a number of remarks concerning the extent of awareness that the administration
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يهدف البحث التعرف على اثر استراتيجية القوائم المركزة في تحصيل مادة الكيمياء عند طلاب الصف الثاني المتوسط وتم استخدام المنهد التجريبي ذو الضبط الجزئي وكذلك تم اختيار مجامع البحث جميع طلاب المدارس الثانوية والمتوسطة التابعة لمديرية تربية كربلاء
The increase in military spending has become a feature of the times for many countries, including China. They have sought to increase their defence spending, not with the aim of domination and possession, but rather to protect their economic interests and to secure their foreign trade. The research aims to identify the impact of military spending by studying the nature of defence spending and its role in providing security. And stability and facilitating foreign investment in it, as well as storming the military industry, securing some humanitarian supplies, and participating in a variety of public works that can be used in the civil and military fields, and the aim of the research is to id
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تستخدم تقنيات التصنيفِ ًبصورة واسعة جدا في كثير من المجالات التطبيقية. ولاسيما في المجالات الاقتصادية والتحليلات المالية كما في عِلْمِ تحليل الزبونِ التنبؤيِpredictive customer analytics ، الذي يتضمن ذلك الإمتلاكِ، المقايضة، إحتكار وإحراز الإئتمانِ والجباياتِ. إنّ هدفَ أيّ نموذج تصنيفِ هو أَنْ يُصنّفَ َ المشاهدات في مجموعتين أَو أكثرِ للوصول الى التنبؤ بنتيجةً ترتبط بكُلّ مشاهدة ومثا
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يعيش المجتمع العالمي أزمات بنيوية ونسقيه عميقة واختلالات وظيفية أسهمت في تنامي مظاهر الصراع المختلفة واشتداد تفجر الأزمات الهوياتية وتزايد الامراض الاجتماعية المقضة للعيش المشترك والمربكة لمظاهر التعايش والتآلف مع لجوء إنسان العصر الحالي الى التقوقع والاحتماء والانزواء تحت هويات ضيقة ونحل صغيره في مشهد يظهر مدى تراضي شبكة العالقات الاجتماعية على أداء وظائفها وأصبح عندها الاغتراب والقلق واللاتضامن والع
... Show Moreان مرتكزات السياسة الخارجية العراقية لمرحلة ما بعد العام 2003 قد عكست توجهات ايجابية قادت الى صياغة مجموعة من الرؤى والتصورات الاستراتيجية الجديدة التي افضت الى اعتماد وتوظيف الوسائل والقنوات الدبلوماسية بوصفها وسائل فعالة وبطريقة متكاملة ومتوازنة من اجل تعزيز مستويات الاداء الفعلي وتحقيق جميع الاهداف المستقبلية للسياسة الخارجية العراقية في ضوء صياغة معادلة مفادها: تدعيم وترصين اداء مؤسسات صنع السياسة ال
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