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.
Writing in English language demands both mental skills and a suitable level of language proficiency. Some studies showed that writing anxiety has an impact on the acquisition of language learning. This study; however, teaches the cognitive strategies (PLAY & WRITE) as a writing strategy, so as to decrease students’ use of it when experiencing writing anxiety at the academic writing level. The sample has been (100) second-stage Department of English learners at the College of Education (Ibn –Rushd), in the University of Baghdad-Iraq. They have been randomly selected and divided into experimental and control groups; (50) students in each group. To achieve the objective of the study, SLWAI questionnaire has been distributed to the e
... Show MoreThe researcher used the experimental approach due to its suitability and the nature of the research problem. The research community was represented by the eighth-grade students in the Rozak Elementary Mixed School affiliated with the General Directorate of Education in Erbil / the center, for the academic year (2021-2022), the number is (96) students, and the research sample consisted of (63) male and female students, with (31) in the experimental group, and (32) in the control group, and (11) students were excluded by (5) students from the experimental group, and (6) students from the control group, as the excluded, are students who failed and were absent from the lessons, and accordingly, the research sample became composed of (52) mal
... Show Moreهدف البحث الحالي التعرف على فاعلية انموذج سكمب المعدل في الأصالة الرياضية واتجاه طلاب الصف السادس العلمي نحو البرهان الرياضي ، تَمَّ الاستعانة بالتصميم التجريبي ذي الاختبار البعدي والضبط الجزئي لمجوعتين متكافئتين (تجريبية وضابطة) ، تكونت عينة البحث من (55) طالباً من طلاب الصف السادس العلمي في ثانوية ابن الهيثم للبنين الواقعة في مركز محافظة القادسية ، جرى توزيع طلاب عينة البحث عشوائياً إلى مجموعتين إحداهما تج
... Show MoreTechnology is one of the important influences in the development of professions in general and the profession of tax auditing and examination in particular because of the importance of this section in the General Tax Authority because of the service it provides is auditing the financial accounts provided to the department by the taxpayers to ensure the correctness of revenue and the achievement of tax justice. Where the research aims at the importance of using electronic accounting information systems in developing the work of the Tax Audit and Examination Department, to reduce the difficulties that the department may be using using manual systems, which is the need for time and effort to accomplish it, and to develop methods and procedu
... Show Moreالتنمية المستدامة حق لكل البشرية وأنها مفهوم ٌ مركب من عنصرين هما التنمية واالستدامة مهمين متالصقين أي ال يوجد تنمية دون استدامة وال العكس يصح، وأنها تمتلك العديد دراسات سياسية وإستراتيجية من األهداف ويبرز هدف الـ)القضاء على الفقر، والقضاء على الجوع( ومن أهم أهدافها، هذه الظاهرة بارزة في المجتمع العراقي بسبب الحروب واالزمات المتكررة فيه وحاالت الحصار االقتصادي، وكذلك بسبب عدم توزيع موارده بشكل عادل من قبل
... Show MorePeaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established
The aim of this research is to know how business organizations achieve competitive advantage ,and make it sustainable through constructing a green strategy ( friend to environment) which is reflected on sustaining their competitive advantages .The problem of this study is presented through trying to answer many thoughtful questions, the most important of them are:
1-Can business organizations today make green strategies supporting their competitive advantage?
2-Is there a framework or mechanism could be depended on by business organizations to manage strategic risks of losing their competit
... Show MoreThe study aimed at identifying the strategic gaps in the actual reality of the management of public organizations investigated to determine the strategy used based on the study model. The study relied on the variable of the general organization strategy in its dimensions (the general organization strategy, the organization's political strategy and the defense strategy of the organization) The sample of the study was (General Directorate of Traffic, Civil Status Directorate and Civil Defense Directorate), formations affiliated to the Ministry of the Interior, for the importance of the activity carried out by these public organizations by providing them In order to translate the answers into a quantitative expression in the analysi
... Show Morethe history of Damascus by Ibn ' asaakir d. 571 a.h. 1272 m from local histories books concerned with male citizen narrators, to distinguish between rate and Rob them, this book is more a history of Islamic heritage books on Islamic City, and if we know that Ibn ' asaakir translated it for personal
The aim of this study was to know ( the impact of education differentiated strategy to modify the alternative developments of geographical concepts when students first grade average) .
To achieve the goal of this study , researcher relied on the experimental design of a partial set , the design is ( the experimental group with a control group of post-test ).
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