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.
هدف البحث إعداد تدريبات تزامن ما بين السايكو وتمرينات القوة الوظيفية للاعبي كرة القدم، والتعرف على تأثيرها في القدرة الانفجارية للرجلين، وفي مهارتي المناولة الطويلة والركلة الركنية للاعبي كرة القدم، ليفترض الباحث بإنه توجد فروق ذات دلالة إحصائية بين نتائج الاختبارات القبلية والبعدية لمجموعتي البحث التجريبية والضابطة في كل من القدرة الانفجارية للرجلين لمهارتي المناولة الطويلة والركلة الركنية في كرة القد
... Show Moreتواجه المؤسسات المختلفة تحديات كثيره تختلف نوعيتها باختلاف توجهات المؤسسه سياسيه او اقتصادية او اجتماعيه ... مما يشكل تهديدا لوجود المؤسسة وسمعتها وبخاصه عند تحول تلك التحديات الى ازمات يجب على المؤسسه التعامل معها والسيطره عليها واحتوائها وهنا ياتي دور ادارة العلاقات العامه في المؤسسه المعنيه للعمل والقيام باعداد برامج خاصه بالتعامل مع الازمات وهو مايعرف ببرامج اداره الازمات . وبطبيعة الحال تختلف عملية
... Show MoreThis research aims to improve the process Tax accounting by using the scientific method to such as Six Sigma DMAIC steps called in General. Authority for Tax accounting . this approach has been described Tax accounting process Fully and identify problems experienced by the measurement and analysis and identify the critical success factors to satisfy customers and adoption process redesign Tax accounting process with the possibility of obtaining a high-quality revenue to be used by the body to improve its performance . Collected data and information from interviews with officials, staff and see the details & the conduct & operations in the body, and used well as a questionnair to measure the quality & services present action b
... Show MoreThe research deals with the Presidents of the Christians who called themselves (Ghaltka) in the book titled (orient chirsy patriarchs) that talked about their scientific practical biography adding to) that their completeness on the position of Ghaltka with its decrees and caliphs who were contemporaries to them ,as well as their places, deaths, cemeteries and their accomplishments In accordance with the powers granted to them and also it mentions the situation of The Abbasid caliphate with them and with the sons of their sect .
The research aims to identify the risks faced by projects and work on the administration, such as those risks by using professional Project Management System (Project Management Professional) by identifying those risks and their impact on the objectives of the project, if they occur and to provide appropriate responses to Ha.autam search application on the draft Law Faculty port by the General Mansour Construction Contracting company has been using a method personal interview with the heads of departments and project managers in the Al-Mansour and tools descriptive and quantitative analysis as was used (likelihood and impact of risk analysis, Ai_kaoa scheme Sbb- effect, analysis of probability and impact, risk matrix (probability
... Show MoreThis study aimed to isolate and identifye the growth of microorganisms and
their effect on pickled cucumber and cabbage, the study also investigated the effect of
garlic (in the form of segments, chopped or crushed) on the mentioned pickled –food
features . Furthermore, a sense based comparison is made between vinegar-preserved
samples and vinegar-garlic preserved ones.
The following results have been obtained:
1- The isolation of staph. aureus alone from the samples and the study of its physical
and biochemical features.
2- The fresh garlic (segments, chopped and crushed) with concentration of 5%, 7.5%,
and 10% showed a damaging percentage of 100% to bacterial growth of staph. Aureus
after 24 hours of inc
This study discussed a biased estimator of the Negative Binomial Regression model known as (Liu Estimator), This estimate was used to reduce variance and overcome the problem Multicollinearity between explanatory variables, Some estimates were used such as Ridge Regression and Maximum Likelihood Estimators, This research aims at the theoretical comparisons between the new estimator (Liu Estimator) and the estimators
The research aims to clarify the importance of adoption of International Accounting Standard No. (12) "Income Taxes" as a tool for the measurement and disclosure of income taxes in the financial statements، and how to deal with the differences that arise as a result of difference in net profit accounting for net tax profit ،The problem of the research focused on the disparity between the income tax estimate in Iraq in accordance with the accounting standards and financial reporting and assessment of income tax in accordance with the tax laws and legislation, this discrepancy has led to the emergence of differences between accounting profit and tax profit (temporary differences and permanent differences) and these differences of w
... Show MoreCloth simulation and animation has been the topic of research since the mid-80's in the field of computer graphics. Enforcing incompressible is very important in real time simulation. Although, there are great achievements in this regard, it still suffers from unnecessary time consumption in certain steps that is common in real time applications. This research develops a real-time cloth simulator for a virtual human character (VHC) with wearable clothing. This research achieves success in cloth simulation on the VHC through enhancing the position-based dynamics (PBD) framework by computing a series of positional constraints which implement constant densities. Also, the self-collision and collision wit
... Show MoreIn the article we consider features of official style, its functions and factors which influence the definition of the style. The topicality of the issue can be explained by rapid development of market economy which affects in its turn business correspondence. In this regard, there are a lot of cliché, terms and professionalisms appeared recently. Only correct usage of them can serve as a key to successful communication in Russian as well as other languages. This work highlights documents that are part of the diplomatic style such as declarations, credentials, notes, resolutions and other documents. The administrative style can include orders and instructions.
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