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).
Corpus linguistics is a methodology in studying language through corpus-based research. It differs from a traditional approach in studying a language (prescriptive approach) in its insistence on the systematic study of authentic examples of language in use (descriptive approach).A “corpus” is a large body of machine-readable structurally collected naturally occurring linguistic data, either written texts or a transcription of recorded speech, which can be used as a starting-point of linguistic description or as a means of verifying hypotheses about a language. In the past decade, interest has grown tremendously in the use of language corpora for language education. The ways in which corpora have been employed in language pedago
... Show MoreThis paper aims to decide the best parameter estimation methods for the parameters of the Gumbel type-I distribution under the type-II censorship scheme. For this purpose, classical and Bayesian parameter estimation procedures are considered. The maximum likelihood estimators are used for the classical parameter estimation procedure. The asymptotic distributions of these estimators are also derived. It is not possible to obtain explicit solutions of Bayesian estimators. Therefore, Markov Chain Monte Carlo, and Lindley techniques are taken into account to estimate the unknown parameters. In Bayesian analysis, it is very important to determine an appropriate combination of a prior distribution and a loss function. Therefore, two different
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رمت الدراسة التعرف بمستويات التفكير الهندسي لدى طلبة قسم الرياضيات في كلية التربية / ابن الهيثم - جامعة بغداد، ولتحقيق هدف الدراسة تم اعتماد مقياس الحربي(2003) المعد على البيئة السعودية ويتكون من (25) فقرة موزعه على خمسة مستويات وهي (المستوى البصري ، التحليلي ، شبه الاستدلالي، الاستدلالي، المجرد وبلغت عينة الدراسة (206) طلاب من طلبة قسم الرياضيات في كلية التربية- ابن الهيثم بجامعة بغداد تم اختيارهم بالطريقة ال
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Les sociétés d’assurances sont considérées parmi les importantes entreprises financières non bancaires.
Pour que ces sociétés assurent sa continuité d’existence, il faut qu’elles veillent au rendement financier qui représente ses différentes actions durant une période déterminée, en effectuant une évaluation permanente en utilisant de différentes méthodes parmi lesquelles l’analyse financière avec ses aspects divers.
L’objectif de cette étude est d’évaluer le rendement financier des sociétés d’assurances et où projette l’étude sur la société Algérienne d’assurance durant la période 07- 09.
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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Sloped solar chimney system is a solar chimney power plant with a sloped collector. Practically, the sloped collector can function as a chimney, then the chimney height can be reduced and the construction cost would be reduced.The continuity, Naver-stockes, energy and radiation transfer equations have been solved and carried out by Fluent software. The governing equations are solved for incompressible, 3-D, steady, turbulent standard model with Boussiuesq approximation to develop for the sloped solar chimney system in this study and evaluate the performance of solar chimney power plant in Baghdad city of Iraq numerically by Fluent (14) software with orking conditions such as solar radiation intensity (30
... Show MoreThe Research topic seeks to analyze the "political risk and its component Terrorism Index," which consists of five indicators index, a number of terrorist operations, and the number of dead and wounded, and the size of the physical losses, based search sub-index analysis of material losses for the index terrorism and its impact on the indicators listed on the Iraq Stock Exchange Finance. As for the practical side, it has been use style gradient unrestricted and link the sample represented by ten banks listed on the Iraq Stock Exchange. was Statement the correlation and interaction of variables of the studySearch results produced that the volume of material losses is the most important indicator in the influential force and it explain a v
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The estimation of the parameters of Two Parameters Gamma Distribution in case of missing data has been made by using two important methods: the Maximum Likelihood Method and the Shrinkage Method. The former one consists of three methods to solve the MLE non-linear equation by which the estimators of the maximum likelihood can be obtained: Newton-Raphson, Thom and Sinha methods. Thom and Sinha methods are developed by the researcher to be suitable in case of missing data. Furthermore, the Bowman, Shenton and Lam Method, which depends on the Three Parameters Gamma Distribution to get the maximum likelihood estimators, has been developed. A comparison has been made between the methods in the experimental aspect to find the best meth
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The individual average income is considered one of the most used criteria for the distinguishing between the developed and the developing countries, for this reason the efforts of economic development has been construed on increasing the average national income, the investment expenditures is considered one of the basic foundations for economic development operation which lead to the expanding the prodection power of the economy, and increasing the level of national income in an averages greaten than the primary expenditures due to the work and interaction between the multiplier and the accelerator. But the ability of the economic sectors in the generation of national income as a result of the primary expenditures is different fr
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God Almighty singled out Arab nation to carry divine messages، and make them the land of Iraq to store the soil prophets and apostles and grandchildren of Al al-Bayt، peace be upon them as they were and are still a beacon for people، Shrines and monuments and flags، frequented by science students from various walks of life، were are shrines representing the name of Iraq by the private and the nation of Islam in general، sung by the preacher and artist and writer