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.
Graph is a tool that can be used to simplify and solve network problems. Domination is a typical network problem that graph theory is well suited for. A subset of nodes in any network is called dominating if every node is contained in this subset, or is connected to a node in it via an edge. Because of the importance of domination in different areas, variant types of domination have been introduced according to the purpose they are used for. In this paper, two domination parameters the first is the restrained and the second is secure domination have been chosn. The secure domination, and some types of restrained domination in one type of trees is called complete ary tree are determined.
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The international field has witnessed economical and technological developments which made the world one market . this increased the competence among the international dealers . the market, thus comprises states, governments, international organizations, and giant economic blocs which all seek to unify the behavior of the game by dealing and seizing the opportunities and facing the threats which concern deregulation in all its forms .This led to a number of developments including the increasing number of mergers and posts which are considered investment alternatives. &nb
... Show MoreIt was the sayings of Andalusia scholars in agriculture based on experiments and theories that helped a lot in the success and development of agriculture in the Andalusia ,and also The divisions of the soil and out types and forms it helped a lot of to know arable of non-arable land earth and all off the determination of the color of repentance is important often discovered by agricultural scientists and that helped in the cultivation of certain crops in certain land without another land.and though each particular agricultural crops specific soil in which to live and not live in other soil ,
The energy consider generally and specifically the petroleum energy
from the prior requirement of the population and nations, and the basics of the
survival of mankind and all the challenges for the sake of continuum, so
without this energy the life of ankind being varied, so far the life is still as a
fact on the planet earth, and suppose the life may continue as the willing of
Allah ,that the events and the standards and the degree of development is still
as it is, in another word no any technical developments and no any
entertainment no transportation and also there is no demographic domination
for the whole lands belonging to Allah, certainly no way to talk more on what
we and the others knew, what is the g
It was the sayings of Andalusia scholars in agriculture based on experiments and theories that helped a lot in the success and development of agriculture in the Andalusia ,and also The divisions of the soil and out types and forms it helped a lot of to know arable of non-arable land earth and all off the determination of the color of repentance is important often discovered by agricultural scientists and that helped in the cultivation of certain crops in certain land without another land.and though each particular agricultural crops specific soil in which to live and not live in other soil
Fraud crimes, which is a form of crimes against the funds in public office, is one of the crimes of traditional and cutting-edge in the same time, but it took a distinct character from other traditional crimes because of what is based upon, behavioral fundamentals and foundations and expressive image of personal qualities, concentrated in the mental work, the inventive sophistication, and skillful abilities of the perpetrators of these crimes, in addition to what is owned by crooks today a behavioral ability represented in underestimating laws and instructions. Fraud is considered one of the organized crime methods It is the most important method of its methods, all crimes practiced by the cro
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يعتبر مفهوم المجتمع المدني من بين سلة المفاهيم التي حملت لوائها واعادت رفعها حركات الموجة الثالثة من الديمقراطية في العالم التي نادت بالتعددية والانتخابات الحرة ...الخ .
يصصقلا بدلاا يف اهتيمهاو اهرود ةكبحلا عوضوم ىلع ءوضلا ثحبلا طلسي لكشب يتاروتلا يصصقلا بدلاا يف ةكبحلاو ماع لكشب اهبيكارتو اهعاونا ثيح نم ضرع نم أدبي يذلا يمرهلا لسلستلاو ةصقلا رصانع مها زارباب ثحبلا متها .صاخ يلاتلابو ةورذلا ةطقن ىلا ً لاوصو ثادحلاا ديقعتو تاعارصلاو ، )ةمدقملا( ثادحلاا نوكت نا اما ةياهنلا كلتو ةصقلا ةياهن ىلا لاوصو تامزلاا كلت لحل طوبهلا أدبي .ةمزلاا لحل لصت ةقلغم ةياهن وا هسفنب ةياهنلا را
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