Computational study of three-dimensional laminar and turbulent flows around electronic chip (heat source) located on a printed circuit board are presented. Computational field involves the solution of elliptic partial differential equations for conservation of mass, momentum, energy, turbulent energy, and its dissipation rate in finite volume form. The k-ε turbulent model was used with the wall function concept near the walls to treat of turbulence effects. The SIMPLE algorithm was selected in this work. The chip is cooled by an external flow of air. The goals of this investigation are to investigate the heat transfer phenomena of electronic chip located in enclosure and how we arrive to optimum level for cooling of this chip. These parameters, which will help enhance thermal performance of electronic chip and flow patterns, through the understanding of different factors on flow patterns. The results show the relation between the temperature rise, heat transfer parameters (Nu, Ra) with (Ar, Q) for two cases of laminar and turbulent flows.
The use of the word “war” alone raises horror and fear in the hearts of the recipients, especially if this war aimed at human’s life, his health and his future. It is the electronic advertising war among rival international companies that use cyberspace to create fear and horror in the hearts of the recipients because it connects the use of the product with human’s death or serious illness.
The problem of this research sheds light on the new uses of cyberspace which fucked by international companies to strike the interests of each other by displaying the defects of their products and its negative impact on citizen’s life. Despite the fact that those wars have opposed strongly, there are supporters for those wars. Their argu
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Mass transfer was studied using a rotating cylinder electrode with different lengths of legs acting as turbulence promoters. Two types of rotating cylinder ,made of brass, were examined : an enhanced cylinder one, with four rectangular extensions 10 mm long, 10 mm wide, and 1mm thick, and an enhanced cylinder two with four longitudes 30 mm long,10 mm wide, and 1mm thick. The best performance was obtained for enhanced cylinder two at low rotation speeds while enhanced cylinder one was realized at high rotation speeds. The mass transfer enhancement as compared with a normal rotating cylinder electrode, devoid of promoters, is 53% or 58% higher. The enhancement percentage decreased as rotation speeds increased further, since, seemingly, ful
... Show MoreStill Financial institutions, including banks, a key target for money launderers to transfer illicit funds to the legitimate funds and by weaknesses in the internal audit procedures applied in the banks or through a lack of legal structure to combat this phenomenon in addition to the procedures by other regulations
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ينقسم الاتجاه الأساسي الذي يجري مناقشته في هذه الورقة إلى مستويين: الأول يركز على تحديد مضمون العلاقة بين الشفافية والفساد، فضلا عن توضيح الدور الذي يمكن أن تؤديه أخلاقيات الأعمال، لتثار التساؤلات هي: هل أن الشفافية والفساد متغيرين مرتبطين معا؟ وهل تؤثر الشفافية في الفساد؟ وهل أن وجود الشفافية كفيل بإزاحة الفساد، أم نحتاج إلى شيء أخر يدعم عملية الشفافية؟ وإذا تم التحدث عن الشفافية كمصطلح بدون وجود مما
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The Arab woman expressed the life of oppression that she suffers from in her masculine environment, as she expressed her linguistic abilities with eloquence and intelligence, as she did not neglect philosophy, wisdom,
The Arab woman expressed the life of oppression that she suffers from in her masculine environment, as she expressed her linguistic abilities with eloquence and intelligence, as she did not neglect philosophy, wisdom, and exhortation
The research seeks to find the relationship between psychological flow and futuristic thinking among postgraduate students. To this end, the researchers have made up two scales: one scale to measure the psychological flow which consisted of (32) items and the other to measure the futuristic thinking included (39) items which were distributed into three domains. As to collect the required data, the two scales had applied on a sample comprised (200) postgraduate students. The findings revealed that there is a correlation between psychological flow and futuristic thinking. The researcher recommended the coming studies take the relationship between psychological flow and psychological happiness.
