The aim of this work is to perform an experimental study for the effect of forced vertical vibrations on free convection heat transfer coefficient, from flat plate made of Aluminum with dimension (300 Length*100 Width*3 thickness mm).It's heated under a constant heat flux of (250-1500 W/m2 ) upward. The flat plate was located horizontally or inclined in multiple angles at rang of (0o , 30o , 45o 60o ، 90o ). The experimental study is carried out at a range of frequency (2-16 Hz) ، the amplitude at the range of (1.63-7.16 mm), and the Rayleigh number at the rang (138.991< Ra <487.275).
The results of this study show that, the relation between the heat transfer coefficient and the amplitude of vibration is incrementally for inclination angles from (0°-60°), and reaches a maximum ratio of (13%) in the horizontal position, except at the vertical position (θ=90o ) the heat transfer coefficient decreases as the vibration response increases and the maximum decrease ratio occurs at (7.6 %)
The research illustrated that the theory of constraints is "A group of concepts and basics that aim at helping the management in order to determine the difficulties and how to overcome these difficulties through determining the necessary change and how these change can be done efficiently and effectively ".
The research showed that the theory of constraint including its tools calls for magnifying throughput, constricting the product cycle , determining the optimal production mix , utilization of scare resources and canceling the idle time , that achieving throughput increasing then increasing profit .
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... Show Moreالمستودع الرقمي العراقي. مركز المعلومات الرقمية التابع لمكتبة العتبة العباسية المقدسة
This work is devoted to a comparative study of the phenomenon of enantiosemy in Russian and Arabic.Everyone knows the term antonyms - words of the same part of speech, opposite in meaning, such as: Day and night, white and black, truth and lies. But in Russian, Arabic and other languages there is an interesting phenomenon, which consists in the fact that one word has two opposite meanings. Such a phenomenon in linguistics is called enantiosemy (from the Greek words enantios - "opposite" and sema - "sign")
هدفت الدراسة الى التعرف على تأثير التمرينات الخاصة في تطوير بعض القدرات البدنية وأداء المهارات الدفاعية الفردية لدى افراد عينة البحث، اذ أستخدم الباحثان المنهاج التجريبي بتصميم المجموعة الواحدة ذات الاختبار القبلي والبعدي، وأختار الباحثان مجتمع البحث بالطريقة العمدية لاعبي منتخبات تربية في محافظة بغداد وعينة البحث تكونت من لاعبي منتخب تربية الكرخ الأولى والبالغ عددهم (12) لاعباً، وتم اختيار عينة البح
... Show MoreYehuda Steinberg is a Russian writer who drew his culture and education from Eastern Europe's neighborhood and village atmosphere, especially in Russia. He spent his life traveling between the forests and mountains of Besravia, Where the scenic landscape affected him greatly. It is evident clearly in most of his stories when he describes the mountain, alleys, lake, and forest. Most readers think for the first time that these stories are nothing but programs to describe nature. Steinberg attempted to link the surroundings with his political and literary tendency. Even though he had never been to Palestine, it was observed that he glorified Palestine in some of the chapters and paragraphs of his stories. It was a predominant phenomeno
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