One of the most important phenomenon that occurs in sheet metal forming processes is the spring-back, which causes several geometrical alterations in the parts. The accurate prediction of springback after bending unloading is the key to the tool design, operation control, and precision estimate concerning the part geometry. This study investigated experimentally the effect of pretension in three rolling direction (0, 90, 45 degree) on the springback behavior of the yellow brass, sheet under V shape bending die. The pre-tension ranges from five different levels starting of 11% to 55% from the total strain in each rolling direction by regular increase of 11 %, then bent on a V-die 90 degree for the springback estimate. From experiment the results revealat that the springback increment with increase pretension ratio and the springback in 45° rolling direction is considerable than the sbringback in 90° rolling direction and the springback in 90° is greater than the sbringback in 0° rolling direction.
الجمود المؤسسي واثره في فشل التنمية السياسية : محاولة من اجل بناء مفهوم
The Negro minority in the United States is associated with social injustice,
political deprivation, and economic oppresion. Its members felt that they are
second-class citizens, and that the acceptance of such status will lead to the
continual oppresion of the Whites upon them. As a result, the educated community
adopted a process to put a framework to their opposition to the former's injustice.
This organised framework is exemplified in the "Niagara Movement," which is
regarded as the first national organisation for Negros. The topic of this study is
chosen due to its historical and political significance.
The study consists of an introduction and five sections. The first section
addresses the preliminaries an
This study attempts to highlights on the evaluation of performance efficiency for Investments in both National & Iraqi Insurance companies for the years 2001-2010 and their importance on those companies and the economy of the country in order to find out the investment areas and to compare between investment activity and its revenues as well as to compare performance of both companies in investment field.
The study was based on annual reports and balance sheets of both companies. In many chapters, this study dealt with theoretical and practical aspects of the investments and its revenues. Key hypothesis was based on this study, including four parts of Sub hypotheses about (statistical effective relationship between the
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اهتمت المجتمعات العالمية في الآونة الأخير بفئة الأطفال ، ورعاية الطفولة وذلك لما لها من أهمية كبيرة في مستقبل المجتمع ، وتنميتة وتقدمه . لأنها يعتمد عليها في تقدم وتطور المجتمع فـي جميع المجالات الاقتصادية والاجتماعية والثقافية . ومن هنا ارتبطت الطفولة بالحياة برباط عضوي فالأطفال براعم الحياة ومع هذه البراعم تستمر الحياة لذلك اهتمت دول العالم بوضع البرامج وعقد المؤتمرات من اجل النهوض
... Show Moreولد ابو بكر محمد بن زكريا الرازي في الري سنة 250هـ (864م) وتعمق في الطب والكيمياء والفلك والأدب والفلسفة وهو أحد مشاهير الاطباء في زمانه وهذا هو السبب الذي دعاه لأن يتنقل من بلاط الى اَخر , ولم ينعم بالأستقرار في حياته بالنظر الى تقلب الأهواء والاُمراء وأضطراب الأحوال السياسية . قام برحلات كثيرة , وعهدت اليه ادارة بيمارستان ( مصح ومشفى ) الري ثم قام بهذه المهمة نفسها في بغداد.
لقب بـ( طبي
... Show MoreThe fact of having Journalism being open to people from different orientations professions, working as journalists requiring protection just to spread corruption, is one of the biggest threats faced by journalism.
Journalists noticed the spread of unprincipled journalists with no journalistic ethics amongst them, they tried to protect their profession from these corrupt outsiders who might annihilate the mighty of journalism. The principles of the journalism profession known as journalistic ethics, are one the most important formulations of the law concluded by the journalists and those concerned by the the profession, they were then published in public in order to prove their professionalism, especially for those who don’t und
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عملية صناعة واتخاذ القرار في السياسة الخارجية للرئيس جورج والكر بوش