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.
المستخلص
يهدف هذا البحث إلى تصميم ومكننة نظام متطور لتقويم جودة العملية التعليمية للجامعات العراقية، باعتماد مدخل الجودة، ومكننة نظام معلومات قادر على توفير البيانات بالخصائص المطلوبة التي يمكن الاستناد إليه في اجراء عملية التقويم على وفق النظام المقترح.
اعتمد البحث على أسلوبيّ دراسة الحالة والدراسة التطبيقية، للوصول إلى النتائج ا
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(January 25, 2011) represented a real opportunity to bring about fundamental changes in Egyptian foreign policy and to start a new phase that would cut off all the negative and problematic aspects of Egyptian politics in the period before the revolution. Through the employment of Egypt's huge balance and the role of historical is a civilization rooted in the roots of thousands of years and Islamic reference represented over more than a thousand years the Islamic medium of religion in the start of vision and tools to achieve the Egyptian national interest, and safeguarding Egyptian national security in its comprehensive sense. The research attempts to answer a central question: Is there a role for Egyptian soft power in the Islamic world
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تناولنا في بحثنا أحد اساليب البرمجة الخطية وهي الطريقة المبسطة لتقدير معلمات انموذج الانحدار الخطي عن طريق اختيار دالة الهدف التي تعمل على تقليل الحد الادنى لمجموع الاخطاء الناتجة من تقدير المعلمات بطريقة المربعات الصغرى الاعتيادية ( OLS) حيث سيتم في الطريقة المبسطة ( simplex) فرض قيود على نفس الاخطاء نفسها بهدف تصغيرها الى اقل ما يمكن للحصول على تقديرات افضل لمعلمات انموذج الانحدار الخطي . على اساس ان طريقة المرب
... Show MoreThe creative arts in general and the theatre in specific represent man's rushing and carving for freedom, goodness and beauty, and the relation between creativity and freedom has always been fluctuating following the censorship pressures of all types and shapes the political, religious and social. Since the theatre is the closest and more touching creative art to the problems of the society of numerous types and levels and it was and has always been playing an enlightening role in shedding light on what the societies experiencing with crises and problems in all directions. The theatre, thus, derives the essence of existence from life, through topics concerned with what the human being is. It seeks to be the real witness and partne
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ﺔﻴﻋﺍﺫﻹﺍ ﺕﺎﻴﻨﻘﺘﻟﺍ ﻡﺍﺪﺨﺘﺳﺍ ﰲ ﲑﺒﻛ ﺭﻮﻄﺗ ﻦﻣ ﻝﺎﺼﺗﻻﺍ ﺮﺼﻋ ﻩﺪﻬﺷ ﻱﺬﻟﺍ ﺖﻗﻮﻟﺍ ﰲ ﺔﻴﻧﻮﻳﺰﻔﻠﺘﻟﺍﻭ ﺍ ﺢﺴﻓ ﰲ ﻢﻬﺳﺃ ﺕﺎﻄﶈﺍ ﺀﺍﻮﺳ ﺔﻴﻧﻮﻳﺰﻔﻠﺘﻟﺍ ﺕﺍﻮﻨﻘﻟﺍ ﺚﺒﻟ ﻊﺳﺍﻮﻟﺍ ﻝﺎ ( ﺔﻴﺿﺭﻷﺍ ﺔﻴﻠﺑﺎﻜﻟﺍ ﻭﺃ ﺔﻴﺋﺎﻀﻔﻟﺍ ﻭﺃ ( ﱵﻟﺍ ﺔﺻﺎﳋﺍ ﺔﻴﺋﺎﻀﻔﻟﺍ ﺕﺍﻮﻨﻘﻟﺍ ﻦﻣ ﺪﻳﺪﻌﻟﺍ ﺭﻮﻬﻇ ﰲ ﺎﻀﻳﺃ ﺪﻋﺎﺳ ﺎﳑﻭ ، ﺕﺎﻴﺋﺎﻀﻔﻟﺍ ﺭﻮﻬﻇ ﻚﻟﺫ ﻞﺒﻗ ﺩﺎﺳ ﻥﺃ ﺪﻌﺑ ﺔﻴﻣﻮﻜﺣ ﲑﻏ ﺕﺎﻴﻌﲨ ﻭ
... Show MoreThe study included three topics, the definition of the personality of Imam al-Bazazi, his scientific biography, his elders, his writings, his students and his death, selected issues of his weightiness related to purity, and the Imam al-Bazazi is Muhammad ibn Muhammad ibnShihabibn Yusuf, known in al-Kardari al-Hanafi al-Balzazi. The other doctrines, the author relied in his book on the sources of the previous scholars of the Hanafis, and make them the basis in his book, the author did not adopt the definitions of language and terminology, and rarely mention the evidence Shariah adopted by scientists in their opinions, and limited to mention only opinions, In front of the first issue spotlessly water user, and the second issue that sleep l
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