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.
عرض كتاب (وهم التحكم : القوة والسياسة الخارجية في القرن الحادي والعشرين)
The principal components analysis is used in analyzing many economic and social phenomena; and one of them is related to a large group in our society who are the university instructors. This phenomenon is the delay occurred in getting university instructor to his next scientific title. And as the determination of the principal components number inside the principal components depends on using many methods, we have compared between three of these methods that are: (BARTLETT, SCREE DIAGRAM, JOLLIFFE).
We concluded that JOLLIFFE method was the best one in analyzing the studying phenomenon data among these three methods, we found the most distinguishing factors effecting on t
... Show Moreتعمل البنوك والمؤسسات المالية كوسيط مالي بين أصحاب المدخرات والودائع من جهة ومستخدمي هذه الأموال من جهة أخرى، وممارسة هذه الوساطة المالية بين الطرفين توضح العلاقة التي ينشأ عنها الائتمان، فالائتمان علاقة بين طرفين أولهما تزيد موارده على احتياجاته وهم (المدخرون) والثاني تزيد احتياجاته على موارده وهم (المقترضون)، وطبيعة العلاقة التي تنشأ بينهما تأخذ أحد شكلين: مباشر دون وساطة من أي طرف خارجي، أو غير مباشر عن
... Show MoreThe goal of health awareness is to familiarize people with health information and facts, and make them realize their sense of responsibility towards their health and the health of others. And translate that goal in practice through applying healthy and sound behaviors spontaneously. This, the goal, is pursued by health awareness announcements through employing announcement persuasion of health as one of the methods of influencing the masses to adopt ideas, behaviors, and adherence to health advice and guidelines; The study aims to analyze the content of the Ministry of Health and Environment announcements regarding health awareness and to reveal the most employable persuasions in health awareness announcements
... Show MoreBased on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore
... Show MoreHuman Rights The word of graduation in the Arabic language to many meanings may be the most appropriate of what Al-Ragheb Al-Isfahani said in the right: is the coming of the thing from saying or doing at the time it must and in the form that must be, so the term human rights includes the following:First: A party has the right and another duty to.
الحديث عن محمد بن إسحاق النديم حديث عن عالم جليل كان له فضل تصنيف سفر خالد من أسفار المعرفة و العلم و سجل ضم عناوين ما أنتجته الأمة العربية الإسلامية في وقت عزها و مجدها و سطوع كوكبها في سماء الدنيا ، فجاء هذا الكتاب جامعا نافعا في بابه .
In the second millennium BC, the international community change at the ancient Near East, There has been a significant developments with the appearance of five kingdoms (Babylon, Assyria, Mitanni, Egypt, and Hatti) called themselves the (Great Powers) and their kings named (Great King), and Correspondence among themselves on behalf of (the brothers), to differentiate themselves from the small kingdoms Minor of them.
RÉSUMÉ
LeMauger Bleu est une méthode emblématique de l’enseignement traditionnel, qui présente une littérature française riche et patrimoniale, et dont l’objectif est de faciliter l’accès au texte par le vocabulaire et la grammaire et d’étendre la culture générale et littéraire de l’apprenant. La démarche (traditionnelle) est toujours la même : le texte, le vocabulaire et la grammaire, la traduct
... Show Moreتم التطرق إلى مفهومي الخجل والعنف الأسري لدى الفتيات ضعيفات السمع ومشكلة البحث تكمن بدراسة العنف الأسري لضعيفات السمع وعلاقته بالخجل ومعرفة ما يترتب عن ذلك بالنسبة للفتاة المراهقة ضعيفة السمع أثناء تعرضها للمعاملة السيئة وأثره على شخصيتها ، فالخجل هو نتيجة لأساليب التربية الخاطئة التي تعاني منها الفتاة ضعيفة السمع ، ويهدف البحث إلى التعرف على الخجل وعلاقته بالعنف الأسري لدى ضعيفات السمع في محافظة بغداد ، و
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