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.
The propagation of laser beam in the underdense deuterium plasma has been studied via computer simulation using the fluid model. An appropriate computer code “HEATER” has been modified and is used for this purpose. The propagation is taken to be in a cylindrical symmetric medium. Different laser wavelengths (1 = 10.6 m, 2 = 1.06 m, and 3 = 0.53 m) with a Gaussian pulse type and 15 ns pulse widths have been considered. Absorption energy and laser flux have been calculated for different plasma and laser parameters. The absorbed laser energy showed maximum for = 0.53 m. This high absorbitivity was inferred to the effect of the pondermotive force.
The parliamentary election is one of the features of democratic systems that give individuals the right to participate in government and political election-making. Typically, the process of parliamentary elections received wide attention from media, as well as attention from large segments of the public because they understand the vast importance to assume political positions and associated fates of people and their destinies. Its importance comes from the fact that it allows citizens the right to participate in managing the public affairs by granting their confidence and voices to the elected president or his representatives in the parliamentary.
Media task is to emerge democratic societies, in particular, in the mission of urging p
methodology six sigma Help to reduce defects by solving problems effectively, and works Lean to reduce losses through the flow of the manufacturing process and when integrating these two methodologies (Lean and six sigma), the methodology of Lean six sigma will form the entrance to the organizers of the optimization process and increase the quality and reduce lead times and costs . by focusing on the needs of the customer. this process uses statistical tools and techniques to analyze and improve processes.
We have conducted this research in the General Company for Electrical Industries and adopted its product (machine cooling water three taps) as a sample for research. In order to determine t
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تعد التنمية المستدامة حق للكل البشرية وانها تهدف لتطوير المجتمعات البشرية من كافة النواحي وبشكل دائم وهي تهدف في القضاء على الفقر والجوع وهذه الظاهر ظاهرة منتشرة في العراق اذ ان المواطنين فيه يعشون في حالات تفرقة ودائما هم في حالات حروب اويعيشون في حصار اقتصادي او في اوقات كثيرة يعشون باوقات ازمات مما يجعلهم في فقر دوري ارض لتطبيق هدف التنمية المستدامة الذي ينص على القضاء على ،
تهدف هذه الد ا رسة الى التعرف على السلوك التصويتي للمقترعات الع ا رقيات. والأسباب التي تدفعهن للمشاركة في عملية الاقت ا رع، والعوامل المؤثرة في خيا ا رتهن التصويتية والأسباب التي تجعلها تفضل اختيار الرجل أو اختيار ام أ ر ة ، وأخي ا رً مدى م ا رعاة اج ا رءات الاقت ا رع لظروف النساء واحتياجاتهن واهتماماتهن. اعتم دتالد ا رسة منهجاً وصفياً واستعان ت بطريقة المسح بالعينةاما الاداة الرئيسية فهي الاستمارة الاستبيانية.
... Show Moreيعد الأمن البيئي موضوعاً حيوياً لا سيما في العصر الحديث، حيث بدأت تحديات التغير المناخي تتدهور وبسرعة متزايدة. وتزداد أهمية هذا الموضوع مع تصاعد تلك التحديات، أذ يتعين على الجميع لا سيما النساء منهم المشاركة في الحفاظ على البيئة لضمان استدامتها للأجيال الحالية والمستقبلية. ويُعد الحفاظ على البيئة والموارد الطبيعية أمراً ضرورياً لضمان استدامة الكوكب ومستقبل الأجيال القادمة. وفي هذا السياق، يأتي دور المرأة
... Show MoreIslam paid great attention to the youth, and took care of them because they
are the strength and movement, which is the preferrence stage in human life,
and they are the ones who
يتناول البحث الحماية المدنية للمستهلك في المرحلة السابقة على التعاقد الالكتروني