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 self-evident truth existing in today's business environment is the continuity of change and its continuity and turmoil, also its increase over time as it is more abundant, abundant, wide and complex than ever before, and it is the dominant feature in the business environment, as different organizations and operating units can find themselves shifting from the top to the bottom. And then it requires its departments to strive to adapt to these rapid and turbulent shifts and changes by bringing about a series of organizational and adaptive changes that are not limited to one organizational aspect only but rather include all organizational components. Accordingly, this research came to determine the readiness of public organizations to chan
... Show MoreCoronary artery disease (CAD) is a major health concern and leading of death in individuals with type 2 diabetes mellitus (T2DM). Glutathione S – Transferase(GST) are known for their broad range of detoxification and in the metabolism of xenobiotics . The role of functional variants of these genes in the development of various disorder is proven. We investigated the possible role of these variants in the development of CAD in T2DM patients. In this case – control study a total of 60 patients (T2DM = 30 ; T2DM – CAD = 30) and 30 controls were included. Serum lipid profiles were measured and DNA was extracted from the blood samples. Multiplex PCR for GSTT1/M1 (present / null) polymorphism, were performed for genotyping of study pa
... Show MoreBackground: To evaluate the effect of antierosive agents (10% Nano-Hydroxyapatite (NHA), 10% Casein Phophopeptide-Amorphous Calcium Phosphate (CPP-ACP), and combination of 10% NHA and 10% CPP-ACP) on loss of minerals from enamel surface of permanent teeth treated with antierosive agents when exposed to an acidic beverage and investigate the morphological changes of treated enamel surface after demineralization with cola based beverage under Scanning Electron Microscope (SEM). Materials and Methods: Sixty maxillary first premolars were randomly divided into four groups, 15 teeth for each group. Group I treated with 10% NHA, Group II treated with 10% CPP-ACP, Group III treated with 10% NHA and 10% CPP-ACP, and Group IV did not treat with any
... Show Moreيمكن القول ، أن أزمة الاستبعاد والخلاف بشان ولاية العهد شهدت ولادة النظام الحزبي الحديث في إنكلترا، واظهرت حالة جديدة للتنظيم والدعاية الحزبية وادخال طرق جديدة للتأثير في الرأي العام في اثناء الانتخابات، واختلفت تلك الاحزاب في ايديولوجياتها فحزب الويك كانت له ارتباطات دينية بين اعضائه مع البيورتان أذ تشاركوا في مفاهيم حرية التعبير عن الرأي ومقاومة هيمنة رجال الكنيسة المتنفذين، في حين كان حزب التور
... Show Moreابعاد الجودة في السيطرة على العدوى المكتسبة في المستشفيات الحكومية العراقية: دراسة تقويمية
This research submitted to be a clear form for a city has famous civilization extended many centuries , made its obvious stamps & prominent for eyesight through what left us of edifices stated witnesses of Islamic cities , that are distinguished from others by its model , engineering of buildings that are taken special characteristics display thought creativity features & Islamic Arabian art , and this research clarifies from thought & design of Al-Hajjaj in building Wasit City that appeared as a result from the political conditions that Iraq faced them in general , and Al-Hajjaj in particular , the increasing of revolutions from different governorates
Objective: To suggest a weighted measure to diagnose the reasons for the low student success ratios in mathematics concerning the third grade of intermediate schools in light of components educational system represented by: [Students, Teachers, Curriculum, and Environmental reasons (others reasons)] assuming differentiated and interrelated components, Also the effectiveness forming of these components according to the gender variable. Methods: Data collection tools were prepared by constructing two questionnaires for each of (Students and Teachers), which included a number of items that involved some domains for studied components of educational system, which demonstrated a high level of validity and reliability in the pilot study, in addi
... Show MorePerhaps one of the most pillars in building communities, and to achieve consistency between its members, is the volunteer work, he is a humanitarian exercise been closely associated with all the meanings of goodness and righteousness since ancient times, but it differs in size and shape and motivations and trends from one community to another, and from time to time; while at least in the stages of calm and stability, it increases in disasters and calamities and wars times, and perhaps (the popular crowd) is the best proof of that, they answered a call reference, and volunteered to defend their land and their holy places. In terms of form it may be donating money or effort or profession or otherwise, either in terms of the trend may be di
... Show MoreClass consciousness represents its highest stage in the contemporary Marxist thought of Rosa Luxemburg and Antonio Gramsci, not just a reflection of reality, but rather a dialectical form through the reflection of consciousness on reality and its reproduction. The superiority over the infrastructure (historical materialism) promised the revolutionary class consciousness to be achieved spontaneously, and the seeds of a breakthrough are mass strikes, denying the role of the party to organize this awareness, limiting its role to the interconnection between classes, emphasizing the role of socialist democracy as a conscious vanguard for organizing spontaneity, struggle, and developing awareness during the revolutionary process and the leader
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