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

       The current research aims to build a training program for chemistry teachers based on the knowledge economy and its impact on the productive thinking of their students. To achieve the objectives of the research, the following hypothesis was formulated:

   There is no statistically significant difference at (0.05) level of significance between the average grades of the students participating in the training program according to the knowledge economy and the average grades of the students who did not participate in the training program in the test of productive thinking. The study sample consisted of (288) second intermediate grade students divided into (152) for the control group

The first chapter the importance of research and need for education scientists see that the roots of the use of a specimen Wheatley in learning and teaching back to Grayson Wheatley, one of the largest supporters of a modern construction, which lay the groundwork for the specimen stage and the form in which it is. That was attributed to him, often called his name called while some educators based learning strategy on the issue. He sees the learner in this model make him a meaningful understanding of problems during his progress, thereby acting with his colleagues to find solutions to them in small groups. He

        Borders Search: Search by students is determined by th

Random laser gain media is synthesized with different types of dye at the same concentration (1×10^-3 M) as an active material and silicon dioxide NPs (silica SiO₂) as scatter centers through the Sol-Gel technique. The prepared samples are tested with UV–Vis spectroscopy, Fluorescence Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX). The end result demonstrates that doped dyes with silica nanoparticles at a concentration of 0.0016 mol/ml have lower absorbance and higher fluorescence spectra than pure dyes. FESEM scans revealed that the morphology of nanocrystalline silica is clusters of nano-sized spherical particles in the range (25-67) nm. It is con

Proposals to raise awareness of the rights of minorities and secure their freedoms have begun to receive attention Internationally. It is escalated, especially after the increasing impact of wars and conflicts on these situations Minorities, and UNESCO stresses the need to take over information and communication policies Greater attention to protect minority rights.

Hence the importance of our research, the problem of which lies in the main question: (What is the role Radio Republic of Iraq has played in promoting awareness of minority rights at the level : Public and  Social?) . As one of the Iraqi media networks , laws oblige them to pay attention to the rights of minorities and to spread a culture of pluralism , diversity

The origin of occupations and trades producing goods and services necessary for the members of society
When people are designated to perform this task, in which case the state of change is included in the imposition of adequate labor rights, and may change from imposing sufficient to imposing the eye
Does the state have the right to compel "tradesmen and professions" to do their jobs?
Therefore, this research came to address the legitimacy of this from the perspective of the Islamic economy.

Abstract

Although the rapid development in reverse engineering techniques, 3D laser scanners can be considered the modern technology used to digitize the 3D objects, but some troubles may be associate this process due to the environmental noises and limitation of the used scanners. So, in the present paper a data pre-processing algorithm has been proposed to obtain the necessary geometric features and mathematical representation of scanned object from its point cloud which obtained using 3D laser scanner (Matter and Form) through isolating the noised points. The proposed algorithm based on continuous calculations of chord angle between each adjacent pair of points in point cloud. A MATLAB program has been built t

A solar updraft tower power plant (solar tower) is a solar thermal power plant that utilizes a combination of solar

air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity.

 This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatures. Three basements were used: concrete, black concrete and black pebbles basements. The study was conducted in Baghdad from August to November 2009.

The results show that the best chimney efficiency attaine

Abstract

This paper concerned with study the effect of a graphite micro powder mixed in the kerosene dielectric fluid during powder mixing electric discharge machining (PMEDM) of high carbon high chromium AISI D2 steel. The type of electrode (copper and graphite), the pulse current and the pulse-on time and mixing powder in kerosene dielectric fluid are taken as the process main input parameters. The material removal rate MRR, the tool wear ratio TWR and the work piece surface roughness (SR) are taken as output parameters to measure the process performance. The experiments are planned using response surface methodology (RSM) design procedure. Empirical models are developed for MRR, TWR and SR, using the analysis

Certain bacterial and viral infectious agents may play a role in the activation of inflammation in atherosclerosis lesions. Epidemiological studies indicate that infectious agents may predispose patients to atherosclerosis as Infections have been associated with an increased risk of this disease. Moreover, a positive antibody status has been detected against some infectious organisms associated with atherosclerotic rupture. Infectious agents found in human atheroma, which may directly cause or accelerate atherosclerosis , include many pathogens but the present study focused on Helicobacter pylori, hepatitis B virus surface antigen and C. In order to evaluate the possible association between H. pylori, HBV, and HCV infections and the risk of