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 widespread of internet allover the world, in addition to the increasing of the huge number of users that they exchanged important information over it highlights the need for a new methods to protect these important information from intruders' corruption or modification. This paper suggests a new method that ensures that the texts of a given document cannot be modified by the intruders. This method mainly consists of mixture of three steps. The first step which barrows some concepts of "Quran" security system to detect some type of change(s) occur in a given text. Where a key of each paragraph in the text is extracted from a group of letters in that paragraph which occur as multiply of a given prime number. This step cannot detect the ch
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A general and accurate morphological study was carried out for the species Calotropis procera which belongs to the family Asclepiadaceae. The research included the phenotypic characteristics of the root, stem and leaves the leaves were studied morphologically and anatomically, Flowers, fruits and seeds, as well as the geographical distribution of the genus were studied also. In general, there are no previous taxonomic study of this genus under consideration, according to the available sources and it is the first one has been done in Iraq, perhaps Because of its low prevalence previously, where it was recently noticed its spread in last two to three years ago. Keywords: Apocynaceae, Apple Sodom, Poisonous Plant, Anatomy
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I have studied the relationship between blood groups in humans and disease Cutaneous injury for the first time in Iraq study showed the presence of a significant statistical relationship between them leather Bmsoy in hospitals in Baghdad and its suburbs
This paper is devoted to introduce weak and strong forms of fibrewise fuzzy ω-topological spaces, namely the fibrewise fuzzy -ω-topological spaces, weakly fibrewise fuzzy -ω-topological spaces and strongly fibrewise fuzzy -ω- topological spaces. Also, Several characterizations and properties of this class are also given as well. Finally, we focused on studying the relationship between weakly fibrewise fuzzy -ω-topological spaces and strongly fibrewise fuzzy -ω-topological spaces.
Research has included preparation of three of n Vthal acids Amec Bmentoj high of interaction vehicles Ortometta and bar aminophenol with phthalic anhydride was withdrawn water and ring closure of acids Alvthal AMEC prepared