In this research the natural frequency of a cracked simple supported beam (the crack is in many places and in different depths) is investigated analytically, experimentally and numerically by ANSYS program, and the results are compared. The beam is made of iron with dimensions of L*W*H= (0.84*0.02* 0.02m), and density = 7680kg/m3, E=200Gpa. A comparison made between analytical results from ANSYS with experimental results, where the biggest error percentage is about (7.2 %) in crack position (42 cm) and (6 mm) depth. Between Rayleigh method with experimental results the biggest error percentage is about (6.4 %) for the same crack position and depth. From the error percentages it could be concluded that the Rayleigh method gives close results to experimental than ANSYS. Also it is found that the frequency of beam when the crack is in the middle position is less than the frequency with crack near the end position.
أولاً: مشكلة البحث:
على الرغم من أن كل شخص هو كائن متفرد بحد ذاته ، إلا أن هناك تشابهات مشتركة بين كثير من الناس ، وتشكل هذه التشابهات أنماطآ شخصية يهدف علم النفس إلى دراستها وفهمها.
وقد حاول علماء النفس والمنظرون في مجال الشخصية بناء أنظمة نظرية لتغطية التباين الواسع بين الأفراد في السلوك ضمن المواقف المختلفة. وهدفت جهودهم إلى فهم الدافعية البشرية ، والسلوك عن طريق عملية النمو
... Show MoreIt is from the greatness of God Almighty and from him that he facilitated for me to delve into the immersion of the hadith of the Prophet in my doctoral dissertation, then I found it a fertile ground for the cultivation of scientific results.
Through this work, I chose the topic (Replies of Al-Aini to Ibn Malik in his book Umdat Al-Qari Sharh Sahih Al-Bukhari) because of its scientific impact, as such topics inspire in the soul of the follower and the student a lot of contemplation and great care to understand the texts and then come up with a result that is almost close. It is correct, and my current situation in this research is the condition of many scholars, not without errors and omissions. Whatever was correct is by the grace of
Software testing is a vital part of the software development life cycle. In many cases, the system under test has more than one input making the testing efforts for every exhaustive combination impossible (i.e. the time of execution of the test case can be outrageously long). Combinatorial testing offers an alternative to exhaustive testing via considering the interaction of input values for every t-way combination between parameters. Combinatorial testing can be divided into three types which are uniform strength interaction, variable strength interaction and input-output based relation (IOR). IOR combinatorial testing only tests for the important combinations selected by the tester. Most of the researches in combinatorial testing appli
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MO Khudhair, 2020
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
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During the period 1970-2006 the Marshes-land region was exposed to several change into many sides of vanishing steeling and growth as follow :
1- Drying this region after 1991,and re-flooded again during 2003. Many other large Marsh-land, like al-Hawaisa was dried by cutting off inlet-water fed from Iran sources .As asqunance there are transferred to different kinds of swamps ,followed by major change in the structure of the region as the rural settlement concerned. Rural settlement in this area starts new push of migration. The research did not take that in consideration in this thesis because some others took it in details in some thesis and researches. The situation of Marsh-land is getting anew face after those major changes which
Background: The grading systems of salivary mucoepidermoid carcinoma depend on different histologic and morphologic features. The aim of this study was to compare between Auclair and Brandwein systems according to their histologic criteria, and the type of cell predominant. Materials and Methods: Twenty-one case included hematoxylin-eosin (H&E) stained tissue slides that were diagnosed as MEC, originally categorized into low and high grade type regardless of the grading system, have meticulously undergone histopathologic review. The sample was graded according to criteria owing to Auclair and Brandwein methods. The predominant type of cells was determined by microscopic examination according to grade of tumor. Results: Regarding the
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Background: Loss of tooth structure may be due to tooth to tooth contact and presence of abrasive components in the work environment. The aim of study was planned to evaluate the occurrence of dental attrition among Cement factory workers. Material and Method: The Sample included all workers chronically exposed to cement dust in the EL-Kubaisa cement factory (95 workers). A comparative group of workers (97) were non-exposed to cement dust was selected. All workers were males in gender with age range (25-55) years. The assessment of tooth wear was based on the criteria of smith and knight, 1984. Results: The maximum tooth wear score for exposed workers was 84.2% while non exposed workers was 38.1%,with statistical differences between two g
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