This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.
The scholars differed very much in determining the grammatical doctrine of Ibn Qaysan. It was said that he confused between the two sects and took the two groups(1) and that he took from Abu Abbas the fox and Abu al-Abbas almabrd(2).He was descended from the two sheikhs almbrad and fox(3), This research to find out his grammatical opinions in the tools and grammatical words that appeared in the Book of Resonance of Multiplication to the many reported by Ibn Hayyan in it, he has seen the books of Ibn Kisan did not reach us.
The collection of these opinions and analysis is important for the scholars. Because the books of Ibn Kaysan specialized in grammar have lost their most important, the books that are similar to the book of Ibn al-Ha
Interested in many scholars and reseachers the subject of the media and means varied his roleinfluential in the definition of the public of issues and political, cultural, social and because of its spread wide and ability to address the people of all levels effect them in the formation consciousness of those issues and types of this awareness is an awareness of the tax, contribute to media formation consciousness tax through the definition of people what tax and importance of the role of its revenues to supplement the state budget by posting tax laws and regulations of applied and all what respect process account tax, to be in charge of the tax familiar enough about this, which avoid being cheated taxmisleading when rev
... Show MoreThe study aims to identify the degree of Tabuk University practices to raise the intellectual awareness of students through scientific research, as well as to identify the degree of Tabuk University practicing to raise the intellectual awareness through the educational process (faculty member – activities). The study also seeks to identify the degree of Tabuk University practicing to raise the intellectual awareness of students through community service and university media. The study is descriptive in nature that employed the questionnaire as a tool in collecting data. Total of (540) students were chosen randomly from different colleges at universities of Tabuk to form the study sample. The results showed that faculty member has pract
... Show MoreThis research concerns the fact of the school garden and how can we tackle this issue. The research starts with a question forwarded to those who are interested in the ministry of education matters; the question is that how is the extent of interest in the school garden project? And how it is activated in the Iraqi Educational Institution program? In addition, the analysis reveals the importance of the school garden since we, as teachers and students, suffer from seeing the view of the trashes, the wastes of school furniture, the stinking water and the weeds and how it is accumulated in the back yard of the school. To add fuel to the fire, the increase in number of the students; year after year. This increase leads to adding more classes
... Show MoreThe aim of the research is to demonstrate the importance of leadership empowerment in its dimensions (knowledge, participation in decision-making, incentives, trust between the leader and subordinate, delegation of authority and communication) and its impact on enhancing the effectiveness of the company in its dimensions Represented by (achievement of objectives, quality of insurance service, adaptation to work environment and job satisfaction), by adopting the questionnaire as a main tool in collecting data from officials in the National Insurance Company, numbering (56) surveyed in job sites (section manager, division official and unit official) Their answers were analyzed using the SPSS statistical program in calculating the a
... Show MoreStarting with a problem of the weakness of accounting disclosure in some companies administration when preparing and presenting the financial reports which are submitted to the Tax authority. This problem impacts on Tax authority performance (The effect on the quality of the performance of the tax authority), because of the lack of conviction for the information contained in those reports, and the failure to achieve accurate results in tax authority performance that leads to a negative impact on determining taxable income and affect tax revenue, as well as negative impact on determining taxable income and affect tax revenue, as well as negati
... Show MoreThe study focuses on the problem that Iraq is approaching an increasing rate of literacy;the available data refers to a rate of (18% -19%). In addition to the fact that the generalcurrent role of the programs directed to literacy is not actually effective enough to limit the expansion of this rate.
The importance of this study highlights the fact that the Iraqi universities are an important tributary among the tributaries of human development, especially in spreading the education of the voluntary work in literacy field and confirming the connection between the students and their society and their role in solving one of the prominent challenges that face the development, i.e., literacy.
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... Show MoreThe worsening of environmental problems has led to them being addressed by many entities, the most important of which are the top regulators. Federal Board of supreme audit Office is one of the most important regulators in Iraq. The problem of the research was the fundamental question of the extent to which the Federal Financial Supervisory Office was committed to implementing and exercising environmental control over the audited ones. The refore, the research was based on the main objective of questioning the role of the Federal Financial Supervisory Office in the exercise of environmental control and the compliance of those under its control, by identifying the antosai standards for environmental control, particularly the stand
... Show MoreAbstract
There has been a heated controversy over the role the financial policy plays and how sufficient it is in affording the financial burden. This burden is known as the operational current expenses which the governments of various countries mainly afford, despite the discrepancy in the government’s economic policy. After the deterioration and deficit in the state budget in all countries nowadays, it was necessary to find an appropri
... Show MoreThe study aimed to evaluate the distance learning experience in light of the spread of the Corona pandemic - Covid19 - from the teachers' point of view in Islamic Science Institutes in the Sultanate of Oman, which was applied during the second semester of the 2019/2020 academic year. The study sample consisted of (77) teachers from The Islamic Science Institutes of The Sultan Qaboos Higher Center for Culture and Science. The researchers prepared a questionnaire to evaluate the reality of the experience. The study results revealed, the followings: The Department of Educational Affairs and Training at The Sultan Qaboos Higher Center for Culture and Science was able to a moderate degree in the rapid transition to a distance learning s
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