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 main purpose of the research is to diagnose the importance of the role that strategic memory plays with its three variables (content, structure, and processes) in helping the human resource department to use the COSO model with its five components (culture and governance, strategy and objectives, performance, communications and information, and feedback) in auditing activities and tasks Her own. As the research problem emphasized the existence of a lack of cognitive perception, of the importance of strategic memory, and the investment of its components in the rationalization of the application of the COSO model. and therefore it can be emphasized that the importance of the research is to provide treatments for problems relate
... Show MoreBackground: five clinical phases were described in patients with chronic (HBV) infection: HBeAg- positive HBV infection, HBeAg- positive chronic HB, HBeAg negative HBV infection, HBeAg-negative CHB and occult HBV infection. Aim: This study aimed to determine the incidence of the unclassified phase (gray zone) in chronic hepatitis B patients and its significant in the clinical practice. Patients and methods: The study was conducted retrospectively on 109 patients' who have HBsAg positive for more than 6 months. The data recorded include; HbeAg and anti-HBe Ab, ultrasound of the abdomen, HBV DNA load and alanine aminotransferase (ALT), accordingly; we classify the patients to known clinical phases. Patients who were unfit one of these phases
... Show MoreUniversity libraries seek to evaluate their performance in order to correct their path and adjust it in the right direction. Therefore, they use (performance indicators), which are a tool used by institutions to evaluate the weaknesses and strengths in their work and the reasons for failure to achieve some goals sometimes. They convert (goals, procedures and actions) into a formula that can be measured mathematically, which contributes to the library determining the gap between its current performance and what those libraries are supposed to be on, clarifying the path that the library is following, controlling the risks that may befall it, and thus enhancing the process of continuous improvement to avoid areas of failure and weakness becaus
... Show MoreThe energy aimed at examining the mode of energy drinks consumption among athletes in
Baghdad and assessing their drinks were spread greatly among the athletes and students. This
study impression toward such drinks. The study sample comprised of 102 mal athletes aged
between 19-27 years and selected randomly .The obtained results showed that football was
most practiced among the test samples at 40.54% based on twice daily .The athletes
consumed one can each day at 41.18% .As the data on energy drinks was supplied from
friends .The prefared period for drinking was before or during exercise .The athletes thought
that there products can provide energy ,vitamins ,tell ale materials ,does not affect
appetite.The most f
Begging is an ancient social phenomenon since the Man's creation. It was simple at its beginning to get a living and the family needed, but presently, this simple social phenomenon converted to a big phenomenon which controlled by competent groups away from the values and principles. Their doings are far from humanity representing by the cutting of a hand or a foot and facial distortion or removed eye as a way of attracting people's emotions to get material and incorporeal helps; these doings became a trade which is exchanged by slave traders. Furthermore, different illegal and greedy methods were followed as a way of blackmailing others; contrariwise other cases of begging are doing by a people who real poor and needy. In this case, the
... Show MoreThe art of postmodernism has undergone a number of changes in the course of art and art schools, as art has left the traditional means and paved the way for this artistic transformation to change the materials, techniques, methods and visions as a result of the changes that occurred in the thought and this change played an important role in the artist's vision, To demolish and destroy all of the above and to reconsider the formal systems and intellectual contexts and expressive modes, so it is necessary for the whole art to keep up with the variables of the era and its elements. The current research aims to: "Detect the transformations of form in postmodern art in the projects of students of the Department of Art Education".
Sinc
... Show MoreResearchers often equate database accounting models in general and the Resources-Events-Agents (REA) accounting model in particular with events accounting as proposed by Sorter (1969). In fact, REA accounting, database accounting, and events accounting are very different. Because REA accounting has become a popular topic in AIS research, it is important to agree on exactly what is meant by certain ideas, both in concept and in historical origin. This article clarifies the analyzing framework of REA accounting model and highlights the differences between the terms events accounting, database accounting, semantically-modeled accounting, and REA accounting. It als
... Show MoreThe current research presents a study of the sculptural body in the space of the theatrical show through reviewing most of the ideas, propositions and workings presented by philosophers and directors within the space of the show, that there were various experiences of employing those spatial formations through the mediator (the space) based on sculpturing the body in achieving those formations, which contributed in building a symbolic picture of various structural connotations. That was formulated through the research chapters, which include the first chapter (the methodological framework) which consists of two sections. The first section (the duality of space formation and imaginations). The second section (sculptural body sequences in
... Show MoreThe technology and modern social communication medias have contributed to changing many of our concepts about education to a large extent; these technological advancements have created new challenges for the Instructor of course, but on the other hand it did provided him with expressive media, models and strategies that the old methods cannot fulfill, including the flipped classroom strategy, which is one of the modern technical solutions and in it's optimal use it can correct the weakness of the traditional education and can develop the communication skills as a whole among the students, in order to create a positive, active and interactive student.
The current research contained - four chapters: the first one included the methodolog
The objective of this study is to determine the sources of growth of the cement industry in Iraq for the period 1990-2014 and to indicate the nature of the technological progress used in it. To achieve this objective we have built an econometric model, by adapting the production function constant elasticity for substitution, using multiple regression, and enforcement, SPSS program, and using the ordinary least squares method (OLS). The results showed that quantitative factors (labour and capital) are the main sources of growth the cement industry in Iraq, and the qualitative factors (technological progress) did not contribute effectively to achieve this growth. And that the production techniques adopted in the cement industry in
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