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.
Contamination of the operating theatre is a major cause of nosocomial infection. This report aimed to show the types of microorganisms and their percentages cultivated from operating theatres of 16 health directorates of 14 Iraqi governorates (3 health directorates in Baghdad and 1 in each other 13 governorates) that was reported to the Pollution Control Section at Ministry of Health in Iraq from first of January to the end of June 2018. The data of all health directorates have included cultivation taken from governmental and private hospitals. Duhok, Erbil, Sulaymaniyah, and Nineveh were not involved in this report due to unavailability of their data during the above period. Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureu
... Show MoreThe Social life contain an important side from the inherited Civilization to any
nation, is distinguished by activity and zeal. The old Indian is characterized with
closed and solidify socilal systems. This state had its influences on the activities of the
social movment. It astonished the conquered mushins – Arab to the India from the end
of the first centuny A.H we tried to change it by good works and made them become
aware, so this made radical active in the social India in Islamic period which is form
humanbeing nobilitie and their active deal in the society.
The study of images in the cognitive field receives considerable attention by researchers, whether in the field of media and public relations or in other humanities. Due to the great importance in shaping trends of public opinion, especially trends that individuals and the behaviors of people, institutions or ideas are determined by forming images that they hold in their minds towards these persons or institutions. Modern enterprises have realized, whether they are governmental ministries and official departments or non-governmental organizations as civil society organizations, the importance of studying the dominant image in the minds of the masses and make decisions and draw plans to configure this image as these institutions wishes.&n
... Show MoreThe theater benefited from the concept of (hypertext) to create different virtual worlds. The four chapters of the research included the first (methodological framework), the second (theoretical framework) came in two sections (hypertext, its concepts and applications) and (hypertextual space in theatrical performance), and the investigations resulted in indicators, including:
1- Hypertext is interacting interactively, but it is organized by correlation as a basic feature that defines it with different manifestations.
2- The hypertext combines the word with other formative elements that reduce a set of tagged information (word, image, light, shadow, color, number).
In the third chapter (research procedures) (Lord play) was
دور اللوبي الصهيوني في صنع السياسة الأمريكية
The Semitic Languages have her its Articulatory That what we attend to discuss In this Research to Represent the Relation Between them and the Light Of Semitics a Comparative Studies where ever It's Exists The Semitic languages by comparing the words whish most Semitic languages share with each other. We call such Words the Semitic denominator. We have adopted a comparative framework in our Research, which is based on comparing an Arabic word with its Semitic counterpart in Order to identify the forms that control grammatical change in both language
... Show MoreDrama is one of the means of transmitting human experiences, as it presents within it the life ideas and visions of the spectator, who is subject to their influence on him, robbed of the will in front of its charm and various display arts, which invade him with its dimensions and affect his references, and this art form is based on stories revolving around personalities involved in events that have grown As a result of the struggle of two conflicting opponents, or two opposing forces or emotions generated as a result of a voluntary conflict, as this dramatic conflict represents the most important elements of those events, as it is embodied in an inevitable scene that emerges from other scenes, and this scene is sometimes subject to the
... Show MorePoor impurity in the right of the patient and the elderly
This research is concerned with the study of (the dialectic of the familiar and the unfamiliar in Islamic photography), and it consists of four chapters.
If you dealt with the problem of the research subject (the dialectic of the familiar and the unfamiliar in Islamic photography, as it appeared realistic, familiar forms and strange and strange unfamiliar forms represented in many of the main schools of Islamic photography that emerged in Iraq and Persia and then the Ottomans and the However, Islamic painting still retains those previously witnessed and unseen images, which pose themselves forcibly in the form of many questions that must be faced and studied by investigation, observation, extrapolation and conclusion through scientifi
The Sound of the letter (ق) in the Contemporary Arabic Dialects