A real method of predication brake pad wear ,could lead to substantiol economies of time and money. This paper describes how such a procedure has been used and gives the results to establish is reliability by comparing the predicted wear with that which actually occurs in an existing service. The experimental work was carried out on three different commercial samples ,tested under different operation conditions (speed,load,time...etc)using a test ring especially modified for this purpose. Abrasive wear is mainly studied , since it is the type of wear that takes place in such arrangements. Samples wear tested in presences of sand or mud between the mating surfaces under different operational conditions of speed, load and braking time .Mechanical properties of the pad material samples (hardness, young,s modulus and collapse load under pure bending condition )wear established . The thermal conductivity and surface roughness of the pad material wear also found in order to enable comparison between the surface condition before and after testing. Sliding velocity had a small effect on the wear rate but it had great effect on friction coefficient. Wear rate was affected mainly by the surface temperature which causing a reduction friction coefficient and increasing the wear rate. Surface roughness had almost no effect on the wear rate since it was proved experimentally ,that the surface becomes softer during operation .mechanical properties of the pad material had fluctuating effect on wear rate. The existence of solid particles between pad and disc increasing wear rate and friction coefficient while the mud caused a reduction in wear rate of the pad surface since it acts as a lubricant absorbing the surface heat generated during sliding the area of contact between pad and disc. wear rate obtained experimentally agreed fairly well that found from empirically obtained equations.
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The covid-19 global pandemic has influenced the day-to-day lives of people across the world. One consequence of this has been significant distortion to the subjective speed at which people feel like time is passing. To date, temporal distortions during covid-19 have mainly been studied in Europe. The current study therefore sought to explore experiences of the passage of time in Iraq. An online questionnaire was used to explore the passage of time during the day, week and the 11 months since the first period of covid-19 restrictions were imposed in Iraq. The questionnaire also measured affective and demographic factors, and task-load. The results showed that distortions to the passage of time were widespread in Iraq. Participants co
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The research, which was drawn from his doctoral thesis (People's Policy towards Vietnam 1949-1979), discussed the roots of the connections between the Chinese and Vietnamese communists since the 1920s, the presence of Ho Chi Minh and other Vietnamese communists in China, their influence by the revolutionary struggle of the Chinese Communist Party and their establishment of a group of The Vietnamese Revolutionary Societies and the Indo-Chinese Communist Party until the outbreak of the Vietnamese Revolution and their success in declaring the establishment of the Democratic Republic of Vietnam in 1946. Keywords: Ho Chi Minh, Chinese Communist Party, Indo-Chinese Communist Party, Democratic Republic of Vietnam, Chou En Lai.
Abstract
The current research aims to know the reality of the research's coefficients, to know correlation and effectiveness between the organizational Agility and high performance . The current research has been applied on the official banks , including a sample of senior administration members (120) ; besides , the research has used questionnaire that being considered as the main tool for gathering information and data . It includes 59 questions in addition to the personal interviews program as to support the questionnaire and to fulfill a great deal of reality. It has been anal
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The present study was conducted on the Iraqi Pin-tailed Sandgrouse (Pterocles alchata) to study the lung's morphological description and histological structure. This study was used 5 samples of adult male sandgrouse bird. The birds were dissected. The lungs were removed from the coelomic cavity, cleaned to remove impurities, and photographed to describe their morphological features. The samples were fixed using formalin (10%) solution for 36-48 hours and then preserved in alcohol (70%) to prepare the microscopic slides. The results showed that the lung of the Iraqi sandgrouse bird is red in color, has a trapezoidal shape and has three surfaces (costal, visceral, and vertebral). The costal surface shows ribs impressions that extend f
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The legal nature of the Build-Operate-Transfer-Ownership Contract (B.O.T) The Build, Operate, and Transfer of Ownership Contract (BOT) has emerged as the most successful and safest method for involving the private sector in public sector services. The major infrastructure projects that are built through the BOT contract are no longer financed by the state and its budget, but the private sector has played a major role in financing These projects, especially developing countries that need to establish infrastructure or modernize their existing infrastructure, especially in the areas of transport, communications, services, electricity, water ..... and other public utilities.
The cuneiform texts considered one of the most important resources which play an important role help us to know how was the economic , politic and religious manner and every thing have relation of the history of Mesopotamia which contain many of information that enrich our knowldgement every side of Mesopotamia civilization since using writing as away to register the science and human knowldgement . The city of Sippar (Abu –Habba ) was one of most important city of ancient Mesopotamia which mentioned as one of first five Mesopotamian cities found before floating and it exposed through excavating rich one of them tablet which some of it dated to old Babylon period . The king Ammi-Saduqa has a big share of tablet we study number of thi
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Abstract The dissemination of knowledge is no longer confined to schools and universities, not even books. For nearly two centuries, the media have become prominent in disseminating knowledge and culture, in its public and particularly political aspects. After the development of the media from newspapers and magazines to the visual media, their role has increased from the dissemination of abstract information and abstract knowledge towards the process of forming new knowledge through what it publishes and broadcasts from different programs such as drama, news and talk shows. The impact of the media has changed the overall community awareness. Half a century ago the media was not so powerful and widespread. The evolution of the 1990s made
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Judaism followed the approach of monotheism after God Almighty sent Moses (peace be upon him) to convey to them the messages of their Lord, so that they might be on a right guidance and path, but the people did not follow that path.” Love of matter and faith in what is witnessed, so they portrayed the Lord in several images in line with what their souls drew upon them.