The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
This research addresses: Sharh Usul Al-Bazdawi "Explanation of the Fundamentals for Al-Bazdawi", by studying and investigating, from the beginning of prohibition chapter to its end. The researcher conducted a study about this book stating its significance and introducing the compiler and the commentator. The researcher as well mentioned that the prohibition has a special formula and requires repetition, and he went on explaining that prohibition according to Hanafis does not require absolute corruption of the prohibited matter unless based on an evidence, and that what is condemned as wrong act for itself is considered void and what is condemned as wrong act for external reasons is considered corrupt accor
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The study aims at diagnosing the importance of environmental analysis (external, industrial and internal) in the organization's strategy for the development of public organizations. The theoretical problem derived from the existence of a knowledge gap for studies and research that dealt with the variables of the study. Three public organizations were selected as the study society (the Civil Defense Directorate, the Directorate of Nationality, Passports and Residency, the General Traffic Directorate). The sample of the study was a sample of (215) managers (managers, department managers, Analysis of the data and hypothesis testing using the appropriate statistical tools, Pearson, the simple and multiple regression coefficient to te
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ABSTRACT
Impkact of Knowledge sharing on organizational innovation Impriscal study in Arabic company .
of Knowledge Management is the main component Knowledge sharing system, it mean the exchange if Knowledge, ideas, and good practice with another individual . Knowledge sharing between persons, then its values can growth .
It is vry important because it can provide us with the contention between virus peoples . the interaction among the people can pass all kind of Knowledge among them. the connection and interaction and interaction enabl
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This research set to indicate the role of the opportunity cost in the overall economic development (human and social development) by selecting the most appropriate alternative for the growth of the country in exchange for sacrificing profit limits to achieve this growth and development of the country, especially in the present circumstances of the country and after studying the reality of the economic case for him, as the problem lies with don't selecting the best alternative that enhances the gross domestic product, which extends to promote overall economic development and revive the industrial and agricultural sectors, productivity is more like Impotent, versus sacrifice alternative consumption may bring more financially lucrative than
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Improvisation is that spontaneous automatic achievement which is formed by a new cognition that is not based on something prior to it or a previous cognition. It is instantaneous. Whereas in art, improvisation also inters in all types of applied and performance arts as a foundation for launching and initiating it in music, painting, cinema, television and theater. In order to study the improvisation of the actor, the researcher put forward a theoretical study that included two sections. The first section is (the improvisation concept) and the second section is (improvisation in the show). The researcher, in the research procedures, took an intentional sample that was represented by the theatrical show (Rehearsal in Hell Play) and after t
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In order to improve the effectiveness, increase the life cycle, and avoid the blade structural failure of wind turbines, the blades need to be perfectly designed. Knowing the flow angle and the geometric characteristics of the blade is necessary to calculate the values of the induction factors (axial and tangential), which are the basis of the Blade Element Momentum theory (BEM). The aforementioned equations form an implicit and nonlinear system. Consequently, a straightforward iterative solution process can be used to solve this problem. A theoretical study of the aerodynamic performance of a horizontal-axis wind turbine blade was introduced using the BEM. The main objective of the current work is to examine the wind turbine blade’s perf
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This research aims to demonstrate the nature and concept of the Corona pandemic, its implications for the global economy, and the management and performance of companies in particular. Additionally, the research intends to measure the impact of the Corona pandemic on companies' financial performance. Listed on the Iraqi Stock Exchange, which has finished compiling its year-end financial statements for 2019-2020. The investigation arrived at several findings, the most significant of which was that most businesses were not prepared for such a crisis technologically or to develop human resources to deal with this pandemic. In addition, most companies experienced a decrease in their financial performance as a direct result of the Corona pandemi
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The aim of the research is to shed light on the dimensions of the strategic lens and its impact on achieving the pioneer tax performance and represented by the dimensions (strategic direction, growth, pilot indicator, renewal and modernization, efficiency and effectiveness) in the General Tax Authority. The questionnaire was adopted as a tool to collect data and information from the adult sample They are (91) who are on the site (Assistant Director General, Head of Division, First Division Deputy, Second Division Deputy, Division Officer, Division Officer Associate) The statistical program (SPSS) has been used to calculate (the mean, the standard deviation, the correlation coefficient, the difference coefficient, the F test, the
... Show MoreFrom 1979 to 1999 several theatricl groups had produced (Mackbeth) by shakespear which were directed by different director and the role being played by different actors. So the questions are: How did those a Iraqi actors approach that character by their performance? Did they interpret the character Truelly as the poet wanted to be. The researcher aims to find out the true performance by the actor who impersonate (mackbeth) as a wicked personality, who had un rational ambition. The researcher also aims to expose the style of acting fallowed by the Iraqi actors in that play. In chapter of review of literature, The researcher discusses the weaning and procedure of the actor performance which include characterization and transformation. He a
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