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.
The Arab woman expressed the life of oppression that she suffers from in her masculine environment, as she expressed her linguistic abilities with eloquence and intelligence, as she did not neglect philosophy, wisdom, and exhortation
Bohemia AL-Kharab for Salah Salah Which contain 477Paper deal With History of Nathion This Novel Has a different styl from another IraQis Novels, this Novel has no conversation this is the basic reason Which hav this research .
The novel have 3 versions , the first one deal with explain the text in different ways , the second contains the realation ship between the text and the reader .
Which appear very clear in novel from up to down , whil the third one and the last explaine
The hermonologiq
The time bylose the relation in the novel.
The last thing is the conclusion which has the simple things conclude by the researcher from several readings to the novel
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Abstract
This study dealt with " The Strategic analysis of Operating Income". The study Concerned with two main variables, they are: Strategic analysis and operating income and used one of the total strategic analysis tools, it is "resources analysis method" through analysing the change in operating income in the years that taken in comparing in three components: growth, price recovery and productivity.
To achieve the goal of the research, the study depended upon a hypothesis, "The strategic analysis of operating income leads to supply the appropriate information for the management to make sure of executing its definite strategies".
There is agroup o
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اهتمام العلماء العرب بالحروف مبينين معانيه موضحين مقاصده
The oil sector in Iraq suffered from several difficulties led to the decline and reduction of oil production and the deterioration of refineries and transport pipeline status in addition to the weakness of the technology side and the prevalence of financial and administrative corruption besides the high costs of rehabilitation of the oil sector and also administrative and institutional problems still ongoing.
In spite of Iraq's possession of vast oil wealth allows him to play an important role in the international energy market، he is still under the level. The production of oil doesn'<
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يتناول البحث مدى المسؤولية المدنية المترتبة على وزارة الداخلية عن اعمال منتسبيها
The legal text in the language of civil law, constitutional law, language of judges, and legal profession is concerned with a legal language and words that are coherently significant