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.
يتناول هذا البحث موضوع مهم في تاريخ العراق في العهد الملكي يتمثل في الانقلاب العسكري الذي قام به عدد من قادة الجيش العراقي بقيادة الفريق بكر صدقي رئيس أركان الجيش العراقي سنة 1936م وتم تشكيل حكومة من الانقلابيين استمرت حوالي تسعة أشهر وكتب عنها الكثير بعض هذه الكتابات كانت مع الانقلاب وبعضها كانت ضده وجاء هذا البحث ليسلط الضوء على ألصوره الذهنية التي حاولت ان ترسمها الصحف العراقية في حينها وتم دراسة الموضوعات
... Show MoreGompharena globosa L., Irisene herbistii Hook. ex Lindl. The results of this study showed that the anatomical characters of the stems epidermis and the indumentum covering different parts of the plant have an important anatomical characters such as the cell wall shape of ordinary epidermal cells also the shape and type of stomata, their presence in some taxa and abscent in others. The hairs also differentiated by their shapes and them types, either they glandular or eglandular also they are different in distribution between the different taxa or in the some taxon.
Parmi les oeuvres d'Albert Camus, qui s'éloignent un peu de sa
tendance générale qui traite les thèmes de l'absurde ,du néant et de la
question de la mort , on trouve son recueil "l'Exil et le Royaume" 1957
qui contient six nouvelles qui sont d'une invention moins épouvantable
(le Renégat , la Femme adultère , les Muets , le Pierre qui pousse , l'Hôte
et Jonas). Ces nouvelles , à l'exception du "Renégat" , ne provoquent pas
les questions philosophiques et dialectiques qui dominent la plupart des
oeuvres d'Albert Camus , Mais ces nouvelles traitent tout simplement la
question d'homme exilé dans son existence et sa recherche perpétuelle
de son royaume.
المستخلص تهدؾ الدراسة الى ل اٌس مدى التطب كٌ والتبن للم اٌدة ال مٌظة ف المنظمات العامة ولد اشتمت مشكلة الدراسة النظر ةٌ من وجود فجوه معرف ةٌ وذلن لملة الدراسات والبحوث الت تناولت متؽ رٌ الدراسة بأبعاده )الرؤ ةٌ المح طٌ ةٌ, التمك نٌ, الشبكات ب نٌ اعضاء الفر قٌ, الترك زٌ, الم لٌ للتعامل مع حالات عدم التأكد( اعتمدت الدراسة منهج دراسة الحالة عن طر كٌ استعمال استمارة الفحص ف المنظمة الت تم اخت اٌرها دائرة العمل والتدر ب
... Show MoreAbstract
This research was conducted to test the hypothesis (There is no significant moderating effect for Dramaturgy on the relationship between impression management strategies and PTSD), (45) employees in Iraqi drilling company (Basra province) were selected as a sample. Findings showed that the percentage (0.91%) of the employees who are exposed to accidents as a result of work suffer from post traumatic stress disorder, which negatively affects their organizational behavior, thereby, reducing future performance, findings also showed that the employment of impression management strategies will assist management to address PTSD among employees wh
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The purpose of this research is to analyze the relationship between the emotional intelligence and the leadership personality of the managers . the research was tested at the college of administration and economics – university of Baghdad through applying it on a sample of (67) members and units of the college. a questionnaire was used as a major tool for collecting data and information . for the purpose of researching to conclusion, the research aimed to test two main hypotheses related to the correlation coefficient and the effect correlation between the two main variable of the research, some statistical techniques such as (the mean, student deviation, percentages, correlation coefficient spearman, simple regression) were us
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This research work dealt with the problem of layout the production line of engine of fan roof at the General Company for Electrical Industries (GCEI). It was observed that the assembly line of engine was unstable and subject to severe fluctuations. In addition the execution of tasks at some stations was observed to be very fast while at other stations was slow. This phenomenon resulted into bottlenecks between workstations, idle time, and work in process. The system design was used to assign tasks to work stations according to different heuristics (Ranked Positional weight techniques, longest Task Time, Most following tasks, Shortest tasks time, Least number of following task).
The study revealed that th
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Mottos Of Opposition Movements In iraq during the umayyad period and their religious and political indications - al shia and al khawarij
The Sebkha is considered the evaporative geomorphological features, where climate plays an active role. It forms part of the surface features in Mesopotamia plain of Iraqi, which is the most fertile lands, and because of complimentary natural and human factors turned most of the arable land to the territory of Sebkha lands. The use satellite image (Raw Data), Landsat 30M Mss for the year 1976 Landsat 7 ETM, and the Landsat 8 for year 2013 (LDCM) for the summer Landsat Data Continuity Mission and perform geometric correction, enhancements, and Subset image And a visual analysis Space visuals based on the analysis of spectral fingerprints earth's This study has shown that the best in the discrimination of Sebkha Remote sensing techniques a
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