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.
Turkey Consider Tigris and Euphrates rivers as a national rivers, and not an a International rivers, so that . It insists on its absolute sovereignty on that resources. The block ( levee ) which Turkey established should not create International problems.
The All International agreements and laws in this sect warrant the rights of all the states that located in river stream to use it without any consider to the regional absolute right.
During the 1980s, Turkey construct water projects, started with GAP, project which is one of the greatest project in the world, in spite of the plane of construct of the keep an levee on the Euphrates was pre of that project. The
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Karagöz , tarihin derinliklerinden düşünülmüş bir hayal oyunu’dur . Beyazperde üzerine , birtakım tasvirlerin gölgelerini yansıtmak suretiyle gösterilentemaşa çeşididir. Meddahlık ile orta oyunu’na yakınlığı ve aşağı yukarı aynıteatral unsurları , komik temaları kullanması dolayısı ile karagöz’de sözlü tiyatrogeleneklerisayabiliriz . Nitekim bu hayal oyunu’nun perde arkasına yerleşerekhüner gösteren bir tek aktörüvardır . Bu aktörün oyun için kullandığı malzemeperde , şema (mum) ve tasvirler’dir. Altı yüzyıldır canlı kalan karagöz , dünyanın eneski en zengin ve en güzel halktiyatrolarındandır. Türk toplumunun yüz
... Show MoreOver the course of two centuries, Portugal emerged as one of the most powerful European empires, with colonies stretching from Asia and Africa to Brazil. A significant factor in this expansion was the role of winds, which carried one of Cabral’s ships westward, landing unexpectedly on unknown shores—the Brazilian coasts. These territories later became some of Portugal’s richest and most important colonies. Therefore, the study begins in the 16th century and concludes at the end of the 17th century. The study was divided into four sections. The first section addressed Portugal's discovery 0022 of Brazil and its naming before it gained economic importance. The second section discussed the Portuguese occupation of Brazil in 1530 and its
... Show MoreThis article suggests and explores a three-species food chain model that includes fear effects, refuges depending on predators, and cannibalism at the second level. The Holling type II functional response determines food consumption between stages of the food chain. This study examined the long-term behavior and impacts of the suggested model's essential elements. The model's solution properties were studied. The existence and stability of every probable equilibrium point were examined. The persistence needs of the system have been determined. It was discovered what conditions could lead to local bifurcation at equilibrium points. Appropriate Lyapunov functions are utilized to investigate the overall dynamics of the system. To support the a
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The nature of the dark sector of the Universe remains one of the outstanding problems in modern cosmology, with the search for new observational probes guiding the development of the next generation of observational facilities. Clues come from tension between the predictions from Λ cold dark matter (ΛCDM) and observations of gravitationally lensed galaxies. Previous studies showed that galaxy clusters in the ΛCDM are not strong enough to reproduce the observed number of lensed arcs. This work aims to constrain the warm dark matter (WDM) cosmologies by means of the lensing efficiency of galaxy clusters drawn from these alternative models. The lensing characteristics of two samples of simulated clusters in the Λ warm dark matter and ΛCDM
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Many cinematic adaptations were produced for the Grimms’ “Little Snow-White” (1812) including Mirror Mirror movie (2012), the contemporary version adapted by Taresm Singh. Singh’s version was able to depict the modern reality of women and went against patriarchy by embracing feminist ideologies of the fourth-wave feminism. Therefore, he challenged the ideologies of the mainstream cinema dominated by the patriarchal élite’s capitalist mode of production that still adhere to the stereotyped patriarchal image of women’s ‘victimization,’ ‘objectification’ and ‘marginalization,’ which did not represent women’s modern reality anymore. This paper, however, is a qualitative study aimed to prove that the femini
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The paper has been summarized into the following:
Chapter one: the researcher deals with the problem of the paper, the most important points and the terminology. Chapter two: the researcher deals Surat Luqman from the Aya 12-19 , (the demonstration, the explanations, the values ). In chapter three the researcher deals with Surat AL-Hujurat from Aya 6-12, (the demonstration, the explanations, the values ). Chapter four include (the educational properties for individual and society, the educational applications, and the most important indicators in the texts). Chapter five include the results , the conclusions and the recommendations. One of the basic results that the Quran is a complete educational curriculum, and the texts of Surat Lu
Receipt date:9/1/2020 accepted date:11/24/2020 Publication date:12/31/2021
This work is licensed under a Creative Commons Attribution 4.0 International License.
the Nile River and the Renaissance Dam is one of the most prominent factors that had an important role in the nature of relations between Egypt - Ethiopia, as they contributed to building a relationship that has common characteristics through the nature of the i
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The research aims to explain the References of receiving the explicit and implicit knowledge mentioned in the Noble Qur'an. The two researchers adopted the documentary and inductive approach to study the topic. Among the conclusions of the research: The Noble Qur'an dealt with many terms and concepts that refer to the References of making explicit knowledge available, including books, which were represented by the divine books (the Qur'an, the Torah, the Zabur and the Gospel) and their concepts (the book, the Qur'an, the guidance, the remembrance, the revelation, the light, the newspapers, the plates). He dealt with many concepts that refer to the References of providing tacit knowledge, which was represented by the communication between tw
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