This article deals with the impact of including transverse ribs within the absorber tube of the concentrated linear Fresnel collector (CLFRC) system with a secondary compound parabolic collector (CPC) on thermal and flow performance coefficients. The enhancement rates of heat transfer due to varying governing parameters were compared and analyzed parametrically at Reynolds numbers in the range 5,000–13,000, employing water as the heat transfer fluid. Simulations were performed to solve the governing equations using the finite volume method (FVM) under various boundary conditions. For all Reynolds numbers, the average Nusselt number in the circular tube in the CLFRC system with ribs was found to be larger than that of the plain absorber tube. Also, the inclusion of transverse ribs inside the absorber tube increases the average Nusselt number by approximately 115% at Re = 5,000 and 175% at Re = 13,000. For all Reynolds numbers, the skin friction coefficient of the circular tube with ribs in the CLFRC system is larger than that of the plain absorber tube. The coefficient of surface friction reduces as the Reynolds number increases. The performance assessment criterion was found to vary between 1.8 and 1.9 as the Reynolds number increases.
Comparative taxonomic study has been compeleted for the species of the. genus Centaurium Hill. of Iraq. So the morphological characters were studied comparatively for the first time form Iraqi materials. Stems, leaves ,infloresences and reproductive organs characters were a good taxonomic importance. Geographical distrtribution has been done for the species of the genus in addition to the environment information. The results were presented with schedules, tables, maps and micrographs. Taxonomic key for the species separation was also presented.
The ritual is a Sunnah between the two prostrations, not as some of the worshipers do, where he made it in the last tashahhud when the tasleematin, and it may be in the last tashahhud.
The assumption is Sunnah and most of the scholars say that in the middle tashahhud session as we have shown through research.
The Turks are Sunnah as well, and it is at the end of the prayer, whether it is double, triple or quadruple, whether it is naval or NAFTA, whether it is urban or travel, which is the view of most scholars from the three imams and others.
If we say weighting, say the audience of the three imams (Malik, Shafi'i, and Ahmad) is the most correct, and it is also the son of values, and if we say the choice is as Ibn Rushd said: by
The linguistic researcher reads a systematic crisis, idiomatic problems within the linguistic term coming to the Arab culture. Where most of them return back to problems of receiving these sciences which are represented by phenomena like the multiplicity linguistic term, disturbance translated idiomatic concept and its duality.
Aims of the research :
1-Initializing new textbooks to form linguistic project and Arabic linguistic theory.
2-Determination adjusted knowledge, concepts of Arabian heritage linguistics subject
3-Observation the causes of disturbance crisis of linguistic term and its relation to
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Westernization is a term not familiar to our scholars at the beginning of the emergence of translation from Western literature, sciences and arts in its detailed form now.
Westernization was not an issue that those Greeks, Persians, Romans, Indians and others worked on translating those sciences and cultures. Rather, it was a process of transferring a new philosophy and logic that had not been previously seen by the Arabs, so they were affected by it in a strange way, to the point of fascination by some of them. For this reason, this research came to clarify these issues and address them within the scientific methodology.
The elements of theater formation that fall within the spatial experience of the scenography of the show, which the directors work in in the imaginary theater, are important and have an aesthetic, intellectual and cognitive dimension, working to highlight reality in an aesthetic image surrounding space and space. And its relationship to the distinct, multiple and variable spaces above the stage, to produce theatrical signals and endless meanings through the possibility of infinite reconfiguration of the theater's space and its public and private space through the distribution of a group of blocks within the scenic image.
I dealt with in the first chapter (the methodological framework), which includes the research problem identified
Discotic liquid crystal compounds were synthesized and characterized. Liquid crystalline texture of these compounds was investigated by polarized optical microscopy (POM). The Hartree-Fock approximation (HF) was used to calculate theoretical molecular parameters for synthesized compounds such as optimization, hardness, EHOMO, ELUMO, and energy gap using the Gaussian 09W program.
Recent advances in wireless communication systems have made use of OFDM technique to achieve high data rate transmission. The sensitivity to frequency offset between the carrier frequencies of the transmitter and the receiver is one of the major problems in OFDM systems. This frequency offset introduces inter-carrier interference in the OFDM symbol and then the BER performance reduced. In this paper a Multi-Orthogonal-Band MOB-OFDM system based on the Discrete Hartley Transform (DHT) is proposed to improve the BER performance. The OFDM spectrum is divided into equal sub-bands and the data is divided between these bands to form a local OFDM symbol in each sub-band using DHT. The global OFDM symbol is formed from all sub-bands together using
... Show MoreAs the child is growing up, he goes through different phases which will be accompanied by physical and psychological changes. These changes set the basis for processes of designing and making children's clothes which in turn give its required benefits and meet the physiological, psychological and community needs. That will help provide the child with healthy physical and psychological growth.
The aim of this research is to recognize the decoration of clothes by colors and drawings and its role in clothes' richness and children's education. The research limits are objective, The limits are for female (3-5) years old. The research was done in teaching kindergarten in the college of education for women in 2016. The researchers found many