The thermal and electrical performance of different designs of air based hybrid photovoltaic/thermal collectors is investigated experimentally and theoretically. The circulating air is used to cool PV panels and to collect the absorbed energy to improve their performance. Four different collectors have been designed, manufactured and instrumented namely; double PV panels without cooling (model I), single duct double pass collector (model II), double duct single pass (model III), and single duct single pass (model IV) . Each collector consists of: channel duct, glass cover, axial fan to circulate air and two PV panel in parallel connection. The temperature of the upper and lower surfaces of PV panels, air temperature, air flow rate, air pressure drop, wind speed, solar radiation and ambient temperature were measured. The power produced by solar cells is measured also. A theoretical model has been developed for the collector model IV based on energy balance principle. The prediction of the thermal and hydraulic performance was obtained for the fourth model of PV/T collector by developing a Matlab computer program to solve the numerical model. The experimental results show that the combined efficiency of model III is higher than that of models II and IV. The pressure drop of model III is less than that of models I and IV, by (43.67% and 49%). The average percentage error between the theoretical and experimental results was 9.67%.
In this paper we have dealt with the word " בַּיִת" in the Book of Joshua because it makes one of those that highly employed the word בַּיִת" " in the Old Testament. The Book of Joshua comes sixth in the order of tanakh wich was written by Joshua son of Noon in Palestine during the fifteenth century B.C. and it covers a three-decade era extending from the death of Moses til the death of Joshua son of Noon.
The word " בַּיִת " in this paper refers to the place, where expressions are made by a noun modified by a noun . The modifier is"" בַּיִת , and the modified is another noun. Herein, we
... Show MoreThe space constitutes a cornerstone of the creativity process since the emergence of arts and literature. Gaston Bachelard has a significant role in highlighting the importance of the place in his book entitled (Poetics of Space). Since then, the space, especially in the TV drama, is no longer a mere background indicating the location or the date of the event. Space inside these series has become an inseparable part of the artistic or dramatic fabric, that the visual scene started to formulate alongside the movement of the individuals in their language or accents that are specified inside the space as an incubator for the décor, clothes, makeup, accessories and lights in addition to the sound and musical effects. The lens angles
... Show MoreThe problem of the research represented by knowing the approaches which presented by knowing the design guides and the design styles which the imitation products enter upon it to be able to competitor the other original products .The research aim was to comparison the design approaches of the functional performance and the utilizations for the imitation and the original products , however the research limits contained study products samples of the kitchen electric equipments which available in local markets of Baghdad city for the period (2000 – 2013) .After the view of research back for the subject fundamental basics and investigating research sample to be complete to a group of results and conclusions and the most marked of her were
... Show MoreThe aim of this work is studying the binary system ??'??? Ni?)with two ratios (y=36,80) by using casting method for preparing the samples.Magnetic and Mechanical properties have been studidt different httrea^nttem^rature.All the alloys were found a ferromagnetic behavior and sensitive to the heat treatment. Best properties were found at the heat treatment 1100 C°.A significant different results were found above 1100C° for lower magnetic and mechanical values. This is possibly due to the change on the degree of magnetic moment orders, in which most of the moments are started to remove from coupled ferromagnetically.?
This study presents the effect of laser energy on burning loss of magnesium from the holes' drilled in aluminum alloy 5052. High energy free running pulsed Nd:Glass laser of 300 µs pulse duration has been used to perform the experiments. The laser energy was varied from 1.0 to 8.0 Joules, The drilling processes have been carried out under atmospheric pressure and vacuum inside a specially designed chamber. Microhardness of the blind drilled holes has been investigated .The results indicated that the magnesium loss could be manipulated by adjusting the focusing conditions of the laser beam. Almost, the obtained holes were free of cracks with low taper and low sputter deposition. .The holes performed under atmospheric conditions have high
... Show MoreThe article attempts to provide the theoretical fundamentals for the semiotic component of lacunae in a language. The definitions of the following notions have been represented: 1) lacunarity as a complex phenomenon that works in the modes of language, speech and speech behaviour; 2) lacuna as a gap, an empty space, which lacks something, which may be characteristic of a written work. The author of the article considers the main classes of lacunae, among which are: 1) generic lacunae, which reflect the absence of a common name for a class of objects; 2) species lacunae are the absence of specific names, names of individual types of objects or phenomena; 3) intralingual lacunae are found within the paradigms of one language; 4) interlanguage
... Show MoreLO Hamza, NA Al-Mansor, J. Entomol. Zool. Studies, 2017 - Cited by 14
Background: Mother-infant bonding is an important psychological step postpartum and disturbed relationship may carry dramatic consequences as a psychological disorder which may affect the periodontal health of the mother. The aim of the present study was to assess the effect of the postpartum Mother-infant bonding on their periodontal condition. Materials and Methods: Mothers in the postpartum period with age range 20-35 years were subjected to postpartum Bonding Questionnaire (PBQ). Periodontal health status was assessed by measuring probing pocket depth and clinical attachment level. Results: The mean values of both probing pocket depth (PPD) and clinical attachment loss (CAL) were higher among disordered mothers than mothers with normal
... Show MoreThe nature of the political system of any country in the international system must have an impact on the policy of the State, whether in the interior or exterior, both regional and international, Turkey is one of the most important countries in the Middle East, which have a place and effectiveness on the surrounding environment, hence the importance of research lies in its political system and the transfer of power in it and its transformation from the form of the parliamentary system to the presidential system of the repercussions of the task and mutual effects between Turkey and the countries of the surrounding region in terms of the extent of achieving political stability in the Turkish interior or not and how this can be refl
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