Solar photovoltaic (PV) has many environmental benefits and it is considered to be a practical alternative to traditional energy generation. The electrical conversion efficiency of such systems is inherently limited due to the relatively high thermal resistance of the PV components. An approach for intensifying electrical and thermal production of air-type photovoltaic thermal (PVT) systems via applying a combination of fins and surface zigzags was proposed in this paper. This research study aims to apply three performance enhancers: case B, including internal fins; case C, back surface zigzags; and case D, combinations of fins and surface zigzags; whereas the baseline smooth duct represents case A. A 2D, steady-state simulation model that took into account the impact of the convective flow of air circulating inside the PVT system in addition to radiative and convective heat losses from the front PV surface was developed and validated via previous tests. The results revealed that, under the same volume requirements, the application of surface zigzags is preferred for airflow rates of 0.06 kg/s or less, whereas the introduction of fins is preferred for higher airflow rates. The results also revealed that, of the three cases considered, the introduction of the fin–surface zigzag combination is the most effective and has the potential to improve the electrical and thermal efficiency by ~26% and 3%, respectively.
Construction projects need methods and techniques to ensure the level of quality and commensurate with the level required and documented in the project contract. The quality of the project is affected by the quality of the inputs and accompanying procedures in the construction of the project.
Al-Rumaitha residential project found that the quality of the concrete for the ceilings in the research sample (the roof of the third floor of buildings A25 and A26) and (roof of the second floor of buildings A27, A28, A29, A30, A31, A32 and A33) and roof of buildings A15 and A16 A19)) is not the required quality level.
The idea of the research came after the need to improve the performance o
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The project of balad's major sewerage system is one of the biggest projects who is still in progress in salahulddin province provincial - development plan that was approved in 2013 . This project works in two parts ; the 1st is installing the sewerage networks (both of heavy sewerage & rain sewerage) and the 2nd is installing the life – off units (for heavy sewerage & rain sewerage , as well) . the directorate of salahuiddin is aiming that at end of construction it will be able to provide services for four residential quarters , one of the main challenges that project's management experience is how to achieve thes
... Show MoreThe researches discusses the style of acting used by (Sami Abdul-Hameed) in one of the play director (Salah AL-Kassab) production whine he called; Picturesque.
The problem of this research is to discover the differences between the performance of (Sami Abdul-Hameed) in the Picturesque Theatre and the other theatre.
The goal of the research is to get to know the style of acting used in (king Lear) directed by (Salah AL-Kassab).
After defining the term (picturesque theatre), the researcher discusses the elements of the Visual theatre and the components of the stage picture according to (Alexander Dean) and he refers to those well-known director who had emphasized the Visual elements. Such as (Gordon Grieg) and (Franco Zeferrel
The personality characteristics of the Leader are considered one of the main elements to reach into business organizations entrepreneurship; and because of the development of the organizations of the continuous transformations as result of huge Competition in private High Education sector, there is a great need for Leaders characterized of certain personality capable of managing their organizations and can positively effect on them. Also these organizations' success to reach into entrepreneurship requires a main significant element that is (strategic flexibility) which is considered one of the important elements for success.
Accordingly, this research is trying to fin
... Show MoreHands have consistently been an important vehicle in the transmission of disease (1). Thus, thorough hand-washing remains the single most important factor in preventing infection specially in hospitals and labs.Twenty-nine non-clinical volunteers (do not work or come in contact with a clinical or hospital setting) that lacked visible skin injuries, eczema or apparent skin disease were used, those subjects were all tested by a material of each of the three used in the study weekly and laboratory tests were done pre- and post washing.All three material were effective , Eugenol extract as effective as the bar and lotion soap. And this was confirmed statistically.Eugenol has a great antibacterial action even in small concentration and t
... Show MoreExperimental densities, viscosities η, and refractive indices nD data of the ternary ethanol+ n-hexane + 3-methyl pentane system have been determined at temperatures 293.15,303.15 and 313.15 K and at atmospheric pressure then these properties were calculated theoretically by using mixing rules for densities, viscosities and refractive indices .After that the theoretical data and the experimental data were compared due to the high relative errors in viscosities an equation of viscosity was proposed to decrease the relative errors.
Abstract Physical requirements are an important priority for the development of football gymnastics coaches because the nature of performance is interconnected and interconnected in terms of the player's duties in the match. In the gameplay situations, the player must perform the skill with strength and speed coupled with accuracy and the reactions of the colleague and competitor alike, which represents the normal reality of the football gymnasium Skilled exercises are one of the most suitable technical side exercises as they are built according to the components of the skill requirements of the game and the nature of its performance, which appear on the gro
... Show MoreThe importance of this study lies in shedding the light on the impact of Islam and Prophet Mohammed (peace be upon him) on the western culture and English literature in particular. While some writers were looking at Islam as a dangerous element, others were completely taken by the oriental spirit of Arabic and Islamic culture and glorifying it. Writers from Chaucer to later ones mostly make references to this impact showing how vast was the gap of misunderstanding between the east and the West. Thus, this study aims at breaking the barrier between East and West in its three sections as it introduces the meaning of Islam and its common features with other religions in the first section. The second section briefly presents writers’ reflecti
... Show MoreTransgenic plants offer advantages for the manufacture of recombinant proteins with terminal
mannose residues on their glycan chains. So plants are chosen as source of pharmaceutical products and for
the development of alternative expression systems to produce recombinant lysosomal enzymes. In the
present study the sequence of the natural cDNA encoding for the human lysosomal enzyme
glucocerebrosidase (GCD) was modified to enhance its expression in soybean plants. The glucocerebrosidase
gene signal peptide was substituted with that signal peptide for the Arabidopsis thaliana basic endochitinase
gene to support the co-translational translocation into the endoplasmic reticulum (ER), and the storage
vacuol