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%.
Many diseases can produce cardiac overload, of these disease hypertension, valve disease congenital anomaly in addition to many other disease. One of the most common diseases causing left ventricle overload is hypertension. A long term hypertension can cause myocardium hypertrophy leading to changes in the cardiac contractility and reduced efficiency. The investigations were carried out using conventional echocardiography techniques in addition to the tissue Doppler imaging (TDI) from which many noninvasive measurements can be readily obtained. The study has involved the effect of hypertension on the myocardium stiffness index through the measurement of early diastolic filling (E) and the early velocity of lateral mitral annulus (Ea
... Show MoreThis research deals with the motives of the use of Facebook by elderly people and the achieved needs, which leads the researcher to ask an important question: why an old persons use Facebook and are the achieved needs through which they got? The research aims to find out the habits and patterns of using Facebook by old men and stands on the main motives of the elderly in their use of Facebook. It also identifies the most prominent needs that have been made for the elderly as a result of their use of Facebook.
The research is a descriptive one in which the researcher uses survey method to achieve the desired goals. The researcher has chosen a group of old men from Diyala province. The total sample number is about
... Show MoreA revised checklist of the robber fly genera (Diptera, Asilidae) was given during this study in Iraq. The investigation showed (21) genera belonging to seven subfamilies, two genera new recorded to entomofauna of Iraq (Promachus Loew, 1848 and Genus: Dysmacus Loew, 1860). Eight genera showed in this investigation and eleven genera were recorded previously to Iraq.
Through the last decade, Integrated Project Delivery (IPD) methodology considers one of the new contractual relations that are also on the way to further integrate the process of combining design and instruction. On the other hand, Building Information Modeling (BIM) made significant advancements in coordinating the planning and construction processes. It is being used more often in conjunction with traditional delivery methods. In this paper, the researcher will present the achievement of IPD methodology by using BIM through applying on the design of the financial commission building in Mayssan Oil Company in Iraq. The building has not been constructed yet and it was designed by usin
In the present study twenty samples of human urine were taken
from healthy male and female with different of: ages, occupation and
place of residence. These samples were collected from the hospital to
measure the concentration of radon gas in human urine by using one
of solid state nuclear track detectors LR-115.
The results obtained of the concentrations of radon in healthy human
urine are varying from 2.12×10-3 Bq.l-1 to 4.42×10-3 Bq.l-1 and
these values are less than the allowed limits 12.3×10-3 Bq.l-1.
This paper addresses the new coloring in the concept of dystopian society as represented by the positive role of one of the characters vs. the passive role of the government and its mutual effect on the people of the society. In addition, it describes how all men in the dystopian society victimize and degrade the other through unlawful acts, like: stealing, rape, and fear, which are the lowest points in a moral decay. However, it offers hope by illustrating a positive sense, as exemplified by the doctor's wife out of Saramago's optimistic view that men may be descended from good women. Accordingly, the paper aims to examine the effect of the government’s role in the lives of the people who have later turned into blind in a dystopian so
... Show MoreThe building of Basrah University located in a rural area at Gramat Ali, its consist of seven colleges and very high number of students, lecturers ,and employers. Therefore, the intersections which leading to university building suffer congestion at morning peak hour (8-9) A.M and evening peak hour (2-3) P.M. In this study we collected the data in intersections which leading to university building at peak hour at same time, then we had analysis this data by using the highway capacity manual (HCM) and program (HCS). Also, we collected that data in University entries with classification of vehicles according to types and number of passengers at peak hour. Then we studied the number of proposals to riddance the congestion, such as the effe
... Show MoreThe adoption of the concept of preventive war in any country especially in a country like the United States result in a lot of serious consequences, so that pre-emptive military action may alter certain regional arrangements based on the basis of political and security balance, and reduce the incidence of tensions that may worsen a sudden during the application of preventive war, so the concept is applicable to be a risk much more when you face the reality and that because the issues more importantly, it should prepare a detailed and careful study of the post –stage of the use of preventive military action and this requires realy no papers insist or documents discuss this but accurate this field study of the situation thereafter.
The aim of this research is to uncover the science processes included in the teacher’s guide to scientific experiments for science books for grades (first-second) for the intermediate stage, The research sample included all the scientific experiments contained in the teacher’s guide for scientific experiments for the intermediate stage, The researcher used the descriptive and analytical method, and designed an analysis tool, The content of science operations, and verified its validity and consistency, and after using percentages and ranks for statistical treatment, the research reached the following results: The number of practical experiments varies from one class to another in the intermediate stage, where the highest percentage ap
... Show MoreIn this research, I have tried to explain about the prophets' peace be upon them sent by God which is one of the commonalities between Islam and Judaism, but the two religions are different about whether the prophets are infallible or not. This study has tried to independently explain to describe both Islam and Judaism on this subject. Eventually, we concluded that there is a big difference between the two religions regarding their view of the infallibility of the prophets of all sins.