Preferred Language
Articles
/
joe-2194
Performance Analysis of Four Conceptual Designs for the Air Based Photovoltaic / Thermal Collectors
...Show More Authors

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%.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
Build a scale to measure the moral reasoning of students at the preparatory stage in Baghdad
...Show More Authors

    The moral aspect is an important one in the structure of personality , and the lack of moral aspect is responsible for what we suffering today from problems . there is no exaggeration to say that many of our current problems are moral problems , and reflects the lack of moral growth.                            

 The goal of research is to build scale in order to detect the level of moral reasoning among junior high school students in Baghdad , The researcher followed the procedures in the construction of scientific standards in order to measur

... Show More
View Publication Preview PDF
Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
Problems lead to the low level of academic achievement in the evening school: suggestions and solutions
...Show More Authors

Academic achievement is a professional standard for measuring student levels in the first stages. Therefore, any indication of the level of achievement makes us in an attempt to employ students in evening schools. The researcher has developed a closed questionnaire of (36) paragraphs. A total of (164) male and (24) female students were chosen from evening schools. The result of this research revealed that the number of students was a reason for the low level of their achievement, the lack of laboratories, educational methods, and techniques of the most prominent problems confirmed by students in these schools. In addition, to support educational institutions with their necessary needs. The most important conclusion in this research is th

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 30 2021
Journal Name
College Of Islamic Sciences
(General corruption is an approach to tyrants and unjust in the perspective of the Holy Quran)
...Show More Authors

      That corruption with all its forms,  has prevailed over the whole world, but  with  different degrees relaying on the one who leads these countries of rulers, followers and officials who have been deemed  the main reason for that corruption, but if these  rulers  were righteous, These countries would have blessed and elevated and were corrupt unjust tyrants who were the disaster that befell the chiefs of those countries  with ruin, misery, and backwardness. This is what we sought to prove and clarify by considering the verses of the Holy Qur’an in respect with this topic. The research includes an introduction, two topics, and a conclusion.

   &nbsp

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 30 2015
Journal Name
College Of Islamic Sciences
Forced State Fair Workers "Trades and professions" To work from the perspective of the Islamic economy
...Show More Authors

The origin of occupations and trades producing goods and services necessary for the members of society
When people are designated to perform this task, in which case the state of change is included in the imposition of adequate labor rights, and may change from imposing sufficient to imposing the eye
Does the state have the right to compel "tradesmen and professions" to do their jobs?
Therefore, this research came to address the legitimacy of this from the perspective of the Islamic economy.

View Publication Preview PDF
Publication Date
Tue Dec 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
The importance of improved forests in Iraq and their impact on the economic and social future
...Show More Authors

عانت الغابات في العراق قصوراً واضحاً في مجال إشباع حاجة السكان لمنتجاتها الرئيسية المتمثلة بالأخشاب ومنتجاتها الثانوية المتمثلة بالأغصان والأوراق والنباتات الطبيعية والحيوانات البرية ونواتجها الأخرى، مما يتطلب التفكير بمحاولة إيجاد سبل جديدة لحل هذه المشكلة الاقتصادية المرتبطة بعنصريها الحاجة للأخشاب والأموال المخصصة لتطويرها عموماً.

لقد دمرت مساحات كبيرة من الغابات وحرقت وقطعت من

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The causal relationship between debt size and Economic value added With contrast of the Frim Size
...Show More Authors

Abstract

       The research aims to identify  the  nature of  the relationship between the level of debt used  and economic  value  added  of companies listed on the Iraq Stock Exchange under the Contrast sizes of these companies , The research addressed the theoretical concepts associated with each of the debt financing , economic added value and Organization size With the use of financial techniques in the practical side to measure these variables, The research community Represent of  the shareholding companies listed on the Iraq Stock Exchange with a choice of intentionally sample of 24 joint stock companies representing&nbsp

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Fri Dec 27 2024
Journal Name
International Journal Of Design & Nature And Ecodynamics
Amino Acid and Hormonal Profiling of the Adrenal Gland in the Pin-Tailed Sandgrouse (Pterocles alchata)
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Engineering
Modeling and Optimization the Influence of CO2-MAG Welding Parameters on the Weld Joint Shape Factors
...Show More Authors

This paper represents an experimentalattempt to predict the influence of CO2-MAG welding variables on the shape factors of the weld joint geometry. Theinput variables were welding arc voltage, wire feeding speed and gas flow rate to investigate their effects on the shape factorsof the weld joint geometry in terms of weld joint dimensions (bead width, reinforcement height, and penetration). Design of experiment with response surface methodology technique was employed to buildmathematical models for shape factors in terms of the input welding variables. Thepredicted models were found quadratic type and statistically checked by ANOVA analysis for adequacy purpose. Also, numerical and graphical optimizations were carried out

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 30 2015
Journal Name
College Of Islamic Sciences
Imam al - Karji replies to some Islamic groups In his book the jokes of the Koran
...Show More Authors

Imam al - Karji replies to some Islamic groups
In his book the jokes of the Koran

View Publication Preview PDF
Publication Date
Sun Mar 01 2020
Journal Name
Astrophysics And Space Science
The compound stream event of March 20-25, 2011 as measured by the STEREO B spacecraft
...Show More Authors
Abstract<p>The interaction of interplanetary coronal mass ejections (ICME) with each other and with co-rotating interaction regions (CIR) changes their configuration, dynamics, magnetic field and plasma characteristics and can make space weather forecasting difficult. During the period of March 20–25, 2011, the Solar Terrestrial Relation Observatory (<italic>STEREO</italic> B) encountered a compound stream containing several interacting structures. Our analysis suggests that the stream consists of two ICMEs followed by an embedded ICME/CIR. The sudden appearance of the third ICME within the fast wind side of the CIR causes the proton temperature(<inline-formula><alternatives><tex-math></tex-math></alternatives></inline-formula></p> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref