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Experimental Study Using the Passive Solar Chimney for Evaporative Cooling With PCM and CFM as a Thermal Energy Storage
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      In this work, a test room was built in Baghdad city, with (2*1.5*1.5) m3  in dimensions, while the solar chimneys (SC) were designed with aspect ratio (ar) bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB) that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled  in the bottom of TESB of vertical SC. The TESB was made from metallic iron sheets as a shell and fuelled by paraffin wax as phase change material (PCM). The PCM supported by copper foam matrix (CFM) to enhance thermal conductivity of wax. When heat is released from TESB to the air, a buoyancy force will be generated in chimney gaps. Then a difference in pressure between inside and outside test room leads to induce the air flow to test room through wet corrugated cellulose pad, where evaporative cooling (EC) occurs. Results of experimental work, that achieved in June, for 12 to24 hour in the test day, refer to effectiveness using EC to decrease the room temperature comparing. The system reduces test room temperature of up to 8.5~9.2 oC in 11:00 am to 3:00 pm and at highest effectiveness of EC, while minimum reduces in temperature of up to 3.5 oC in 8:00pm to 3:00 am. Also, the results showed the affectivity to using the TESB, during the night time for ventilation and EC, with lower effectiveness than from day time. The range of EC effectiveness equals 30.5-37.5 with a natural vent, while The maximum air change per hour (ACH) equals (3.8-6.187), and the maximum mass flow rate is equal to (36.651 kg.hr-1) at experimental evaluation of the system’s discharge coefficient value 0.371.

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Impact of Manager Roles in Achieving Organizational Excellence
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The current research problem is focused on the level of human resource managers' performance of their contemporary roles and the impact of this on achieving organizational excellence. The research aims at diagnosing and interpreting the nature of the relationship between the roles of human resource manager and organizational excellence. ), And oil companies located in Baghdad governorate. The research included (boards of directors), and collected data from (83) respondents representing the research community exclusively and comprehensively

represented in the positions of function (Directors-General, Associate Directors-General, heads of departments, divisions and divisions). (49) questions, as well as th

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة بعض المقدّرات الحصينة في دوال التمييز بأستخدام المحاكاة
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The development in manufacturing computers from both (Hardware and Software) sides, make complicated robust estimators became computable and gave us new way of dealing with the data, when classical discriminant methods failed in achieving its optimal properties especially when data contains a percentage of outliers. Thus, the inability to have the minimum probability of misclassification. The research aim to compare robust estimators which are resistant to outlier influence like robust H estimator, robust S estimator and robust MCD estimator, also robustify misclassification probability with showing outlier influence on the percentage of misclassification when using classical methods. ,the other

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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
إسهامات علماء العرب والمسلمين القدامى في إثراء علوم الرياضات
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     Arab and Muslim scholars have made influential contributions to the development of mathematics by providing it with many achievements and inventions. This research presents the most important of these achievements and assistance in mathematics during the period of the Islamic Renaissance for different Arab and Muslim Scholars. One of the clearest and most prominent examples of these achievements is the establishment of the science of algebra and the discovery of zero and added to the numbers by the Muslim Scholar of Al-Khwarizmi, which facilitated the solution of many arithmetic problems and issues to this day.

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Publication Date
Sun Apr 01 2012
Journal Name
Journal Of Educational And Psychological Researches
Effectiveness of at site electronic learning/teaching in educational development
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 This study investigated three aims for the extent of effectiveness of the two systems in educational development of educators. To achieve this, statistical analysis was performed between the two groups that consisted of (26) participants of the electronic teaching method and (38) participants who underwent teaching by the conventional electronic lecture. The results indicated the effectiveness of the “electronic teaching method” and the “electronic lecture method” for learning of the participants in educational development. Also, it indicated the level of equivalence from the aspect of effectiveness of the two methods and at a confidence level of (0.05). This study reached several conclusions, recommendations, and suggestio

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Publication Date
Mon Dec 01 2008
Journal Name
Political Sciences Journal
العلوم السياسية في العراق بداياتها ، نشأتها ، تطورها ، ومفرداتها التدريسية
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العلوم السياسية في العراق بداياتها ، نشأتها ، تطورها ، ومفرداتها التدريسية

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Publication Date
Thu Jul 29 2021
Journal Name
Arab Science Heritage Journal
اللغة ما بين العامية والفصحى في مجلة لغة العرب
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The Arabic language is one of the important magazines that issued in our contemporary history not only on the Iraqi level but according Arabic one as well because it considered

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Publication Date
Tue Jul 01 2008
Journal Name
Journal Of Educational And Psychological Researches
" الصعوبات التي تواجه طلبة الدراسات العليا في أعداد البحوث
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تتزايد الصعوبات التي يعاني منها الطالب بشكل خاص والتدريسي بشكل عام في المرحلة الراهنة وذلك لنقص المصادر والكوادر العلمية الرصينة التي كانت تفخر بها جامعات العراق ولا سيما جامعة بغداد اذ أن الجامعات هي اعلى قيمة في السلم التعليمي وتعد بيئة نقية أوجدها المجتمع للتربية من خلال المناهج الدراسية التي تؤدي بشكل سليم وان الجامعة بوصفها سياقاً اجتماعياً لها أهمية في التشجيع على الإبداع وتعد جيلاً من الشباب للعمل

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Publication Date
Wed Oct 01 2008
Journal Name
Journal Of Educational And Psychological Researches
برنامج لتقويم اداء رؤساء الاقسام العلمية في الجامعات العراقية
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مشكلة البحث

       لقد حدا بالمهتمين في الميدان التربوي، والادارة التربوية بصورة خاصة، ان يجدوا علاقات ايجابية بين متغيرات الميدان التربوي عامة والاداري بصورة خاصة وقد تمخض هذا عن وجود علاقة ايجابية بين اداء المديرين ورؤساء الاقسام ودرجة التقويم، ومن هنا يتضح انه كلما كان التقويم عالياً في درجته، يتضح ان هناك اداءً فاعلاً ولكن ليس بالشكل الحقيقي لمعنى التقويم ما لم يكن هناك

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Publication Date
Tue Mar 15 2022
Journal Name
Arab Science Heritage Journal
الري والإصلاح الزراعي في العراق (1-132هـ/ 622-750م)
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The organization and development of the irrigation system and agrarian reform in Iraq had an impact on the diversity of its methods and uses

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Publication Date
Sun Jun 30 2019
Journal Name
College Of Islamic Sciences
Itentional deliberative in Surat Al-Zumar M. Sheeda Khader Karim
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This research deals with deliberative intentionality in its two dimensions, deliberative intent, direct, and indirect deliberative intent, and deliberative intentionality assumed great importance to ancient and contemporary scholars. The text, relying on deliberative intent as a methodology concerned with the study of language in usage, and the research focuses on direct deliberative intent through (the intent of acceptability, the intent of the presumption, the intent of the informational, the intent of interaction), and the indirect deliberative intent through (the intentionality of the case, the intent of the metaphor, The intent of the communicative impulse, the intent of the allusion,), and these deliberative elements activate and c

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