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alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
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A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.

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Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
The effect of dramatizing characters within the social subject of the basic education stage on student achievement
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The researcher used the experimental approach due to its suitability and the nature of the research problem. The research community was represented by the eighth-grade students in the Rozak Elementary Mixed School affiliated with the General Directorate of Education in Erbil / the center, for the academic year (2021-2022), the number is (96) students, and the research sample consisted of (63) male and female students, with (31) in the experimental group, and (32) in the control group, and (11) students were excluded by (5) students from the experimental group, and (6) students from the control group, as the excluded, are students who failed and were absent from the lessons, and accordingly, the research sample became composed of (52) mal

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Publication Date
Tue Feb 25 2025
Journal Name
Al–bahith Al–a'alami
IRAQ YOUTH TRENDS TOWARDS CELEBRITY ADVERTISEMENTS ON SOCIAL MEDIA : (A research taken from a Master Degree thesis)
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In the light of what is witnessing in the advertising arena of new ways and methods in delivering advertising message to consumers by finding new outlets to communicate with them especially through social networking sites, which became the first choice of advertising companies in order to spread its goods and services. These companies now are relying gradually on celebrities to appear with their products and goods to drive the audience's  attention towards them. The thesis aims to find out the attitudes of young people towards the the advertisements that show famous celebrities on social networking sites. The researcher used survey method which aims to record, analyze and interpret the phenomenon after collecting the necessa

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
بعض الاضطرابات السلوكية والانفعالية والانفعالية وعلاقتها بالاستعمال المفرط للألعاب الالكترونية لدى التلاميذ في المرحلة الابتدائي
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سعى البحث الحالي الى التعرف على بعض الاضطرابات السلوكية والانفعالية وعلاقتها بالاستعمال المفرط للالعاب الالكترونية لدى تلاميذ المرحلة الابتدائية, إذ يواجه التلاميذ مشكلات سلوكية عديدة ،تظهر من خلال تعاملهم مع اقرانهم في البيت او في المدرسة والتي قد تتطور عند بعضهم وتتحول الى اضطرابات نفسية،مما يؤدي بهم الى ضعف التعلم وسوء التوافق في حياتهم المدرسية ويصبحون عُرضة للا صابة بالامراض النفسية ،إذا لم يتم تشخ

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Publication Date
Fri Dec 30 2022
Journal Name
Journal Of The College Of Education For Women
The Effect of Cognitive Strategies on Iraqi EFL College Students’ Writing Anxiety
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Writing in English language demands both mental skills and a suitable level of language proficiency. Some studies showed that writing anxiety has an impact on the acquisition of language learning. This study; however, teaches the cognitive strategies (PLAY & WRITE) as a writing strategy, so as to decrease students’ use of it when experiencing writing anxiety at the academic writing level. The sample has been (100) second-stage Department of English learners at the College of Education (Ibn –Rushd), in the University of Baghdad-Iraq. They have been randomly selected and divided into experimental and control groups; (50) students in each group. To achieve the objective of the study, SLWAI questionnaire has been distributed to the e

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
التخطيط التخطيط العمراني والسكاني لمدينة بغداد في عهد الوالي العثماني محمد رشيد الكوزلكي 1852-1857
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I've dealt with my research is marked by ((urban and population planning for the city of Baghdad, during the reign of the Ottoman governor Muhammad Rashid Alkozlki 1852-1857)), a set of facts and incidents historical with the physical and demographic dimension, which passed on the history of the city of Baghdad on the fifth of the nineteenth century the contract during the Ottoman control Iraq, which lasted almost nearly four centuries

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
اختبار العلاقة بين التدفقات النقدية والعوائد المتحققة للاسهم: دراسة تطبيقية في سوق العراق للاوراق المالية
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غالبا ما يؤكد موضوع تحليل البيانات المالية على اختبار عناصر التدفق النقدي لغرض النتبؤ بعوائد الاسهم بالمستقبل ، فضلا عن ان المستثمرين دائما ما يبحثون عن زيادة عوائد الاسهم، وان مثل هذا النوع من التحليل يمكن استخدامه لطبيعة المعلومات المحتواة في عناصر التدفق النقدي ، والدرجة التي على اساسها تنعكس مثل هذه المعلومات المالية في اسعار الاسهم من خلال تقويم القيم السوقية للأوراق المالية فتؤدي إلى تغيير قرارات م

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Publication Date
Tue Feb 25 2025
Journal Name
Journal Of Baghdad College Of Economic Sciences University
العلاقة بين القدرات المعرفية وتمكين العاملين بحث تحليلي في هيئة رعاية ذوي الاعاقة والاحتياجات الخاصة
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Publication Date
Thu Nov 16 2023
Journal Name
مجلة كلية الإمام الكاظم
الوعي بالمسؤوليةً البيئيـة عنـد طلبـة الكيـمياء فـي كــلية التـربية للعلـوم الصـرفة – أبن الهيثم في العراق
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Publication Date
Mon Mar 01 1999
Journal Name
مجلة الاستاذ للعلوم الانسانية والاجتماعية
اخلاقيات مهنة العاملين في المكتبات المركزية الجامعة بغداد والمستنصرية والتكنولوجية من وجهه نظر المستفيدين منها.
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يهدف البحث إلى معرفة ما هيه اخلاقيات مهنة العاملين في المكتبات وتحديث متطلباتهم الضرورية من المهنة لكي يسمو بأخلاقياتها ، وهل هذه الاخلاقيات متوافرة في العاملين في مكتباتنا الجامعية ضمن حدود الدراسة ؟ ومن ادوات جمع البيانات : استمارة بالاخلاقيات وزعت على مجموعة من الاساتذة و استبانة وزعت على من المكتبات الجامعية . وكان مجتمع الدراسة العاملون في المكتبات المركزية الأولى والثانية لجامعة بغداد والمكتبة المرك

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Publication Date
Mon Aug 01 2022
Journal Name
مجلة الجامعة العراقية
المكتبة الاسلامية الرقمية مشروع صناعة مكتبة رقمية للطالب في قسم علوم القران الكريم والتربية الإسلامية
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تهدف الورقة البحثية الى اعداد مشروع لصناعة مكتبة رقمية للطالب في قسم علوم القران الكريم والتربية االسالمية في كلية التربية ابن رشد للعلوم االنسانية / جامعة بغداد ، اعدت الباحثة استمارة نموذج كوكل تضمنت مجموعة من االسئلة الغرض منها تحديد المؤلفات االساسية التي يحتاجها طالب العلوم االسالمية في دراساته وابحاثه ،واعتمدت الباحثة على المنهج الوصفي اسلوب المسح لجمع البيانات ، ووزعت االستمارة عبر الصفوف االلكترو

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