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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
Fri Nov 12 2021
Journal Name
مجلة اداب الفراهيدي
دور القنوات الفضائية العراقية في تشكيل اتجاهات الشباب ازاء قضايا المجتمع ومشكلاته
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Publication Date
Sat Apr 01 2023
Journal Name
Baghdad Science Journal
Influence of Glow and Afterglow Times on the Discharge Current of Argon at Low Pressure
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     An experimental investigation of the variation of argon discharge current with a glow and afterglow time intervals of a square discharge voltage was carried out at low pressure (6-11 mbar). The discharge was created between two circular metal electrodes of diameter (7.5 cm), separated horizontally by a distance (10 cm) at the two ends of a Pyrex cylindrical tube. A composite of two Gaussian functions has been suggested to fit and explain the variation graphs clearly. It is shown that the necessary times of glow and afterglow needed to attain a maximum discharge current are (70 us) and (60 us), respectively. The discharge current is observed to drop to the lowest value when the two times are serially longer than (85 us) and (72 u

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقويم كفاءة أداء الاستثمارات بحث تطبيقي في شركتي التأمين الوطنية والتأمين العراقية
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This study attempts to highlights on the evaluation of performance efficiency for Investments in both National & Iraqi Insurance companies for the years 2001-2010 and their importance on those companies and the economy of the country in order to find  out the investment areas and to compare between investment activity and its revenues as well as to compare performance of both companies in investment field.

The study was based on annual reports and balance sheets of both companies. In many chapters, this study dealt with theoretical and practical aspects of the investments and its revenues. Key hypothesis was based on this study, including four parts of Sub hypotheses about (statistical effective relationship between the

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Publication Date
Mon Jan 23 2023
Journal Name
Arab Science Heritage Journal
العمق الوجداني والانفعال العاطفي لدى شعراء القرنين السابع والثامن الهجريين في الأندلس
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 The Andalusi did not leave any poetic art without expressing his psychological and sentimental emotions and the depth of emotions and it sincerity. We found Andalusian translated his emotions into poetry and in many different subjects. The Poetic images and the analogies were plentiful in their poetry.

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Publication Date
Sat Dec 29 2018
Journal Name
Journal Of Planner And Development
(دراسة تحليلية في ظاهرة تقسيم الوحدة السكنية ( منطقة الدراسة: محلة 409 الكاظمية
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Publication Date
Fri Dec 03 2021
Journal Name
مجلة تكريت للعلوم السياسية
نظرية الاعتراف في الفكر السياسي الغربي المعاصر: أكسل هونيث ونانسي فريزر انموذجا
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يعيش المجتمع العالمي أزمات بنيوية ونسقيه عميقة واختلالات وظيفية أسهمت في تنامي مظاهر الصراع المختلفة واشتداد تفجر الأزمات الهوياتية وتزايد الامراض الاجتماعية المقضة للعيش المشترك والمربكة لمظاهر التعايش والتآلف مع لجوء إنسان العصر الحالي الى التقوقع والاحتماء والانزواء تحت هويات ضيقة ونحل صغيره في مشهد يظهر مدى تراضي شبكة العالقات الاجتماعية على أداء وظائفها وأصبح عندها الاغتراب والقلق واللاتضامن والع

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Publication Date
Tue Jun 19 2018
Journal Name
Elmofaker Review
The Secondary Liability of Electronic Auctions Arising from Contributory Trademark Infringement – A Comparative Study
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Despite the global economic downturn, online e-commerce, especially the sale of counterfeit goods, continues to witness a rise in sales, and one of the important players in e-commerce is the owners of e-commerce auction sites. Although they do not have a direct role in trademark infringement, they still consider them indirectly responsible (secondary liability) for infringing on their trademarks. Thus, many cases have been filed by the owners of the original trademarks (which have been infringed by persons who have sold some of the goods and products that are imitating their marks through some electronic auctions) against the owners of those auctions. In view of the international character of the Internet, in different countries, and despit

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Publication Date
Fri Mar 20 2026
Journal Name
المجلة العراقية للعلوم السياسية
موقف الامارات العربية المتحدة من الصراع الداخلي في السودان بعد العام 2019
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ان الصراع الداخلي السوداني مابين قوات الدعم السريع وقوات الجيش السوداني والذي يشير الى حدوث اكبر ازمة انسانية عالمياً مرتبط بالتفاعلات الخارجية للدول الاقليمية وتعد دولة الامارات العربية المتحدة أكثر الدول التي تُثار حولها الاتهامات بشكل متكرر. لذا تهدف هذه الورقة البحثية الى دراسة العلاقة مابين دولة الامارات العربية المتحدة والصراع في السودان مستخدماً المنهج الوصفي التحليلي ومن خلال الدراسات العلمية و

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Publication Date
Wed Sep 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
التحليل الاحصائي لتجارب القياسات المكررة للبيانات المصنفة في حالة معالجتين وثلاث معالجات
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من اهداف بعض التجارب هي معرفة تاثير التسلسلات المختلفة لبعض الادوية او التغذية او تجارب التعلم. وفي بعض الاحيان قد تكون الوحدات التجريبية نادرة لهذا نقوم باستخدام الوحدات التجريبية على نحو متكرر. او بسبب الميزانية المحدودة فان صاحب التجربة يخضع كل وحدة تجريبية لاختبارات عديدة ويطلق على هذا النوع من التجارب التي يتم فيها استخدام الوحدات التجريبية (الاشخاص) Subject على نحو متكرر

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Publication Date
Sun Jun 30 2019
Journal Name
Journal Of The College Of Education For Women
Qualities of Life Partner from the Perspective of a Sample of University Students
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The study aims at identifying the morphological and psycho-socio-economic qualities wished to be in a life partner among a sample of Palestinian youth. The total sample was (231) and consisted of  (83) male and (148) female students. Each student presented a detailed report on the qualities he/she wished to be in life partner. The study used the descriptive approach and content analysis method. The validity and stability of the analysis were calculated. The results showed eight qualities in both groups: physical, psychological, emotional, social, intellectual, familial, economic and academic. Female students were found to have more variations than male students in terms of the qualities preferable in the life partner. Male students

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