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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
Sun Dec 01 2024
Journal Name
مجلة دراسات دولية
توظيف خيارات استراتيجيات مكافحة التطرف العنيف في العراق وافاقها المستقبلية
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أن للتطرف العنيف أسباب متنوعة تقف وراء ظهوره وتمدده في دول العالم المختلفة على نطاق واسع، إذ إن لكل بيئة ظروفها وخصوصياتها الكلية والفرعية التي تسهم في تعزيز القدرة التأثيرية للسلوكيات العنفية في إطار مجتمع ما، لاسيما إذا علمنا إن التطرف العنيف المؤدي الى الإرهاب كسلوكيات عنفية متطرفة مدمرة للبناء المجتمعي ما كان ليستمر لولا وجود بيئة حاضنة وظروف تساعد في انتشاره واستمرارية قدراته التأثيرية في البناء السي

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Publication Date
Tue Mar 05 2002
Journal Name
جامعة بغداد كلية اللغات
المحسنات البلاغية في الترجمة العبرية لرواية اللص والكلاب لنجيب محفوظ
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تم اكمال الملاخص

Publication Date
Tue Jan 01 2019
Journal Name
حوليات اداب عين شمس
فعل الامر من صيغة N المبني للمجهول في اللغة الاكدية
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يتناول هذا البحث موضوع (( فعل الامر في صيغة المبني للمجهول في اللغة الاكدية )) وهو يتعلق بقواعد اللغة الاكدية , وقد تضمن هذا البحث مقدمة وشقين : صيغة المبني للمجهول وفعل الامر. اما ما يخص المقدمة فقد شملت تعريف الفعل وانقساماته حسب قوة احرفه , الجذر , المعنى , والفاعل , كما تضمنت المقدمة أيضا الحديث عن الصيغ الفعلية الرئيسة الأربعة التي يتألف الفعل الاكدي منها إضافة الى الصيغ الثانوية التي تتضمنها الصيغ الرئيسة . و

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Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
Selective Visual Attention among Students of Colleges of Education At The University Of Mosul
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The research aims to identify the level of selective visual attention among students of the faculties of education at the University of Mosul. To achieve the goal of the research, the researchers chose a stratified random sample of students from the faculties of education at the University of Mosul for the academic year (2020-2021). The sample size was (652) students from the scientific and humanitarian specializations, the second and fourth stages. The researchers developed a test of multiple-choice to measure the selective visual attention, which consisted of (42) items. The results revealed that the students of the faculties of education for human sciences have an appropriate level of selective visual attention. There are statisticall

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Publication Date
Mon Jan 01 2007
Journal Name
Journal Of Educational And Psychological Researches
اتجاهات الشباب نحو استخدام العنف ضد المرأة في مدينة بغداد
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تشير الادبيات الى ان العنف قد رافق الانسان منذ بدء الخليقة حتى يومنا هذا، الا ان التطور العلمي والتكنلوجي والسرعة الفائقة في التغيير قد زاد من حجمه، وعدد مثيراته واختلفت نوعيته تبعاً لارتقاء الانسان ( العكيلي، 2000، ص91).

يتسم القرن الحادي والعشرين بظاهرة العنف بشكل عام، حيث لم تسلم منطقة منه، وهذا لا يمثل تهديداً لمنجزات الانسان المادية والاجتماعية فقط، ولكنه يمتد نحو الانسان ذاته. وسلوك الع

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Publication Date
Tue Jan 01 2008
Journal Name
Journal Of Educational And Psychological Researches
مستويات التقويم والتصانيف التي تضمنتها في اسئلة امتحان مادة التاريخ
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      جاء التقويم  ليكون مكملا للعمليات التعليمية يساعد على الوقوف على نتائجها وسبل النهوض بها والوقوف على المعوقات التي تقف امام مسيرتها وقد عنيت عمليات التقويم باهتمام كبير من قبل القائمين على العمليات التعليمية اذ عقدت العديد من المؤتمرات والندوات واجريت العديد من الدراسات عالميا ومحليا من اجل الوقوف على هذه العملية المهمة الداعمة للتعليم والنهوض بمستويات المتعلمين ، ومن بي

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Publication Date
Wed May 03 2006
Journal Name
كلية اللغات \ جامعة بغداد
التطابق بين أجزاء الجملة في مسرحية الوصيفات لأنطونيو بويرو باييخو.
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التطابق بين أجزاء الجملة في مسرحية الوصيفات لأنطونيو بويرو باييخو.

Publication Date
Wed Dec 11 2019
Journal Name
Journal Of The College Of Education For Women
Differences of Style between English and Arabic Political Discourse: A Contrastive Study
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Traditionally, style is defined as the expressive, emotive or aesthetic emphasis added linguistically to the discourse with its meaning is the same. In the current study, however, style is defined as the linguistic choice that the language users can make for specific purposes.

    This study, thus, aims at analyzing political Arabic and English speeches to find out whether there are differences of style between English and Arabic and whether the choices the language users make  can show any traits of their psychological status.

    To fulfill the above aims, the study hypothesizes that English and Arabic  speeches can be analyzed stylistically and that there are stylistic difference

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Publication Date
Tue Mar 15 2022
Journal Name
Arab Science Heritage Journal
فاعليّةُ التعبير بالجناس الناقص في ديوان حازم القَرطاجنّي (ت 684هـ)
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This search aims to meditate Divan of Hazem Al-Qirtagni his incomplete contiguous and non-contiguous naturalizations are investigated through two interrelated sections, the first is contiguous deficient naturalization and the analysis of phonemic symmetry in the light of syntactic syntax, phonemic (partial) symmetry and semantic difference

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
العوامل المؤثرة في تخفیف الأعباء المنزلیة لدى المرأة العراقیة العاملة
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In the past, an absolute authority was held by the father and his decisions were imposed
and obeyed strictly without discussion. Later, many economical changes took place and
affected all of the family members dramatically creating a whole new concept of authority
in the family, a one that is based upon sound leadership, mutual understanding and
consultation among family members.
Women carried responsibility of doing all domestic jobs and served family members,
however, when she went to work outside her house, these loads began disturbing and
exhausting her. Therefore, man started to participate in assisting his wife. In addition,
industrial advances contributed in making these jobs easier than before.
This has

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