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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
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
تقويم جودة مهارات التدريس لدى مدرسي الرياضيات في المرحلة الإعدادية الفرع العلمي من وجهة نظرهم
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   Research aims at evaluating the quality of the teaching skills of math teachers in junior high / scientific branch  from their point of view.

The researchers prepared for this purpose a quality of teaching skills standards questionnaire, It consisted of 72 items distributed on four axis, The research sample was 200 teachers The researchers used statistical methods: the arithmetic mean, standard deviation, variance test, test Shiva  , The results showed a statistically significance difference Attributed to the qualification  variable  in the second  axis (Planning for teaching topics) And the absence of statistical difference function,

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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
Sun Feb 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Reliability Estimation Of Fuzzy Failure Times Of Free Distribution And It Use To Estimate The Fuzzy Reliability Of Mosul Dam
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The way used to estimate the fuzzy reliability differs according to the nature of the information of failure time which has been dealt in this research.The information of failure times has no probable distribution to explain it , in addition it has fuzzy quality.The research includes fuzzy reliability estimation of three periods ,the first one from 1986 to 2013,the second one from 2013 to 2033 while the third one from 2033 to 2066 .Four failure time have been chosen to identify the membership function of fuzzy trapezoid represented in the pervious years after taking in consideration the estimation of most researchers, proffional    geologists and the technician who is incharge of maintaining of Mosul Dam project. B

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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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Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
استعمال أنموذج (Altman) للإفلاس دالة لقياس الأداء دراسة تطبيقية في بعض الشركات المساهمة الخاصة العراقية
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Performance measures are a central component of management control system, making good planning and control decisions requires information about how different subunits of organizations have performed. To be effective, performance measures (both financial and nonfinancial) must also motivate managers and employees at all levels of organization to strive to achieve organization goals.

To give aclear picture about performance must be used compound measure, that was best than single measure.

Altman model can be used as a compound performance measure that measures the performance by tied a sum of variables, due to make weight for every variable to reach for performance.

 

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Publication Date
Fri Sep 25 2026
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 Jul 03 2016
Journal Name
Journal Of Educational And Psychological Researches
الارهاب وتداعياتة على الامن والسلم الاجتماعي (دراسة ميدانية للعوائل المتضررة من الارهاب في مدينة بغداد )
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     تعد ظاهرة الارهاب المتزايدة في العالم من اخطر اشكال التهديدات الامنية التي تواجة الدول لانها تستهدف في جانب مهم منها امن واستقرارومستقبل مجتمعاتها لاسيما اذا جمع الفعل الارهابي بين مطامع واهداف القوى الخارجية التي لا تريد استخدام ادواتها المباشرة وانما بالاعتماد على                   محركات في خلق الازمات داخل الدول المستهدفة

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Publication Date
Sun Oct 04 2009
Journal Name
Journal Of Educational And Psychological Researches
أثر إستراتيجية الملخصات القبلية على التحصيل الدراسي لطالبات الصف الثالث المتوسط في مادة التربية الأسرية
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لقد أدت التطورات العلمية والتقنية وتطبيقاتها العملية في مختلف ميادين الحياة بشكل عام وميدان التربية والتعليم بشكل خاص إلى ظهور تغيرات في البناء التعليمي وطرائق التدريس بصيغتها الحديثة التي تنسجم في مجملها وروح العصر مما دعى المؤسسات التربوية والتعليمية وبإيعاز إلى الباحثين والمهتمين بهذا الميدان الى ضرورة متابعة الاتجاهات الحديثة ونواحي التجديد لمحتوى العملية التعليمية فيما يتعلق بالمجالات المعر

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Publication Date
Mon Jun 01 2015
Journal Name
Journal Of The College Of Languages (jcl)
ES’AT NAİB’İN “ZAMANIN ELİ” ADLI DİVANINDA İSİM ÇEKİM EKLERİ (Karşılaştırmalı İnceleme)
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Irak Türk ağızları Azeri Türkçesinin bir uzantısı olarak değerlendirilir.Kerkük Türkçesiyle yazılan edebi ürünler, Irak Türkçesinin tamamını ifade etmek üzere kullanılmaktadır. Zamanın Eli divanı Kerkük Türkçesile yazılan bir eserdir. Bu yüzden bu divanı seçtik ve Irak Türkmen Türkçesi , Osmanlı Türkçesi ve Türkiye Türkçesi dilleri arasında  karşılaştırmalı bir inceleme yaptık.

Bu araştırma, Irak Türkmen şairlerinden birisi  sayılan  Es’at Naib’in  şiirleri üzerinde uygulamalı bir çalışmadanoluşmaktadır. Bu çalışmada adı geçen şairin “Zamanın Eli” Divanından bazışiirlerini önce yeni Türkçeye çevirdik vedaha sonra isim ç

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Publication Date
Tue Feb 02 2021
Journal Name
مجلة بحوث الشرق الأوسط
المشارکات النسوية العراقية بألعاب القوى في الدورات العربية للفترة من 1948م ولغاية 2017م والنتائج المتحققة
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تناول هذا البحث عرض وتوثيق المشارکات النسوية العراقية بألعاب القوى في الدورات الرياضية العربية منذ تأسيس اتحاد ألعاب القوى عام 1948م ولغاية عام 2017 م، وکذلک تحليل النتائج المتحققة لهذه المشارکات ومناقش أسباب عدم المشارکة في بعض هذه الدورات ومحاولة الباحثات أن يبينن الدور المتميز للرياضيات العراقيات أسوة بنساء الوطن العربي وإسهامهن الفعال في هذه الدورات من أجل تمثيل، البلد خير تمثيل، وکذلک النهوض بالواقع الر

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