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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
Tue Sep 13 2022
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
اثر انموذج تسريع التعلم في تحصيل مادة الرياضياتوالتفكير المحوري لدى طالبات الصف الثالث المتوسط
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Publication Date
Thu Mar 30 2023
Journal Name
مجلة نسق
واقع التمكين الاداري في كلية التربية للعلوم الصرفة - ابن الهيثم من وجهة نظر موظفيها
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Publication Date
Tue Dec 22 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
التحول نحو أساس الإستحقاق المحاسبي لتعزيز المساءلة وإدارة الموجودات الثابتة للقطاع العام في العراق
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The research aims to present and discuss the accounting bases adopted in accounting for fixed assets in the public sector with an emphasis on its importance in the area of ​​accountability and fixed assets management , based on a realistic problem associated with the use of cash basis accounting in the public sector in Iraq, which are difficult  to provide accounting information useful for many users , including the same units and regulatory departments for the purposes of accountability and management of those assets. Search tool has been the organization questionnaire, its results show the importance of financial reporting for provide accounting information about fixed assets relate to the units of the public sector in Iraq fo

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Publication Date
Tue Dec 11 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Contribution of Some Managerial Accounting Techniques to Achieve Market Share Requirements / Applied researchin the Al-Muthanna Cement Company
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The research aims to achieve market share requirements and reach the targeted competitive price through the application of management accounting techniques represented by continuous improvement technique and target costing under an Activity Based Cost (ABC) system and Activity Based Management (ABM), In Muthanna Cement Company to reach the rationalization of the cost of the product and maintain the required quality and improve the profitability of the company.

The problem of research has emerged in the inability of local firms to enter into effective competition with other companies operating in the same economic sector, Because of the high cost of its products, Which led to the sale of the product at prices below its cost, and t

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Publication Date
Sun Apr 03 2011
Journal Name
Journal Of Educational And Psychological Researches
اثر الانموذج المعملي في تصحيح المفاهيم الرياضية شائعة الخطأ لدى طلاب الصف الاول المتوسط
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ملخص الدراسة
سعت الدراسة تعرف اثراستعمال الأنموذج المعملي في تصحيح المفاهيم الرياضية شائعة الخطأ لدى طلاب الصف الأول المتوسط بالإجابة عن السؤال "ما اثر استعمال الأنموذج المعملي في تصحيح المفاهيم الرياضية شائعة الخطأ لدى طلاب الصف الأول المتوسط" ولتحقيق هدف الدراسة وضعت الفرضية الصفرية "لايوجد فرق ذو دلالة إحصائية عند مستوى الدلالة (0.05) بين متوسطي درجات طلاب المجموعة التجريبية الذين يدرسون المادة المقرر

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Publication Date
Sun Jan 01 2017
Journal Name
Journal Of The College Of Languages (jcl)
Traducción de los dos verbos auxiliares ser y estar del español al árabe en la frase nominal
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Resumen:

       La traducción de los dos verbos ser y estar no es una tarea tan simple como piensan muchas personas, sino es una de las complicadas y difíciles tareas, ya que el traductor tiene que saber y perfeccionar los correctos casos gramaticales relacionados con esos dos verbos auxiliares  tanto el verbo ser como el verbo estar, especialmente en la frase nominal para que pueda dar una clara y correcta traducción. Usados con el mismo adjetivo, "ser" comunicará una cualidad que es parte de la identidad o naturaleza del sujeto, mientras que "estar" comunicará un estado o circunstancia del mismo. Este e

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Publication Date
Sun Feb 10 2019
Journal Name
Iraqi National Journal Of Nursing Specialties
Self-Esteem and its Relationship with the Age, Gender and academic Achievement among the students of the south Iraq Colleges of Nursing
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Abstract
Objectives: this study aims to: (1). Assess self-esteem level and academic achievement for students of nursing colleges in southern Iraq. (2). Determine the relationship between levels of self-esteem and academic achievement of the student in the first semester. (3). Identify differences of self-esteem with gender and different age groups.
Methodology: a sample of (426 students) was purposively selected then collected by using a questionnaire which consisted of: I- Sociodemographic characteristics for assessing some important aspects of students, II- Rosenberg's Self-Esteem Scale (RSES) III- Iraq Grading Scale for assessing student achievement. Finally statistical analysis (SPSS) for data processing.
Results: study resu

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Publication Date
Mon Oct 06 2014
Journal Name
Journal Of Educational And Psychological Researches
اثر برنامج أنشطة مكتبية لتنمية بعض القدرات الإبداعية في الأداء اللغوي عند اطفال الرياض
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This study aims to find out the impact of activities office provided to kindergarten children in the development of creativity in linguistic performance goal of capabilities (fluency, flexibility and originality) through the application of the test configuration Algheih Children Riyadh, which consists of (70) Single to measure the skills of language arts four a listening and speaking and a willingness to read and prepare for writing, was applied (30) Single of language arts, listening and speaking in this research, and was the correlation coefficient for the hearing (0.78) and for speaking was (0.61) has been extracted stability of the scale using the equation Alvakronbach the value of (0.73).

The proper

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Publication Date
Thu Jan 31 2019
Journal Name
Journal Of The College Of Education For Women
Geomorphological Phenomena of the Tigris River between Dojama and Sindia Villages, Al Khalis District, Diyala Province
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Differences in transversal sections and activities of geomorphological operations led to forming geomorphological shapes as river turns and river isles in watercourse in the area of study. The study showed three river turns that are Sindia turn with length 4723m, turn wave 3599 average width 267.6, Zanbour turn length 11374m, turn wave 7110 average width 307.5m,and Dojama turn with length 5876m, turn wave 4982m average width 313.4m. This difference is caused by the activity of erosion and sedimentation that led to the appearance of the length rivers turn.
The study showed that the turn of Dojama is the only corresponding turn, whereas the phenomena of corresponding never appeared in other turns in the area of study. The study also sho

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Publication Date
Sun Apr 03 2011
Journal Name
Journal Of Educational And Psychological Researches
أثر التدريس بطريقة التنقيب الحواري في حفظ النصوص الأدبية لدى طلبة قسم اللغة الكردية
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يهدف البحث الحالي إلى معرفة اثر التدريس بطريقة التنقيب الحواري في حفظ النصوص الأدبية لدى طلبة قسم اللغة الكردية، اختارت الباحثة طلبة المرحلة الثانية في قسم اللغة الكردية بكلية التربية ابن رشد، للعام الدراسي
(2008-2009) ميدان لتطبيق تجربتها.
تألفت عينة الدراسة من (48) طالبا وطالبة، تم توزيعها عشوائيا إلى مجموعتين، مجموعة ضابطة (درست بالطريقة الاعتيادية) تألفت من (23) طالبا وطالبة ومجموعة تجريبية (درست بطريقة الت

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