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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 Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
اثر استخدام دورة التعلم في تحصیل طالبات مرحلة الرابع العام للمعلومات الفیزیائیة واستبقائھا
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This research aims to reveal the impact of applying a teaching course in
gaining and preserving information by female students comparing with the
traditional method, through testing the two following hypotheses:
1. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the control group of female students taught using the traditional
method.
2. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the contro

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Publication Date
Sat Jul 01 2017
Journal Name
Al–bahith Al–a'alami
The effects of Internet use on university’s students: “A Study on a Sample of Jordanian University’s students "
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The effects of Internet use on university’s students:The effects of Internet use on university’s students:“A Study on a Sample of Jordanian University’s students "This survey aims to identify the most important effects of Internet use on Jordanian public and private universities’ students by monitoring and analyzing a set of indicators that show the quality of the effects on specific fields such as  cultural, social, psychological, moral and political effects .To achieve these goals, the study attempts to answer the following questions:1.   What are the effects of Internet’s use on students?2. What is   the relationship between the effects and demographic variables such as  gender, age, family size an

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Publication Date
Sun Mar 15 2020
Journal Name
Journal Of The College Of Education For Women
Rhetoric Effect of Ibn Al Faridh’s Poetry Counterparts: اسماء خليل ابراهيم, فرج منسي محمد
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 The Sufi poetry of Ibn Al-Faridh represents a true image of the spiritual  experience, in which he presented the bright aspects of  his experience, and his suffering in it, by formulating it in a poetic form, because the Sufi poetry is the result of an experience in which the Sufi seeks to achieve his goal of reaching the truth, and this is why Ibn Al-Faridh made his poetry a tool for expression on his own experience, the poet reflected his Sufi life in which he moved rhymes and weights.

   The poet Ibn Al-Faridh stands as a witness to his making of  Sufi poetry in the service of the purpose of who said, it is the embodiment of the Sufi journey in the stages, and the fluctuation in the places and si

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Publication Date
Sun Jul 02 2006
Journal Name
Political Sciences Journal
واقع الدراسات الاورومتوستطية في الجامعات العراقية "دراسة حالة كلية العلوم السياسية - جامعة بغداد"
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واقع الدراسات الاورومتوستطية في الجامعات العراقية "دراسة حالة كلية العلوم السياسية - جامعة بغداد"

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Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
نظام الكوتا النسوية بوصفه مدخلاً لبناء المجتمع العادل : دراسة في تمكين المرأة الكوردستانية
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It could be said that the essence of the “quota” is the state’s intervene as external power in bringing positive change for the benefit of the disadvantaged women and cultural minorities, and from the perspective that compensatory justice requires dealing differently with the different parties culturally and economically for the benefit of those deprived of them. Practicing of quotas merely, does not mean the full achievement of equality between cultural and sexual components in general, but it’s a big leap towards achieving this crucial goal, since the latter necessarily requires a range of legal and non-legal mechanisms aimed at empowering women and expanding their capabilities as a whole. On the other hand, in the absence of a

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
أثر برنامج التعبئة النفسية في مواجهة أحداث الحياة الضاغطة لدى طلاب المرحلة الاعدادية
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The Stressful Life Events consider one of the important thing in humans life in different period of life even school period,   where it is deal with vital period of life which is the youth period that represent the hope and precious resources that nation depend on it in building her civilization, structure anddevelopment  ,they are part from the present and whole future .As the great effect of stressful life event on humans , increase the need to put a program about psyching-up which consider one of the modren and effective programs.The aim of current search:1.   Measure the level of stressful events at the junior high school  studen

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Publication Date
Sun Apr 06 2014
Journal Name
Journal Of Educational And Psychological Researches
مراكز التعليم ودورها التربوي في حركة التدريسينفي العصر العباسي الأخير (447-656 ﻫ)
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لم يكن من السهولة على الباحث في مجال التربية والتعليم تحديد مراحل التعليم في العصر العباسي الأخير او وضع فواصل محددة بين تلك المراحل المختلفة من ذلك العصر، لان التعليم آنذاك كان يتميز بالمرونة التي تتيح للتعليم الحرية المطلقة في اختيار نوع الدراسة والمادة الدراسية التي يريد دراستها.

فكانت المساجد والكتاتيب والمجالس العامة والخاصة هي المؤسسات العلمية الاولى للتعليم عند المسلمين في عهد ال

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Publication Date
Sat Jun 01 2024
Journal Name
مجلة الدراسات المستدامة
المسؤولية المدنية الناشئة عن الاخلال بالالتزام بضمان سلامة الاشخاص في عقد التحاليل الطبية
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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Competitiveness of an enterprise under a flexible manufacturing system. Manufacturing strategy and flexibility - Case study
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The research has designed for studying the relationship between manufacturing strategy and its flexibility under the flexible manufacturing system with their reflection on the competitive environmental performance of the firm. To interpret and tackle the problem, a hypothesis has formulated stating that “ the competitive performance of a firm is interpreted by the manufacturing strategy and flexibility which are derived from the firm and its business  strategies under the flexible manufacturing system”. Related literatures with their theoretical dissertations, which enhanced the thoughtful content, have analyzed. An illustrative case study on the flexible manufacturing system at Toyota Motors Corporation working at the g

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Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
التكيف للحياة الجامعية وعلاقته بالصف الدراسي لدى طالبات الاقسام الداخلية في الجامعة المستنصرية
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يواجه الكثير من الافراد مشكلات في التكيف، خاصة الطلبة الذين ينتقلون من المرحلة الدراسية الثانوية الى المرحلة الجامعية، حيث يرافق هذه البيئة الثقافية الاجتماعية العديد من الضغوط والمواقف التي تحتم على الطالب الوصول الى تكيف مثالي.

ان التعليم الجامعي يوفر مجالات عديدة للتخصص تعمل على تحقيق طموحات الشباب التي تناسب قدراتهم وميولهم واهتماماتهم، وهو بذلك يمثل نوعية من التعليم تختلف عن النم

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