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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 Dec 26 2022
Journal Name
Arab Science Heritage Journal
قيود الختام او حرود المتن دراسة تطبيقية بالاستناد على نماذج مختارة من المخطوطات الاسلامية من القرن(10-13هـ/ 16-19م) في المكتبة المركزية بأربيل:
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     Islamic manuscripts are considered an identity for the civilizational, cognitive and cultural development of nations and the Islamic world as a whole, and to identify this identity, the closing statement usually written at the end of the manuscript helps us with this, meaning that the closing entries serve as the identity document of the manuscript

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Publication Date
Tue Dec 31 2019
Journal Name
Arab Science Heritage Journal
جهود جُهُودُ عُلَمَاءِ العِرَاقِ في تَدْوِينِ الف هَ ا رِسِ والكَ ش ا فَاتِ والمَ جَ ل تِ المعْ ن يةِ بال ت راثِ
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The scholars of Iraq in the modern and contemporary era have been interested in the definition of tremendous knowledge treasures left by the successive Iraqi civilizations on Mesopotamia and around the cities, through the census and extrapolation of manuscript heritage and even printed, they compiled indexes,evidence

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Publication Date
Wed Jul 07 2021
Journal Name
جهاز التقيسس والسيطرة النوعية
تحضيروتشخيص ودراسة طيفية وحرارية وبيولوجية للمركب الجديد والمشتق من 2-امينوبينزوثايوزول واستخدامه كمثبط لتأكل سبيكة (-brass) في أنابيب مياه الشرب مع بعض المعقدات الفلزية
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تحضيروتشخيص ودراسة طيفية وحرارية وبيولوجية للمركب الجديد والمشتق من 2-امينوبينزوثايوزول واستخدامه كمثبط لتأكل سبيكة (-brass) في أنابيب مياه الشرب مع بعض المعقدات الفلزية

Publication Date
Thu Sep 15 2022
Journal Name
Alustath Journal For Human And Social Sciences
کاریگەری ستراتیجیەتی مێزگرد لەسەر دەستکەوتی بابەتی خوێندنەوە و ئەدەبی کوردی
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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
دراسة حالة: Case Study
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The purpose of this research is to demonstrate the impact of deposit insurance to reduce banking risks, as banks in various countries of the world face a variety of risks that led to banking and financial crises that led to the failure and bankruptcy of many of its bank, which led to the banks to find quick and appropriate solutions to get rid of these difficulties These solutions include the use of bank deposit protection system for the many risks and sequences of crises that accompanied the Iraqi banking work of thefts, forgery, embezzlement and changing and unstable circumstances. The importance of studying the subject of research through the theoretical framework of banking risks as well as the framework of consideration In order to

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Publication Date
Wed Dec 28 2022
Journal Name
مجلة التربية الرياضية
إدارة درس التربية الرياضية لدى الطالب المطبق وفقا المهارات التدريسية من وجهة ً الهم نظر اعضاء هيأة التدريس في كلية التربية البدنية وعلوم الرياضة جامعة بغداد
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Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
الإدراك الحسي الحركي لدى الطلبة المتفوقين والمتأخرين دراسيا في المدارس الإعدادية (بحث مستل من رسالة ماجستير بنفس العنوان / جامعة بغداد) كلية التربية للبنات 2009 م
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مشكلة البحث   The Problem of the Research

 

          يعّد التحصيل الدراسي للطلبة عموما من أهم أركان النشاط العقلي في المجال التربوي، فلا تكاد تخلو منه أيه مدرسة، أبتداءً من المدارس الابتدائية وقد تسبقها رياض الأطفال، إلى المدرسة الإعدادية والجامعية ، وقد تمتد إلى مراحل متقدمة في العمر، فكان الطالب وما يزال هو محور العملية ال

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Publication Date
Sat Apr 01 2017
Journal Name
مجلة العلوم الاحصائية
نمذجة السلاسل الزمنية التي تنتجها اجهزة الاحصاء الدولية وانتاج قيم تنبؤية لمتخذ القرار حالة دراسية : التنبؤ بالمساحة المزروعة لمحصول الذرة الصفراء في العراق للفترة (2015-2020
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تنفذ أجهزة اإلحصاء الدولية ومنها الجهاز المركزي لإلحصاء في العراقإحدى أجهزة وزارة التخطيط، تقوم بإجراء مسوح سنوية ودورية لإنتاج مؤشرات تقييم وتقويم أنشطة القطاعات الاقتصادية المختلفة. يتيح هذا الكم الهائل من البيانات بشكل سلسل زمني لهذه الأجهزة إنتاج مؤشرات جديدة، بما في ذلك القيم التنبؤية لمؤشرات رئيسية تستخدم في إعداد الخطط طويلة وقصيرة المدى. في عام 2015، قامت مديرية الإحصاء الزراعي في الجهاز المركزي للإ

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Publication Date
Sun Apr 10 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
أثر خصائص لجنة التدقيق في الإفصاح عن رأس المال الفكري: أدلة من فسطين: The Impact of Audit committee characteristics on Intellectual capital disclosure : Empirical evidence from Palestine
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The study aimed to examine the impact of audit committee characteristics on the practices of intellectual capital disclosure in the annual reports of Bank and Insurance companies listed on Palestine Exchange, through performing content analysis of the annual reports for the study sample which totaled thirteen companies, including six banks and seven insurance companies. To achieve the study objectives, the study employed a content analysis approach in order to analyze the content of the intellectual capital disclosure practice, in addition, the study used cross-sectional with longitudinal data for time series for a period of time between 2014-2019. The empirical results indicated that financial expertise and the number of meeting

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Publication Date
Tue Dec 22 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
المسار النموذجي لتدقيق اداء الدور الاشرافي للبنك المركزي العراقي على المصارف الخاصة على وفق معايير الاجهزة العليا للرقابة المالية والمحاسبة: بحث تطبيقي في ديوان الرقابة المالية الاتحادي
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With today's rapid and full of dangers the world banking sector is one of the most vital sectors at risk, and on the supervisory bodies responsible for monitoring the work of banks to take an active role in influencing the banks and put on the right track and is compatible with internationally approved curriculum. The lie of the research problem in the weak supervisory role of the Central Bank for banks in general and private banks in particular, limited the process of performance audit carried out by the Federal Office of Financial Supervision in auditing oversight role of the Central Bank control over the banks, according to the methods of performance audit followed by the upper bodies of financial control and accounting, And it was ba

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