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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
Thu Sep 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقييم الأداء المالي لشركات التأمين باستعمال النسب المالية: دراسة حالة في الشركة الجزائرية للتأمين
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Les sociétés d’assurances sont considérées parmi les importantes entreprises financières non bancaires.

      Pour que ces sociétés assurent sa continuité d’existence, il faut qu’elles veillent au rendement financier qui représente ses différentes actions durant une période déterminée, en effectuant une évaluation permanente en utilisant de différentes méthodes parmi lesquelles l’analyse financière avec ses aspects divers.

         L’objectif de cette étude est d’évaluer le rendement financier des sociétés d’assurances et où projette l’étude sur la société Algérienne d’assurance durant la période 07- 09.

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Publication Date
Sun Apr 03 2016
Journal Name
Journal Of Educational And Psychological Researches
The Impact of Cooperative Training of EFL Student Teachers on their Teaching Performance and Attitude toward Teaching
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Iraqi EFL college instructors, who supervise the teaching practice of EFL student teachers, commonly experience the inefficient teaching performance of prospective teachers. This inefficiency is usually due to their inability to make connections between the practical experience and the theoretical knowledge of TEFL. One of the reasons behind this inability may be the employment of traditional ways of training and instructing student teachers. Moreover, it is usually noticed that many Iraqi EFL student teachers have a negative attitude toward the teaching profession. They explicitly state that they would join the teaching force only if they fail to work in any other field.

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Publication Date
Wed Jul 01 2015
Journal Name
Journal Of Educational And Psychological Researches
مستوى التنمية المهنية لتدريسيي جامعة بغداد في ضوء مؤشرات الجودة الشاملة من وجهة نظرهم
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The present study aimed to know The teaching members’ level of the professional development at the University of Baghdad based on the indicators of the overall quality from their perspective;

The researchers used the descriptive and analytical approach the in order to achieve the purposes of research, the researchers designed questionnaire researched and consisted of 40 paragraph has the questionnaire submitted to the arbitrators and experts were verify the authenticity of the questionnaire and stability have been applied questionnaire on a range of teaching and Tdriciat Baghdad University, which reached the study sample (400) teaching and teaching of six colleges in the University of Baghdad equivalent

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Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Numbered Heads Strategy on Developing Oral Expression Skills among Fifth-Grade Primary Students
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This research aims to identify the effect of numbered heads strategy on developing oral expression skills among fifth-grade primary students in Bisha Province. To achieve this, the researcher prepared a research tool represented in the observation card which consists of (27) statements distributed in four axes. The tool was sent to (5) experts in the field to verify their validity. In light of their corrections, the tool was developed to be valid for gathering field information. To verify the validity of the content and the reliability of the tool, the researcher applied it to a sample consists of (20) students from outside the research group. The overall coefficient of correlation between the statements of the tool is as follows: (.95,

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Publication Date
Wed Oct 01 2008
Journal Name
Journal Of Educational And Psychological Researches
الضغوط النفسية والعوامل الاجتماعية المؤدية إلى الإصابة بأمراض القولون ( بحث ميداني في مدينة بغداد )
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بالنظر الظروف الراهنة التي يمر بها قطرنا ونتيجة للارتفاع معدل الاصابة بالامراض ذات الطابع النفسي جسمي او ما تعرف بامراض سوء التكيف الناتج عن الضغوط النفسية المستمرة.

ارتأت الحاجة الى دراسة هذا النوع من المرض والتي ترجعها الباحثة الى الاسباب التالية :.

1-تعرض المواطن العراقي الى ضغوط نفسية مستمرة متمثلة بحالة الانفلات الامني والشعور بالقلق المستمر المراف

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Publication Date
Fri Jun 01 2007
Journal Name
Journal Of The College Of Languages (jcl)
Molla Mehmet Sadık'ın Kerkük'teki Eskide Bulunan Taş Köprü Adlı El Yazısının İncelemesi Açıklaması
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Yaşıyan kuşağın unutulmaz aruz şairi tanınmış Hacı Mehmet Sadık. İzi
silinmez kaybin, bugünkü eski sitil şiirin gerçek sembolu olup yaşadığı bir çağa
yakın süre içinde yüzlerce ve yüzlerce beyit şiir söylemiş.
Her çevrede Türk doğup Türk yaşamak bahtıyarliğiyle övünen ozanımızın ,
seçkin bir çok şiirleri vardır.
Böylece kitap, dergi ve gazetelerde yayımlanmış sayısız şiirleri yanında
basıma hazır kitaplık şiir ve yazılarıda vardı. Gazetelerde yayımlanan şiirlerini
memleket dertlerine , değerli mert kişilerine gönüllerde yaşıyan ölülerine , yurdu
ve yurttaşı için iyilik güden devlet ve memleket büyüklerine ayırdığını
görmekteyiz.<

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Publication Date
Wed Dec 01 2021
Journal Name
Baghdad Science Journal
Enhancement of Electron Temperature under Dense Homogenous Plasma by Pulsed Laser Beam
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The applications of hot plasma are many and numerous applications require high values of the temperature of the electrons within the plasma region. Improving electron temperature values is one of the important processes for using this specification in plasma for being adopted in several modern applications such as nuclear fusion, plating operations and in industrial applications. In this work, theoretical computations were performed to enhance electron temperature under dense homogeneous plasma. The effect of   power and duration time of pulsed Nd:YAG laser   was studied on the heating of   plasmas  by inverse bremsstrahlung  for  several values for the electron density ratio. There results for these ca

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Publication Date
Sun Apr 01 2007
Journal Name
Journal Of Educational And Psychological Researches
القدرة على القيادة التربوية وعلاقتها بالاتجاه العلمي لدى رؤساء الاقسام في بعض الجامعات العراقية
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مشكلة البحث :

تعد الادارة الجامعية عاملا مهما واساسيا في اكمال البناء المعرفي لشخصية الطالب الجامعي لما يمثله من قدرة على قيادة العملية التربوية والتعليمية والوصول بها الى تحقيق اهدافها . وطالما كانت هذه الادارة ممثلة ابتداء من رئاسات الاقسام ووصولا الى اعلى الهرم الاداري في الجامعة مهمة في تحقيق  الاهداف العلمية والتربوية فان اختيار الاشخاص للقيام بمهامها تاخذ جانبا كبيرا ومهما وذلك للاثر

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Publication Date
Fri Jan 01 2016
Journal Name
مجلة جامعة كربالء العلمية
دراسة شكليائية ونسجية للكلية في الساحف )أبو بريص( وزغة خشنة الحراشف Cyrtopodion scabrum (Heyden, 1827)
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Publication Date
Sun Aug 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Effect of leadership patterns on the phenomenon of jop burnout among employees at Baghdad College of Economic Sciences University
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This study deals with the impact of leadership styles in its three main dimensions (democratic, autocratic, lenient) as an independent variable of the dimensions of functional combustion (emotional stress, inhumanity, personal achievement). The research sought to achieve a set of goals, the most prominent of which are: studying the reality of the researched organization to identify the leadership patterns used in its management and its impact on the phenomenon of functional combustion, Moreover, knowing the extent of support for these established patterns and their contribution to mitigating the phenomenon of functional combustion in the organization's environment, and testing the impact of these leadership patte

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