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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
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
Tue Oct 08 2002
Journal Name
Iraqi Journal Of Laser
Spatial Response Uniformity of Silicon–Based CdS and PbS Heterojunction Laser Detectors
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This paper demonstrates the spatial response uniformity (SRU) of two types of heterojunctions (CdS, PbS /Si) laser detectors. The spatial response nonuniformity of these heterojunctions is not significant and it is negligible in comparison with p+- n silicon photodiode. Experimental results show that the uniformity of CdS /Si is better than that of PbS /Si heterojunction

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Publication Date
Sun Apr 28 2019
Journal Name
Arab Science Heritage Journal
الظواهر الظواهر الاجتماعية في بغداد من خلال كتاب الظرف والظرفاء لابي الطيب الوشاء(ت320هـ)
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 the study of social phenomena in this direction is, the sign of deviousness to the segments of the circumstance with their conditions and circumstances, then pointed to the uniforms that they were adorned by the tortillas as well as shirt Safaf from good linen soft and touched the country and the good and others.

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Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
The Effect of MHD on a Longitudinal Flow of a Fractional Maxwell Fluid between Two Coaxial Cylinders
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      In this paper fractional Maxwell fluid equation has been solved. The solution is in the Mettag-Leffler form. For  the corresponding solutions for ordinary Maxwell fluid are obtained as limiting case of general solutions. Finally, the effects of different parameters on the velocity and shear stress profile are analyzed through plotting the velocity and shear stress profile.

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Publication Date
Sat Sep 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
صياغة أهداف المحاسبة والتقارير المالية في ظل اختلاف المتغيرات البيئية أفكار مطروحة وأراء مقترحة
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المقدمة ومنهجية البحث

تتفق أغلب الأدبيات ومنها المحاسبية, بأن الخطوة الأولى في وضع وتقييم أي نظام إداري أو محاسبي هي في صياغة أهداف ذلك النظام لما لذلك من أهمية في توفير معيار للحكم على كفاءة التطبيق من عدمه.

وتعرف الأهداف بأنها (النهايات التي تعمل أو توجه النشاطات باتجاهها أو هي النهايات التي تطمح النشاطات تحقيقها). ( 1 ) ..,

 كما تعرف أيضا بأنها (الأ

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Publication Date
Fri Oct 28 2022
Journal Name
Political Sciences Journal
The Difficulties of Teaching Political Science Research Methods: A Comparative Study between Western and Arab Universities
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This research aims to identify the reality of teaching political science research methods curriculum, to observe practices, and differences in teaching and learning between the Arab and Western universities. Moreover, it focuses on the difficulties that face students' acquisition of the course skills. The research uses the course model of some Western and Arab universities as case study.

This research shows that the curriculum do not reach yet the final form as other political science curriculums, and its upcoming changes will reflect the needs of stakeholders. The best method to teach this curriculum is to use applied learning in groups, learning by doing, and finally problem-based learning approach. Using optimal assessment deep

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Publication Date
Fri Dec 01 2023
Journal Name
Political Sciences Journal
Exploring the Effects of European Union Conditionality Language on European Mediterranean Human Rights Dialogue
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Since more than a decade, human rights dialogue in the European Mediterranean Region has been marked by a number of tensions. Although a number of factors contribute to such disputes, the effect of human rights conditionality, which ties EU economic cooperation progression with partner countries human rights advancement, on the dialogue has not been studied. Understanding the aspects, impacts, and effects of conditionality on Euro-Med relations is crucial for furthering dialogue. Yet this variable has been almost entirely neglected in academic and policy research. The research concludes several direct and indirect impacts of conditionality on human rights dialogue using a mixed methodology approach. Direct effects are reflected in the wi

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Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
The Degree of the E-Leadership Practice at Princess Nora Bint Abdul Rahman University of the Corona Pandemic
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The study aimed to identify the E-leadership practice at Princess Nora Bint Abdul Rahman University and to explore the obstacles that are facing the leaders in the implementation of E-leadership, in addition to find mechanisms to improve the practice of electronic driving at the university in light of the Corona pandemic. A descriptive analytical approach was used by depending on a questionnaire to collect the needed data. The study sample consisted of (139) heads of departments, attorneys' colleges and support Deanships universities. The study results showed that E-leadership employment recorded a medium to high degree. Especially at university, that publishing decisions electronically and uses technical means in providing its services.

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Publication Date
Fri Nov 11 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The initiative of the Central Bank of Iraq and its impact on some banking activities provided by private Islamic banks
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Islamic banks are distinguished by providing banking activities that are unique in providing them from the rest of the other types of banks, and these activities are a group of banking services provided by the bank to its customers, whether these banking activities are tangible or intangible. At the same time, it is a source of bank profits, as Islamic banks impose a percentage of Islamic Murabaha on those banking activities , However, these banks have developed new services that they provide with the funds of the Central Bank initiative launched at the beginning of (2016) due to the economic conditions that befell the country due to the (financial security) crisis that the country faced in 2014. To put forward initiatives, and a

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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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