Preferred Language
Articles
/
alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
...Show More Authors

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%.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Feb 01 2021
Journal Name
مجلة كلية التربية للعلوم الانسانية
الاوهام الايجابية لدى طالبات الجامعة في ضوء بعض المتغيرات
...Show More Authors

وهدف البحث إلى التعرف على الاوهام الايجابية فضلاً عن التعرف على الفروق في الاوهام الايجابية بين الطالبات على وفق متغير الحالة الاجتماعية (متزوجة – غير متزوجة) والتخصص الدراسي (علمي – انساني) والمرحلة الدراسية (اول- رابع)، تألفت عينة البحث من (120) طالبة من طالبات جامعة بغداد -كلية التربية للبنات وكلية العلوم للبنات، وتم تطبيق مقياس البحث - مقياس (الاوهام الايجابية) وهو (من إعداد الباحثة)، وقد اسفرت نتائج البحث عن:

... Show More
View Publication Preview PDF
Publication Date
Wed Nov 14 2018
Journal Name
Arab Science Heritage Journal
الامام الإمام الطرطوشي (520هـ) وآراؤه الفقهية في الأحوال الشخصية
...Show More Authors

This research deals with the ideas of Imam Muhammad bin Al-Waleed bin Khalaf bin Sulaiman bin Ayyub , Al -Qurashi, The Moroccan, The  Andalusian, Al-Maliki. He was  known as Abu Bakr Al-Tartoushey , where thesis deals  with the details of his personal life and as well as his scientific path  as well as  his works, and also covered the views of jurisprudence in the personal status and especially on the subject of divorce and inheritance,

View Publication Preview PDF
Publication Date
Mon Sep 30 2024
Journal Name
مجلة نسق
بعض اللفظات في صور القران الكريم لفظة اكل انموذجا
...Show More Authors

ان الداسات القرانية تعد من الدراسات المتعلقة في اللغة العربية لانها تتعلق بدراسة جانب من جوانب اعجاز القرأن الكريم لذلك قمت بدراسة جانب من جوانب اعجاز القران الا وهي لفظة اكل

Publication Date
Sun Mar 01 2009
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
مسؤولية مراقب الحسابات في تقويم مخاطر المشروعات الصغيرة والمتوسطة
...Show More Authors

There are many characters which belong to small & medium projects, this is not relate to their size only but also to its quality charchcters & the quantities indicators.

There is a focus in the ownership, management, Resources beside the limited internal control system.

 the auditor must put his program according to the project’s circumstance, so auditing the small projects differs than other projects which maybe is less complex and done by limited persons

This research aims to show the responsibility of certified public accountant in evaluation the risks of the small & medium projects through depending the audit- based risk program which develop the useful information.

View Publication Preview PDF
Publication Date
Sun Nov 15 2015
Journal Name
مجلة دراسات ادارية
‫بواعث الفساد وتقنيات مواجهته في المؤسسات العامة - العلاقة والأثر
...Show More Authors

كان الفساد وما زال أحد المواضيع الرئيسة التي شغلت اهتمام الباحثين والدارسين في المجالات المعرفية المختلفة بضمنها المجال الإداري نظراً للتأثير السلبي والمباشر لإدارات المؤسسات الحكومية العامة على نجاح برامج وخطط التنمية في تحقيق أهدافها المجتمعية, إذ أن عملية تنفيذ هذه البرامج تقع على عاتق إدارات هذه المؤسسات في إطار التزام العاملين فيها بتحقيق الأهداف والسياسات التنموية العامة للدولة ، وحرصهم على تلبية ا

... Show More
Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
الألفاظ المَعبِّرة عن المطر في القرآن الكریم دراسة دلالیة
...Show More Authors

The Holy Koran is the highest text in the eloquence, It is one of the
important sources of the linguistic syntactic and eloquent study; it impacts
upon these sciences Avery intense impact through advancing its verses as an
argument in the confirmation of the significance of the term
The holy Koran was and still the fountain of the linguistic studies, as
they tend towards it since the second century of the hegira. So this research is
a study of the expressive terms concerning the rain in the holly Koran, a
linguistic study; it aims to study the term concerning its linguistic and
conjugate significance and its expression concerning the rain through reality
and metaphor.

View Publication Preview PDF
Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
إدراك الأزیاء في ظل علاقاتھا الجمالیة بعناصر العرض المسرحي
...Show More Authors

The fashion accused important optical avenge with the rest of visual elements
, That style of fashion design stir up beautiful feelings by using fashion forming
that is suitable with the nature of designable treatments to other elements .
The fashions contains the nature of relation ships of educational address and
the kind of beliefs , So the visual beauty is limited for those relation which are the
designer fashion tried to redesign and set them anew . so as to goes with beautifully
with the last visual for fashions.

View Publication Preview PDF
Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
pH-Control Problems of Wastewater Treatment Plants
...Show More Authors

Experimental investigations have been carried out to investigate the pH-control problems of industrial electroplating wastewater treatment plants. The accurate and sensitive PID control system could treat most problem and disturbances in the normal operation of the water treatment. However, conventional treatment was replaced by proprietary treatment agent called a QUASIL which was found to be more effective for a wide range of pH.

View Publication Preview PDF
Publication Date
Sun Sep 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The role of competitive intelligence and reverse engineering to achieve competitive advantage
...Show More Authors

Abstract

In light of the great technological development and the emergence of globalization has increased global competition, where it became competitive exercise pressure on all sectors. In light of this companies mast enviorment depend on the means that keeps them on the competitive position through access to information about competitors in order to help them to draw a strategy that will achieve a competitive edge either through excellence or reduce the costs of their products and this means intelligence competitive and reverse engineering that help to gain information on competitors analyze and put of the decision-maker From this point formed the idea of ​​research in the statement of the role of

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 28 2021
Journal Name
مجلة علوم الانسان والمجتمع
اصالة الذات لدى طلبة الجامعة في ضوء بعض المتغيرات
...Show More Authors

هدف البحث إلى التعرف على اصالة الذات فضلاً عن التعرف على الفروق في اصالة الذات بين الطلبة على وفق متغير الجنس (ذكر – انثى) والتخصص الدراسي (علمي – انساني) والمرحلة الدراسية (أول- رابع)، تألفت عينة البحث من (140) طالبا وطالبة من طلبة جامعة الموصل-كلية التربية الاساسية، وتم تطبيق مقياس البحث - مقياس (اصالة الذات) وهو (من إعداد الباحثة)، وقد اسفرت نتائج البحث عن: - إن طلبة الجامعة يتمتعون بأصالة الذات. - عدم وجود فروق في

... Show More
View Publication Preview PDF