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%.
It is summarized that Abu-Baker Al-Soly is one of Arabic Muslim scientists who had special style in literary writing specifically in sciences and knowledge that had depended on the encyclopedia culture gained from various fields of science , this means that he was an individual who had participated to characterize features of Islamic –Arabic history enhanced the rules of it , this matter would encourage us to know the method and style of writing in the field of intellectual life in which the writer depended on the procedures direction of scientists that he lived in the Abbasid era .
يتناول هذا البحث موقف ( صحيفة الاهرام) المصرية من تطورات الصراع في جمهورية الكونغو الديمقراطية خلال الفترة (1964 -1965) وهي مرحلة اتسمت باحتدام الازمات السياسية والنزاعات الداخلية في الكونغو مع زيادة التدخل الاجنبي في شؤون البلاد المتمثل بالولايات المتحدة الامريكية وبلجيكا وعلى هذا الاساس تم اختيار موضوع البحث والذي حددت بدايته بالتزامن مع عودة مويس تشومبي الى السلطة ، وما رافقها من صراعات وتمردات في الاقاليم
... Show MoreBrainstorming is one of the fundamental and necessary concepts for practicing the auditing profession, as auditing standards encouraged the implementation of brainstorming sessions to reach reasonable assurance about the validity of the evidence and information obtained by the auditor to detect fraud, as the implementation of brainstorming sessions and the practice of professional suspicion during the audit process lead to increase the quality of auditing and thus raise the financial community's confidence in the auditing profession again after it was exposed to several crises that led to the financial community losing confidence in the auditing profession.
The research aims to explain the effect of brain
... Show MoreIt is axiomatical that the narrative prospective is profoundly significant to the writer who intends to commence his sketch of projected novel. It is the pillar of comprehensive absorbing as the writer should commit himself to circular his own concepts to the reader of his narrative characters.
The dilemma of plot-perception is a twofold aspect; partly offers the question: what is the authors stand in regard to his characters? And: what is the aim of this theme? These correlative questions are inseparable since the reader who wishes
... Show Moreيُعد الوزن الاقتصادي للهند من أبرز عناصر قوتها الجيوسياسية، إذ تُصنف الهند ضمن أكبر الاقتصادات عالميًا، مدعومة بحجم سكاني ضخم وسوق استهلاكي واسع ونمو متسارع في قطاعات الصناعة والخدمات والتكنولوجيا. حقق الاقتصاد الهندي نموًا قويًا خلال السنوات الأخيرة، مع استمرار معدل نمو الناتج المحلي ضمن نطاق مرتفع مقارنة بكبرى الاقتصادات العالمية، حيث تتوقع عدة مؤسسات دولية نموًا يقارب 6.3–7% خلال 2026–2027.
Abstract:
Objective: The study was done to evaluate nurses’ knowledge and practices toward physical restraint at critical care unit
Methodology: Fifty nurses, who were selected by a non-probability (convenient) sampling method, participated in this descriptive study. The instrument of the study was knowledge parts of the questionnaire were initially developed in the U.S.A for nursing homes; in 2006 they were adopted for all hospital units by the original developers. The knowledge section of the questionnaire consisted of 20 items, which were used to measure knowledge of nurses towards the definition, indications and contra
... Show Moreمقدمة introduction تُعد تقنيات الذكاء الاصطناعي قاطرة الثورة الصناعية الرابعة، إذ تجاوزت حدود البرمجة التقليدية إلى التعلم العميق الذي مكّن الآلات من تنفيذ مهام بشرية معقدة، مثل تحليل الصور، ومعالجة اللغات الطبيعية، وإنتاج محتوى إبداعي. فأصبحت التطبيقات تعتمد على الذكاء الاصطناعي في جميع القطاعات، من الرعاية الصحية إلى التعليم، ومن الأمن إلى الفنون. ومع ذلك، مثلما أن كل تقدم يحمل في طياته إمكانات هائلة، فإنه يج
... Show MoreEducational and psychological adjustment considered to be one of the effective and serious matters at people dealings and behaviors. Generally, psychological adjustment reflects positively on an individual mental health and their capability to be creative at their field. In contrast to those people who lack this feature. As for educational adjustment, it refers to the compatibility and harmony between an individuals and people around. Thus, these features should be available among students particularly those who stay in students' hostel since they live far from their families. The findings of study revealed that there is Educational and psychological adjustment between male and female. Besides, significant differences were showed
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The current research aims to determine the relationship of the impact of the components of the financing structure, especially financing through debts, as well as the earnings per share in the value of the shares of companies listed in the Iraq Stock Exchange. The research sample and identifying the strength of the combined effect of the ratio of financing through debt and earnings per share in maximizing The market value of the firm and the real value, as well as the variation between these relationships according to model of the real value of the companies and the market value of the research sample companies. The research community is represented by the Iraq Stock Exchange, while a conditional deliberate sample
... Show MoreCompanies compete greatly with each other today, so they need to focus on innovation to develop their products and make them competitive. Lean product development is the ideal way to develop product, foster innovation, maximize value, and reduce time. Set-Based Concurrent Engineering (SBCE) is an approved lean product improvement mechanism that builds on the creation of a number of alternative designs at the subsystem level. These designs are simultaneously improved and tested, and the weaker choices are removed gradually until the optimum solution is reached finally. SBCE implementations have been extensively performed in the automotive industry and there are a few case studies in the aerospace industry. This research describe the use o
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