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%.
واقع الدراسات الاورومتوستطية في الجامعات العراقية "دراسة حالة كلية العلوم السياسية - جامعة بغداد"
Proposals to raise awareness of the rights of minorities and secure their freedoms have begun to receive attention Internationally. It is escalated, especially after the increasing impact of wars and conflicts on these situations Minorities, and UNESCO stresses the need to take over information and communication policies Greater attention to protect minority rights.
Hence the importance of our research, the problem of which lies in the main question: (What is the role Radio Republic of Iraq has played in promoting awareness of minority rights at the level : Public and Social?) . As one of the Iraqi media networks , laws oblige them to pay attention to the rights of minorities and to spread a culture of pluralism , diversity
... Show MoreThe study aimed to identify the awareness level of hidden curriculum among field education students, College of Education, Hail University. To identify the different awareness level of hidden curriculum among field education students depending on specialization variable, and grade variable in curriculum and instruction course, a descriptive survey method was used. The study sample consisted of (182) students: 78 students in Islamic Culture major, 46 primary major and 58 in physical education. To achieve the study objectives, a hidden curriculum awareness scale was designed included (36) items. The study results showed: the awareness level of hidden curriculum among students of field education, Education College, Hail University, achieved
... Show MoreThe research aims to find out the effect of PEDODE Strategy on the acquisition of historical concepts of First Intermediate Grade. To achieve this goal, the researcher has put forward this zero hypothesis: There is no statistically significant difference at the level of (05,0) between the mean of the students' marks in the experimental group who study the history subject using PEDODE strategy and that of the students' marks in the control group who study the subject according to the traditional method in the post-testing on the acquisition of historical concepts. The sample of the study consists of (62 female-students) of First Intermediate Grade in the Directorate of Baghdad Education/ Karkh2nd for the academic year 2016-2017. The sampl
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The nanocompsite of alumina (Al2O3) produced a number of beneficial effects in alloys. There is increasing in resistance of materials to surface related failures , such as the mechanical properties , fatigue and stress corrosion cracking .The experimental results observed that the adding of reinforced nanomaterials type Al2O3 enhanced the HB hardness, UTS, 0.2 YS and ductility of 2014 Al/Al2O3 nano composites . the analysis of experiments, indicated that The maximum enhancement was observed at 0.4 wt.% Al2O3. The ultimate improvement percentage were 15.78% HB hardness, 18.1% (UTS), 12.86% (
... Show MoreIt could be said that the essence of the “quota” is the state’s intervene as external power in bringing positive change for the benefit of the disadvantaged women and cultural minorities, and from the perspective that compensatory justice requires dealing differently with the different parties culturally and economically for the benefit of those deprived of them. Practicing of quotas merely, does not mean the full achievement of equality between cultural and sexual components in general, but it’s a big leap towards achieving this crucial goal, since the latter necessarily requires a range of legal and non-legal mechanisms aimed at empowering women and expanding their capabilities as a whole. On the other hand, in the absence of a
... Show MoreObjectives of the study: The main objective of the study is to assess the prevalence of hypertension among
cardiac diseases patients and to fiend out relation ship between hypertension and cardiovascular diseases.
Methodology: A descriptive study, using interviewer and questionnaire technique was conducted on cardiac
diseases inpatients of clinic unite at Kirkuk and Azady hospitals from 17th ,June ,2012 to 1st, March , 2013.
Non – probability (purposive) sample of (148) adult patients, (81) females and (67) males with heart disease are
selected from inpatients of clinic unite at Kirkuk and Azady hospitals at kirkuk city. Questionnaire was
developed to assess the items which are related to heart disease patient's (Dise
ان دراسة الاحوال الاجتماعية في الاسكندرية خلال العصر المملوكي امر مهم لاسيما ان الحياة الاجتماعية في مصر عامة والاسكندرية خاصة اتصفت بكونها بطيئة التغيير خلاف جوانب الحياة الاخرى التي اتصفت بسرعة تغير مجراها كما وان تاريخ الاسكندرية الاجتماعي كان زاخرا بالكثير من نواحي النشاط الانساني من ميادين العمل والتسلية والترفيه والاعياد والافراح فضلا عن تنوع عناصره السكانية وهذا ما سنتناوله ضمن محاور هذا البحث.
... Show MoreThe current researsh is aimed to pay attention on concept of human resources hard (Difficult) to manage. Such style of human resourcses has emerged to form anew challenge for busniess organizations.
Management such human resources entails first determing incentives of their behaviour models. Analyzing these models will be important to strategical management of them from work.
In nutshell, this researsh try to recommendation of contemporary literature about future of difficult (hard) human resources management.