The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.
Education received the attention of the monarchy in Iraq, especially after the developments that the country witnessed after Iraq gained independence and joined the League of Nations in 1932 AD in all political, economic and cultural aspects. In this regard, due to its distinguished geographical location, where the atmosphere, the natural environment and the religious and political standing were available, which made it a center of attraction for most Iraqi families and political figures. Learning and pioneering the path of knowledge, so it witnessed a great prosperity in secondary education, so several important schools appeared that contributed to advancing the wheel of learning forward, including Baghdad College High Schoo
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This research aims to identify the role of Psychological Capital (PsyCap) in the Spirituality at the Workplace (SAW) for a sample of the teaching staff of the four Colleges of the University of Kufa reached (200) out of (470) teaching, and to achieve the objective of this research and through access to research and studies of foreign adopted researchers standards scales of research variables, since it relied on the model (Luthans, Youssef, et al., 2007) to represent the components of Psychological Capital (self-efficacy, and hope, and optimism, and resilience), and given the attention organizations in the human element because of it
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It has became necessary helping the children to developing same of educational values which can be drawn from daily situations which the live. Especially the childhood stage is the basic building of value individual content since its establishment the societies take care of learning children and take care of them. Through their institutes which depended on, in this function. Therefore the importance of this, research is coming from the importance of this age stage and from importance and necessity of children aguirement the educational values and its development to them, and the importance this research coming from depending on guidance program with new content and it is (al bum of pictures) fro
... Show Moreان نجاح رياض الاطفال في تحقيق اهدافها يتوقف الى حد كبير على معلمة الروضة التي تزود الطفل بالخبرات ، فهي تمثل الام البديلة للطفل ، وتقع على عاتقها مسؤوليات نفسية واجتماعية واخلاقية نحو اطفال الروضة ، لدلك فان معلمة الروضة تقوم بعدة ادوار في رياض الاطفال ، فهي ممثلة لقيم المجتمع وتراثه التي تسعى الى غرسها في الطفل .
وعليه فان ليس كل من تتقدم للعمل في رياض الاطفال تصلح ان تكون معلمة ناجح
... Show MoreIn this paper, we introduce and study a new concept (up to our knowledge) named CL-duo modules, which is bigger than that of duo modules, and smaller than weak duo module which is given by Ozcan and Harmanci. Several properties are investigated. Also we consider some characterizations of CL-duo modules. Moreover, many relationships are given for this class of modules with other related classes of modules such as weak duo modules, P-duo modules.
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المستخلص
يعد تقييم اداء العاملين احد اهم الركائز الاساسية التي يتوقف عليها نجاح أي منظمة تسعى بأن تتطور وتتميز بأنشطتها واداءها وبالأخص المنظمات التي لها خصوصية في عملها كالأجهزة الرقابية التي تعتمد في اداء انشطتها ومسؤولياتها على كفاءة مواردها البشرية, ومن هذا المنطلق يهدف هذا البحث الى تصميم انموذج ثلاثي المحاور (المؤهلات والقدرات، الاداء والانجاز، التعاون والالتزام الوظيفي) ثُماني المستويات
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يهدف البحث لمحاولة دراسة واقع ادارة الوقت لدى عينه من رؤوساء الأقسام العلمية في كليات ومعاهد هيئة التعليم التقني اذ بلغ حجم العينة (47% ) فرداً تم احتيارهم عشوائياً من (15) كلية ومعهد موزعة في (69 من محافظات القطر وبلغ حجم عينة البحث (17%) من عدد رؤوساء الاقسام العلمية في الهيئة ، ولغرض جمع البيانات تم أعداد استمارة استبيان تمت صياغتها بشكل يؤمن توثيق الوقت الفعل
... Show MoreThe Dictionary of Countries by Yaqut al-Hamawi is one of the most important sources that researchers rely on in everything related to geography in knowing the names of places and countries, and the important historical information it contains about different cities and countries
هدف ال الأسلوب المعرفيّ م الإد ا ركيّ اضة للبنات، والتعرّف على علاقة التنظ ة وعلوم الر ة البدنّ ة التر لّ ة في ات المرحلة الثانّ طال إنّه احثتان اضة للبنات، وأفترضت ال ة وعلوم الر ة البدنّ ة التر ل ة في ات المرحلة الثان عض طال التأمّليّ الاندفاعيّ لدى اس الأسلوب المعرفيّ التأمّليّ الاندفاعيّ لدى عیّنة م الإد ا ركيّ ونتائج مق اس التنظ ة بین نتائج مق
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