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Experimental Study Using the Passive Solar Chimney for Evaporative Cooling With PCM and CFM as a Thermal Energy Storage
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      In this work, a test room was built in Baghdad city, with (2*1.5*1.5) m3  in dimensions, while the solar chimneys (SC) were designed with aspect ratio (ar) bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB) that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled  in the bottom of TESB of vertical SC. The TESB was made from metallic iron sheets as a shell and fuelled by paraffin wax as phase change material (PCM). The PCM supported by copper foam matrix (CFM) to enhance thermal conductivity of wax. When heat is released from TESB to the air, a buoyancy force will be generated in chimney gaps. Then a difference in pressure between inside and outside test room leads to induce the air flow to test room through wet corrugated cellulose pad, where evaporative cooling (EC) occurs. Results of experimental work, that achieved in June, for 12 to24 hour in the test day, refer to effectiveness using EC to decrease the room temperature comparing. The system reduces test room temperature of up to 8.5~9.2 oC in 11:00 am to 3:00 pm and at highest effectiveness of EC, while minimum reduces in temperature of up to 3.5 oC in 8:00pm to 3:00 am. Also, the results showed the affectivity to using the TESB, during the night time for ventilation and EC, with lower effectiveness than from day time. The range of EC effectiveness equals 30.5-37.5 with a natural vent, while The maximum air change per hour (ACH) equals (3.8-6.187), and the maximum mass flow rate is equal to (36.651 kg.hr-1) at experimental evaluation of the system’s discharge coefficient value 0.371.

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Publication Date
Sun Jan 01 2017
Journal Name
مجلة كلية الادارة والاقتصادللدراسات الاقتصادية والادارية والمالية
تصميم الترتيب الداخلي األمثل باستعمال تقنية التخصيص النسبي المحوسب للتسهيالت )CRAFT)بحث تطبيقي في الشركة العامة لصناعة الزيوت النباتية – مصنع المأمون
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The facilities layout are among the most important of the most influential factors in the efficiency of the production system, and represents the systematic layout of the various work centers, tools, persons, and other auxiliary services within the factory. Careful selection of the technique that would be used in Re-layout, represents an important step in reaching to the optimum layout that keeps on reducing handling costs and reduce unnecessary movement of materials, as well as the regularity and functioning of the flow of materials through the facilities. The research aims to propose a new layout of (Al-M'ammon Factory / The General Company for Vegetable Oils Industry), and then re-layout according to the new propose layout by using of te

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Umbilical cord drainage versus intraumbilical cord oxytocin injection in management of third stage of labour
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Background: Postpartum hemorrhage is an important cause of maternal morbidity and mortality. Considerable difference of opinion exist regarding the optimal approach to the management of the 3rd stage of labour, practice varies between countries &between units.
Objectives: To evaluate the effectiveness of intra umbilical vein injection of oxytocin and umbilical cord driange in shortening the duration of third stage of labour.
Patient and Methods: In this randomized controlled study, 100 women were enrolled in this study they divided into three groups. (Group 1 ,N =30 )received 20 units of oxytocin diluted in 20 ml 0.9% saline solution injected in the umbilical vein after clamping.(Group 2, N = 34) placental cord drainage.(Group

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Publication Date
Sun May 06 2007
Journal Name
كلية التربية البدنية وعلوم الرياضة/جامعة بغداد .
تأثير التمرينات الاوكسجينية واللاأوكسجينية في الوحدة التدريبية لتطوير بعض القدرات الوظيفية والبدنية للاعبي كر ة القدم بعمر (13-14)سنة. رسالة ماجستير
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Publication Date
Thu Jan 02 2020
Journal Name
Journal Of The College Of Languages (jcl)
Linguistic Errors in second language learning through Error Analysis theory: هه‌ڵه‌ زمانییه‌كان له‌ فێربوونی زمانی دووه‌مدا (له‌ ڕوانگه‌ی تیۆری شیكاری هه‌ڵه‌ییه‌وه‌)
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Second language learner may commit many mistakes in the process of second language learning. Throughout the Error Analysis Theory, the present study discusses the problems faced by second language learners whose Kurdish is their native language. At the very stages of language learning, second language learners will recognize the errors committed, yet they would not identify the type, the stage and error type shift in the process of language learning. Depending on their educational background of English as basic module, English department students at the university stage would make phonological, morphological, syntactic, semantic and lexical as well as speech errors. The main cause behind such errors goes back to the cultural differences

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
معوقات تطبيق الإدارة الإلكترونية في وزارة التربية والتعليم بسلطنة عمان(البوابة التعليمية الإلكترونية أنموذجاً) من وجهة نظر موظفي المديرية العامة لتقنية المعلومات
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Drawbacks of Implementing Electronic Management in the Ministry of Education (A sample: Oman Educational Portal) from the Point of View of IT Staff. The study aimed at discovering the drawbacks of implementing electronic management in the Ministry of Education (a sample: Oman Educational Portal) from the point of view of IT staff, and that is by answering the following questions: - What are the main drawbacks (administrative, financial, technical and drawbacks related to human resources) that hinder implementing the electronic management in the Ministry of Education (a sample: Oman Educational Portal) from the point of view of IT staff? - Are there any statistical significance differences at the level (0.05) between study samples on the

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Publication Date
Sun Mar 26 2023
Journal Name
Arab Science Heritage Journal
الاديب الكاتب والمؤرخ الفقيه يحيى بن خلدون (ت 780هـ/ 1379م) كاتب ديوان الانشاء في دولة بني زيان (633-962هـ/ 1235-1554م) بتلمسان
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    A prominent figure such as Yahya bin Khaldoun and a scholar of the moroccan countries in the medieval era, and had a special place in the history of the country and the state of Bani Zayan, and the positions he occupied in it and left his scientific, literary and historical traces, leaving him an imprint in the course of history and its events, and in this study
I dealt with the research: his personal life : his name and lineage, then his upbringing and his family.

    The aim of the study is to know this character in the details of his personal and scientific life, according to the historical descriptive research method, including description and presentation of events, and linking them in a

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Publication Date
Thu Dec 29 2022
Journal Name
Journal Of The College Of Languages (jcl)
Construction Grammar in Kurdish Language: ڕێزمانی بونیادنان لە زمانی کوردیدا توێژینەوەیەکی هەڵهێنجراو(مستل)ە لەنامەی دکتۆراوە وەرگیراوە
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This research is under the title (Construction Grammar in the Kurdish language), which in turn is an attempt to present grammar and Kurdish grammar from the perspective of the constructive of Cognitive Linguistics. The construction as a term in the Kurdish language base was not recent, as it was discussed in other schools in a specific way from the perspective of language schools, but the subject of construction with a perceived background includes specific purposes, which is how to build the linguistic base by being a template accessible to its speakers, and in the cases of speaking it, not to mention how it is perceived and the level it is familiar with by its speakers. The nominal purpose of the Construction is Unification of form-mea

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Publication Date
Thu Feb 15 2024
Journal Name
Al-manhaj Library
Multivariate Analysis (Second Edition)
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This Book is intended to be textbook studied for undergraduate course in multivariate analysis. This book is designed to be used in semester system. In order to achieve the goals of the book, it is divided into the following chapters (as done in the first edition 2019). Chapter One introduces matrix algebra. Chapter Two devotes to Linear Equation System Solution with quadratic forms, Characteristic roots & vectors. Chapter Three discusses Partitioned Matrices and how to get Inverse, Jacobi and Hessian matrices. Chapter Four deals with Multivariate Normal Distribution (MVN). Chapter Five concern with Joint, Marginal and Conditional Normal Distribution, independency and correlations. While the revised new chapters have been added (as the curr

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Publication Date
Thu Feb 15 2024
Journal Name
Al-manhaj Library
Multivariate Analysis - Second Edition
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This Book is intended to be textbook studied for undergraduate course in multivariate analysis. This book is designed to be used in semester system. In order to achieve the goals of the book, it is divided into the following chapters (as done in the first edition 2019). Chapter One introduces matrix algebra. Chapter Two devotes to Linear Equation System Solution with quadratic forms, Characteristic roots & vectors. Chapter Three discusses Partitioned Matrices and how to get Inverse, Jacobi and Hessian matrices. Chapter Four deals with Multivariate Normal Distribution (MVN). Chapter Five concern with Joint, Marginal and Conditional Normal Distribution, independency and correlations. While the revised new chapters have been added (as the curr

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Publication Date
Thu Jun 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Performance Improvement of Neural Network Based RLS Channel Estimators in MIMO-OFDM Systems
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The objective of this study was tointroduce a recursive least squares (RLS) parameter estimatorenhanced by using a neural network (NN) to facilitate the computing of a bit error rate (BER) (error reduction) during channels estimation of a multiple input-multiple output orthogonal frequency division multiplexing (MIMO-OFDM) system over a Rayleigh multipath fading channel.Recursive least square is an efficient approach to neural network training:first, the neural network estimator learns to adapt to the channel variations then it estimates the channel frequency response. Simulation results show that the proposed method has better performance compared to the conventional methods least square (LS) and the original RLS and it is more robust a

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