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joe-796
Thermal Efficiency for Passive Solar Chimney with and Without Heat Storage material
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In this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air induced through the test room by SC effect. The governing equation of Computational Fluid Dynamic (CFD) model was developed by the effective heat capacity method equation to describe the heat storage and release from PCM-CFM. Practical and computational Results referred to increase in thermal conductivity of the paraffin wax that supported by CFM than 10 times, while the ventilation effect is still active for hours after sun set amount. The maximum ventilation mass flow rate with TESB collector was 36.651 kg/hr., when the overall discharge coefficient equals 0.371. Also, the experimental results referred to the best working angle range 45~60o, while the highest approaching temperature (between air and collector) was appeared for the double passes flat plate collector. Results gave higher heat storage efficiency 47% when the maximum solar radiation 780 W/m2 at 12.00 pm, and the energy summation through duration of charging time was 18460 kJ. Double passes SC at 60o angle presented the highest efficiency with value approaching to 73%, while TESB collector efficiency depicted highest efficiency value 70% at 12:00 pm.

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Some Estimation Methods Of GM(1,1) Model With Missing Data and Practical Application
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This paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt  properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1)  is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method  (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to

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Publication Date
Wed Jul 01 2020
Journal Name
Iop Conf. Series: Materials Science And Engineering
Structural Performance of Slender RC Columns with Cross and Square-Shaped under Compression Load
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Abstract<p>The idea of using slender Reinforced Concrete (RC) columns with cross-shaped (+-shaped) instead of columns with square-shaped was discussed in this paper. The use of +-shaped columns provides many architectural and structural advantages, such as avoiding prominent columns edges and improved the structural response of member. Therefore, this study explores the structural response of slender +-shaped columns experimentally and numerically by nonlinear finite element analysis using Abaqus simulation tools. The results showed an excellent convergence in strength between numerical and test results with an average standard deviation of 0.05 and 0.07. Besides that, the use of +-shaped column</p> ... Show More
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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
Logical thinking and its relation with problem Solving among female instructors in the university
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problems with its unobvious effect on scientific creativity and information. Problem solving is one of main goals of researchers because it develops their right logical thinking methods. The present study aims at measuring logical thinking among female it structures in the university mea swing problem solving among them ,identifying statically differences significance in logical thinking among female instructors in the university according to (Specialization Variable), identifying differences significance in problem Solving among female instructions in the university according to ( Specialization Variable) and identifying the Correlation between logical thinking and problem solving among female instructors in the university. The sample c

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Publication Date
Sun Jun 01 2025
Journal Name
Journal Of Physics: Conference Series
Fabrication of (unsaturated polyester / carrot fibers) gel coat with high impact and compressive strengths
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Abstract<p>Due to the low cost of both unsaturated polyester resin and the plant fibers along with protect of the environment, the wasted Carrot fibers were employed in this study to strengthen and color the resin. Carrot peels powders have been incorporated with unsaturated polyester/ natural fibers (UPE/C.F) gel coats to form a good candidate with good mechanical behaviors in different industrial applications. The wasted carrot peels fibers, were dried, crashed and milled into micro particles sizes (2.5% microns) to improve the mechanical properties (impact energy, Compressive load and Elastic Modulus) of unsaturated polyester. Micro carrot fibers (C.F) have been loaded to unsaturated fibers a</p> ... Show More
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Publication Date
Fri Dec 31 2021
Journal Name
Teikyo Medical Journal
Evaluation of Serum Angiogenic and Anti-angiogenic Markers in Pregnant Women with Placenta Accreta
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Over the last 40 years, rate of cesarean delivery has risen from less than10% to over 30% around the world, and almost simultaneously a 10-foldraise in the incidence of placenta accrete spectrum. Fine coordinationamong vascular endothelial growth factor, soluble fms-like tyrosine kinase1 and placental growth factor is important for normal placentaldevelopment and trophoblast invasion. To measure and compare the levelsof circulating vascular endothelial growth factor, placental growth factorand soluble fms-like tyrosine kinase 1 in pregnant women with placentaaccreta to a control group. A case control study which involved one hundredpregnant females were recruited from the Obstetric ward in BaghdadTeaching Hospital who were pregnant with 28

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Publication Date
Fri Nov 01 2019
Journal Name
Advances In Intelligent Systems And Computing
Analysis of the Relationship Between Traffic Accidents with Human and Physical Factors in Iraq
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Publication Date
Thu Aug 22 2013
Journal Name
International Journal Of Dermatology
Skin tumors and skin infections in kidney transplant recipients vs. patients with pemphigus vulgaris
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Abstract<sec><title>Background

Pemphigus vulgaris is an autoimmune disease of the skin and mucous membrane. Renal transplantation is a common procedure in Iraq, and these patients required prolonged use of immunosuppressive drugs.

Objective

To study the frequency of skin tumors and infections in patients with pemphigus vulgaris compared with renal transplant recipients and normal controls.

Patients and methods

One hundred kidney transplant recipients, their ages ranged from 14 to 70 (46.65 ± 4.74) years

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Publication Date
Thu May 22 2025
Journal Name
Cureus
The Treatment of Acute Cutaneous Leishmaniasis With Oral Zinc Bisglycinate and Oral Hydroxychloroquine Sulfate
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Publication Date
Thu Apr 27 2023
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Prevalence and Demographic Characteristics of Metabolic Syndrome in Iraqi Patients with Acute Coronary Syndrome
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خلفية البحث: المتلازمة الأيضية عند المرضى العراقيين المصابين بالمتلازمة التاجية الحادة قليلا ما تمت دراستها. الأهداف: دراسة الخصائص المجتمعية-السكانية للمرضى العراقيين المصابين  بالمتلازمة الايضية مع المتلازمة التاجية الحادة. المرضى وطرق العمل:  شملت الدراسة المقطعية 150 مصابا بالمتلازمة التاجية الحادة الذين يعالجون في وحده العناية القلبية في مستشفى اليرموك التعليمي في بغداد للفترة من منتصف كانون الث

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Publication Date
Fri Dec 15 2023
Journal Name
Iraqi Journal Of Laser
Evaluation of Lithium Disilicate Surface Morphology Treated with Er,Cr:YSGG and Fractional CO2 Laser
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Abstract: The use of indirect, all-ceramic restorations has grown in popularity among dentists. Studies have demonstrated that for indirect ceramic restorations to be effective over time, cement and ceramic must be bonded in a stable manner. Chemical, mechanical, and laser irradiation are among the methods used to precondition ceramic surfaces in order to increase bond strength.The objective of the study: This study was performed to investigate the roughness values and surface topography of lithium disilicate glass-ceramic treated with conventional methods and different Er,Cr:YSGG, and fractional CO2 laser conditioning parameters.Material and methods:<

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