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Design and Implementation of an Automatic Control for Two Axis Tracking System for Applications of Concentrated Solar Thermal Power
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The present work presents design and implementation of an automated two-axis solar tracking system using local materials with minimum cost, light weight and reliable structure. The tracking system consists of two parts, mechanical units (fixed and moving parts) and control units (four LDR sensors and Arduino UNO microcontroller to control two DC servomotors). The tracking system was fitted and assembled together with a parabolic trough solar concentrator (PTSC) system to move it according to information come from the sensors so as to keep the PTSC always perpendicular to sun rays. The experimental tests have been done on the PTSC system to investigate its thermal performance in two cases, with tracking system (case 1) and without tracking system (case 2). The experimental results showed that the average solar radiation falling on the PTSC prototype in the two cases during the same time was 854 and 701 watt/m2, respectively, which means an increase in the solar radiation about 21.8 % when using tracking system. It was found that the average useful heat gain output of solar collector was equal to (376.2, 252.6 watt) for the two cases, respectively, so there was an increase of about 48.9 % when using the tracking system. Also, the average thermal efficiency of the PTSC was found to be (20.7, 26.5 %) for the two cases, respectively, which means an increase in the average efficiency by 28% with use of tracking system compared to the fixed case.

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Publication Date
Mon Nov 19 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Effective of incentive system on development of Research creativity for professors of university: Analytical study at private collage in Baghdad
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This research aims at studying and analyzing the creative research thinking of the educational staffs in private universities and colleges, and also the role of incentives, in its materialistic and moral sides in the development of such thinking and the pack of restraints which cause decline in interest level of the scientificresearch, and its weak role in the development of universities in Iraq, despite the interest of the Ministry of Higher Education and Scientific Research in Iraq in scientific research as part ofits academic and humanitarian targets.Based on study and analysis, and the using if some of statistical methods such as the Alpha Chronobaghcoefficient and the (T. Test)(F. Test),the research reached a number of conclusions.

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Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Numerical Investigation of Transient Heat Conduction through a Thermal Insulation of Temperature Dependant Thermal Properties
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The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the i

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Publication Date
Thu Nov 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The Marginal Fitness of CAD/CAM All Ceramic Crowns Constructed by Two Typesof Direct Digitization Techniques (An In Vitro Study)
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Background: In capturing a negative image, the digital impression secures a digital record for the purposeof designing and creating restorations. The introduction of scanning system presents a paradigm shift in the way of the dental impression procedure and encourages the accuracy of obtained restoration especially in the marginal area as a result of producing accurate final impression The digital system offers many advantages over the Conventional method.. The objective of this present in vitro study was to evaluate the marginal fitness of all ceramic crowns fabricated by direct digital scanning of the prepared tooth using two types of intra-oral cameras (Bluecam camera with strip light projection technique and Omnicam camera with video sa

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Publication Date
Mon Sep 09 2024
Journal Name
مداد الاداب
Lexical Stylistic Analysis of Two ‎Extracts from Tale of Two Cities: ‎A Contrastive Study
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Since the time it emerged, stylistics, as a field of knowledge which ‎combines both linguistics and literature, acquired a special status in the ‎linguistic arena. Its significance in complementing the meaning ‎delivered by linguistic means has been proven and acknowledged ‎through numerous stylistic analytic attempts of different literary works ‎and in different languages. The question put forward in this paper is ‎whether or not the stylistic analysis can work as effectively on translated ‎texts as it does on the original ones without having the results reached ‎by the analysis distorting the meaning of the original text. An attempt to ‎investigate this question is made herein by conducting a lexical stylistic ‎analysi

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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Robust Color Image Encryption Scheme Based on RSA via DCT by Using an Advanced Logic Design Approach
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Information security in data storage and transmission is increasingly important. On the other hand, images are used in many procedures. Therefore, preventing unauthorized access to image data is crucial by encrypting images to protect sensitive data or privacy. The methods and algorithms for masking or encoding images vary from simple spatial-domain methods to frequency-domain methods, which are the most complex and reliable. In this paper, a new cryptographic system based on the random key generator hybridization methodology by taking advantage of the properties of Discrete Cosine Transform (DCT) to generate an indefinite set of random keys and taking advantage of the low-frequency region coefficients after the DCT stage to pass them to

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Publication Date
Thu Sep 15 2022
Journal Name
F1000research
Comparison between the effects of two treatment regimens from GINA guidelines step 3 on quality of life and inflammatory biomarkers of pediatric asthmatic patients: an observational study
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Background: Asthma is a complicated condition characterized by chronic airway inflammation and airflow restriction, resulting in various respiratory symptoms such as shortness of breath, wheezing, coughing, and chest tightness. The research intended to evaluate and compare the clinical outcomes of two interchangeable treatment regimens administered to a group of Iraqi asthmatic children.

Methods: This observational clinical study was conducted on a sample of pediatric Iraqi asthmatic patients in the central pediatric hospital in Baghdad. The study enrolled asthmatic children with moderate persistent asthma, who a specialized physician had diagnosed. Patients had been allocated

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Publication Date
Sun Sep 15 2019
Journal Name
Biochemical And Cellular Archives
VARIOUS APPLICATIONS OF CARBAZONE DERIVATIVES AND THEIR METAL COMPLEXES : A REVIEW
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Carbazone Derivatives (CD) (semicarbazone, semithiocarbasone) are produced by the condensation reaction between a aldehyde (or ketone) with a carbazide derivatives (semicarbazide, semithiocarbazide). CD and their metal complexes existent a wide range of implementation that stretch from their ply in the medicinal and pharmaceutical area because of their major significant pharmacological characteristic such as anti-fungal,anti-bacterial, anti-cancer, anti-human immunodeficiency virus, anti-inflammation, anti-neoplastic,inhibition corrosion, antioxidation, antiradical. This paper reviews the definition, importance and various applications of carbazone derivatives with transitional meta

Publication Date
Wed Jan 01 2025
Journal Name
Lecture Notes In Networks And Systems
Comparison Between the Performance of Human Translators and AI-Supported Applications
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This study aims to conduct an exhaustive comparison between the performance of human translators and artificial intelligence-powered machine translation systems, specifically examining the top three systems: Spider-AI, Metacate, and DeepL. A variety of texts from distinct categories were evaluated to gain a profound understanding of the qualitative differences, as well as the strengths and weaknesses, between human and machine translations. The results demonstrated that human translation significantly outperforms machine translation, with larger gaps in literary texts and texts characterized by high linguistic complexity. However, the performance of machine translation systems, particularly DeepL, has improved and in some contexts

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Publication Date
Thu Aug 08 2024
Journal Name
Journal Of Inorganic And Organometallic Polymers And Materials
Schiff-Base System of Glutaraldehyde Crosslinked Chitosan-Algae-Montmorillonite Clay K10 Biocomposite: Adsorption Mechanism and Optimized Removal for Methyl Violet 2B Dye
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Publication Date
Thu Jun 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesis of Novel Porphyrin Derivatives and Investigate their Application in Sensitized Solar Cells
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Solar energy has significant advantages compared to conventional sources such as coal and natural gas, including no emissions, no need for fuel, and the potential for installation in a wide range of locations with access to sunlight. In this investigation, heterocyclic derivatives were synthesized from several porphyrin derivatives (4,4',4",4"'-(porphyrin-5,10,15,20-tetrayl) tetra benzoic acid) compound (3), obtained by reaction Pyrrole with 4-formyl benzoic acid. Subsequently, porphyrin derivative-component amides 5a, 5b, and 5c were produced by reacting compound (3) with amine derivatives at a 1:4 molar ratio. These derivatives exhibited varying sensitivities for utilization in solar cells, with compound 5a displaying the highest power

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