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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
Fri Aug 01 2025
Journal Name
Iop Conference Series: Earth And Environmental Science
Influence of Solar and Geomagnetic Activity on the Ionospheric Sporadic-E Layer Over Baghdad
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Abstract<p>This study examines the monthly mean diurnal variations of the ionospheric sporadic E (Es) layer’s critical frequency (<italic>foEs</italic>) and virtual height (<italic>h′Es</italic>) above Baghdad city (latitude 33.3˚N, longitude 44.4˚E) during Solar Cycle 22 (1988–1995). The analysis examines their correlation with solar activity, represented by sunspot numbers, and geomagnetic disturbances, particularly during the descending phase of the cycle. The findings revealed that <italic>foEs</italic> values were the highest during the solar maximum years (1989–1991), aligning with increased sunspot numbers and geomagnetic activity due to coronal mas</p> ... Show More
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Publication Date
Sun Jun 06 2010
Journal Name
Baghdad Science Journal
Using Neural Network with Speaker Applications
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In Automatic Speech Recognition (ASR) the non-linear data projection provided by a one hidden layer Multilayer Perceptron (MLP), trained to recognize phonemes, and has previous experiments to provide feature enhancement substantially increased ASR performance, especially in noise. Previous attempts to apply an analogous approach to speaker identification have not succeeded in improving performance, except by combining MLP processed features with other features. We present test results for the TIMIT database which show that the advantage of MLP preprocessing for open set speaker identification increases with the number of speakers used to train the MLP and that improved identification is obtained as this number increases beyond sixty.

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Publication Date
Sat Jun 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Internal control – Internal check
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Abstract

All the economic  units whether productive or service units , strive to achieve specific objectives , their presence and continuity depend on them and the quality of the performance and service present to the society . This units to be able to achieve their objectives , must own basic assets to perform the activities , and apply laws , systems , and instructions , in addition to legal , managerial , and financial authorities . So this units to endeavor maintain this assets , in addition to sound application of laws ,systems . and procedures to enhance their performance . For this purpose arise the role of internal control and internal check in maintenance of assets and sound application of&n

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Publication Date
Sun Apr 07 2013
Journal Name
Journal Of Educational And Psychological Researches
Psychophysiological Control in Behavior
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         The Feedback Concept has been spread as an organized trend for scientific research since it has a significant importance for human behavior and how it has been directed and controlled by the individual, feedback has numerous definitions but the simplest definition is; feedback is the information received by the individual from the output of his behavior, In addition to the mutual relationship between the individual and the stimulation that provide him with the basic information by the biological control of his behavior, Since feedback cannot be accomplished without receiving information from the inner and outer environment, the biological and physiological information become the ma

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Analysis of the structure of salaries of public sector workers for strategic planning purposes An analytical study in the general body of groundwater
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The research discusses the problem of salaries in the public sector in terms of the process of analyzing its structure and the possibility of benefiting from the information provided by the analysis process for the strategic planning process, and the General Authority for Groundwater has been adopted and one of the formations of the Ministry of Water Resources, which is centrally funded, to represent the salary structure of its employees (1117) employees be a field of research, as the salary structure in it was analyzed for the period between (2014-2019) using the quantitative approach to analysis and by relying on a number of statistical tools in the analysis process, including mathematical circles, upper limits, lower limits, p

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Publication Date
Thu Oct 03 2013
Journal Name
Heat Transfer-asian Research
CFD Simulation of Heat Transfer Augmentation in a Circular Tube Fitted with Alternative Axis Twisted Tape in Laminar Flow under a Constant Heat Flux
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Publication Date
Tue Jun 03 2014
Journal Name
Heat Transfer - Asian Research
CFD Simulation of Heat Transfer Augmentation in a Circular Tube fitted with Alternative Axis Twisted Tape in Laminar Flow under the Constant Heat Flux
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Publication Date
Tue Mar 01 2022
Journal Name
Iraqi Journal Of Physics
Effect of Carbon Nanoparticles on the Performance Efficiency of a Solar Water Heater
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Carbon nanoparticles are prepared by sonication using carbon black powder. The surface morphology of carbon black (CB) and carbon nanoparticles (CNPs) is investigated using scanning electron microscopy (SEM). The particles size ranges from 100 nm to 400 nm for CB and from 10 nm to 100 nm for CNPs. CNPs and CB are mixed with silicon glue of different ratios of 0.025, 0.2, 0.05, and 0.1 to synthesis films. The optical properties of the prepared films are investigated through reflectance and absorbance analyses. The ratio of 0.05 for CNPs and CB is the best for solar paint because of its higher solar water heater efficiency and is then added to the silicon glue . Temperature of cold water and temperature of hot water in storage tank were ta

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Publication Date
Mon Mar 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Modeling and Simulation of Sensorless Speed Control of a Buck Converter Controlled Dc Motor
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This paper investigate a sensorless speed control of a separately excited dc motor fed from a buck type dc-dc converter. The control system is designed in digital technique by using a two dimension look-up table. The performance of the drive system was evaluated by digital simulation using Simulink toolbox of Matlab.

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Publication Date
Sun Mar 01 2020
Journal Name
Iraqi Journal Of Physics
Increasing the conversion efficiency of KTP crystal using the pump-power technique
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In this study, the effect of pumping power on the conversion efficiency of nonlinear crystal (KTP) was investigated using laser pump-power technique. The results showed that the higher the pumping power values, the greater the conversion efficiency (η) and, as the crystal thickness increases within limitations, the energy conversion efficiency increases at delay time of (0.333 ns) and at room temperature. Efficiency of 80% at length of KTP crystal (L = 1.75 X 10-3 m) and Pin = 28MW, and also, compare the experimental results with numerical results by using MATLAB program. 

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