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Numerical Study for HAWT Wake shape with different Angles of Attack
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Increasing world demand for renewable energy resources as wind energy was one of the goals behind research optimization of energy production from wind farms. Wake is one of the important phenomena in this field. This paper focuses on understanding the effect of angle of attack (α) on wake characteristics behind single horizontal axis wind turbines (HAWT). This was done by design three rotors different from each other in value of α used in the rotor design process. Values of α were (4.8˚,9.5˚,19˚). The numerical simulations were conducted using Ansys Workbench 19- Fluent code; the used turbulence model was (k-ω SST). The results showed that best value for extracted wind energy was at α=19˚, spread distance of wake behind single HAWT was inversely proportional with α value. Highest turbulence intensity level was in small values of α =4.8֯ and 9.5֯, which explain presence of meandering phenomenon in these two cases on contrast of α=19֯, while symmetry in wake shape was more obvious in α=19֯ than other cases due to the moderate turbulence intensity which was found in this case, which indicates that lowest aerodynamics loads on rotor components was in α=19˚. So best distribution for turbines in farm could be achieved at use high values of α in comparison to low values.

 

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Publication Date
Tue Jan 30 2018
Journal Name
Iraqi Journal Of Science
Evaluation of Orbital Maneuvers for Transition from Low Earth Orbit to Geostationary Earth Orbit
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The transition from low Earth orbit 200-1500 (km) to geostationary Earth orbit 42162 (km) was studied in this work by many methods of transfer. The delta-v requirement (Δv), the time of flight (Δt), the mass ratio of propellant consume (Δm/m) and total mass was calculated for many values altitude in the same plane also when the plane is change. The results from work show that (Δv) that required for transfer when the plane of orbit change is large than (Δv) required when the transfer in coplanar maneuvers while the bi-elliptical transfer method need time of transfer longer than a Hohmann transfer method. The most energy efficiency was determined when the transfer in coaxial between elliptical orbits

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
Analysis of Precipitation and Precipitable Water Vapor over Iraq for the Period 1948-2011
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The water vapor is one of the constituent elements of the rain and the superiority
of its importance in the study of climate because it is the basis on which depends all
the different aspects of condensation. The purpose of research is to analyze the time
series of the Baghdad station andan analyze these series to see whether there is a
relationship between these two variables. Obtained the data used in this research
from the National Center for Environmental Prediction for the period from 1948 to
2011. The use of statistical criteria included linear regression and Mann Kandal test
to find the link. The results of time series monthly presence decrease in rainfall and
all months except October, either the results o

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Publication Date
Sun Oct 22 2023
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization and Evaluation of Antimicrobial Activity for New Heterocyclic Derivatives Containing Pentagonal, HexagonalRings.
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This research, involved a series of some new compounds containing different hetero cyclic new pentagonal and hexagonal rings, through the reaction of 2-mercapto-3-phenyl-4(3H)quinazolinone (1) with chloroacetylchloride in the presence of potassium hydroxide, and dry dimethylformamide (DMF) as a solvent to obtain the intermediate compound (2). This compound is reacted with different reagents to give four routes, the first route include direct reaction with substituted-2-aminobenzothiazole under certain conditions to give new compounds (3-9). The second route involved condensation compound (2) with 5-substituted-2-amino-1,3,4-oxadiazole in the presence of potassium carbonate anhydrous to give new compounds (10-13).while the third route inv

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Publication Date
Tue Sep 29 2020
Journal Name
Iraqi Journal Of Science
Smart Doctor: Performance of Supervised ART-I Artificial Neural Network for Breast Cancer Diagnoses
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Wisconsin Breast Cancer Dataset (WBCD) was employed to show the performance of the Adaptive Resonance Theory (ART), specifically the supervised ART-I Artificial Neural Network (ANN), to build a breast cancer diagnosis smart system. It was fed with different learning parameters and sets. The best result was achieved when the model was trained with 50% of the data and tested with the remaining 50%. Classification accuracy was compared to other artificial intelligence algorithms, which included fuzzy classifier, MLP-ANN, and SVM. We achieved the highest accuracy with such low learning/testing ratio.

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Synthesis of substituted (oxazepine, Diazepine, tetrazde) via Schiff Bases for 2- Aminobenzo Thaizole Derivatives
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This work includs synthesis of several Schiff bases by condensation of 6- methoxy – 2- amino benzothiazole with some aldehydes and ketones (2- hydroxyl benzaldehyde, 4- hydroxyl benzaldehyde, 4- N,N –dimethy amino acetophenone, benzophenone) to abtain schiff bases (1-5). These schiff bases were found to react with phthalate anhydride to give oxazepine derivatives (6-10) that were reacted with primary aromatic amines to give Diazepine derivatives (11-15). Besides, we prepared new tetrazole derivatives (16-20) from the reaction of the prepared Schiff bases with sodium azide in the prepared compounds that were characterized by physical properties, FT-IR and some of the 1H-NMR and 13C –NMR spectroscopy.

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Publication Date
Tue Dec 01 2020
Journal Name
Iraqi Journal Of Physics
Modifications to Accelerate the Iterative Algorithm for the Single Diode Model of PV Model
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This paper discussed the solution of an equivalent circuit of solar cell, where a single diode model is presented. The nonlinear equation of this model has suggested and analyzed an iterative algorithm, which work well for this equation with a suitable initial value for the iterative. The convergence of the proposed method is discussed. It is established that the algorithm has convergence of order six. The proposed algorithm is achieved with a various values of load resistance. Equation by means of equivalent circuit of a solar cell so all the determinations is achieved using Matlab in ambient temperature. The obtained results of this new method are given and the absolute errors is demonstrated.

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Adopting statistical methods for controlling the quality of drinking water to achieve customer satisfaction
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The current research aims to adopt production quality decisions as the most important decisions , because they are accompanied by customer satisfaction through monitoring the quality of drinking water in iraq which reach through the pipeline network associated with water treatment projects of Tigris and Euphrates rivers. One of the indicators of quality control was the drawing of the C-chart by specifying the central line and the upper and lower limit of the control and the diagnosis of whether the production system as a whole within the scope of quality control or not and determine the strength and significance of the correlation between the quantities of water And actual needs for customers , the research has reached a number o

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Publication Date
Sun Feb 25 2024
Journal Name
Baghdad Science Journal
An Improved Cuckoo Search Algorithm for Maximizing the Coverage Range of Wireless Sensor Networks
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The issue of increasing the range covered by a wireless sensor network with restricted sensors is addressed utilizing improved CS employing the PSO algorithm and opposition-based learning (ICS-PSO-OBL). At first, the iteration is carried out by updating the old solution dimension by dimension to achieve independent updating across the dimensions in the high-dimensional optimization problem. The PSO operator is then incorporated to lessen the preference random walk stage's imbalance between exploration and exploitation ability. Exceptional individuals are selected from the population using OBL to boost the chance of finding the optimal solution based on the fitness value. The ICS-PSO-OBL is used to maximize coverage in WSN by converting r

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Biogas Recovery from Anaerobic Co-Digestion of Poultry House Wastes for Clean Energy Production
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Anaerobic digestion is a technology widely used for treatment of organic waste for biogas production as a source for clean energy. In this study, poultry house wastes (PHW) material was examined as a source for biogas production. The effects of inoculum addition, pretreatment of the substrate, and temperature on the biogas production were taken into full consideration. Results revealed that the effect of inoculum addition was more significant than the alkaline pretreatment of raw waste materials. The biogas recovery from inoculated waste materials exceeds its production from wastes without inoculation by approximately 70% at mesophilic conditions. Whereby, the increase of biogas recovery from pretreated wastes was by 20% higher than its

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Publication Date
Sat Nov 10 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessment of Clinical Learning and Training Environment for Maternal and Child Health Nursing Students
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Objective: To assess the clinical learning environment and clinical training for students' in maternal and child
health nursing.
Methodology: A descriptive study was conducted on non probability sample (purposive) of (175) students' in
Nursing College/ University of Baghdad for the period of June 19th to July 18th 2013. A questionnaire was used as a
tool of data collection to fulfill with objective of the study and consisted of three parts, including demographic,
clinical learning environment and clinical training for students' in maternal and child health nursing. Descriptive
statistical analyses were used to analyze the data.
Results: The results of the study revealed that the 65.1% of student at age which ranged b

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