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Estimating Angle of Arrival (AOA) for Wideband Signal by Sensor Delay Line (SDL) and Tapped Delay Line (TDL) Processors
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Angle of arrival (AOA) estimation for wideband signal becomes more necessary for modern communication systems like Global System for Mobile (GSM), satellite, military applications and spread spectrum (frequency hopping and direct sequence). Most of the researchers are focusing on how to cancel the effects of signal bandwidth on AOA estimation performance by using a transversal filter (tap delay line) (TDL). Most of the researchers were using two elements array antenna to study these effects. In this research, a general case of proposed (M) array elements is used. A transversal filter (TDL) in phase adaptive array antenna system is used to calculate the optimum number of taps required to compensate these effect. The proposed system uses a phase adaptive array antenna in conjunction with LMS algorithm to work an angle of arrival (AOA) estimator for wideband signals rather than interference canceller. An alternative solution to compensate for the effect of signal bandwidth is proposed by using sensor delay line (SDL) instead of fixed delay unit since it has variable time sampling in the time domain and not fixed time delay, depending on the angle of arrival of received signals. The proposed system has the ability to estimate two parameters for received signals simultaneously (the output Signal to Noise Ratio (SNR) and AOA), unlike others systems which estimate AOA only. The comparison of the simulation results with Multiple Signal Classification (MUSIC) technique showed that the proposed system gives good results for estimating AOA and the output SNR for wideband signals. (SDL) processor shows better performance result than (TDL) processor. MUSIC technique with both (SDL) and (TDL) processors shows unacceptable results for estimating (AOA) for the wideband signal.  

 

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Studying Some Electrical Properties for ZnSe Films Prepared by Using the Thermal Evaporation Method in vacuum
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  Thin films of zinc selenide ZnSe have been prepared by using thermal evaporation method in vacuum with different thickness (1000 – 4000) Ao and a deposited on glass substrate and studying some electrical properties including the determination of A.C conductivity and real, imaginary parts of dielectric constant and tangent of loss angle. The result shows that increasing value of A.C conductivity with increasing thickness and temperature, and increasing capacitance value with increasing the temperature and decrease with increasing frequency . Real and imaginary parts of dielectric constant and tangent of loss angle decrease with increasing frequency

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Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Engineering
Permeability Estimation by Using the Modified and Conventional FZI Methods
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There many methods for estimation of permeability. In this Paper, permeability has been estimated by two methods. The conventional and modified methods are used to calculate flow zone indicator (FZI). The hydraulic flow unit (HU) was identified by FZI technique. This technique is effective in predicting the permeability in un-cored intervals/wells. HU is related with FZI and rock quality index (RQI). All available cores from 7 wells (Su -4, Su -5, Su -7, Su -8, Su -9, Su -12, and Su -14) were used to be database for HU classification. The plot of probability cumulative of FZI is used. The plot of core-derived probability FZI for both modified and conventional method which indicates 4 Hu (A, B, C and D) for Nahr Umr forma

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Publication Date
Wed Aug 26 2020
Journal Name
Iraqi Journal Of Agricultural Sciences
STIMULATION GROWTH AND YIELD OF POTATO BY BUTTONWOOD PRUNNING RESIDUES AND SPRAYING SEVERAL MICRONUTRIENTS
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This study was aimed to estimate the influence of Conocarpus erectus L. residues, and some micronutrients on growth and production of potato. This research was conducted at one of the fields of the College of Agricultural Engineering Sciences - University of Baghdad. The experiment was implemented using factorial arrangement (4X3X3) within randomized complete block design with three replicates. Conocarpus fertilizer was represented the first factor with three levels (7.5, 15, 30 ton.ha-1), which symbolized (C2, C3, C4). Mineral fertilizer as recommended dose as a control, which symbolized (C1). The second factor was foliar spraying with three levels of iron (0, 100, 200 mg.L-1), which symbolized (F0, F1, F2). The third factor is fol

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Publication Date
Thu Sep 13 2018
Journal Name
Baghdad Science Journal
An Efficient Numerical Method for Solving Volterra-Fredholm Integro-Differential Equations of Fractional Order by Using Shifted Jacobi-Spectral Collocation Method
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The aim of this article is to solve the Volterra-Fredholm integro-differential equations of fractional order numerically by using the shifted Jacobi polynomial collocation method. The Jacobi polynomial and collocation method properties are presented. This technique is used to convert the problem into the solution of linear algebraic equations. The fractional derivatives are considered in the Caputo sense. Numerical examples are given to show the accuracy and reliability of the proposed technique.

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Publication Date
Fri Sep 05 2014
Journal Name
Engineering And Technology Journal
New Method to Increase the Ability of the Water for Dissolving Total Salts in Soil by Using the Magnetism
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Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Palm dates as a source for isolation of Aspergillus niger to produce citric acid by submerged fermentation; kinetics study
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Abstract<p>The study discussed here deals with the isolation of Aspergillus niger from palm dates, the formal and the most famous fruit in Iraq, to test and qualify this fungus isolate for its ability to produce citric acid. Submerged fermentation technique was used in the fermentation process. A.niger isolated from “Zahdi” Palme dates was used in the study of the fermentation kinetics to get the production efficiency of citric acid. Kinetics of CA production via fermentation by A. niger S11 was evaluated within 432 h fermentation time and under submerged conditions of 11% (w/v) sucrose, 5% (v/v) inoculum size, pH 4, 30 °C and 150 rpm. The maximum citric acid produced was (37.116 g/l). Kine</p> ... Show More
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Publication Date
Wed Dec 12 2018
Journal Name
Iop Conference Series: Materials Science And Engineering
The performance of MnO<sub>2</sub>/graphite electrode for TOC removal from wastewater by indirect electrochemical oxidation process
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Electrochemical oxidation in the presence of sodium chloride used for removal of phenol and any other organic by products formed during the electrolysis by using MnO2/graphite electrode. The performance of the electrode was evaluated in terms fraction of phenol and the formed organic by products removed during the electrolysis process. The results showed that the electrochemical oxidation process was very effective in the removal of phenol and the other organics, where the removal percentage of phenol was 97.33%, and the final value of TOC was 6.985 ppm after 4 hours and by using a speed of rotation of the MnO2 electrode equal to 200 rpm.

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Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
Effect of immersion in chemical solution on the mechanical & physical properties for composite material reinforced by Nano alumina Particles
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In this research Epoxy resin was reinforced by nano alumina (AL2O3) particles in grain size(25-30 nm) with two weight ratios (2,4)% then compared with pure Epoxy. Four mechanical tests were performed on these materials include Hardness, flexural, impact & compression strengths before and after immersion in tap water and chemical solutions (CH3COOH) acid, (KOH) base at (0.5N) ,The diffusivity coefficients of all prepared samples were calculate after immersion in water and chemical solutions mentioned above , the results were showed that the Flexural, Impact & Hardness increase after addition the ceramic particles (AL2O3) while the immersion process results showed illustrated different values from sample to other.

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Publication Date
Fri Nov 09 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Screening Program for Idiopathic Scoliosis by Adam's Bending Forward Test of Prepubertal Children at Primary Schools in Baghdad City
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Objective: The study aimed to screen the prepubertal children for idiopathic scoliosis at earlier stages, and find
out the relationship between idiopathic scoliosis and demographic data such as age, sex, body mass index,
heavy backpacks, and heart & lung diseases.
Methodology: A descriptive study was conducted on screening program for prepubertal children in primary
schools at Baghdad city, starting from 24th of February to the end of October 2010. Non- probability
(purposive) sample of 510 prepubertal children were chosen from primary schools of both sides of Al-Karkh
and Al-Russafa sectors. Data was collected through a specially constructed questionnaire format include (24)
items multiple choice questions, and

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Publication Date
Wed Aug 13 2014
Journal Name
Journal Of Biotechnology Research Center
In Vivo Study for Measuring the Toxicity of Heat Stable Enterotoxin (a) Produced by Enterotoxigenic Escherichia coli in Mice
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This research was conducted to measure the safety of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli, through studying its toxic effect on mice since it showed a promising effect in reducing the proliferation of colorectal cancer cells. The cytogenetic effect was determined after giving five different doses (100, 200, 400, 800 and 1600)μg/Kg in comparison with negative (phosphate buffer saline / PBS) and positive (mitomycin C/ MMC, at doses of 2 and 5μg/Kg) controls on mouse bone marrow cells by employing the following parameters: mitotic index, chromosomal aberrations and micronucleus, also, the serum level of liver functional enzymes (GOT, GPT, ALP) was recorded. In addition, lethal dose 50 (LD 50) with cert

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