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alkej-282
Multi-Dimensional Angle of Arrival Estimation by Circular Phased Adaptive Array Antennas
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In this paper the use of a circular array antenna with adaptive system in conjunction with modified Linearly Constrained Minimum Variance Beam forming (LCMVB) algorithm is proposed to meet the requirement of Angle of Arrival (AOA) estimation in 2-D as well as the Signal to Noise Ratio (SNR) of estimated sources (Three Dimensional 3-D estimation), rather than interference cancelation as it is used for. The proposed system was simulated, tested and compared with the modified Multiple Signal Classification (MUSIC) technique for 2-D estimation. The results show the system has exhibited astonishing results for simultaneously estimating 3-D parameters with accuracy approximately equivalent to the MUSIC technique (for estimating elevation and azimuth angles), and it has privilege to estimate SNR for sources which are under the estimation process.

Finally, the proposed system needs less computational time and hardware complexity when it is compared with Eigen value decomposition techniques used by MUSIC technique. Also, it has cost effectiveness with respect to (3-D) active detecting means such as radars.

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Smoothing of Image using adaptive Lowpass Spatial Filtering
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Lowpass spatial filters are adopted to match the noise statistics of the degradation seeking
good quality smoothed images. This study imply different size and shape of smoothing
windows. The study shows that using a window square frame shape gives good quality
smoothing and at the same time preserving a certain level of high frequency components in
comparsion with standard smoothing filters.

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Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
DEO: A Dynamic Event Order Strategy for t-way Sequence Covering Array Test Data Generation
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Sequence covering array (SCA) generation is an active research area in recent years. Unlike the sequence-less covering arrays (CA), the order of sequence varies in the test case generation process. This paper reviews the state-of-the-art of the SCA strategies, earlier works reported that finding a minimal size of a test suite is considered as an NP-Hard problem. In addition, most of the existing strategies for SCA generation have a high order of complexity due to the generation of all combinatorial interactions by adopting one-test-at-a-time fashion. Reducing the complexity by adopting one-parameter- at-a-time for SCA generation is a challenging process. In addition, this reduction facilitates the supporting for a higher strength of

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
A Comparison of Parameters Estimation Methods for the Negative Binomial Regression Model under Multicollinearity Problem by Using Simulation
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This study discussed a biased estimator of the Negative Binomial Regression model known as (Liu Estimator), This estimate was used to reduce variance and overcome the problem Multicollinearity between explanatory variables, Some estimates were used such as Ridge Regression and Maximum Likelihood Estimators, This research aims at the theoretical comparisons between the new estimator (Liu Estimator) and the estimators

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Copper Nanoparticles Synthesized in Biopolymer Matrix and Their Application in Antibacterial Activity
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Copper is a cheaper alternative to various noble metals with a range of potential applications in the field of nanoscience and nanotechnology. However, copper nanoparticles have major limitations, which include rapid oxidation on exposure to air. Therefore, alternative pathways have been developed to synthesize metal nanoparticles in the presence of polymers and surfactants as stabilizers, and to form coatings on the surface of nanoparticles. These surfactants and polymeric ligands are made from petrochemicals which are non- renewable. As fossil resources are limited, finding renewable and biodegradable alternative is promising.The study aimed at preparing, characterizing and evaluating the antibacterial properties of copper nanoparticle

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Scopus (2)
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Publication Date
Fri May 01 2020
Journal Name
Journal Of Physics: Conference Series
New Approach for Solving Two Dimensional Spaces PDE
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Abstract<p>In this paper, new approach based on coupled Laplace transformation with decomposition method is proposed to solve type of partial differential equation. Then it’s used to find the accurate solution for heat equation with initial conditions. Four examples introduced to illustrate the accuracy, efficiency of suggested method. The practical results show the importance of suggested method for solve differential equations with high accuracy and easy implemented.</p>
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Scopus (19)
Crossref (7)
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Publication Date
Sun Dec 07 2008
Journal Name
Baghdad Science Journal
Three Dimensional MHD Simulationof Comet Hale-Bopp Tail
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The interaction between comet Hale-Bopp tail with the solar wind is investigated in the present paper using magneto-hydrodynamic (MHD) numerical simulation, which accounts for the presence of the interplanetary magnetic field (IMF). The simulation is based on three-dimensional Lax-Wendroff explicit scheme, providing second-order accuracy in space and time. The ions produced from the nucleus of the comet will add considerable effects on the microstructure of the solar wind, thus severely altering its physical properties. The present simulation focuses on careful analysis of these properties by means of simulating the behavior of the comet Hale-Bopp’s tail at 1 AU from the sun. These properties include the changes of the plasma density,

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Crossref
Publication Date
Sun Jan 01 2017
Journal Name
Journal Of Engineering
Adaptive Sliding Mode Controller for Servo Actuator System with Friction
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This paper addresses the use of adaptive sliding mode control for the servo actuator system with friction. The adaptive sliding mode control has several advantages over traditional sliding mode control method. Firstly, the magnitude of control effort is reduced to the minimal admissible level defined by the conditions for the sliding mode to exist. Secondly, the upper bounds of uncertainties are not required to be known in advance. Therefore, adaptive sliding mode control method can be effectively implemented. The numerical simulation via MATLAB 2014a for servo actuator system with friction is investigated to confirm the effectiveness of the proposed robust adaptive sliding mode control scheme. The results clarify, after

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
Learning for Scientific Culture by Using Interactive Whiteboard According to the Faculty of the University of Baghdad Viewpoint
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The progress of science in all its branches and levels made great civilized changes of
our societies in the present day, it's a result of the huge amount of knowledge, the increase of
number of students, and the increase of community awareness proportion of the importance of
education in schools and universities, it became necessary for us as educators to look at
science from another point of view based on the idea of scientific development of curricula
and teaching methods and means of education, and for the studying class environment as a
whole, by computer and internet use in education to the emergence of the term education
technology, which relies on the use of modern technology to provide educational content to<

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Publication Date
Sun Mar 30 2025
Journal Name
مجلة المستنصرية للدراسات العربية والدولية
أثر العمالة الاجنبية في ارتفاع مستويات البطالة في العراق
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ساهم توافد العمالة الأجنبية في تفاقم مشكلة البطالة في العراق الذي يستقبل المئات منهم سنوياً، في ظل تخرج آلاف الطلاب من الجامعات العراقية وانطلاقهم إلى سوق العمل بالتزامن مع عدم تنشيط دور القطاع الخاص بسبب التجاذبات السياسية والأوضاع الاقتصادية والأمنية التي أثرت بشكل كبير في تفعيله وجذب المستثمرين، وعلى رغم ذلك استمر توافد العمالة الأجنبية التي وجدت في العراق عبارة عن فرص ثمينة لا سيما في قطاع الخدمات، مما

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Publication Date
Tue May 10 2022
Journal Name
European Scholar Journal (esj)
MODELING AND COMPARISON OF CLOSED-LOOP AND OPENLOOP ADAPTIVE OPTICS SYSTEMS
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Astronomers have known since the invention of the telescope that atmospheric turbulence affects celestial images. So, in order to compensate for the atmospheric aberrations of the observed wavefront, an Adaptive Optics (AO) system has been introduced. The AO can be arranged into two systems: closedloop and open-loop systems. The aim of this paper is to model and compare the performance of both AO loop systems by using one of the most recent Adaptive Optics simulation tools, the Objected-Oriented Matlab Adaptive Optics (OOMAO). Then assess the performance of closed and open loop systems by their capabilities to compensate for wavefront aberrations and improve image quality, also their effect by the observed optical bands (near-infrared band

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