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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
Thu Oct 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Investigating the Structural and Magnetic Properties of Nickel Oxide Nanoparticles Prepared by Precipitation Method
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This work used the deposition method to synthesize nickel oxide nanoparticles. The materials mainly used in this study were nickel sulfate hexahydrate (as a precursor) and NaOH (as a precipitant). The properties of the nanopowder were characterized by XRD, FE-SEM, EDX, and VSM. The obtained results confirmed the presence of nickel oxide nanoparticles with a face-centered cubic (FCC) structure with a lattice constant (a=4.17834 Å). Scherer and Williamson-Hall equations were used to calculate the crystallite size of about (30.5-35.5) nm. The FE-SEM images showed that the particle shape had a ball-like appearance with a uniform and homogeneous distribution and confirmed that the particles were within the nanoscale. The presence of oxygen a

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Publication Date
Thu Apr 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Solution of 2nd Order Nonlinear Three-Point Boundary Value Problems By Semi-Analytic Technique
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    In this paper, we present new algorithm for the solution of the second order nonlinear three-point boundary value problem with suitable multi boundary conditions. The algorithm is based on the semi-analytic technique and the solutions which are calculated in the form of a rapid convergent series. It is observed that the method gives more realistic series solution that converges very rapidly in physical problems. Illustrative examples are provided to demonstrate the efficiency and simplicity of the proposed method in solving this type of three point boundary value problems.

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Quality Evaluation of Al-Rasheed Ready Concrete Mixture Plant By Using Six Sigma Approach
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The objective of this research work is to evaluate the quality of central concrete plant of Al-Rasheed Company by using Six Sigma approach which is a measure of quality that strives for near elimination of defects using the statistical methods to improve outputs that are critical to customers. The fundamental objective of Six Sigma methodology is the implementation of a measurement-based strategy that focuses on process improvement and variation reduction to reach delighting customers, and then suggesting an improvement system to improve the production of concrete in Al-Rasheed State Contracting Construction Company.
A field survey includes two parts (open and close questionnaire) that aimed to get the data and information required f

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Publication Date
Wed May 29 2019
Journal Name
Iraqi Journal Of Physics
Synthesis and characterization of Iron tungstate oxide films by advanced controlled spray pyrolysis technique
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For the first time Iron tungstate semiconductor oxides films (FeWO4) was successfully synthesized simply by advanced controlled chemical spray pyrolysis technique, via employed double nozzle instead of single nozzle using tungstic acid and iron nitrate solutions at three different compositions and spray separately at same time on heated silicone (n-type) substrate at 600 °C, followed by annealing treatment for one hour at 500 °C. The crystal structure, microstructure and morphology properties of prepared films were studied by X-ray diffraction analysis (XRD), electron Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) respectively. According to characterization techniques, a material of well-crystallized monoclinic ph

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Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Modeling and Simulation of Cadmium Removal from the Groundwater by Permeable Reactive Barrier Technology
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The removal of cadmium ions from simulated groundwater by zeolite permeable reactive barrier was investigated. Batch tests have been performed to characterize the equilibrium sorption properties of the zeolite in cadmium-containing aqueous solutions. Many operating parameters such as contact time, initial pH of solution, initial concentration, resin dosage and agitation speed were investigated. The best values of these parameters that will achieved removal efficiency of cadmium (=99.5%) were 60 min, 6.5, 50 mg/L, 0.25 g/100 ml and 270 rpm respectively. A 1D explicit finite difference model has been developed to describe pollutant transport within a groundwater taking the pollutant sorption on the permeable reactive barrier (PRB), which i

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Sorption of Lead, Zinc and Copper from Simulated Wastewater by Amberlite Ir-120 Resin
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The presence of heavy metals in the environment is major concern due to their toxicity. In the present study a strong acid cation exchange resin, Amberlite IR 120 was used for the removal of lead, zinc and copper from simulated wastewater. The optimum conditions were determined in a batch system of concentration 100 mg/L, pH range between 1 and 8, contact time between 5 and 120 minutes, and amount of adsorbent was from 0.05 to 0.45 g/100 ml. A constant stirring speed, 180 rpm, was chosen during all of the experiments. The optimum conditions were found to be pH of 4 for copper and lead and pH 6 for zinc, contact time of 60 min and 0.35 g of adsorbent. Three different temperatures (25, 40 and 60°C) were selected to investigate the effect

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Removal of Copper Ions onto Walnut Shells by Using Batch and Continuous Fluidized Bed
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An agricultural waste (walnut shell) was undertaken to remove Cu(II) from aqueous solutions in batch and continuous fluidized bed processes. Walnut shell was found to be effective in batch reaching 75.55% at 20 and 200 rpm, when pH of the solution adjusted to 7. The equilibrium was achieved after 6 h of contacting time. The maximum uptake was 11.94mg/g. The isotherm models indicated that the highest determination coefficient belongs to Langmuir model. Cu (II) uptake process in kinetic rate model followed the pseudo-second-order with determination coefficient of 0.9972. More than 95% of the Cu(II) were adsorbed on the walnut shells within 6 h at optimum agitation speed of 800 rpm. The main functional groups responsible for biosorption of

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Publication Date
Fri Dec 29 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Structure and Optical Properties of BhSe3 Thin Films Prepared by Chemical Bath Deposition Method
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Thin films of  BhSe3  have being deposited on glass substrates of

about 80 - 172 ± 14 nm thickness from an aqueous solution bath at temperature 293 K for period 0.5 to 6.0 hours  using alchemical bath deposition method .

The  films  are  characterized   by  X-ray  diffraction,     X-ray

florescent techniques and optical transmittance spectra measurements in the rang 350 - 400 nm at 293 K. And shows that as deposited  films are amorphous and a  transition to polycrystalline state has taken place after  annealing  them  at  373  K,  for  30  minutes,  But  they  will  be dan1aged

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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
PROJECT MANAGEMENT OF BALAD`S MAJOR SEWERAGE SYSTEM BY USING THE GOAL PROGRAMMING METHOD
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Abstract

          The project of balad's major sewerage system is one of the biggest projects who is still in progress in salahulddin province provincial - development plan that was approved in 2013 . This project works in two parts ; the 1st is installing the sewerage networks (both of heavy sewerage & rain sewerage) and the 2nd is installing the     life – off units (for heavy sewerage & rain sewerage , as well) . the directorate of salahuiddin is aiming that at end of construction it will be able to provide services for four residential quarters , one of the main challenges that project's  management  experience is how to achieve thes

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Select the optimal project by using two methods of analytic hierarchy and goal programming
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      The aim of this research is to solve a real problem in the Department of Economy and Investment in the Martyrs establishment, which is the selection of the optimal project through specific criteria by experts in the same department using a combined mathematical model for the two methods of analytic hierarchy process and goal programming, where a mathematical model for goal programming was built that takes into consideration the priorities of the goal criteria by the decision-maker to reach the best solution that meets all the objectives, whose importance was determined by the hierarchical analysis process. The most important result of this research is the selection of the second pro

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