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Enhancement of Spectrum Sensing Performance via Cooperative Cognitive Radio ‎Networks at Low SNR
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     The inefficient use of spectrum is the key subject to overcome the upcoming spectrum crunch issue. This paper presents a study of performance of cooperative cognitive network via hard combining of decision fusion schemes. Simulation results presented different cooperative hard decision fusion schemes for cognitive network. The hard-decision fusion schemes provided different discriminations for detection levels. They also produced small values of Miss-Detection Probability at different values of Probability of False Alarm and adaptive threshold levels. The sensing performance was investigated under the influence of channel condition for proper operating conditions. An increase in the detection performance was achieved for cognitive users (secondary users) of the authorized unused dynamic spectrum holes (primary users) while operating in a very low signal-to-noise ratio  with the proper condition of minimum total error rate.

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Publication Date
Sun Jan 01 2023
Journal Name
Journal Of The Mechanical Behavior Of Materials
Simulation and assessment of water supply network for specified districts at Najaf Governorate
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Abstract<p>This study aims to simulate and assess the hydraulic characteristics and residual chlorine in the water supply network of a selected area in Al-Najaf City using WaterGEMS software. Field and laboratory work were conducted to measure the pressure heads and velocities, and water was sampled from different sites in the network and then tested to estimate chlorine residual. Records and field measurements were utilized to validate WaterGEMS software. Good agreement was obtained between the observed and predicted values of pressure with RMSE range between 0.09–0.17 and 0.08–0.09 for chlorine residual. The results of the analysis of water distribution systems (WDS) during maximum demand </p> ... Show More
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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Dispersion Parameters of Thermally Deposited Thin Lithium Floride Films at Different Annealing Temperatures
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Thin Lithium Fluoride films have been prepared by thermal evaporation technique on glass substrate under vacuum of about 10-5mbar. The thickness of the films was 4000±50Å. The effects of annealing temperatures on the optical properties and dispersion parameters have been studies. Transmittance spectra of the films indicate that the films have high transparency. The optical absorption studies reveal that the transition is direct with band gap value varied with the annealing temperatures. Also the refractive index dispersion curves obey to the single oscillator's model. The dispersion energy and single-oscillator energy varied with the annealing temperatures

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Publication Date
Wed Dec 25 2019
Journal Name
Journal Of Engineering
Effect of Tail Regulators on Euphrates River Flood Capacity at Al Nassiriyah City
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Euphrates River extends about 125 km within the study area located in Annassiriyah City, Dhi Qar Governorate, Iraq. The impact of the seven hydraulic structures on the discharge capacity of the Euphrates River needs to be considered. The main objectives of this research are to increase the discharge capacity of Euphrates River within Annassiriyah City during flood seasons and study the impact of these hydraulic structures on the river capacity by using HEC-RAS 5.0.3 software. Five scenarios were simulated to study the different current condition of Euphrates River within Annassiriyah City. Other additional four scenarios were implemented through river training to increase the river capacity to 1300 m³/s; it is the flood

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Publication Date
Thu Jul 01 2004
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DETECTION OF SUBSURFACE CAVITIES BY THE ELECTROMAGNETIC METHOD (Case Study at Haditha Area)
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Two EM techniques, terrain conductivity and VLF-Radiohm resistivity (using two
different instruments of Geonics EM 34-3 and EMI6R respectively) have been applied to
evaluate their ability in delineation and measuring the depth of shallow subsurface cavities
near Haditha city.
Thirty one survey traverses were achieved to distinguish the subsurface cavities in the
investigated area. Both EM techniques are found to be successfiul tools in study area.

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Publication Date
Sat Aug 01 2020
Journal Name
Journal Of Engineering
Computation of Critical Submergence Depth to Avoid Surface Vortices at Vertical Pumps Intakes
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The pumping station became widely used in many fields. Free surface vortices at intakes of pumps are not favorable. It may cause noise, excessive vibration, damage to the pumping structure, reduction in efficiency and flow for hydro-turbines, etc. One of the important problems encountered during the pump intake design is the depth of submergence and other design parameters to avoid strong free-surface vortices formation. This study aims to compute the critical submergence depth with some geometrical and hydraulic limitations by using Computational Fluid Dynamic (CFD) package. The mathematical model was validated with a laboratory model that had been conducted. The model of three intake pipes was investigated under five d

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Influences of the Cu Substitution at Hg Site in Hg1 - xCuxBa2Ca2Cu3O8+δ Superconductors
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The influences of the Cu substitution at Hg site in the HgOd layer, upon the
microstructure, Tc and oxygen content of Hg-1223 have been investigated. High
temperature superconductor with a nominal composition Hg1-xCuxBa2Ca2Cu3O8 + δ for
Cu ( 0 £ x £ 0.5) have been prepared by the two-steps solid state reaction method
under optimum conditions. XRD showed a tetragonal structure with a high ratio of
Hg-1223 superconductor phase. Tc enhancement has been determined with the Cu
concentration was is found to be Tc = 153 K for x = 0.3, while the oxygen content
observed variously with Cu concentration. Hg1-xCuxBa2Ca2Cu3O8+δ structure, oxygen
content and Tc behavior have been discussed.

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Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Relation & effect of Human resources management strategic with at work stress : Explorative study
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Abstract

The mine object for this research is determine the nature of the relation and effect between Human resources management strategic to less the  work stress , Human resources management strategic represent a set of procedures and practices to manage the human resources   at the organization. the stress of work effect on the performance of the human resources , al rasheed bank select to applied the qustioneer on the 32 person the work on the sebaa branch , using the qustioneer as a tool to collect data that is design  according some of the standards and make the validity and stability. to analyses this data by using spss for computation " percentage , mean , standard , deriation

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Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Global Pharma Technology
Assessment of heavy metals in some ground water wells at Baghdad City/Iraq
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Occurrence the heavy metals in water is one of the most important concerns. may cause savior health problems. In this work we made an attempt to know the quantity of six heavy metals in groundwater in different locations of Baghdad city. Examinations were made on groundwater of the review region to assess the heavy metals. Groundwater samples were gathered and analyzed utilizing Atomic Absorption Spectrophotometer for their Manganese, Iron, Zinc, Cadmium, Copper and Lead content and their levels compared with World Health Organization (WHO) specified maximum contaminant level. In order to accomplish this, water samples were obtained from 10 randomly selected wells in the region, in February and August, 2016. The study showed that the ground

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Publication Date
Mon Sep 13 2021
Journal Name
Eureka: Physics And Engineering
A numerical study to improve the position and angle of the producer gas injector inside the intake manifold to minimize emissions and efficiency enhancement of a bi engine
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To develop a petrol engine so that it works under the bi-engine pattern (producer gas-petrol) without any additional engine modifications, a single-point injection method inside the intake manifold is a simple and inexpensive method. Still, it leads to poor mixing performance between the air and producer gas. This deficiency can cause unsatisfactory engine performance and high exhaust emissions. In order to improve the mixing inside the intake manifold, nine separate cases were modelled to evaluate the impact of the position and angle orientation inside the intake manifold on the uniformity and spread of the mixture under AFR=2.07. A petrol engine (1.6 L), the maximum engine speed (8000 rpm), and bi-engine mode (petrol-producer ga

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Publication Date
Tue Dec 06 2022
Journal Name
Iraqi National Journal Of Nursing Specialties
Quality of Life of Children age from (8- lessthan13) years with Acute Lymphocytic Leukemia Undergoing Chemotherapy at Hematology Center in Medical City
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Objective (s): To assess the QoL of children age from (8- lessthan13) years with acute lymphocytic leukemia undergoing chemotherapy and to find out the relationship between the QoL of children with acute lymphocytic leukemia and their illness history.

Methodology:  A descriptive study included (40) children with acute lymphocytic leukemia who were ranged between (8 - less than 13 years) at the Hematology Center in Medical City for the period from 4th March 2021 to 1st September 2021. The sample was non-probability (purposive) sample of children (male and female). A questionnaire designed with 2 main parts was used. The first part focused on sociodemographic characterist

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