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Simulation of Small Radio Telescope Antenna Parameters at Frequency of 1.42 GHz
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The paper presents an overview of theoretical aspects of small radio telescope antenna parameters. The basic parameters include antenna beamwidth, antenna gain, aperture efficiency, and antenna temperature. These parameters should be carefully studied since they have vital effects on astronomical radio observations. The simulations of antenna parameters were carried out to assess the capability and the efficiency of small radio telescopes to observe a point source at a specific frequency. Two-dimensional numerical simulations of a uniform circular aperture antenna are implemented at different radii. The small diameter values are chosen to be varied between (1-10) m. This study focuses on a small radio telescope with a diameter of 3 m since this telescope is very common in the world. The simulated results of this study illustrated that the power pattern of a 3 m antenna has a half-power beamwidth of approximately 5 degrees. Also, the maximum peak antenna temperature is estimated to be more than 3000 K. All of these results were in good agreement with observations of the neutral hydrogen spectral line at the frequency of 1.42 GHz using a small radio telescope.

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
The role credit guarantee companies to bank guarantee in the financing of small and medium enterprises
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       It has become clear to see the role of the small and medium enterprises in the economy, and for the continuity of these projects it is necessary to supply finance from the banks, How ever the latter suffers risk of lending.                                                                          

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Publication Date
Mon Oct 01 2018
Journal Name
Ieee Transactions On Network Science And Engineering
A Resource Allocation Mechanism for Cloud Radio Access Network Based on Cell Differentiation and Integration Concept
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Publication Date
Sat Jun 01 2019
Journal Name
2019 International Symposium On Networks, Computers And Communications (isncc)
An Interference Mitigation Scheme for Millimetre Wave Heterogeneous Cloud Radio Access Network with Dynamic RRH Clustering
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Publication Date
Sun Jan 01 2012
Journal Name
Al-taqni Journal
The Frequency of Urinary Tract Infection According to the Age and Sex in Some of Iraqi Children.
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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Large Eddy Simulation in Duct Flow
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In this paper, the problem of developing turbulent flow in rectangular duct is investigated by obtaining numerical results of the velocity profiles in duct by using large eddy simulation model in two dimensions with different Reynolds numbers, filter equations and mesh sizes. Reynolds numbers range from (11,000) to (110,000) for velocities (1 m/sec) to (50 m/sec) with (56×56), (76×76) and (96×96) mesh sizes with different filter equations. The numerical results of the large eddy simulation model are compared with k-ε model and analytic velocity distribution and validated with experimental data of other researcher. The large eddy simulation model has a good agreement with experimental data for high Reynolds number with the first, seco

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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Magnetic solar surface flux transport simulation
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In this paper, the solar surface magnetic flux transport has been simulated by solving the diffusion–advection equation utilizing numerical explicit and implicit methods in 2Dsurface. The simulation was used to study the effect of bipolar tilted angle on the solar flux distribution with time. The results show that the tilted angle controls the magnetic distribution location on the sun’s surface, especially if we know that the sun’s surface velocity distribution is a dependent location. Therefore, the tilted angle parameter has distribution influence.

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Publication Date
Thu Sep 01 2016
Journal Name
Physica Medica
Quantitative analysis of sentinel lymph node detection using a novel small field of view hybrid gamma camera (HGC)
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Introduction The Hybrid Gamma Camera (HGC) is being developed to enhance the localisation of radiopharmaceutical uptake in targeted tissues during surgical procedures such as sentinel lymph node (SLN) biopsy. Purpose To assess the capability of the HGC, a lymph-node-contrast (LNC) phantom was constructed for an evaluative study simulating medical scenarios of varying radioactivity concentration and SLN size. Materials and methods The phantom was constructed using two methyl methacrylate PMMA plates (8 mm thick). The SLNs were simulated by drilling circular wells of diameters ranging between 10 mm and 2.5 mm (16 wells in total) in one plate. These simulated SLNs were placed underneath scattering material with thicknesses ranging between 5 mm

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Publication Date
Sun Mar 01 2015
Journal Name
Computer Systems Science & Engineering
Parameters' fine tuning of differential evolution algorithm
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Most heuristic search method's performances are dependent on parameter choices. These parameter settings govern how new candidate solutions are generated and then applied by the algorithm. They essentially play a key role in determining the quality of the solution obtained and the efficiency of the search. Their fine-tuning techniques are still an on-going research area. Differential Evolution (DE) algorithm is a very powerful optimization method and has become popular in many fields. Based on the prolonged research work on DE, it is now arguably one of the most outstanding stochastic optimization algorithms for real-parameter optimization. One reason for its popularity is its widely appreciated property of having only a small number of par

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Dispersion Parameters of Copper Sulphate Doped PMMA
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Films of PMMA and copper sulphate doped PMMA have been prepared by casting method. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm in order to calculate, single oscillator energy, dispersion energy, average oscillator strength, the refractive index at infinite wavelength, M-1 and M -3 moments of the optical spectra, it was found that all these parameters were effected by doping.

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Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
HLA-DRB1*03 And DRB1*15 Frequency In Helicobacter Pylori Superficial Gastritis
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Background: Background: Helicobacter pylori is an important gastrointestinal bacteria related to the development of  superficial atrophic gastritis, peptic ulcer and gastric cancer. Human leukocyte antigens (HLA) may play an important roles in host immune responses to H pylori antigens.

Aim of the study: to investigate the association between HLA-DRB1 genotypes and superficial gastritis with H. pylori infection in an Iraqi patients.

Patients and methods: Sixty patients with superficial gastritis and 100 individuals with apparently normal results after endoscopic examination were recruited from Al-Kindy Teaching Hospital - G

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