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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 Dec 31 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Simulation the Radiation Zone of Al-Mussaib Power Plant by Using Monte Carlo Method
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The temperature distributions are to be evaluated for the furnace of Al-Mussaib power plant. Monte Carlo simulation procedure is used to evaluate the radiation heat transfer inside the furnace, where the radiative transfer is the most important process occurring there. Weighted sum of gray-gases model is used to evaluate the radiative properties of the non gray gas in the enclosure. The energy balance equations are applied for each gas, and surface zones, and by solving these equations, both the temperature, and the heat flux are found.

   Good degree of accuracy has been obtained, when comparing the results obtained by the simulation with the data of the designing company, and the data obtained by the zonal method. In

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Publication Date
Thu Nov 02 2023
Journal Name
Journal Of Engineering
Numerical Simulation of the Thermal Performance of a Tubular Solar Air Heater
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In this work, a flat-plate solar air heater (FSAH) and a tubular solar air heater (TSAH) were designed and tested numerically. The work investigates the effect of increasing the contact area between the flowing air and the absorber surface of each heater and predicts the expected results before the fabrication of the experimental rig. Three-dimensional two models were designed and simulated by the ANSYS-FLUENT 16 Program. The solar irradiation and ambient air temperature were measured experimentally on December 1st 2022, at the weather conditions of Baghdad City- Iraq, at three air mass flow rates, 0.012 kg/s, 0.032 kg/s, and 0.052 kg/s. The numerical results showed the advantage in the thermal performance of

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Publication Date
Sat Aug 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Simulation of Sediment Transport in the Upper Reach of Al-Gharraf River
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Abstract<p>For the past few years, the sediment began to accumulate in Al-Gharraf River which reduces the flow capacity of the River. In the present research, a numerical model was developed using Hec-Ras software, version 5.0.4. to simulate the flow and sediment transport in the upper reach of the river. The hydrological and cross-section data measured by the Ministry of Water Resources, for the reach located between Kut and Hai cities and having a length of 58200 m, was used to perform calibration and verification of the model. Moreover, field sampling of suspended and bed loads was gathered for five months starting from 7/2/2019, and laboratory tests of samples were conducted to be used as in</p> ... Show More
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Publication Date
Sun Mar 01 2020
Journal Name
Baghdad Science Journal
Discussing Fuzzy Reliability Estimators of Function of Mixed Probability Distribution By Simulation
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This paper deals  with constructing mixed probability distribution  from exponential with scale parameter (β) and also Gamma distribution with (2,β), and the mixed proportions are (  .first of all, the probability density function (p.d.f) and also cumulative distribution function (c.d.f) and also the reliability function are obtained. The parameters of mixed distribution, ( ,β)  are estimated by three different methods, which are  maximum likelihood, and  Moments method,as well proposed method (Differential Least Square Method)(DLSM).The comparison is done using simulation procedure, and all the results are explained in tables.

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Publication Date
Thu Mar 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Simulation Study of Sputtering Yield of Zn Target Bombarded By Xenon Ions
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    Using a reduction of TRIM simulation data, the sputtering yield behaviour of Zinc target bombard by heavy Xenon ions plasma is studied. The sputtering yield as a function of Zinc layer width, Xenon ion number, energy of ions, and the angle of ion incidence are calculated and illustrated graphically. The corresponding energy loss due to ionization, vacancies and phonons, are graphically shown and discussed. Further, we fit the calculations and expressions for fitted curves are presented with its coefficients.

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Publication Date
Mon Aug 01 2016
Journal Name
Arpn Journal Of Engineering And Applied Sciences
SURVEY ON VANET TECHNOLOGIES AND SIMULATION MODELS
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Vehicular ad hoc network (VANET) is a distinctive form of Mobile Ad hoc Network (MANET) that has attracted increasing research attention recently. The purpose of this study is to comprehensively investigate the elements constituting a VANET system and to address several challenges that have to be overcome to enable a reliable wireless communications within a vehicular environment. Furthermore, the study undertakes a survey of the taxonomy of existing VANET routing protocols, with particular emphasis on the strengths and limitations of these protocols in order to help solve VANET routing issues. Moreover, as mobile users demand constant network access regardless of their location, this study seeks to evaluate various mobility models for vehi

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
Fuzzy Bridge Regression Model Estimating via Simulation
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      The main problem when dealing with fuzzy data variables is that it cannot be formed by a model that represents the data through the method of Fuzzy Least Squares Estimator (FLSE) which gives false estimates of the invalidity of the method in the case of the existence of the problem of multicollinearity. To overcome this problem, the Fuzzy Bridge Regression Estimator (FBRE) Method was relied upon to estimate a fuzzy linear regression model by triangular fuzzy numbers. Moreover, the detection of the problem of multicollinearity in the fuzzy data can be done by using Variance Inflation Factor when the inputs variable of the model crisp, output variable, and parameters are fuzzed. The results were compared usin

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Publication Date
Wed Apr 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Simulation and Analysis the Effect of the Lorentz Force in a Free Electron Laser
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Due to the scientific and technical development in the free electron laser devices and the accompanying industrial and technological progress in various fields of civil and military life, it became necessary to expand the understanding of the mechanism of interaction of electrons (as an effective medium) with the magnetic field that they pass through to form coherent photons.

    In this paper, the Lorentz force effect is simulated and analysed. The results showed that the Lorentz force originates from the magnetic field, making the electron move through it oscillate. This sinusoidal motion of the electron causes it to emit two photons for every electron wavelength. It has been concluded that the electron velocity directly affe

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Publication Date
Thu Jan 23 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Exploitation decision and impact factors in improvement in stock exchange markets proportion investment small
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The purpose of the search definition on factors superior this whoever  impact on the improvement the exploitation  decision this  detect on stock exchange markets  assumption , and using  questioners to data accumulate  and the Iraq market of financial papers  battleground to search annoy chose the eyeball extension (47) peoples from peoples employees on the market , and using the bought statistic program (SPSS) on input and analysis search  data , and machinate the search outputs to their group of factors internal and external which impact on exploitation  decision on financial papers markets , and the search commend on necessary rise  the incumbency direction  in the stock exchange

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Publication Date
Thu Mar 01 2018
Journal Name
Asian Journal Of Multidisciplinary Studies
Entrepreneurial mindset and aspiration as critical success factor for small business performance in Iraq
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The aim of this research is to examine the relationship between entrepreneurial mindset and aspiration and small business performance Baghdad, Iraq. This study proposed a quantitative analysis in which entrepreneurial mindset and aspiration is a critical success factor of small business in Iraq. The method employed in the collection of data was by the means of self-administered questionnaire which was filled and completed by small business owners randomly selected from a sampling frame of registered small businesses. The questionnaire was adapted from the study of Davis, Halls & Mayer (2015) and Abdel-Maksoud, Asada & Nakagawa (2008) which was used to measure entrepreneurial mindset and aspiration using a ten items scale and small business

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