Preferred Language
Articles
/
ijp-726
Simulation of Small Radio Telescope Antenna Parameters at Frequency of 1.42 GHz
...Show More Authors

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.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jun 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Some Robust methods for Estimates the power Spectrum in ARMA Models Simulation Study
...Show More Authors

Abstract:

Robust statistics Known as, resistance to errors caused by deviation from the stability hypotheses of the statistical operations (Reasonable, Approximately Met, Asymptotically Unbiased, Reasonably Small Bias, Efficient ) in the data selected in a wide range of probability distributions whether they follow a normal distribution or a mixture of other distributions deviations different standard .

power spectrum function lead to, President role in the analysis of Stationary random processes, form stable random variables organized according to time, may be discrete random variables or continuous. It can be described by measuring its total capacity as function in frequency.

<

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Between Tree regression (TR), and Negative binomial regression (NBR) by Using Simulation.
...Show More Authors

            In this paper, the process of comparison between the tree regression model and the negative binomial regression. As these models included two types of statistical methods represented by the first type "non parameter statistic" which is the tree regression that aims to divide the data set into subgroups, and the second type is the "parameter statistic" of negative binomial regression, which is usually used when dealing with medical data, especially when dealing with large sample sizes. Comparison of these methods according to the average mean squares error (MSE) and using the simulation of the experiment and taking different sample

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 01 2021
Journal Name
International Journal Of Statistical
Evaluating the performance of introduced varieties of maize (Zea Mays L.) and estimating some genetic parameters
...Show More Authors

Scopus (12)
Scopus
Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Effect of Aqueous Extract of Fig (Ficus carica) Fruit on Some Hematological Parameters in Female Rabbits
...Show More Authors

The effect of the aqueous extract of fig (Ficus carica) fruit was studied by using different concentrations of this fruit (15, 20 and 25 mg/kg of body weight) on some hematological parameters (hemoglobin concentration, packed cell volume, white blood cell count and platelets count) in female rabbits. Twenty female rabbits were randomly divided into four groups (five animals in each group). Three groups were dosed with the concentrations mentioned above, while the last was administered with distilled water and considered as control group. These animals were orally dosed by aqueous extract using a micropipette. The results showed that there was a significant (P<0.05) increase in hemoglobin concentration and packed cell volume means for all

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
A Review of the Stereo lithography 3D Printing Process and the Effect of Parameters on Quality
...Show More Authors

Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA type b

... Show More
View Publication Preview PDF
Scopus (16)
Crossref (14)
Scopus Crossref
Publication Date
Sat Apr 01 2023
Journal Name
Heliyon
Application of solar photo-electro-Fenton technology to petroleum refinery wastewater degradation: Optimization of operational parameters
...Show More Authors

View Publication
Scopus (17)
Crossref (14)
Scopus Clarivate Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
A Review of the Stereo lithography 3D Printing Process and the Effect of Parameters on Quality
...Show More Authors

Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA t

... Show More
Scopus (16)
Crossref (14)
Scopus Crossref
Publication Date
Fri Dec 22 2023
Journal Name
Eastern-european Journal Of Enterprise Technologies
Evaluating the impact of structure parameters on the acoustic performance of an exhaust muffler with shells
...Show More Authors

Recently, environmental noise has arisen from various sources, such as those from exhaust mufflers of combustion engines found in cars, trucks, or power generators, which produce significant noise during their operation. Controlling the radiated noise from these mufflers is a major factor in improving acoustic comfort and minimizing the impact on the surrounding communities. Numerous research has been presented for this reason by modification of the internal structure of the exhaust muffler. The main objective of this work is to reduce the noise level emitted from exhaust mufflers. This can be achieved by adjusting structure parameters to attenuate the surrounding environment's radiated noise. Analysis of pressure-wave propagation h

... Show More
View Publication
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Sat Jun 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Combined Effect of Some Internal Ballisting Parameters on the Pressure Behavior of Solid Propellant Rocket Motor
...Show More Authors

View Publication Preview PDF
Publication Date
Fri Mar 03 2023
Journal Name
Iraqi Journal Of Science
The effect of background argon gas pressure on parameters of plasma produced by Dc- glow discharge
...Show More Authors

Non-thermal plasmas have become popular as plasma technology has advanced in various fields, including waste management, aerospace technology, and medicinal applications. They can be used to replace combustion fuels in stationary hall motors and need little effort to keep running for longer periods of time. To improve overall system performance, non-reactive gases such as )Xe, Ar, and Kr) are utilized in pure or mixed form to generate plasma. Since DC glow discharge is a fundamental topic of importance, these gases have been researched. The paper concentrates on 2-D modeling and simulation. DC glow-discharge tubes are utilized with argon gas to create plasma and learn about its properties. The magnitude of the electron density, increases wi

... Show More