Preferred Language
Articles
/
BhiwJpcBVTCNdQwCh5Yt
Numerical Simulation of Solar Granulation Dynamics Using Optical Correction Techniques
...Show More Authors

High-resolution imaging of celestial bodies, especially the sun, is essential for understanding dynamic phenomena and surface details. However, the Earth's atmospheric turbulence distorts the incoming light wavefront, which poses a challenge for accurate solar imaging. Solar granulation, the formation of granules and intergranular lanes on the sun's surface, is important for studying solar activity. This paper investigates the impact of atmospheric turbulence-induced wavefront distortions on solar granule imaging and evaluates, both visually and statistically, the effectiveness of Zonal Adaptive Optics (AO) systems in correcting these distortions. Utilizing cellular automata for granulation modelling and Zonal AO correction methods, the study aims to understand system behavior under varying atmospheric turbulence conditions and provide recommendations for Zonal AO system enhancement for solar observations. Performance metrics, including Strehl Ratio, Correction Stability, Root Mean Squared Error (RMSE), and Correction Rate, were used to assess system performance under varying turbulence levels. However, challenges arise with increasing turbulence strength, impacting correction precision, stability, and speed. The results showed the weakness of the Zonal AO in treating high distortions in wavefront, as is evident by the decreases in Strehl Ratio values from 0.98 to 0.085 for disturbance strength values from 0.2 to 1, respectively.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Aug 21 2023
Journal Name
Communications In Mathematical Biology And Neuroscience
New techniques to estimate the solution of autonomous system
...Show More Authors

This research aims to solve the nonlinear model formulated in a system of differential equations with an initial value problem (IVP) represented in COVID-19 mathematical epidemiology model as an application using new approach: Approximate Shrunken are proposed to solve such model under investigation, which combines classic numerical method and numerical simulation techniques in an effective statistical form which is shrunken estimation formula. Two numerical simulation methods are used firstly to solve this model: Mean Monte Carlo Runge-Kutta and Mean Latin Hypercube Runge-Kutta Methods. Then two approximate simulation methods are proposed to solve the current study. The results of the proposed approximate shrunken methods and the numerical

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Thu Dec 31 2020
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
SIMULATION AND MODELING OF HYDRO CRACKING REACTR TO REDUCE POLLUTION CAUSED BY REFINERIES: SIMULATION AND MODELING OF HYDRO CRACKING REACTR TO REDUCE POLLUTION CAUSED BY REFINERIES
...Show More Authors

Hydro cracking of heavy oil is used in refinery to produce invaluable products. In this research, a model of hydro cracking reactor has been used to study the behavior of heavy oil in hydro cracking under the conditions recommended by literature in terms lumping of feed and products. The lumping scheme is based on five lumps include: heavy oil, vacuum oil, distillates, naphtha and gases. The first order kinetics was assumed for the conversion in the model and the system is modeled as an isothermal tubular reactor. MATLAB 6.1 was used to solve the model for a five lump scheme for different values of feed velocity, and temperature.

View Publication Preview PDF
Publication Date
Wed Jul 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Experimental and Numerical Comparison of Prestressed Perforated Concrete Rafters of Different Configurations
...Show More Authors
Abstract<p>This paper demonstrates an experimental and numerical study aimed to compare the influence of openings of different configurations on the flexural behavior of prestressed concrete rafters. The experimental program consisted of testing six simply supported prestressed concrete rafters; 5 rafters are perforated, and the other one is solid as a reference. All rafters were tested under monotonic midpoint load. The variable which has been investigated in this work was the opening’s configuration (quadrilateral or circular) with the same upper and lower chords depths. The results indicate improvement in the beam flexural behavior using the circular openings compared to the quadrilateral o</p> ... Show More
View Publication Preview PDF
Scopus (5)
Crossref (4)
Scopus Crossref
Publication Date
Mon Oct 02 2023
Journal Name
Journal Of Engineering
Numerical Analysis of the Stability of Bridge Foundation Pile under Earthquakes Effect
...Show More Authors

This study was chosen because of the entry of our regions into the seismic zone recently, where Diyala governorate was hit by the Halabja earthquake in 2017 by 7.3Mw. Therefore, the impact of earthquakes will be studied on the AL-Mafraq bridge foundations piles located in Iraq- east of Baghdad in Diyala Governorate and the extent of its resistance to the Halabjah, EL-Centro, and Kobe earthquakes with acceleration 0.1g, 0.34g, and 0.58g respectively. After modeling and performing the analysis by using Midas Gts-Nx software, the settlement (mm) results at nine nodes (four nodes for the pile cap and five nodes for the piles) were obtained for each of Halabjah, EL-Centro, and Kobe earthquakes to know the resistance of the br

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Numerical Computations of Transonic Critical Aerodynamic Behavior of a Realistic Artillery Projectile
...Show More Authors

The determination of aerodynamic coefficients by shell designers is a critical step in the development of any projectile design. Of particular interest is the determination of the aerodynamic coefficients at transonic speeds. It is in this speed regime that the critical aerodynamic behavior occurs and a rapid change in the aerodynamic coefficients is observed. Two-dimensional, transonic, flow field computations over projectiles have been made using Euler equations which were used for solution with no special treatment required. In this work a solution algorithm is based on finite difference MacCormack’s technique for solving mixed subsonic-supersonic flow problem. Details of the asymmetrically located shock waves on the projectiles hav

... Show More
View Publication Preview PDF
Publication Date
Wed Jun 01 2022
Journal Name
Journal Of Engineering
Numerical Investigation of Aerodynamic Characteristics of Supercritical RAE2822 Airfoil with Gurney Flap
...Show More Authors

Gurney flap (GF) is well-known as one of the most attractive plain flaps because of the simple configuration and effectiveness in improving the lift of the airfoil. Many studies were conducted, but the effects of GF on the various airfoil types need to be further investigated. This study aimed to clarify the effect of GF in the case of the supercritical airfoil RAE2822. This research includes a steady, two-dimensional computational investigation carried out on the supercritical airfoil type RAE-2822 to analyze Gurney flap (GF) effects on the aerodynamic characteristics of this type of airfoil utilizing the Spalart-Allmaras turbulence model within the commercial software Fluent. The airfoil with the Gurney flap was analyz

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Oct 18 2018
Journal Name
Al–bahith Al–a'alami
Modalities and Methodological Techniques in Media Studies
...Show More Authors

There have been many writings and discussions that dealt with the details and interpretation of the research methods and the identification of the methods and methodological methods used by researchers and writers as they deal with research topics and problems in all fields of natural and human sciences. But we noticed that the movement of science and its knowledge and development requires the identification of suitable tools and methodological methods appropriate for each type of science. In other words, attempts should be established to build appropriate methodological tools for human and cognitive activity that can be referred to as a specific science that sets out certain paths of the human sciences which is certainly the ori

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
The Satellite Images Matching and Mosaic Techniques
...Show More Authors

      The Matching and Mosaic of the satellite imagery play an essential role in many remote sensing and image processing projects. These techniques must be required in a particular step in the project, such as remotely change detection applications and the study of large regions of interest. The matching and mosaic methods depend on many image parameters such as pixel values in the two or more images, projection system associated with the header files, and spatial resolutions, where many of these methods construct the matching and mosaic manually. In this research, georeference techniques were used to overcome the image matching task in semi automotive method. The decision about the quality of the technique can be considered i

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (3)
Scopus Crossref
Publication Date
Mon Dec 30 2024
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Reservoir permeability prediction based artificial intelligence techniques
...Show More Authors

   Predicting permeability is a cornerstone of petroleum reservoir engineering, playing a vital role in optimizing hydrocarbon recovery strategies. This paper explores the application of neural networks to predict permeability in oil reservoirs, underscoring their growing importance in addressing traditional prediction challenges. Conventional techniques often struggle with the complexities of subsurface conditions, making innovative approaches essential. Neural networks, with their ability to uncover complicated patterns within large datasets, emerge as a powerful alternative. The Quanti-Elan model was used in this study to combine several well logs for mineral volumes, porosity and water saturation estimation. This model goes be

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Mon Jun 01 2009
Journal Name
2009 Etp International Conference On Future Computer And Communication
Signal Processing Techniques for Robust Spectrum Sensing
...Show More Authors

Cognitive radios have the potential to greatly improve spectral efficiency in wireless networks. Cognitive radios are considered lower priority or secondary users of spectrum allocated to a primary user. Their fundamental requirement is to avoid interference to potential primary users in their vicinity. Spectrum sensing has been identified as a key enabling functionality to ensure that cognitive radios would not interfere with primary users, by reliably detecting primary user signals. In addition, reliable sensing creates spectrum opportunities for capacity increase of cognitive networks. One of the key challenges in spectrum sensing is the robust detection of primary signals in highly negative signal-to-noise regimes (SNR).In this paper ,

... Show More
View Publication
Scopus (4)
Crossref (2)
Scopus Clarivate Crossref