Preferred Language
Articles
/
bsj-4329
Matrix Form of Deriving High Order Schemes for the First Derivative
...Show More Authors

For many problems in Physics and Computational Fluid Dynamics (CFD), providing an accurate approximation of derivatives is a challenging task. This paper presents a class of high order numerical schemes for approximating the first derivative. These approximations are derived based on solving a special system of equations with some unknown coefficients. The construction method provides numerous types of schemes with different orders of accuracy. The accuracy of each scheme is analyzed by using Fourier analysis, which illustrates the dispersion and dissipation of the scheme. The polynomial technique is used to verify the order of accuracy of the proposed schemes by obtaining the error terms. Dispersion and dissipation errors are calculated and compared to show the features of high order schemes. Furthermore, there is a plan to study the stability and accuracy properties of the present schemes and apply them to standard systems of time dependent partial differential equations in CFD.   

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Oct 01 2020
Journal Name
Alexandria Engineering Journal
The operational matrix of Legendre polynomials for solving nonlinear thin film flow problems
...Show More Authors

Scopus (11)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Derivation of Crystal Orientation Matrix for Triclinic System on Two-circle Diffractometer
...Show More Authors

 The limited availability of the two-circle diffractometer to collect intensity measurements down to the monoclinic system has been extended in a novel procedure to collect intensities for the triclinic system. The procedure involves the derivation of matrix elements from graphical representation of the reciprocal lattice. Offset of  the origins of  the upper layers from that of the zero-layer - characteristic of triclinic system - is determined and the  3 x 3  matrix elements are evaluated accordingly. Details of  crystal alignment by X-rays for the triclinic system utilizing the intensities of  equivalent reflections is described

View Publication Preview PDF
Publication Date
Sun Dec 03 2017
Journal Name
Al-khwarizmi Engineering Journal
Performance of Turbo-Codes with Some Proposed Interleaver Schemes
...Show More Authors

This paper describes a number of new interleaving strategies based on the golden section. The new interleavers are called golden relative prime interleavers, golden interleavers, and dithered golden interleavers. The latter two approaches involve sorting a real-valued vector derived from the golden section. Random and so-called “spread” interleavers are also considered. Turbo-code performance results are presented and compared for the various interleaving strategies. Of the interleavers considered, the dithered golden interleaver typically provides the best performance, especially for low code rates and large block sizes. The golden relative prime interleaver is shown to work surprisingly well for high puncture rates. These interleav

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 07 2024
Journal Name
Semiconductor Science And Technology
A facile method of deriving solar selective nickel-cobalt oxide thin films via spraying process
...Show More Authors
Abstract<p>The present study focuses on synthesizing solar selective absorber thin films, combining nanostructured, binary transition metal spinel features and a composite oxide of Co and Ni. Single-layered designs of crystalline spinel-type oxides using a facile, easy and relatively cost-effective wet chemical spray pyrolysis method were prepared with a crystalline structure of M<sub>x</sub>Co<sub>3−x</sub>O<sub>4</sub>. The role of the annealing temperature on the solar selective performance of nickel-cobalt oxide thin films (∼725 ± 20 nm thick) was investigated. XRD analysis confirmed the formation of high crystalline quality thin films with a crystallite si</p> ... Show More
View Publication
Scopus Clarivate Crossref
Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Studying the Classification of Texture Images by K-Means of Co-Occurrence Matrix and Confusion Matrix
...Show More Authors

In this research, a group of gray texture images of the Brodatz database was studied by building the features database of the images using the gray level co-occurrence matrix (GLCM), where the distance between the pixels was one unit and for four angles (0, 45, 90, 135). The k-means classifier was used to classify the images into a group of classes, starting from two to eight classes, and for all angles used in the co-occurrence matrix. The distribution of the images on the classes was compared by comparing every two methods (projection of one class onto another where the distribution of images was uneven, with one category being the dominant one. The classification results were studied for all cases using the confusion matrix between ev

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Studying the Classification of Texture Images by K-Means of Co-Occurrence Matrix and Confusion Matrix
...Show More Authors

In this research, a group of gray texture images of the Brodatz database was studied by building the features database of the images using the gray level co-occurrence matrix (GLCM), where the distance between the pixels was one unit and for four angles (0, 45, 90, 135). The k-means classifier was used to classify the images into a group of classes, starting from two to eight classes, and for all angles used in the co-occurrence matrix. The distribution of the images on the classes was compared by comparing every two methods (projection of one class onto another where the distribution of images was uneven, with one category being the dominant one. The classification results were studied for all cases using the confusion matrix between every

... Show More
Preview PDF
Crossref (3)
Crossref
Publication Date
Sun Mar 12 2017
Journal Name
Al-academy
Alienation form for ornament’s clouds in Quran
...Show More Authors

This research attend about Alienation form for ornament’s clouds in Quran, which includes four parts, the first part talks about the research problem, the researcher identified by following question :( what’s the Alienation form for ornament’s clouds in Quran?). And then the research importance. The research goal talks about Alienation form for ornament’s clouds in Quran. And also research borders, likes means objectives borders, places borders, As well as Terms Definitions, in second part talks about Theoretical framework and previous studies, includes two parts, the first one study Alienation form, meaning and understandable, the second one talks about Alienation form in Islamic arts, As well as the researcher find only one stu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
Positive Definiteness of Symmetric Rank 1 (H-Version) Update for Unconstrained Optimization
...Show More Authors

Several attempts have been made to modify the quasi-Newton condition in order to obtain rapid convergence with complete properties (symmetric and positive definite) of the inverse of  Hessian matrix (second derivative of the objective function). There are many unconstrained optimization methods that do not generate positive definiteness of the inverse of Hessian matrix. One of those methods is the symmetric rank 1( H-version) update (SR1 update), where this update satisfies the quasi-Newton condition and the symmetric property of inverse of Hessian matrix, but does not preserve the positive definite property of the inverse of Hessian matrix where the initial inverse of Hessian matrix is positive definiteness. The positive definite prope

... Show More
View Publication Preview PDF
Scopus (9)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Mon Apr 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Spectrophotometric Method for the Estimation of Ceftriaxone in Pure Form and Pharmaceuticals
...Show More Authors

Ceftriaxone sodium were one of the widely antibacterial drugs used. Azo dye derivatization of diazonium salt that formed via the reaction between ceftriaxone with hydrochloric acid and sodium nitrite was developed for the on-research drug analysis then coupling with each one 2,5-dimethylphenol (2,5-DMP) and 4-tertbutylphenol (4-TBP) respectively in the alkaline media. The developed diazonium coupling methods include an optimization study. The results show a limit of detection and limit of quantification 0.482, 0.284 µg/mL, and 1.607, 0.945 µg/mL using 2,5-DMP and 4-TBP reagents respectively. Moreover, the recovery % obtained was 100.89%, and 103.37% at linear concentration range 3.0 – 50, and 10 – 30 µg/mL, with mo

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
The Electro-Excitation Form Factors for Low-Lying States of 7Li Nucleus
...Show More Authors

The transverse electron scattering form factors have been studied for low –lying excited states of 7Li nucleus. These states are specified by J? T= (0.478MeV), (4.63MeV) and (6.68MeV). The transitions to these states are taking place by both isoscalar and isovector components. These form factors have been analyzed in the framework of the multi-nucleon configuration mixing of harmonic oscillator shell model with size parameter brms=1.74fm. The universal two-body of Cohen-Kurath is used to generate the 1p-shell wave functions. The core polarization effects are included in the calculations through effective g-factors and resolved many discrepancies with experiments. A higher configuration effect outside the 1p-shell model space, such

... Show More
View Publication Preview PDF
Crossref