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
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Darwinian Philosophy as Optimization Method for Design High Reflection Mirror Include New Merit Function
...Show More Authors

In this paper we proposes the philosophy of the Darwinian selection as synthesis method called Genetic algorithm ( GA ), and include new merit function with simple form then its uses in other works for designing one of the kinds of multilayer optical filters called high reflection mirror. Here we intend to investigate solutions for many practical problems. This work appears designed high reflection mirror that have good performance with reduction the number of layers, which can enable one to controlling the errors effect of the thickness layers on the final product, where in this work we can yield such a solution in a very shorter time by controlling the length of the chromosome and optimal genetic operators . Res

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 30 2024
Journal Name
Tikrit Journal For Agricultural Sciences
First record to the spider Scytodes univittata (Araneae:Scytodidae)in Baghdad, Iraq
...Show More Authors

This study is  the first and  new record  to the spider Scytodes univittata Simon, 1882  (Araneae:Scytodidae)in Baghdad /Iraq , the spiders Scytodes univittata  were collect from province Baghdad in Iraq , genus Scytodes belong to the  family Scytodidae  it is one of the most family are wide  distribution around the world have 6 eyes and are slow moving  , the genus Scytodes are known from the names spitting spiders ,.Female Scytodes univittata   can be characteristic by :large round cephalothorax length:4.45 mm , abdomen length 3.50, total body length  7.95 mm and V-shaped of  fovea, scutela triangle and large  with long  thin legs femur I have two row of spines then  spineless are in IV femur , coloration  is yello

... Show More
View Publication
Scopus Crossref
Publication Date
Wed Dec 18 2019
Journal Name
Bulletin Of Materials Science
Investigation of optical properties and glass transition temperature of nano-epoxy matrix
...Show More Authors

View Publication
Scopus (2)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sun Sep 03 2017
Journal Name
Baghdad Science Journal
Keys for Isolation suborders and Families and genera and species of Book and Bark lice in Baghdad and Babylon [Order PSOCOPTERA]
...Show More Authors

A taxonomic keys was established of book and bark lice Order Psocoptera to isolated insects in Iraq from different localities of Baghdad and Babylon provinces. Thirteen species belong to eight genera and five families have been studied and described in details, these species were recorded for the first time in Iraq. These species are: Belaphopsocus badonneli New, 1971; Belaphotroctes oculeris Bodonnel, 1973; Embodopsocosis newi Bodonnel, 1973; Epipsocus stigamaticus Mockeord, 1991; Lepinotus huoni Schmidt and New, 2008; Liposcelies decolor Peramane 1925 Liposcelies paeta Pearman 1942 Liposclies bostrychphila Badonnel 1931; Liposclies brunnea Mostchulsky 1852; Liposclies entoophila Enderlein 1907; Neopsocopsis minuscule Li 2002 ;

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
The effect of short range correlation on the inelastic C2 and C4 form factors of 18O nucleus
...Show More Authors

The effect of short range correlations on the inelastic Coulomb form factors for excited +2 states (1.982, 3.919, 5.250 and 8.210MeV) and +4 states (3.553, 7.114, 8.960 and 10.310 MeV) in O18 is analyzed. This effect (which depends on the correlation parameterβ) is inserted into the ground state charge density distribution through the Jastrow type correlation function. The single particle harmonic oscillator wave function is used with an oscillator size parameter .b The parameters β and b are adjusted for each excited state separately so as to reproduce the experimental root mean square charge radius of .18O The nucleusO18 is considered as an inert core of C12 with two protons and four neutrons distributed over 212521211sdp−− activ

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
An Approximated Solutions for nth Order Linear Delay Integro-Differential Equations of Convolution Type Using B-Spline Functions and Weddle Method
...Show More Authors

The paper is devoted to solve nth order linear delay integro-differential equations of convolution type (DIDE's-CT) using collocation method with the aid of B-spline functions. A new algorithm with the aid of Matlab language is derived to treat numerically three types (retarded, neutral and mixed) of nth order linear DIDE's-CT using B-spline functions and Weddle rule for calculating the required integrals for these equations. Comparison between approximated and exact results has been given in test examples with suitable graphing for every example for solving three types of linear DIDE's-CT of different orders for conciliated the accuracy of the results of the proposed method.

View Publication Preview PDF
Crossref
Publication Date
Thu Oct 01 2015
Journal Name
International Journal Of Current Engineering And Technology
Synthesis of Gold Nanoparticle in the form of Paper Willow by Hot Chemical Reduction Method
...Show More Authors

Abstract: Colloidal gold nanoparticles (ringworm Palm or in the form of paper willow) have been prepared from HAuCl4 containing aqueous solution by hot chemical reduction method. The colloidal gold nanoparticles were characterized by SEM, EDX, and UV-VIS absorption spectroscopy. It was found that the variation of reduction time from boiling point affects the size of the nanoparticles and also in chemical reduction approach the size of nanoparticles can be controlled by varying the amount of variation the volume of reductant material with respect to the volume of HAuCL4.

Preview PDF
Publication Date
Sun Jul 01 1990
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FIRST RECORD OF FIVE NEMATODES FROM IRAQI TURTLES
...Show More Authors

During a survey on the helminthic parasites of three species of turtles in the north part of Iraq, five species of nematodes were recorded for the first time in Iraq. They were all found in the intestine. These are, Camallanus microcephalus (Dujardin, 1845) recorvered from the turtle Clemmys caspica; Spironoura japonensis (Yamaguti, 1935) from Triopyx eup¬hraticus and Angusticaecum holopterum (Rudolphi, 1819), and Tachygonetria nicollei (Seurat, 1918) from the turtle Testudo graeca. All of the localities and hosts are newly recorded in Iraq.

View Publication Preview PDF
Publication Date
Mon Dec 24 2018
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FIRST RECORDS OF PHOLCIDAE (ARACHNIDA, ARANEAE) FROM IRAQ
...Show More Authors

    The family Pholcidae represented by the species Artema doriae )Thorell, 1881) is recorded in Iraq for the first time.So far, 23 families of spiders have been recorded in Iraq.

     In this paper, we add a new family and a description of a species belonging to this family in the checklist of Iraqi spider fauna.

View Publication Preview PDF
Scopus (12)
Crossref (5)
Scopus Crossref
Publication Date
Thu Dec 21 2023
Journal Name
Mathematical Modelling Of Engineering Problems
Recovering Time-Dependent Coefficients in a Two-Dimensional Parabolic Equation Using Nonlocal Overspecified Conditions via ADE Finite Difference Schemes
...Show More Authors

View Publication Preview PDF
Scopus (1)
Scopus Crossref