Preferred Language
Articles
/
URfCNY8BVTCNdQwCKWI1
A combined compact genetic algorithm and local search method for optimizing the ARMA(1,1) model of a likelihood estimator
...Show More Authors

In this paper, a compact genetic algorithm (CGA) is enhanced by integrating its selection strategy with a steepest descent algorithm (SDA) as a local search method to give I-CGA-SDA. This system is an attempt to avoid the large CPU time and computational complexity of the standard genetic algorithm. Here, CGA dramatically reduces the number of bits required to store the population and has a faster convergence. Consequently, this integrated system is used to optimize the maximum likelihood function lnL(φ1, θ1) of the mixed model. Simulation results based on MSE were compared with those obtained from the SDA and showed that the hybrid genetic algorithm (HGA) and I-CGA-SDA can give a good estimator of (φ1, θ1) for the ARMA(1,1) model. Another comparison has been conducted to show that the I-CGA-SDA has fewer function evaluations, minimum search space percentage, faster convergence speed and has a higher optimal precision than that of the HGA.

Scopus Clarivate Crossref
View Publication
Publication Date
Sun Jun 30 2002
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Determination of Surface Diffusion Coefficient for Adsorption Process
...Show More Authors

View Publication Preview PDF
Publication Date
Thu Oct 01 2015
Journal Name
Al–bahith Al–a'alami
Coverage of Iraqi Sports Newspapers for Major Events
...Show More Authors

                   The Iraqi sports journalism has paid great attention to sports events through press coverage of all its forms and arts, especially the coverage of the World Cup of football which is one of the most watched events in the world. Thousands of journals are preparing for the immediate coverage of such event which is a daunting task in itself. Newspapers have devoted a wider space to this great event in its pages as well as the weakly sports newspapers work on issuing a daily special issue. The importance of this research sheds light on the coverage of major events such as World Cup in Iraqi newspapers. The topic is new

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Existence of Positive Solution for Boundary Value Problems
...Show More Authors

  This paper studies the existence of  positive solutions for the following boundary value problem :-
 
 y(b) 0 α y(a) - β y(a) 0     bta             f(y) g(t) λy    
 
 
The solution procedure follows using the Fixed point theorem and obtains that this problem has at least one positive solution .Also,it determines (  ) Eigenvalue which would be needed to find the positive solution .

View Publication Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Iraqi Journal Of Applied Physics
Fabrication of PAN:Cellulose Membrane for Oil/Water Separation
...Show More Authors

In this study, we fabricated nanofiltration membranes using the electrospinning technique, employing pure PAN and a mixed matrix of PAN/HPMC. The PAN nanofibrous membranes with a concentration of 13wt% were prepared and blended with different concentrations of HPMC in the solvent N, N-Dimethylformamide (DMF). We conducted a comprehensive analysis of these membranes' surface morphology, chemical composition, wettability, and porosity and compared the results. The findings indicated that the inclusion of HPMC in the PAN membranes led to a reduction in surface porosity and fiber size. The contact angle decreased, indicating increased surface hydrophilicity, which can enhance flux and reduce fouling tendencies. Subsequently, we evaluated the e

... Show More
Scopus
Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Synthesis, Characterization of Derivatives Tetrazoles for Trimethoprim Drug
...Show More Authors

The present work involved synthesis of serval new substituted tetrazole via Schiff bases for trimethoprim drug by two steps. The first step involved direct reaction of different ketones and aldehydes with trimethoprim producing the corresponding Schiff bases (1-10), whereas the second step, involved preparation new tetrazoles derivatives (11-20) through reaction of the ready Schiff bases (in the first step) with sodium azidein in dioxin. The prepared compounds were characterized by UV, FT-IR, and some of them by 13C-NMR, 1H-NMR spectroscopy and physical properties.

View Publication Preview PDF
Crossref
Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Study of optical properties for Ge - GaAs Heterojunction
...Show More Authors

View Publication Preview PDF
Crossref
Publication Date
Thu Dec 31 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Prediction of Shear Wave velocity for carbonate rocks
...Show More Authors

In many oil fields only the BHC logs (borehole compensated sonic tool) are available to provide interval transit time (Δtp), the reciprocal of compressional wave velocity VP.

   To calculate the rock elastic or inelastic properties, to detect gas-bearing formations, the shear wave velocity VS is needed. Also VS is useful in fluid identification and matrix mineral identification.

   Because of the lack of wells with shear wave velocity data, so many empirical models have been developed to predict the shear wave velocity from compressional wave velocity. Some are mathematical models others used the multiple regression method and neural network technique.

   In this study a number of em

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2007
Journal Name
Journal Of Al-nahrain University
Applications Of Strong-Lensing For Some Gravitational Lenses
...Show More Authors

In our work present, the application of strong-Lensing observations for some gravitational lenses have been adopted to study the geometry of the universe and to explain the physics and the size of the quasars. The first procedure was to study the geometrical of the Lensing system to determine the relation between the redshift of the gravitational observations with its distances. The second procedure was to compare between the angular diameter distances "DA" calculated from the Euclidean case with that from the Freedman models, then evaluating the diameter of the system lens. The results concluded that the phenomena are restricted to the ratio of distance between lens and source with the diameter of the lens noticing.

Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Investigation of Numerical Simulation for Adaptive Optics System
...Show More Authors

In this study, the performance of the adaptive optics (AO) system was analyzed through a numerical computer simulation implemented in MATLAB. Making a phase screen involved turning computer-generated random numbers into two-dimensional arrays of phase values on a sample point grid with matching statistics. Von Karman turbulence was created depending on the power spectral density. Several simulated point spread functions (PSFs) and modulation transfer functions (MTFs) for different values of the Fried coherent diameter (ro) were used to show how rough the atmosphere was. To evaluate the effectiveness of the optical system (telescope), the Strehl ratio (S) was computed. The compensation procedure for an AO syst

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Antimagic Labeling for Some Families of Graphs
...Show More Authors

Antimagic labeling of a graph  with  vertices and  edges is assigned the labels for its edges by some integers from the set , such that no two edges received the same label, and the weights of vertices of a graph  are pairwise distinct. Where the vertex-weights of a vertex  under this labeling is the sum of labels of all edges incident to this vertex, in this paper, we deal with the problem of finding vertex antimagic edge labeling for some special families of graphs called strong face graphs. We prove that vertex antimagic, edge labeling for strong face ladder graph , strong face wheel graph ,  strong face fan graph , strong face prism graph  and finally strong face friendship graph .

View Publication Preview PDF
Crossref