Preferred Language
Articles
/
WxfGNY8BVTCNdQwCNmLJ
Hybrid canonical genetic algorithm and steepest descent algorithm for optimizing likelihood estimators of ARMA (1, 1) model
...Show More Authors

This paper presents a hybrid genetic algorithm (hGA) for optimizing the maximum likelihood function ln(L(phi(1),theta(1)))of the mixed model ARMA(1,1). The presented hybrid genetic algorithm (hGA) couples two processes: the canonical genetic algorithm (cGA) composed of three main steps: selection, local recombination and mutation, with the local search algorithm represent by steepest descent algorithm (sDA) which is defined by three basic parameters: frequency, probability, and number of local search iterations. The experimental design is based on simulating the cGA, hGA, and sDA algorithms with different values of model parameters, and sample size(n). The study contains comparison among these algorithms depending on MSE value. One can conclude that (hGA) can give good estimators (phi(1),theta(1)) of ARMA(1,1)parameters and more reliable than estimators obtained by cGA and SDA algorithm

Scopus Crossref
View Publication
Publication Date
Wed Apr 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of Fuzzy σ-Ring  and Some Related Concepts
...Show More Authors

This paper introduces the concept of fuzzy σ-ring as a generalization of fuzzy σ-algebra and basic properties; examples of this concept have been given.  As the first result, it has been proved that every  σ-algebra over a fuzzy set x*  is a  fuzzy σ-ring-over a fuzzy set x*  and construct their converse by example. Furthermore, the fuzzy ring  concept has been studied to generalize fuzzy algebra and its relation. Investigating  that the concept of fuzzy  σ-Ring is a stronger form of a fuzzy ring  that is every fuzzy σ-Ring over a fuzzy set x* is a fuzzy ring over a fuzzy set x* and construct their converse by example. In addition, the idea of the smallest, as an important property in the study of real analysis, is studied

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
the periodic coincidence points of continuius maps and lindemann's
...Show More Authors

this paper give a proof of known conditions for the existence of peridic conincidence points of continuius maps using lindemann theotem on transcendental numbers

View Publication Preview PDF
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The Development of the Suez Canal and Projects Competitors
...Show More Authors

The area around the Suez Canal has been chosen particularly  Sinai  to implement the new Suez Canal project parallel to the original 72-km-long channel due to the importance of the commercial site of the Arab Republic of Egypt, competing with shipping lanes, to accommodate the increasing maritime traffic  passing through the Suez canal, and to provide special services for trade world and reduce the economic cost of marine trip. The establishment of six tunnels for automobile and railway transport to Sinai The cost of the establishment of this new channel  and the establishment of the tunnels about (2.8) billion, of which 4 billion cost of the new channel. Project implementation period is one year. The new proj

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
Transitional justice: a study of the concept and mechanisms
...Show More Authors

The concept of transitional justice is newly emerging, as it was mainly associated with addressing issues of serious breaches and abuses of human rights during conflicts and situations resulting from violence and the use of force in societies that are in the process of democratization, as transitional justice aims primarily to restore civil peace and rebuild institutions The state needs multidimensional justice: a judicial system that achieves the rule of law, corrective restoration of the wounds of the past, and a distributive characteristic of the redistribution of wealth.

View Publication Preview PDF
Crossref
Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Fabrication and Characterization of Silicon Nanowires Heterojunction Solar Cell
...Show More Authors

Silicon nanowire arrays (SiNWs) are created utilizing the metal-assisted chemical etching method with an Ag metal as a catalyst and different etching time of 15, 30, and 60 minutes using n-Si (100). Physical properties such as structural, surface morphology, and optical properties of the prepared SiNWs are studied. The diameter of prepared SiNWs ranged from 20 to 280 nm, and the reflectance in the visible part of the wavelength spectrum was less than 1% for all prepared samples. The obtained energy gap of prepared SiNWs was around 2 eV, which is higher than the energy gap of bulk silicon. X-ray diffraction (XRD) has diffraction peaks at 68.70o for all prepared samples. The heterojunction solar cell was fabricated based on the

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Partial Purification and Characterization of Catalase from Banana Peels
...Show More Authors

Catalase (EC 1.11.1.6) is a well known enzyme which exists in almost all living creatures exposing to oxygen (such as plants, bacteria, and animals). It is a very necessary enzyme to protect the cell from oxidative detriment by reactive oxygen species (ROS). The aim of this study is the partial purification and characterization of Catalase enzyme from Banana peels. In this study, fresh banana peels are treated with 70 % ethanol ,further separated with chloroform ,water and ethyl acetate respectively .The supernatant of the enzymatic sample which is treated with chloroform is loaded into gel filtration column with Sephadex G-100 (1.0 x 90 cm) equilibrated with pH7 buffer media (phosphate buffer 0.1 M). Kinetic studies of the purified en

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Buckling Analysis of Stiffened and Unstiffened Laminated Composite Plates
...Show More Authors

The present study focused mainly on the analysis of stiffened and unstiffened composite laminated plates subjected to buckling load. Analytical, numerical and experimental analysis for different cases has been considered. The experimental investigation is to manufacture the laminates and to find mechanical properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus. The compressive test was carried to find the critical buckling load of plate. The design parameters of the laminates such as aspect ratio, thickness ratio, boundary conditions and number of stiffeners were investigated using high order shear deformation theory (HOST) and Finite element coded by ANSYS .The main conclusion was the buckling load c

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Five, Sevene Heterocyclic Membered Rings
...Show More Authors

New compounds containing heterocyclic units have been synthesized. These compounds include 2-amino 5- phenyl-1,3,4-thiadiazole (1) as starting material to prepare the Schiff bases 2N[3-nitrobenzylidene -2 hydroxy benzylidene and 4-N,N-dimethyl aminobenzylidene] -5-phenyl-1,3,4-thiadiazole (2abc) , 2N[3-nitrophenyl, 2-hydroxyphenyl or 4-N,N-dimethylaminophenyl] 3-]2-amino-5-phenyl-1,3,4-thiadiazole]-2,3-dihydro-[1,3]oxazepine-benzo-4,7-dione] (3abc), 2N[3-nitrophenyl,2-hydroxyphenyl,4-N,N-dimethylaminophenyl]-3-[2-amino-5-phenyl-1,3,4-thiadiazole-2-yl]-2,3-dihydro-[1,3]oxazepine-4,7-dione[(4abc), 2-N-[3-nitrophenyl, 2-hydroxyphenyl or 4-N,N-dimethylaminophenyl]-3-[2-amino-5-phenyl-1,3,4-thiadiazole-2yl]-1,2,3-trihydro-benzo-[1,2-e][1,3] diaz

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Oct 03 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Outcome of laparoscopic cholecystectomy in acute and chronic cholecystitis.
...Show More Authors

Background: laparoscopic cholecystectomy is standard treatment in gallbladder disease. Acute cholecystitis has been relative contraindication of laparoscopic cholecystectomy. With the
accumulation of experience in laparoscopic surgery, laparoscopic cholecystectomy is being gradually applied for the treatment of acute cholecystitis
Objective: to evaluate and compare the outcome of laparoscopic cholecystectomy in acute and chronic cholecystitis in terms of complications, conversion rates, reason of conversion, need for special modifications of the operative technique, and hospital stay.
Methods: A prospective study done Between April 2007 and January 2010, in the department of general surgery, medical city teac

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 30 2012
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Production and Evaluation of Biodiesel from Sheep Fats Waste
...Show More Authors

Animal fats are a good, promising and ethical alternative source for biodiesel production, but they need more complex treatments than vegetable oils. Iraqi butchery plants waste fats (sheep fat) which are suggested as feedstock to produce biodiesel. This type of fat contains a large quantity of free fatty acids (FFAs) (acid number 49.13 mg KOH/g of fat). The direct transesterification of such fats produce high amount of soap instead of desired biodiesel, so a pre-treatment step (to reduce FFAs) is necessary before transesterification. This step was done by esterification of the free fatty acids in the fat by adding ethanol and using 1% acid catalyst (H2SO4) for 30 minutes. The results showed that the acid number of sheep fat after pre-tr

... Show More
View Publication Preview PDF