Preferred Language
Articles
/
joe-600
Compensation of the Nonlinear Power Amplifier by Using SCPWL Predistorter with Genetic Algorithm in OFDM technique
...Show More Authors

The High Power Amplifiers (HPAs), which are used in wireless communication, are distinctly characterized by nonlinear properties. The linearity of the HPA can be accomplished by retreating an HPA to put it in a linear region on account of power performance loss. Meanwhile the Orthogonal Frequency Division Multiplex signal is very rough. Therefore, it will be required a large undo to the linear action area that leads to a vital loss in power efficiency. Thereby, back-off is not a positive solution. A Simplicial Canonical Piecewise-Linear (SCPWL) model based digital predistorters are widely employed to compensating the nonlinear distortion that introduced by a HPA component in OFDM technology. In this paper, the genetic algorithm has been used to optimized the SCPWL coefficients by using Matlab 2015b, and then the Bit Error Rate (BER) performance has been evaluated for OFDM signal with 16-QAM and 64-QAM modulations in three cases, with nonlinear effects, without nonlinear effects (ideal case), with SCPWL and with nonlinear effects (compensated case)). The simulation results showed that the predistorter that adjusted by the genetic algorithm accomplishes huge execution change by successfully compensating the nonlinearity and reducing the input and output back-off (IBO, OBO) of the HPA.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Mar 01 2017
Journal Name
International Communications In Heat And Mass Transfer
Optimization, modeling and accurate prediction of thermal conductivity and dynamic viscosity of stabilized ethylene glycol and water mixture Al 2 O 3 nanofluids by NSGA-II using ANN
...Show More Authors

In this study, multi-objective optimization of nanofluid aluminum oxide in a mixture of water and ethylene glycol (40:60) is studied. In order to reduce viscosity and increase thermal conductivity of nanofluids, NSGA-II algorithm is used to alter the temperature and volume fraction of nanoparticles. Neural network modeling of experimental data is used to obtain the values of viscosity and thermal conductivity on temperature and volume fraction of nanoparticles. In order to evaluate the optimization objective functions, neural network optimization is connected to NSGA-II algorithm and at any time assessment of the fitness function, the neural network model is called. Finally, Pareto Front and the corresponding optimum points are provided and

... Show More
Crossref (117)
Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Baghdad College Of Dentistry
A Comparative Evaluation of Apical Seal Associated with Ultrasonic Retrograde Cavities Filled with Bioactive Material ( in Vitro Study )
...Show More Authors

Background: The aim of this study was to evaluate and compare the apical microleakage around retrograde cavities prepared with ultrasonic technique and filled with (Biodentineâ„¢) Materials and methods: 40 extracted single rooted human permanent maxillary teeth with mature apices were selected. The roots were prepared chemo-mechanically using k-files with crown-down technique and then obturated with lateral condensation gutta-percha technique. Teeth were divided into four main groups according to the cavity preparation method either manual or ultrasonic technique: Group A (n=10): A class I retrograde cavity at root end was prepared with traditional handpeice equipped and placement of Biodentine with manual condensation. Group B (n=10):

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Thu Oct 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
A study of Hepcidin levels and other Biochemical parameters in woman with Osteoporosis with Type 2 Diabetes Mellitus
...Show More Authors

Background: Diabetes mellitus (DM) could be regarded as a set of chronic metabolic disorders which have a common aspect of hyperglycemia. The resistance in the peripheral actions of insulin or impaired insulin secretion could be the reason  hepcidin which is a peptide hormone derived from liver, in systemic iron homeostasis is an essential regulator, and its lopsided production participates in the pathogenesis of iron disorders in spectrum. Osteoporosis often accompanies many diseases like ß-thalassemia, hemochromatosis, sickle liver diseases, cell disease and hemosiderosis featured by iron overload, evidences suggest that Iron overload and iron deficiency are suggested by evidences that they affect bone in a negative way, acting

... Show More
View Publication
Publication Date
Wed Sep 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
A Comparative Evaluation of Apical Seal Associated with Ultrasonic Retrograde Cavities Filled with Bioactive Material (In Vitro Study)
...Show More Authors

Background: The aim of this study was to evaluate and compare the apical microleakage around retrograde cavities prepared with ultrasonic technique and filled with (Biodentineâ„¢) Materials and methods: 40 extracted single rooted human permanent maxillary teeth with mature apices were selected. The roots were prepared chemo-mechanically using k-files with crown-down technique and then obturated with lateral condensation gutta-percha technique. Teeth were divided into four main groups according to the cavity preparation method either manual or ultrasonic technique: Group A (n=10): A class I retrograde cavity at root end was prepared with traditional handpeice equipped and placement of Biodentine with manual condensation. Group B (n=10):

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Dec 01 2017
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Humoral immune factor changes in group of patients with Non-muscle invasive bladder cancer treated with intravesical therapy.
...Show More Authors

Publication Date
Fri Nov 21 2025
Journal Name
Plos Global Public Health
Association of socioeconomic and demographic determinants with clinical outcomes in Iraqi patients with diabetes: A cross-sectional study
...Show More Authors

Social determinants of health (SDH) profoundly influence diabetes outcomes; nevertheless, their impact on the Iraqi diabetic population remains under researched. The objectives of this study were To investigate the relationship between particular social determinants of health (SDH) variables namely food and housing insecurity, social support, income, and education and clinical outcomes, including HbA1c levels, medication adherence, and patient satisfaction among Iraqi diabetic patients. A cross-sectional study involving 212 diabetic patients in Iraq was conducted. Participants attending a healthcare facility in Iraq filled out validated questionnaires regarding social determinants of health, medication adherence, and satisfaction. HbA1c rea

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jul 01 2013
Journal Name
International Journal Of Computer Applications
Mixed Convection in a Square Cavity Filled with Porous Medium with Heated Bottom Wall
...Show More Authors

Two-dimensional unsteady mixed convection in a porous cavity with heated bottom wall is numerically studied in the present paper. The forced flow conditions are imposed by providing a hydrostatic pressure head at the inlet port that is located at the bottom of one of the vertical side walls and an open vent at the top of the other vertical side wall. The Darcy model is adopted to model the fluid flow in the porous medium and the combination effects of hydrostatic pressure head and the heat flux quantity parameters are carefully investigated. These governing parameters are varied over wide ranges and their effect on the heat transfer characteristics is studied in detail. It is found that the time required to reach a desired temperature at th

... Show More
Publication Date
Wed Nov 07 2018
Journal Name
Asian Journal Of Pharmaceutical And Clinical Research
HYDROGEN PEROXIDE LEVELS CORRELATE WITH SUPEROXIDE DISMUTASE IN IRAQI WOMEN WITH PREGNANCY-INDUCED HYPERTENSION
...Show More Authors

Objective: Pregnancy-induced hypertension (PIH) is a major pregnancy complication that leads to maternal mortality. Here, we have scrutinized the correlation between serum levels of hydrogen peroxide (H2O2) and superoxide dismutase (SOD) in PIH.Methods: Serum samples were collected from 80 Iraqi women (40 women with PIH as patients group, 20 normotensive pregnant women as a positive control, and 20 normotensive non-pregnant women as a negative control) all groups were diagnosed clinically.Results: Serum of H2O2 and SOD levels was measured for all studied groups. Results showed that there were no significant variances in age and gestational age distribution between all studied groups. Furthermore, result showed that the serum level o

... Show More
View Publication
Scopus Crossref
Publication Date
Thu Jan 01 2009
Journal Name
Arab Journal Of Gasteroenterology
Serum HCV-RNA levels in patients with chronic hepatitis C: correlation with histological features.
...Show More Authors

Publication Date
Fri May 01 2009
Journal Name
Atti Della “fondazione Giorgio Ronchi”
Study of synthesis of nanocrystalline CdS thin film in PVA matrix by chemical bath deposition
...Show More Authors

SUMMARY. – Nanocrystalline thin fi lms of CdS are deposited on glass substrate by chemical bath deposited technique using polyvinyl alcohol (PVA) matrix solution. Crystallite size of the nanocrystalline films are determining from broading of X-ray diffraction lines and are found to vary from 0.33-0.52 nm, an increase of molarity the grain size decreases which turns increases the band gap. The band gap of nanocrystalline material is determined from the UV spectrograph. The absorption edge and absorption coefficient increases when the molarity increases and shifted towards the lower wavelength.

Preview PDF