Preferred Language
Articles
/
mRfEXJIBVTCNdQwCQ61g
A N-Radon Based OFDM Trasceivers Design and Performance Simulation Over Different Channel Models
...Show More Authors

In this paper a new method is proposed to perform the N-Radon orthogonal frequency division multiplexing (OFDM), which are equivalent to 4-quadrature amplitude modulation (QAM), 16-QAM, 64-QAM, 256-QAM, ... etc. in spectral efficiency. This non conventional method is proposed in order to reduce the constellation energy and increase spectral efficiency. The proposed method gives a significant improvement in Bit Error Rate performance, and keeps bandwidth efficiency and spectrum shape as good as conventional Fast Fourier Transform based OFDM. The new structure was tested and compared with conventional OFDM for Additive White Gaussian Noise, flat, and multi-path selective fading channels. Simulation tests were generated for different channels parameters values including multi-path gains vector, multi-path delay time vector, and maximum Doppler shift. © 2009 Springer Science+Business Media, LLC.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jul 03 2005
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Purification and characterization of DNA from whole blood of children with ALL and normal children
...Show More Authors

Summary:
Background: The acute lymphocytic leukemias (All) make up about 76% of children leukemias . lymphoid leukemias occur more often than expected in patients with immunodeficiency , chromosomal abnormalities & ataxia telangiectasia . A number of chnges occur in preneoplastic & neoplastic cells as the progress towards a greater degree of malignancy . Nuclear DNA may be used as an aid in diagnosis , to predict prognosis & to determent of certain neoplasia.
Aim of the work: is to purify DNA from whole blood of predict & normal children & to characterize it by spectral studies.
Patients & Methods: Fifteen EDTA-treated blood samples of children with acute lymphoblastic leukemia (ALL) and the same number f

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 08 2023
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization and Evaluation of Some Pyranopyrazoles and Pyranopyrimidines Derivatives as Antioxidants for Lubricating Oils
...Show More Authors

6-Amino-4-(4-hydroxyphenyl)-5-cyano-3-methyl-1-phenyl-1, 4-dihydropyrano [2,3-c] pyrazole (compound 2) was prepared by condensation of 2-(4-hydroxylbenzylidine) malononitrile (compound 1) [which was prepared by Knoevenagel condensation of malononitrile with 4-hydroxy benzaldehyde ] with 3-methyl-1-phenyl-2-pyrazolin-5-one. Reactions of compound 2 with different reagents formic acid, formamide, and ammonium thiocyanate under microwave irradiation leads to the synthesis of 4-(4-hydroxyphenyl)- 3-methyl-1-phenyl-4,6-dihydro- pyrazolo [3', 4':5,6] pyrano [2,3-d] pyrimidine-5-one (compound 3), 4-(4-hydroxyphenyl)- 3-methyl-1-phenyl-4, 6-dihydro- pyrazolo [3', 4':5,6]pyrano[2,3-d]pyrimidine-5-imine (compound 4) and N-[4-(4-hydroxyphenyl)- 3-me

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 28 2023
Journal Name
Baghdad Science Journal
Synthesis and investigation of structural and optical properties of CdO: Ag nanoparticles of various concentrations
...Show More Authors

This study discussed the effects of doping with silver (Ag) on the optical and structural properties of
CdO nanoparticles at different concentrations 0, 1, 2, 3, 4, 5 wt% prepared by the precipitation method. The
materials were annealed at 550˚C for 1 h. The structural, topographical, and optical properties were
diagnosed by X-ray diffraction analysis, atomic force instrument, and visible and ultraviolet spectrometers.
The results show that the average diameter of the grains depends on the percentage of added silver to the
material, as the diameter decreased from 88.8 to 59.7 nm, and it was found that the roughness increased from
5.56 to 26.5. When studying the optical properties, it was noted that th

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Tue Jun 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Phosphorus Removal from Water and Waste Water by Chemical Precipitation Using Alum and Calcium Chloride
...Show More Authors

Phosphorus is usually the limiting nutrient for eutrophication in inland receiving waters; therefore, phosphorus concentrations must be controlled. In the present study, a series of jar test was conducted to evaluate the optimum pH, dosage and performance parameters for coagulants alum and calcium chloride. Phosphorus removal by alum was found to be highly pH dependent with an optimum pH of 5.7-6. At this pH an alum dosage of 80 mg/l removed 83 % of the total phosphorus. Better removal was achieved when the solution was buffered at pH = 6. Phosphorus removal was not affected by varying the slow mixing period; this is due to the fact that the reaction is relatively fast.
The dosage of calcium chloride and pH of solution play an importa

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 14 2022
Journal Name
Journal Of Educational And Psychological Researches
Selective Attention and Its Relation to cognitive Load and Thinking Mistakes of Baghdad University Students
...Show More Authors

The present search aims to develop a test for selective attention, cognitive load and thinking mistakes and measuring these concepts among Baghdad university students. To make a comparison between the selective attention, cognitive load, and the mistakes of thinking among students in term of gender. To identify the relationship among the selective attention, cognitive load and the mistakes of thinking of university students. To achieve these purposes, the searcher has developed a test for selective attention, cognitive load, and the mistakes of thinking. Then, these tools were applied to a sample of (200) university students were selected from (21) college. The researcher used t-test of one sample, t-test of two independent

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
Preparation and studying of some properties of polymer composites reinforced with natural and artificial fibers
...Show More Authors

This work concerns the thermal and sound insulation as well as the mechanical properties of polymer matrix composite reinforced with glass fibers. These fibers may have dangerous effect during handling, for example the glass fibers might cause some damage to the eyes, lungs and even skin. For this reason the present work, investigates the behavior of polymer composite reinforced with natural fibers (Plant fibers) as replacement to glass fibers. Unsaturated Polyester resin was used as matrix material reinforced with two types of fibers, one of them is artificial (Glass fibers) and the other type is natural (Jute, Fronds Palm and Reed Fibers) by hand lay-up technique. All fibers are untreated with any chemical solvent. The Percentage of mi

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Oct 03 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Status of Some Trace Elementsin Idiopathic and Ischemic Cardiomyopathy and Coronary Artery Disease: Echocardiographic Correlation
...Show More Authors

Background:The most principal mechanisms of cardiomyopathies are;high preload and afterload and low myocardial contractility, imbalance of trace elements may cause myocardial metabolic dysfunction and may have a role in aetiology of cardiomyopathy, particulary in IDC. Trace elements are being increasingly recognized as essential mediators of the development and progression of heart diseases.
Methods: Study design Multi case-control study and single center estimation of trace elements concentrations in a number of volunteer settings this study was conducted in the Department of Cardiology, Ibn Albitar Hospital, and in the Physiological Chemistry Department of the College of Medicine, Baghdad University, fr

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Apr 28 2022
Journal Name
Iraqi Journal Of Science
Nucleon momentum distributions and elastic electron scattering form factors for 50Cr, 52Cr and 54Cr isotopes
...Show More Authors

In the framework of correlation method so-called coherent density fluctuation model (CDFM) the nucleon momentum distributions (NMD) of the ground state for some even mass nuclei of fp-shell like 50Cr, 52Cr and 54Cr isotopes are examined. Nucleon momentum distributions are expressed in terms of the fluctuation function (|f(x)|2) which is evaluated by means of the nucleon density distributions (NDD) of the nuclei and determined from theory and experiment. The main characteristic feature of the NMD obtained by CDFM is the existence of high-momentum components, for momenta k ≥ 2 fm−1. For completeness, also elastic electron scattering form factors, F(q) are evaluated within the same framework.

View Publication Preview PDF
Publication Date
Tue Nov 30 2021
Journal Name
Iraqi Journal Of Science
Measurement and Analysis of Natural Radioactive Elements in Salty Sediments from Central and Southern Iraq
...Show More Authors

Purification of fifteen NaCl samples from natural and different area in the middle and south of Iraq are prepared  and studied the structural characteristics of samples by powder X-ray diffraction analysis at 𝛌=1.542Ã…. The present work considered the specific activities of naturally occurring radioactive materials in salt samples, which are measured and analyzed using high resolution HPGe system. Also, the radiological parameters have been considered in this work. The average specific concentration (in Bq.kg-1) of the salt samples is found 16.864.92 for 226Ra, 5.972.05 for 232Th and 9.852.8 for 40K, respectively, which are below the national levels, 40Bq.kg-1, 30Bq.k

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Tue Sep 01 2020
Journal Name
Baghdad Science Journal
Bayesian and Non - Bayesian Inference for Shape Parameter and Reliability Function of Basic Gompertz Distribution
...Show More Authors

In this paper, some estimators of the unknown shape parameter and reliability function  of Basic Gompertz distribution (BGD) have been obtained, such as MLE, UMVUE, and MINMSE, in addition to estimating Bayesian estimators under Scale invariant squared error loss function assuming informative prior represented by Gamma distribution and non-informative prior by using Jefferys prior. Using Monte Carlo simulation method, these estimators of the shape parameter and R(t), have been compared based on mean squared errors and integrated mean squared, respectively

View Publication Preview PDF
Scopus (2)
Scopus Clarivate Crossref