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New Adaptive Data Transmission Scheme Over HF Radio
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Acceptable Bit Error rate can be maintained by adapting some of the design parameters such as modulation, symbol rate, constellation size, and transmit power according to the channel state.

An estimate of HF propagation effects can be used to design an adaptive data transmission system over HF link. The proposed system combines the well known Automatic Link Establishment (ALE) together with variable rate transmission system. The standard ALE is modified to suite the required goal of selecting the best carrier frequency (channel) for a given transmission. This is based on measuring SINAD (Signal plus Noise plus Distortion to Noise plus Distortion), RSL (Received Signal Level), multipath phase distortion and BER (Bit Error Rate) for each channel in the frequency list. Channel condition evaluation is done by two arrangements. In the first an FFT analysis is used where a pilot signal is transmitted over the channel, while the data itself is used in the second arrangement. Passive channel assessment is used to avoid bad channels hence limiting the frequency pool size to be used in the point to point communication and the time required for  scanning and linking. An exchange of channel information between the transmitting and receiving stations is considered to select the modulation scheme for transmission. Mainly MPSK and MFSK are considered with different levels giving different data rate according to the channel condition. The results of the computer simulation have shown that when transmitting at a fixed channel symbol rate of 1200 symbol/sec, the information rate ranges from 2400 bps using 4FSK up to 3600 bps using 8PSK for SNR ranges from 11dB up to 26dB.

 

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Publication Date
Wed Mar 01 2023
Journal Name
Baghdad Science Journal
New Structures of Continuous Functions
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         Continuous functions are novel concepts in topology. Many topologists contributed to the theory of continuous functions in topology. The present authors continued the study on continuous functions by utilizing the concept of gpα-closed sets in topology and introduced the concepts of weakly, subweakly and almost continuous functions. Further, the properties of these functions are established.

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Publication Date
Mon Sep 01 2014
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Customer Satisfaction... New Accounting Revolution
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During the ongoing economic revolutions of the economic There is a new economic revolution is emboded by upseting the balances of prevailing classic ideas and refusing axioms considered postulates which were not touched including, for example, the theory of ( supply and demand) espoused by (Adam Smith and Marshall and others ) that assumes the existence of a strong relationship between the supply of goods and services and the demand for them, in the light of successive economic developments, considerable technological progress and the information revolution of the complex telecommunication network led to a serious shift of this theory and the emergence of a new theory called (market economies) turned the traditional scales of production,

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Publication Date
Wed Jan 30 2013
Journal Name
Al-kindy College Medical Journal
Over expression of Her- 2 neu in ovarian surface epithelial carcinoma in a sample of Iraqi patient at Al-kindy Teaching Hospital.
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Background: Although expression of the HER-
2/neuoncogene may be of some prognostic importance
in advanced ovarian cancer, its role in early-stage
disease has not been established. The current study
examined the prevalence and significance of HER-
2/neu expression in different grades of different types
of surface epithelial ovarian carcinoma.
Methods: Thirty eight female patients with surface
epithelial ovarian cancer were included in this study.
The blocks of corresponding formalin fixed, paraffinembedded
ovarian biopsies were retrieved from the
archives and hematoxylin-eosin slides of each ovarian
biopsy were reviewed and marked their grades of
differentiation , then a new sections from each sampl

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Publication Date
Thu May 05 2022
Journal Name
Karbala International Journal Of Modern Science
Heterogeneous catalytic degradation of dye by Fenton-like oxidation over a continuous system based on Box–Behnken design and traditional batch experiments
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In this study, iron was coupled with copper to form a bimetallic compound through a biosynthetic method, which was then used as a catalyst in the Fenton-like processes for removing direct Blue 15 dye (DB15) from aqueous solution. Characterization techniques were applied on the resultant nanoparticles such as SEM, BET, EDAX, FT-IR, XRD, and zeta potential. Specifically, the rounded and shaped as spherical nanoparticles were found for green synthesized iron/copper nanoparticles (G-Fe/Cu NPs) with the size ranging from 32-59 nm, and the surface area was 4.452 m2/g. The effect of different experimental factors was studied in both batch and continuous experiments. These factors were H2O2 concentration, G-Fe/CuNPs amount, pH, initial DB15

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Scopus (13)
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Publication Date
Sat Nov 13 2021
Journal Name
International Journal Of Pharmacy Practice
A comprehensive review of drivers influencing flu vaccine acceptance in the Middle East over the last six years: using Health Belief Model
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Abstract<sec> <title>Objectives

The objectives of this study were to review the literature covering the perceptions about influenza vaccines in the Middle East and to determine factors influencing the acceptance of vaccination using Health Belief Model (HBM).

Methods

A comprehensive literature search was performed utilizing PubMed and Google Scholar databases. Three keywords were used: Influenza vaccine, perceptions and Middle East. Empirical studies that dealt with people/healthcare worker (HCW) perceptio

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Scopus (11)
Crossref (14)
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Publication Date
Sat Nov 13 2021
Journal Name
International Journal Of Pharmacy Practice
A comprehensive review of drivers influencing flu vaccine acceptance in the Middle East over the last six years: using Health Belief Model
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Abstract<sec> <title>Objectives

The objectives of this study were to review the literature covering the perceptions about influenza vaccines in the Middle East and to determine factors influencing the acceptance of vaccination using Health Belief Model (HBM).

Methods

A comprehensive literature search was performed utilizing PubMed and Google Scholar databases. Three keywords were used: Influenza vaccine, perceptions and Middle East. Empirical studies that dealt with people/healthcare worker (HCW) perceptio

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Scopus (11)
Crossref (14)
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Publication Date
Thu Feb 01 2024
Journal Name
Journal Of Thermal Analysis And Calorimetry
Heat transfer and fluid flow characteristics over a backward-facing step (BFS) containing square-rectangular ribs integrated as forward-facing steps (FFS)
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Publication Date
Sat Oct 03 2026
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
Modified LASS Method Suggestion as an additional Penalty on Principal Components Estimation – with Application-
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This research deals with a shrinking method concernes with the principal components similar to that one which used in the multiple regression “Least Absolute Shrinkage and Selection: LASS”. The goal here is to make an uncorrelated linear combinations from only a subset of explanatory variables that may have a multicollinearity problem instead taking the whole number say, (K) of them. This shrinkage will force some coefficients to equal zero, after making some restriction on them by some "tuning parameter" say, (t) which balances the bias and variance amount from side, and doesn't exceed the acceptable percent explained variance of these components. This had been shown by MSE criterion in the regression case and the percent explained v

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Publication Date
Sat Jun 18 2022
Journal Name
Al-academy
طريقة عمل قالب رملي معالج مع مادة الرزن لإنتاج مصبوبات برونزية
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أن استخدام طريقة الشمع المفقود و الصب بالرمل كان ولا يزال ، قديماُ و تقنياته قديمة وغير مطورة لذا تم التركيز على طريقة الصب بالرمل الذي أعتاد الحرفيون ، غالباً على أستخدامه لسهولة عمله وتدني الكلفته ، ولكن تبقى هذه القوالب محدودة الإمكانيات و كفاءتها محدودة و تنهدم بسهولة ولا يمكن نقلها أو تحريكها من مكان لآخر .ولكن باستخدام مادة البولستر رزن كرابط مع رمل المقالبة هو العنصر الجديد الذي سيحسن كثي
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Publication Date
Sat Dec 31 2011
Journal Name
Al-khwarizmi Engineering Journal
The Estimation of Vibrational Energy of Two Coupled (Welded) Plates Using Statistical Energy Analysis
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This paper deals with a method called Statistical Energy Analysis that can be applied to the mechanical and acoustical systems like buildings, bridges and aircrafts …etc. S.E.A as a tool can be applied to the resonant systems in the circumstances of high frequency or/and complex structure». The parameters of S.E.A such as coupling loss factor, internal loss factor, modal density and input power are clarified in this work ; coupled plate sub-systems and explanations are presented for these parameters. The developed system is assumed to be resonant, conservative, linear and there is an equipartition of energy between all the resonant modes within a given frequency band in a given sub-system. The aim of th

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