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Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

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Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Evaluation of Thyroid Hormones and Some Biochemical Variables in Patients with Chronic Kidney Disease
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Chronic kidney disease (CKD) is a permanent loss of kidney function which is diagnosed when the glomerular filtration rate (GFR) is under 60 ml\min\1.73m2 for more than three months. The present study was conducted at Kidney Transplant and Dialysis Center in the Medical City in Baghdad from October 2018 to April 2019. Sixty CKD patients with an age ranged of 40 to 65 years and 25 healthy subjects were involved in this study. Blood samples were collected to evaluate the levels of kidney function parameters and thyroid hormones. The levels of urea, creatinine and uric acid showed highly significant (p ≤ 0.01) increases in CKD patient in comparison with the control group, while the values of GFR and creatinine clearance showed highly

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Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Analysis and Study of the Effect of Atmospheric Turbulence on Laser weapon in Iraq
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One of the most important challenges facing the development of laser weapons is represented by the attenuation of the laser beam as it passed through the layers of atmosphere.This paper presents a theoretical study to simulate the effect of turbulence attenuation and calculates the decrease of laser power in Iraq. The refractive index structure C_n^2 is very important parameter to measure the strength of the atmospheric turbulence, which is affected by microclimate conditions, propagation path, season and time in the day. The results of measurements and predictions are based on the Kolmogorov turbulence theory. It was demonstrated by simulations that the laser weapons in Iraq were severely affected due to the large change in temperatures,

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Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
Evaluation of Physical Chemical and Biological Characteristics of Underground Wells in Badra City, Iraq
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The quality of groundwater should be improved by keeping safe water sources from contaminants in protective way by doing regular measuring and checkup before it supplied for usage. Private Wells do not receive the same services that wells supplying the public do. Well owners are responsible for protecting their drinking water. This work was carried out in Badra city, Iraq from December 2017 to May 2018, six wells water were investigated to determine the general characteristics of wells as well as studying the effect of environmental factors on the quality of water. The average of six wells were eleven parameters that is out of permissible limits were EC, Sal., Alk., TH, TDS, Na, Ca, Cl, SO4, Fe, Zn (4402-5183 /cm, 2.76-3.9 ppt

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Publication Date
Thu Oct 01 2009
Journal Name
Journal Of The Faculty Of Medicine Baghdad
C.T Scan Measurements of the Lateral and Third Ventricles in Apparently Normal Iraqi Subjects
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Background: Cerebral ventricular enlargement has been associated with many neurological disorders. Whether this enlargement is primary or secondary to these pathological conditions remains controversial. To define such enlargement, one must have measurements in normal subjects (controls).
Patients and methods: One hundred-twelve (66 male and 46 females) apparently healthy normal subjects, with age ranging between 10-69 years were subjected to C. T scans as part of routine diagnostic workup for complaint of headache or recent minor motor-vehichle accident The ratio (measured as percent) of the ventricular-cross area of the lateral ventricle The maximum width (MTW) of the third ventricle was also deter

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Publication Date
Mon Jan 02 2012
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Comparative study between ultrasound findings and intra-operative findings in non-traumatic Abdominal Pain:
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Background: acute abdominal pain is one of the most common presentations in surgical wards. Ultrasound has been grown in popularity as an easy, quick and non-invasive imaging the abdomen. US is very useful means of non-invasively, modality for assessment of acute abdominal pain.
Objective: Study of the most common acute none traumatic abdominal diseases in adult patients admitted to Baghdad Teaching Hospital in department of surgery .Correlate the operative findings with sonographic features as to make the initial diagnosis of the diseases included in this study. Compare the diagnostic yield of abdominal ultrasound with that of computed tomography (CT).
Methods :The present study included eighty nine consec

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Publication Date
Sun Oct 18 2020
Journal Name
Al-kindy College Medical Journal
Management of COVID-19 in Children and Adolescents -A Practical Up-to Date Guideline
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Sufficient high-quality data are unavailable to describe the management approach and guideline of COVID-19 disease in pediatric and adolescent population which may be due to mild presentation in most of cases and less severe complications than older ages.

World Health Organization was concerned with the establishment of an approved guideline to manage the increasing number of COVID-19 patients worldwide aiming to prevent or lessen COVID-19 global burden.

The clinical features have a wide spectrum starting from uncomplicated mild illness, mild-moderate pneumonia, severe pneumonia, acute respiratory distress syndrome, sepsis, septic shock, and multisystem inflammatory syndrome in children.

Many important definitions

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Publication Date
Thu Jan 24 2019
Journal Name
Al-kindy College Medical Journal
Role of MRI diffusion weighted imaging in differentiation between benign and malignant ovarian masses
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Background: Characterization of the ovarian masses preoperatively is important to inform the surgeon about the possible management strategies. MRI may be of great help in identifying malignant lesion before surgery. Diffusion Weighted Imaging (DWI) is a sensitive method for changes in proton of water mobility caused by pathological alteration of tissue cellularity, cellular membrane integrity, extracellular space perfusion, and fluid viscosity.

Objective: to study the diagnostic accuracy of DWI in differentiation between benign and malignant ovarian masses.

Type of the study:Cross-sectional study.

Methods: this study included  53with complex

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Publication Date
Wed Jul 01 2015
Journal Name
Al–bahith Al–a'alami
Building the News Agenda in Iraqi Newspapers and Patterns of Bias in their Sources
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News are considered the most press arts that supply the target audiences with daily information and events happened inside and outside society since it is formed by depending on its resources which have a deep relation with formal corporations to gain their satisfaction in order to support their authority and spreading their domination by using mass media in editing their viewpoints and achieving wide acceptance among public opinion. In the field of technological development and changing in the fields of politics, society, culture, economics etc. inside Iraqi society and democratic transition help to convert news agenda from independent variation to a fellow variation while in the past the variation of mass media was the independent one

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Publication Date
Sun Jan 03 2016
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Aortic root dilatation among children with unoperated Fallot tetralogy. A clinical and echocardiographic study.
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Bacground: Tetralogy of Fallot (TOF) is a commn congenıtal heart disease and it may be associated with aortic root dilation (ARD ) before or even years after the surgical repair. To the best knowledge this is the first study in Iraq dealing with this issue.
Objectives : To dtermine the frequency of aortic root dilatation among sample of children with Fallot teralogy in Mosul-İraq and to asses its associated risk factors.
Patients and methods : A total of 110 children ,54 with TOF compared to 56 normal chıldren by echocardiography for determining the frequency of aortic root dilatation among both groups. Among TOF children different factors like age and sex, size of the ventricular sptal defect (VSD) ,degree of overrıdıng of ao

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Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
Analytical Study of Crude Oil Price Shocks in the Global, Market Reasons and Result
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The global oil market is one of the most important markets in the world and occupies especially for countries consuming and producing countries, and the status of understanding of the mechanism for determining prices in the market help to stand on many factors affecting oil demand and supply of oil and geopolitical factors, climate and alternative sources of energy .. etc. factors, and that the main objective of the research is to study the causes and results left behind by the oil price shocks in the world market, and the movement of these factors be through a cycle of energy that explain the strength of competition between these factors and their effects on prices, when demand increases evolution Large image leads to significan

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