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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
Sun Jul 29 2018
Journal Name
Iraqi Journal Of Science
Environmental assessment of heavy metals in surface and groundwater at Samarra City, Central Iraq
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Urban Samarra City is characterized by high population density and wide variation in land use, has led to many environmental problems, for this purpose the environmental assessment became an urgent need for surface and ground water at study area. Three water samples from Tigris River   and six  groundwater samples were collected and analyzed for heavy metals  as Fe, Mn, Zn, Cd, Cu, Co ,Pb, Ni, Cr, As, Mo, Hg, Al, Li, Be, Se, V, U, Sr. Most heavy metal concentrations have shown higher level than standards, such as  Fe, Mn, Cd, Pb, Ni, Cr, As, Mo, Hg, Al ,Li ,Be, Se, V,  that might be due to anthropogenic activities such as  agricultural and the heavy  use of fertilizers, besides other activities amo

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Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Interactions Investigation of New Composite Material Formed from Bauxite and Melamine-Urea Formaldehyde Copolymer
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In this study the Bauxite has been activated and used to prepare two complexes: Bauxite - urea and Bauxite - melamine, these complexes were merged and polymerized with formaldehyde to prepare the complex Bauxite polymer - urea - melamine - formaldehyde (modified Bauxite). In the Bauxite-urea complex XRD results indicate that the urea molecules penetrate among the layers of the crystal plane (110) of the Gibbsite mineral while in the Bauxite-melamine the interaction was at the outer surface of the Bauxite forming minerals because the relatively large volume of the melamine molecule. FT-IR results show the interaction of these two bases with Bauxite was mainly based on the hydrogen bonding and in less extent on the coordination between N l

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
(Novels) Idiom , evolution and properties in the light of critic Shugaa Muslim Al-Aani
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A critics ,Shugaa Muslim Al-Aany, has specific critical principles in his branch
classifications for the type of the novel that is linked with its sources and what is adopted
of critical approaches and curriculums. The novel by its type as a literary one has
occupied Al-Any's critical importance very much ,he has divided it historically according
to its historical development ,the impact of dr.Abd Al-Muhassen Tha Badr's divisions on
Al-Any cannot hidden.
In his speech about the origin of novel and story art generally , Al-Any becomes
between the acknowledgement of the affect of Al-Mgma in rising of this art and denied its
affect at last. He has classified the novel also as a stylistic classification:(an impression

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Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
Physiological and Histopathological Effects of Abetacept (Orencia) Drug on Liver of Albino Male Mice
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A study investigated the effects of abetacept (Orencia) drug on the level of liver enzyme and on liver histology in albino male mice. Fourty five adult male mice of 8 weeks age and weighting 25-35g divided into three groups (15 mice each). The second & third groups were treated with abetacept drug while the first group was used as a control.
Abetacept was intraperitoneally given twice every week at 125 mg/kg B.W. and 250 mg/kg B.W. to the second and third groups respectively for 6 weeks, whereas the control group was intraperitoneally injected with normal saline. The results showed a significant (p< 0.05) increase in the levels of liver enzymes [serum alanine aminotransaminase (ALT), serum aspartate aminotransaminase (AST) &amp

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Publication Date
Sun Mar 15 2020
Journal Name
Al-academy
Time and Design Construction for Costumes in the Iraqi Theater Show: محمــود جبــاري حــافظ
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The theatre costume with the rest of the theatre show elements constitute a system of the meaning relations that produce a visual image that helps the recipient to decipher the theatre scene, let alone the manifestation of time in its levels (past, present, future) through the design construction of the theatre elements among which is the theatre costume. In order to know the way of manifesting time through the formulation of the theatre costumes, the research question has been put as follows:  how to manifest time through the design construction for the theatre costumes unit, from which the research objective is derived as follows: Revealing the possibility of the designing unit of the costumes in manifesting the levels of time wit

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Publication Date
Mon Jan 01 2024
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Prevalence of Anxiety and Depression Symptoms among Post Bariatric Surgery Patients in Baghdad-Iraq
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Background: Obesity is a major public health concern and is on the rise worldwide. Numerous studies revealed that the best method for treating morbid obesity is bariatric surgery, which has indicated its effectiveness in controlling weight. Published studies reported that patients who had undergone bariatric surgery may have psychiatric illnesses when compared to other obese individuals with similar preoperative characteristics.

Objectives:  Estimate the rates of anxiety and depression among post-operative bariatric surgery patients.

J. Fac. Med. Baghdad

2023. Vol 65, No. 4

 

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Sorption of Lead, Zinc and Copper from Simulated Wastewater by Amberlite Ir-120 Resin
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The presence of heavy metals in the environment is major concern due to their toxicity. In the present study a strong acid cation exchange resin, Amberlite IR 120 was used for the removal of lead, zinc and copper from simulated wastewater. The optimum conditions were determined in a batch system of concentration 100 mg/L, pH range between 1 and 8, contact time between 5 and 120 minutes, and amount of adsorbent was from 0.05 to 0.45 g/100 ml. A constant stirring speed, 180 rpm, was chosen during all of the experiments. The optimum conditions were found to be pH of 4 for copper and lead and pH 6 for zinc, contact time of 60 min and 0.35 g of adsorbent. Three different temperatures (25, 40 and 60°C) were selected to investigate the effect

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Crossref (5)
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Publication Date
Wed Dec 14 2022
Journal Name
Journal Of The College Of Languages (jcl)
Effective Metadiscourse Strategies in Texts of English and Arabic Trade Agreements to attain persuasion
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Persuasion is a process studied by many scholars from the Greek time until the present. One persuasion strategy is metadiscourse, which refers to the writers' awareness of their text, the way they present themselves to the readers. The writers use metadiscourse markers to help the readers understand the real meaning of the text (Hyland 2005).  The paper carries out a qualitative and quantitative analysis of the employment of persuasive metadiscourse markers in two English trade agreements and two Arabic agreements has provided in terms of Hyland's (2005) model of interactive and interactional markers. The aim is to find out whether all types of metadiscourse markers are used or not, and also to see whether English or Arabic employs

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Crossref (1)
Crossref
Publication Date
Mon Jan 02 2006
Journal Name
Journal Of The Faculty Of Medicine Baghdad
protien energy malnutrition in Iraqi children before and after five years of the san
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Background:

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
Analysis of Precipitation and Precipitable Water Vapor over Iraq for the Period 1948-2011
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The water vapor is one of the constituent elements of the rain and the superiority
of its importance in the study of climate because it is the basis on which depends all
the different aspects of condensation. The purpose of research is to analyze the time
series of the Baghdad station andan analyze these series to see whether there is a
relationship between these two variables. Obtained the data used in this research
from the National Center for Environmental Prediction for the period from 1948 to
2011. The use of statistical criteria included linear regression and Mann Kandal test
to find the link. The results of time series monthly presence decrease in rainfall and
all months except October, either the results o

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