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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 Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Adsorption of NO2/N2O4 into Water and Dilute Nitric Acid in a Double Stirrer Adsorber
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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The effect of unsecured use of chemical pesticides on the environment and health in Iraq
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The wide use of pesticides in recent years leads to rapid distribution of these pollutants in the environment (air, water and soil).They were transported by means of air or water to biological ecosystems. They become more toxic through the processes of biological magnification while some of them persist for along period.The aim of this work is to show the negative effect that chemical pesticides causes, and in the same to show their side effect on the environment and health in Iraq. We could conclude that the bad use of these chemicals could cause an urgent impact now or in the future. Governmental offices dealing with these materials should take the right measures to minimize the danger and the misuse of these chemicals by seeking alternat

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Publication Date
Tue Oct 11 2022
Journal Name
College Of Islamic Sciences
Hanbali's approach to building long and short travel provisions with issues attached to their provisions
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The problem with research lies in hiding the Hanbali approach in building long and short travel provisions, as well as hiding some provisions relating to short travel that are not provided for by the jurists of Hanbali (in their books).

The research aims to demonstrate the approach and standards on which they based the long and short travel provisions, as well as to reflect the provisions of some of the issues that are silent on long and short travel, with evidence and significance.

The research included a preface and two researches, the researcher in the preface talked about the reality of long and short travel, in the first research on the approach of ha

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Publication Date
Sun Jan 01 2023
Journal Name
E3s Web Of Conferences
Comparing the Design Alternatives Using Building Information Model (BIM) and Constructability in Iraqi Construction Projects
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The Iraqi construction industry suffers from many issues that lead to many design errors, clashes, delays and cost overruns. Therefore, applying constructability will prevent these issues from happening, as it has proven its positive effect in different projects around the world. The goal of this paper is to use building information modelling (BIM) to assess the constructability, provide the opportunities for the project stakeholders to choose the best constructable design alternative and find the affection of applying constructability on project cost. The practical side of this research consists of two parts: in the first part, 37 factors are collected from the literature review as factors that effect on constructability. After tha

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
DIESEL PARTICULATE EMISSIONS EVALUATION FOR SINGLE CYLINDER ENGINE FUELLED WITH ETHANOL AND GAS-OIL SOLUTIONS
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Particulate matter (PM) emitted from diesel engine exhaust have been measured in terms of mass, using
99.98 % pure ethanol blended directly, without additives, with conventional diesel fuel (gas – oil),to
get 10 % , 15 %, 20 % ethanol emulsions . The resulting PM collected has been compared with those
from straight diesel. The engine used is a stationary single cylinder, variable compression ratio Ricardo
E6/US. This engine is fully instrumented and could run as a compression or spark ignition.
Observations showed that particulate matter (PM) emissions decrease with increasing oxygenate
content in the fuel, with some increase of fuel consumption, which is due to the lower heating value of
ethanol. The reduction in

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Publication Date
Sat Jan 30 2021
Journal Name
Iraqi Journal Of Science
Investigation of the Anti-cataract and Antioxidant Activities of Cnidoscolus aconitifolius Leaves Extract In vitro
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Background: Cataract is a major cause of visual impairment and blindness around the world. This study evaluated the in vitro antioxidant and anti-cataract activities of Cnidoscolus aconitifolius leaves extract and fractions. Antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiozoline-6-sulfonic acid) (ABTS), total reducing power, and hydrogen peroxide scavenging assays. Anti-cataract potential was evaluated in vitro using goat lenses divided into eight groups of different treatments and incubated in artificial aqueous humor at 37 °C for 72 hours. Glucose-induced opacity in the lenses was observed and biochemical indices quantified (cata

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Publication Date
Tue Jun 01 2021
Journal Name
Iraqi Journal Of Physics
Structural and optical properties of TiO2:NiO nanoparticles thin films prepare by chemical spray pyrolysis
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The properties of structural and optical of pure and doped nano titanium dioxide (TiO2) films, prepared using chemical spray pyrolysis (CPS) technique, with different nanosize nickel oxide (NiO) concentrations in the range (3-9)wt% have been studied. X-Ray diffraction (XRD) technique where using to analysis the structure properties of the prepared thin films. The results revealed that the structure properties of TiO2 have polycrystalline structure with anatase phase. The parameters, energy gap, extinction coefficient, refractive index, real and imaginary parts were studied using absorbance and transmittance measurements from a computerized ultraviolet visible spectrophotometer (Shimadzu UV-1601 PC) in the wavelength

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Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Particle-Hole State Density Calculations with Non-Equidistant Spacing Model: II. Pairing and Exact Treatment
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In an earlier paper, the basic analytical formula for particle-hole nuclear state densities was derived for non-Equidistant Spacing Model (non-ESM) approach. In this paper, an extension of the former equation was made to include pairing. Also a suggestion was made to derive the exact formula for the particle-hole state densities that depends exactly on Fermi energy and nuclear binding energies. The results indicated that the effects of pairing reduce the state density values, with similar dependence in the ESM system but with less strength. The results of the suggested exact formula indicated some modification from earlier non-ESM approximate treatment, on the cost of more calculation time

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Publication Date
Fri Jan 31 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Measurement of salivary Immunoglobulin A of participants with a healthy, gingivitis and chronic periodontitis conditions
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Background: Secretory Immunoglobulin A (SIgA) is a subclass of Immunoglobulin A (IgA), It is an antibody that plays an important role in mucosal immunity. It is the main immunoglobulin found in mucous secretions from mammary glands, tear glands and salivary glands, every pathologic process in the body involves the immune system, and periodontal inflammation is one of them and is not an exception. Material and methods: this study was consisted of 60 healthy male participants of an age ranged between (35-50) years old ; 25 of them with generalized moderate chronic periodontists(Clinical Attachment Loss equal to 3-4mm at ≥ 30% of the sites; 20 participants with plaque induced gingivitis and 15 participants had clinically healthy pe

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Publication Date
Thu May 04 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Morphological and Histological Study Of The Cerebrum In A Nocturnal Bird Species (Barn Owl)TytoAlba
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Morphological and histoarchitecture aspects on the cerebrum of (barn owl) were made
to find outthe cerebrum size, design and the description of cerebral region components at the
light microscopic level by using Haematoxylin – Eosin and periodic acid schift (PAS)
stain methods. The result of the morphological aspects revealed that the cerebrum was large
and an obtuse triangle in shape, its surface had a slight furrow. Sagittal sections revealed
the location, arrangement and size of pallial and subpallial cerebral divisions. The result of
the microscopic examinations indicated that the large and massive hyperpallium (wulst) was
thick,hypertrophied wired, and multilaminate structure reflect their wider ste

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