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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 Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Discipline in the classroom (problems and solutions)
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Research Summary

First: the problem of research and its importance

      The teacher's success in facilitating the students' learning and growth according to the educational and educational goals set out, he must identify the problems of discipline of students in the classroom in terms of sources and reasons and types and methods of prevention and treatment and the teacher to remember that success in his teaching and instruction is not completed more fully once he has the information And knowledge of the subject of the lesson, but must understand the dynamics of the group (class group) and master the skills of classroom management, su

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Publication Date
Sun Dec 01 2002
Journal Name
Iraqi Journal Of Physics
FLUORESCENCE LIFETIME MEASUREMENT OF C5H6 AND C6D6
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Absorption and lifetime measurements were made for C6H6. and C6D6 molecules in pure solid phase and in solid matrices of Ar, N2, CO, and CO2. All measurement are made at low temperatures ranging between 12-50 K. A modified least square fitting deconvolution was utilized to measure the fluorescence lifetime with an error less than 1%. The results show that the use of matrix isolation technique offer a unique environment that minimize the perturbation of the molecular or atomic system and hence facilitate spectral analysis.

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Publication Date
Thu Dec 09 2021
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Cressa cretica Pharmacognosy, and Pharmacology (A review )
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Cressa cretica (Shuwwayl) is a halophytic that belongs to Convolvulaceae, naturally grown in the Middle East including Iraq. Traditionally the plant is used as a paste for sore treatment, also it is used for fever, jaundice, and other illness. Regarding nonclinical use it is used as goat, sheep, and camel feed also as an oil source. Flavonoids including quercetin, kamepferol, apigenin, and their glycosides, phenolic acid as chlorogenic acid, and phytosterols mainly ?–sitosterol were the most important phytochemicals that were detected in this halophyte. Crude ethanolic, methanolic extracts and ethyl acetate fraction of the areal parts were used in clinical studies and demonstrated various effe

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Publication Date
Thu Feb 23 2023
Journal Name
Chalcogenide Letters
Fabrication and evaluation of CuAlSe2/Si photodetector
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In this work, we have examined the spectral response of (p-CuAlSe2/n-Si) detector, (CAS) thin films deposited by thermal evaporation at RT with a thickness (450) nm, and annealing temperature at (473K) for 2 h. Optical transmission measurements displayed reasonably slight transmission besides higher absorbance trendy the visible region, energy gaps were observed by annealing, were found to be direct, and decreased with the effect of annealing. The extreme responsivity value arises at wavelength 459 nm, with improvement value of specific detectivity and quantum efficiency the annealing films be situated originate as greatest suitable aimed at numerous device application.

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Publication Date
Sat Oct 19 2024
Journal Name
European Journal Of Human Genetics
Epigenomic and phenotypic characterization of DEGCAGS syndrome
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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Early Baldness in Males and Hormonal Changes
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Androgenetic alopecia (AGA) or baldness is a common form of hair loss, affecting men more than women .The exact causes and pathogenesis of baldness are not well understood. A search for new drug is still needed. This study aims to evaluate the role of gonadotropins hormones in hair loss in males and its possibility to be used as treatment target. A total of 78 volunteers 43 with baldness and 35 healthy men were participated in this study. Their age ranged between (20-49) years, the studied groups were divided into two categories: firstly according to age (group1: 20-29 year), (group2: 30-39 year),and (group3: 40-49 year).Secondly according to baldness degree. LH and FSH were measured by using Enzyme Linked Immunosorbent Assay (ELISA) kits.

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of The College Of Education For Women
Baghdadin Drinks and Foods stuff Abbasyat Ages
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Baghdadin Drinks and Foods stuff Abbasyat Ages

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Publication Date
Sun Mar 06 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of 3 - Substituted Coumarin
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The reaction of(2-oxo-2H-chromen-3-Carbonyl chloride)(k1) with hydrazine in boiling ethanol gives the hydrazide(K2).When compound (k2) reacts with various aromatic aldehydes ,the corres ponding Schiff bases(k3–k4) achieve new series of thiazotidines (k5–k6) and azetidinones (k7–k8) obtained from the reactions of appropriate Schiff bases with mercapto acetic acid and chloro acetyl chloride respectively. All the compounds are characterized by FT-IR,1H-NMR and GC-Ms.

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Publication Date
Thu Sep 28 2023
Journal Name
History Of Medicine
Pregnancy and left ventricular remodeling: Echocardiography parameter
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Profound maternal hemodynamic changes occur in order to satisfy the demands of a growing foetus. Early in pregnancy, peripheral vascular resistance (PVR) lowers, generating a considerable rise in cardiac output. Many parameters are employed for measuring the LV systolic function with different echocardiographic modalities including: M-Mode echocardiography, two-dimensional echocardiography, three-dimensional echocardiography, tissue doppler imaging.

Publication Date
Sat Jan 01 2022
Journal Name
Middle East African Journal Of Ophthalmology
Obstacles and challenges facing Iraqi women ophthalmologists
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