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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 03 2017
Journal Name
Baghdad Science Journal
On the Connection between the Dynamical System and the Ellis Compactification with Transitive Pointed System
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In this paper, some relations between the flows and the Enveloping Semi-group were studied. It allows to associate some properties on the topological compactification to any pointed flows. These relations enable us to study a number of the properties of the principles of flows corresponding with using algebric properties. Also in this paper proofs to some theorems of these relations are given.

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Publication Date
Tue May 10 2011
Journal Name
Al-qadisiyah Journal For Science
Synthesis and Characterization of 2-amino -5-phenyl-1,3,4-Oxadiazole Complexes with Selected Metal Ions.
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The new bidentate ligand 2-amino-5-phenyl-1,3,4-oxadiazole (Apods) was prepared by the reaction of benzaldehyde semicarbazone with bromine and sodium acetate in acetic acid gave. The prepared ligand was identified by Microelemental Analysis, FT.IR, UV-Vis and 1HNMR spectroscopic techniqes. Treatment of the prepared ligand with the following selected metal ions (MnII, CoII, NiII, CuII and ZnII) in aqueous ethanol with a 1:2 M:L ratio, yielded a series of complexes of the general formula [M(L)2Cl2].The prepared complexes were characterized using flame atomic absorption, (C.H.N)Analysis, FT.IR and UV-Vis spectroscopic methods as well as magnetic susceptibility and conductivity measurements. Chloride ion content was also evaluated by Mohr metho

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Publication Date
Sun Sep 25 2022
Journal Name
Hiv Nursing
BIOSYNTHESIS OF SILVER / SILVER CHLORIDE NANOPARTICLES BY IRAQI PROPOLIS AND STUDY THE ANTI – BACTERIAL ACTIVITY
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Sliver / Sliver chloride is as old used from human but the sliver / sliver chloride nanoparticles have only recently been recogenized. They have used in medicin and agiculture. In the present study have been investigation the effecte biosynthesis Sliver / Sliver chloride nanoparticles as antibacterial by demonstrated that Ag / AgCl NPs arrest the growth of many bacterial: S.typhimurium, k. pneumonia. S. aureus, L.monocytogenes, B. Anthracis, E. coli, C. frundi, S. Pneumonia, P. Aeruginosa. The elements compestion and crystallization panal of biosynthesized nanoparticles were chracterazated by FTIR, XRD and SEM. From XRD, It is confirmed the synthesized nanoparticles contain Sliver / Sliver chloride elements. Synthesized Ag / AgCl NPs showed

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Publication Date
Thu Feb 10 2022
Journal Name
Iraqi Journal Of Science
Characteristics of AC. Conductivity and Dielectric Behavior of Cu0.5 Ti0.5 Hox Fe2-x O4 Ferrites
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Ferrites with the formula Cu0.5Ti0.5HoxFe2-xO4 (x= 0 and 0.09) were prepared by standard ceramic method. The powder mixtures were presintered at 900 oC for 5h. The final sintering of the pellets was performed at 1100 oC for 2 hrs. The dielectric properties and AC conductivity were measured at different temperatures over the frequency range 100Hz - 10MHz. The variation in dielectric constant with frequency revealed that dispersion is due to the Maxwell–Wagner type of interfacial polarization in accordance with Koop’s phenomenological theory. This ferrite showed high value of dielectric constant. At low frequencies the dielectric constant and dielectric loss factor was found to decrease with the increase in frequency and Ho addition. T

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Publication Date
Tue Sep 29 2020
Journal Name
Iraqi Journal Of Science
Hydrochemical Assessment of Groundwater and Some Springs in Qazaniyah Area, Diyala province, East of Iraq
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The Qazaniyah study included the analysis of 18 wells and 2 springs for the dry period in October 2018 and the wet period in April 2019, including the analysis of physical and chemical properties and the study of heavy elements (Fe, Zn, Cd, Pb, Ni and Cu).The results showed that the water wells and springs for the two periods are highly mineralized and characterized by low alkalinity and very high hardness. Water was fresh in some wells and salty in the others, whereas it was fresh in the springs. Most  of the wells had sodium chloride type, except the wells 12, 7, 6, and 5 which were of Calcium chloride type. The springs for both seasons had calcium chloride type. Based on the World Health Organization criteria ,  all the well

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
١١٦ Academic Specialization and its relationship to job performance of The officials ofBaghdad University Presidency
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The aims of this research is to investigate : The nature of academic specialization of the officials of Baghdad University Presidency , Level of job performance of the officials of Baghdad University Presidency through job performance appraisal form per year , Differences in the levels of job performance of the officials of Baghdad university presidency , according to the variables (sex , academic specialization , the current work , the duration between the date of graduation and the date of appointment , service duration) , The relationship of academic specialization of the officials of Baghdad university presidencywith their job performance . The researcher has followed the analytical descriptive mode to achieve the aims of this resear

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Publication Date
Sun Dec 03 2017
Journal Name
Baghdad Science Journal
The Innovative Method for Vaccine Preparation Against Multidrug Resistant and Virulence Acinetobacter baumannii Iraqi Isolates
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The expanding of the medically important diseases created by multidrug-resistant Acinetobacter baumannii warrants the evolve a new methodology for prevention includes vaccination and treatment. Totally of forty-five clinical isolates identified as A.baumannii were obtained from hospitalized patients from three hospital in Baghdad City during the period from February 2016 to August 2016. Followed by diagnosing using different methods. Every strain was tested for susceptibility testing also some important virulence factorswere detected. Two isolates were chosen for the immunization and vaccine model, the first one remittent for most antibiotics except one are too virulence (strong) and the second is less virulent and resistance (weak).Enzyme-

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Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Determination of Visfatin Level in Patients with Diabetes and Peripheral Neuropathy as Early Predicted Factor
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Peripheral neuropathy represents one of the common diabetic complications in patients with diabetes mellitus type 2 (DMT2). Peripheral neuropathy affects the feet, legs, hands, and arms. It was found that one-third to one-half of diabetics have peripheral neuropathy. The current study aimed to evaluate the level of visfatin in diabetic patient groups with or without peripheral neuropathy in comparison with healthy subjects to knowledge whether visfatin can be applied as a predictor factor for this type of disease complication. The study included 120 males and females ranging in age from 40 to 97 years old. (40 patients with type 2 diabetes, 40 patients with diabetic peripheral neuropathy, and 40 healthy people served as the control group

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Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
Effect of Alcoholic Catechin Extract on Hyperglycemia, Hyperlipidemia and Liver Functions in Alloxan Diabetic Mice
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The objective of this study is to estimate the effect of the hydro-ethanolic catechin extract toward blood glucose, lipid profile and liver functions in alloxan diabetic mice. 50 healthy mice (25-30 g) were divided into five groups of ten animals for each. Group A received normal saline as normal control group. To induce diabetes, alloxan (150 mg/kg), intraperitoneal (i.p.) single dose was injected to groups B, C, D and E. Group B represents diabetic control group. Groups C, D and E received ethanolic catechin extract (30 mg/kg and 40 mg/kg) for different periods of 1, 2 and 3 weeks as treated groups. Blood glucose, serum lipids [Total Cholesterol (TC), Triglycerides (TGs) and High Density Lipoproteins (HDL)], asparagine transaminase (AST),

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Crossref
Publication Date
Wed Dec 23 2020
Journal Name
Iraqi Journal Of Agricultural Sciences
THE TAXONOMICAL SIGNIFICANT OF COMPUTERD PHYLOGENETIC ANALYSIS AND MORPHOLOGICAL DATA IN SOME SPECIES OF POLYGONACEAE
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This research dealt with study of cladistics taxonomy of  five  species related to the genus Rumex L. and Polygonum L. from family polygonaceae in Iraq by using Mesquite software V.2.75. This  research support strongly delimiting  the species P. aviculare L. and P. lapathifolia L.as suggested in floras publication while R. dentatus L. is setted in single group whereas R. vesicarius L. and R. conglomeratus Murray were included in the same group. Also, this study involved characteristics of shape, dimensions, color, and ornamentation of seeds and fruits as  the seed forms were ranging from lenticular to trigonous. In terms of size calculations,  the seeds of R. vesicarius  was recorded the higher range (4.0- 4.5) mm in length w

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