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joe-1095
Pilot Based Channel Estimation and Synchronization in OFDM System
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Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less number of pilot to mitigate ISI effect. Channel estimation is simulated for different pilot number with 16QAM modulation in Ped-A Rayleigh channel. The STO effect assumed less than the cyclic prefix length to minimize ISI and maintain the orthogonality between subcarriers. The simulation results show that the high number of pilots are needed to achieve good channel estimation in case no synchronization used while similar results are achieved with smaller number of pilots if the propose modification on the synchronization method are used aligned with the channel estimation. The proposed system is evaluated in terms of BER and SNR.

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Influence of the Surrounding Plants by Rapeseed Field on Population Density of Cabbage Aphid (Brevicoryne brassicae L.) and its Biological Enemies
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The result revealed that the peak of population density of cabbage aphid Brevicoryne brassicae was 523.20 individuals/plant on 21 March in edges of rapeseed field and was 1141.67 individuals/plant in center of the field. Results revealed that population density of cabbage aphid in rapeseed fields surrounded by cover crops significantly were low compared with that of monoculture rapeseed. The location of rapeseed plants (in edges or in center) significantly affected (p<0.05) the tested pest density, e.g. optimum density was 146.69 individuals/plant in the center of the field. Whereas was 93.32 in the edges. Effect of the interaction between location and surrounding vegetation was significant on aphid density, which their population densit

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Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Impact of Islamic Financial Inspection Thought on the Development of Inspection and comparing it with Positive Thought: Theoretical Comparative Study
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You Mohammed, you're prophet of God and I'm Gabriel)). With this heavenly call which Mohammed, the messenger of God (may God's mercies be on him), got and when he left Hiraa cave and after getting the aye ((read with your God's name)), a new period of mankind's history started. From that time, the greatest state was established. There was no public treasury and no public financial resources at that time. Abu Baker (God bless him) spent a lot of money to support the costs of the new mission. After Al-Hijra, the bases of establishing the Islamic state were available but it lacked administrative and financial organizing. Therefore the prophet was very keen to find Islamic system which ensures justice and availability of

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Publication Date
Wed Apr 19 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Spectral Studies of Some Metal Complexes with Bis[O,O-2,3;O,O-5,6(Chlorocarboxylic Methyliden)] L-Ascorbic Acid
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&nbsp;The reaction of L-ascorbic acid with the tirchloroacetic acid in the presence of potassium hydroxide gave new product Bis[O,O-2,3;O,O-5,6(chlorocarboxylicmethyliden)]Lascorbic acid (H2L) which was isolated and characterized by 1H,13C-NMR, elemental analysis (C,H,N), UV-Visible and Fourier Transform Infrared (FTIR). The complexes of the ligand (H2L) with metal ions, M+2= (Cu, Co, Ni, Cd and Hg) were synthesized and characterized by FTIR, UV-Visible, molar conductance, atomic absorption, magnetic susceptibility and the molar ratio. The analysis evidence showed the binding of the metal ions with (H2L) through the bicarboxylato group manner resulting in six-coordinated metal ion. The TLC for (H2L) and complexes showed one spot for eac

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Publication Date
Wed Jan 01 2020
Journal Name
Systematic Reviews In Pharmacy
Impacts of the alcoholic extract and essential oil of Thymus vulgaris L. Against the causative agent of acne formation (Staphylococcus aureus)
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Medicinal plant life have performed an integral role in the development of human lifestyle being used as resources for the manufacturing of contemporary medicines, antibiotics. Microorganisms are responsible for many issues in industry and remedy because of biofilm formation. This study aimed to take a look at the results of Thymus vulgaris alcoholic extract on Staphylococcus aureus the causative marketers of acne in human particularly the women. The extract was acquired mixing 25 g of Thyme powder with 350 ml of 80% ethanol for 6 hours at 40°. Antimicrobial activities of the plant extract and integral oil towards the S. aureus were decided using the agar diffusion technique. The consequences proven that special concentrations of alcoholic

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Scopus
Publication Date
Sun Oct 12 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The validity of salivary microRNAs (hsa-miR-200a, hsa-miR-125a and hsa- miR-93) as oral squamous cell carcinoma biomarker
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Background: Oral squamous cell carcinoma represents the vast majority of oral cancer it is a common malignant tumor with an increasing incidence. Around the world, the 5 year mortality rate of oral cancer is about 50%. Thus novel biomarkers for early detection oral squamous cell carcinoma are needed. The level of three salivary microRNAs namely hsa-miR-200a, hsa-miR-125a and hsa- miR-93 were measured in saliva of patients with oral squamous cell carcinoma and compared their levels in saliva of healthy control subjects to determine their potential as oral cancer biomarker. Materials and methods: The level of these three microRNAs was measured by using revers transcription, preamplification and quantitative PCR. Results: Only miR-200a presen

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Publication Date
Mon Apr 06 2020
Journal Name
August
INFLUENCE OF SOME FACTOR ON SOMATIC EMBRYOS INDUCTION AND GERMINATION OF DATE PALM CV BARHI BY USING CELL SUSPENSION CULTURE TECHNIQUE
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Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Electrical Dielectric Authorship of Polyvinyl-Acetate and Toluene Diisocyanate (PVA-TDI) with Manufactured Sulfonated Phenol-formaldehyde (SPF) Viscous Mass Material Composite
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The electrical insulation of the manufacture sulfonated phenol-formaldehyde viscous material (product) has been studied with Polyvinyl-acetate (PVA) and toluene diisocyanate (TDI) blend has been prepared by fixing percentage by weight 3:1 and mixed with different percentages by weight of the product sulfonated phenol formaldehyde viscous mass (SPF). The Fourier transform infrared (FTIR) spectroscopy is done on (SPF) resin powder and prepared film of PVA-TDI-SPF viscous mass. The quality factor (Q), dissipation factor (D), parallel resistance (Rp), series resistance (Rs), parallel capacitance (Cp), series capacitance (Cs) and phase shift (?) are measured. The calculated maximum dielectric constant (??) is 3.49x107 at sample (1) wt.1% SPF vis

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Publication Date
Fri Jan 01 2021
Journal Name
Prepodavatel Xxi Vek
Enrichment of Vocabulary and the Formation of Grammatically Correct Speech of Foreign Students When Studying the Text of a Literary Work
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Publication Date
Tue Feb 21 2017
Journal Name
Journal Of Entomology And Zoology Studies
Comparison study between a crude bacterial suspension and purified pseudomonal alkaline protease enzyme effect on the rabbit interleukin-2 bacterial keratitis
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Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Physics
Study the Effect of annealing temperature on the Structure of a-Se and Electrical Properties of a-Se/c-Si Heterojunction
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In this work Study effect of annealing temperature on the Structure
of a-Se and electrical properties of a-Se/c-Si hetrojunction have been
studied.The hetrojunction fabricated by deposition of a-Se film on c-
Si using thermal evaporation.
Electrical properties of a-Se/ c-Si heterojunction include I-V
characteristics, in dark at different annealing temperature and C-V
characteristics are considered in the present work.
C-V characteristics suggested that the fabricated diode was
abrupt type, built in potential determined by extrapolation from
1/C2-V curve. The built - in potential (Vbi) for the Se/ Si System
was found to be increase from 1.21 to 1.62eV with increasing of
annealing temperature

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