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New Adaptive Data Transmission Scheme Over HF Radio
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Acceptable Bit Error rate can be maintained by adapting some of the design parameters such as modulation, symbol rate, constellation size, and transmit power according to the channel state.

An estimate of HF propagation effects can be used to design an adaptive data transmission system over HF link. The proposed system combines the well known Automatic Link Establishment (ALE) together with variable rate transmission system. The standard ALE is modified to suite the required goal of selecting the best carrier frequency (channel) for a given transmission. This is based on measuring SINAD (Signal plus Noise plus Distortion to Noise plus Distortion), RSL (Received Signal Level), multipath phase distortion and BER (Bit Error Rate) for each channel in the frequency list. Channel condition evaluation is done by two arrangements. In the first an FFT analysis is used where a pilot signal is transmitted over the channel, while the data itself is used in the second arrangement. Passive channel assessment is used to avoid bad channels hence limiting the frequency pool size to be used in the point to point communication and the time required for  scanning and linking. An exchange of channel information between the transmitting and receiving stations is considered to select the modulation scheme for transmission. Mainly MPSK and MFSK are considered with different levels giving different data rate according to the channel condition. The results of the computer simulation have shown that when transmitting at a fixed channel symbol rate of 1200 symbol/sec, the information rate ranges from 2400 bps using 4FSK up to 3600 bps using 8PSK for SNR ranges from 11dB up to 26dB.

 

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Publication Date
Thu Oct 20 2022
Journal Name
Nano Biomedicine And Engineering
DFT-Quantum Chemical and Experimental Studies of a New 2-(Substituted Thio) Furan as a Corrosion Inhibitor in Acidic Media
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The corrosion inhibiting properties of the new furan derivative 5-(furan-2-ylmethylsulfonyl-4-phenyl-2,4- dihydro [1,2,4] triazole-3-thione in acidic solution (1.0 M HCl) were explored utilizing electrochemical, surface morphology (AFM), and quantum chemical calculations approaches. The novel furan derivative 5-(furan-2-ylmethylsulfonyl-4-phenyl-2,4- dihydro [1,2,4] triazole-3-thione shows with an inhibitory efficiency value of 99.4 percent at 150 ppm, carbon steel corrosion in acidic medium is effectively inhibited, according to the results. The influence of temperature on corrosion prevention was studied using adsorption parameters and activation thermodynamics. The novel furan derivative creates a protective layer over the metallic surfa

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Publication Date
Tue May 01 2018
Journal Name
Journal Of Engineering
Performance enhancement of Echo Cancellation Using a Combination of Partial Update ( PU) Methods and New Variable Length LMS (NVLLMS) Algorithm
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In this paper, several combination algorithms between Partial Update LMS (PU LMS) methods and previously proposed algorithm (New Variable Length LMS (NVLLMS)) have been developed. Then, the new sets of proposed algorithms were applied to an Acoustic Echo Cancellation system (AEC) in order to decrease the filter coefficients, decrease the convergence time, and enhance its performance in terms of Mean Square Error (MSE) and Echo Return Loss Enhancement (ERLE). These proposed algorithms will use the Echo Return Loss Enhancement (ERLE) to control the operation of filter's coefficient length variation. In addition, the time-varying step size is used.The total number of coefficients required was reduced by about 18% , 10% , 6%

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Publication Date
Mon Jul 01 2024
Journal Name
Russian Journal Of Organic Chemistry
Synthesis and Study of the Biological Activity of New Compounds Derived from 4-(5-Phenyl-1,3,4-oxadiazole-2-yl)aniline
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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
The Islamic Regular Charity between The Immediacy and The Lagging
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The islamic legitimacy,imposition and of al-zakkat(regular charity) are well
known matters to the whole muslims but being in love with the present life and
worldly existence and being in scare of the death made some of the moslems to lag
behind and delay of keeping with that matter (regular charity) because the mony al
wayes was the reason for the man happiness in the present life allah makes al-zakat
(regular charity) one of the granting remissionns of the moslems people sins in return
for that allah promised the moslems to honored them with the eternal life in in the
paradise where is the gardens beneath which rivers flow so that I decided to write in
this matter of couarse after trust and recommend in god and h

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Publication Date
Tue Dec 01 2020
Journal Name
2020 5th Ieee International Conference On Recent Advances And Innovations In Engineering (icraie)
The New Way of Estimating the PCB's Lifetime of Fatigue using the Principle of Linear Accumulated Damage in Various Boundary Condition
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Publication Date
Wed Oct 02 2019
Journal Name
Biochem. Cell. Arch.
NEW MIXED LIGAND OF DITHIOCARBAMATE AND 8- HYDROXYQUINOLINE WITH SOME COMPLEXES OF SCHIFF BASE LIGAND : SYNTHESIS, SPECTRAL ANALYSIS AND BIOLOGICAL ACTIVITY
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The preparation, spectroscopic characterisation of complexes derived from the mixed ligands with CdII, ZnII and CoII metal ions with Schiff base, Dithiocarbamates (DTCs) and 8-Hydroxyquinoline are reported. The compounds that prepared have been defined via; chloride content, F.T-IR, UV-Vis 1H-NMR spectroscopy and C.H.N.S, as well as conductance and magnetic susceptibility.All data which collected from such methods specified complexes with 6 coordinates in solution and solid states. The biologicalactivity that is related to all the prepared compounds which were screened for their antimicrobial activitiesagainst (G+ and (G- )). The data that collected from biological activity indicate that complexes will have extra activity against such teste

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Publication Date
Sat Feb 21 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of different finishing and polishing systems on surface roughness of new low polymerized composite materials (An in vitro study)
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Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surfa

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Publication Date
Sun Nov 01 2015
Journal Name
Journal Of Dentistry
New functional and aesthetic composite materials used as an alternative to traditional post materials for the restoration of endodontically treated teeth
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Objectives To tailor composites of polyethylene–hydroxyapatite to function as a new intracanal post for the restoration of endodontically treated teeth (ETT). Methods Silanated hydroxyapatite (HA) and zirconium dioxide (ZrO2) filled low-density polyethylene (LDPE) composites were fabricated by a melt extrusion process and characterised using infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The flexural strength and modulus were determined in dry state and post ageing in simulated body fluid and fractured surfaces analysed by SEM. The water uptake and radiographic appearance of the experimental composites were also measured and compared with a commercially known endodontic fibre

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Publication Date
Thu Jun 27 2019
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
A SURVEY OF WEEVILS (COLEOPTERA, CURCULIONOIDEA) FROM SOME LOCALITES OF KURDISTAN REGION- IRAQ, WITH NEW RECORDS TO THE ENTOMOFAUNA OF IRAQ
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This work is the first study of the Curculionoidea fauna from Kurdistan region of Iraq, based on the intensive survey in different localities of Kurdistan from March 2016 to November 2017. In total, 41 species belonging to 28 genera, 21 tribes and 3 families were collected and identified, including 25 species newly recorded for the Iraqi fauna.

 

General distribution, collecting localities and methods, with plant association data for each species are given.

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Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
Detection a New Antiseptic Resistant Variant of qac Gene in Some Multi Drug Resistant Staphylococcus aureus Isolated from Different Clinical Sources
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The increasing use of antiseptic compounds creates selective pressure cause emergence of antiseptic resistance among Staphylococcus aureus .Resistance mechanism of antiseptic is driven mainly by multi drug resistant (MDR) efflux protein.Sixty five isolates of S.aureuswere collected from different clinical sources and subjected to 11 antibiotics most of them are recognized by efflux systems as extruded substrates. Range of efflux activity was estimated using cartwheel method. Simultaneous discrimination of antiseptic coding genes (qacA/B, smr and norA)as well as nuc and mecA genes among multidrug resistantS.aureus(MRSA) isolates was preformed using multiplex PCR assay

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