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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 03 2024
Journal Name
Pharmacia
Synthesis and preliminary antimicrobial evaluation of new 7-amino-4-methyl-coumarin thiazolidinone conjugates
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Abstract As a part of our ongoing project on the design and synthesis of new 4-thiazolidinone derivatives with antimicrobial activity, four new 4-thiazolidinone derivatives carrying bromo, nitro, methyl, and chloro groups on the benzene ring were synthesized by starting with the 7-amino-4-methylcoumarin moiety, linking coumarin with various phenyl isothiocynate to form the thiourea group, and then cyclizing the derivatives, characterized by IR and 1HNMR, and assayed in vitro for their antimicrobial activity against Gram positive and Gram negative bacteria and fungi. Overall, 2-(4-methyl-2-oxo-2H-chromen-3-yl)-3-(4-nitrophenyl) thiazolidin-4-one to be the most powerful individuals in the series. Based on the observed data, it can be sta

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Publication Date
Sat Aug 01 2020
Journal Name
Journal Of Engineering
New Approaches of Cloud Services Access using Tonido Cloud Server for Real-Time Applications
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A Tonido cloud server provides a private cloud storage solution and synchronizes customers and employees with the required cloud services over the enterprise. Generally, access to any cloud services by users is via the Internet connection, which can face some problems, and then users may encounter in accessing these services due to a weak Internet connection or heavy load sometimes especially with live video streaming applications overcloud. In this work, flexible and inexpensive proposed accessing methods are submitted and implemented concerning real-time applications that enable users to access cloud services locally and regionally. Practically, to simulate our network connection, we proposed to use the Raspberry-pi3 m

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Publication Date
Tue Jun 01 2021
Journal Name
Bulletin Of Electrical Engineering And Informatics
A new pseudorandom bits generator based on a 2D-chaotic system and diffusion property
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A remarkable correlation between chaotic systems and cryptography has been established with sensitivity to initial states, unpredictability, and complex behaviors. In one development, stages of a chaotic stream cipher are applied to a discrete chaotic dynamic system for the generation of pseudorandom bits. Some of these generators are based on 1D chaotic map and others on 2D ones. In the current study, a pseudorandom bit generator (PRBG) based on a new 2D chaotic logistic map is proposed that runs side-by-side and commences from random independent initial states. The structure of the proposed model consists of the three components of a mouse input device, the proposed 2D chaotic system, and an initial permutation (IP) table. Statist

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Publication Date
Sat Jan 01 2022
Journal Name
Aip Conference Proceedings
Design and simulation of a new system for producing laser beams without resonator “NSPLBR”
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Publication Date
Wed Oct 07 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Synthesis and Study the Biological Activity of New Heterocyclic Compounds Derived From Hydrazide Derivatives
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Publication Date
Fri Dec 01 2017
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
NEW RECORD OF THE PARASITOID WASP MONODONTOMERUS OBSCURUS WESTWOOD, 1833 (HYMENOPTERA, TORYMIDAE) IN IRAQ
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    This article reveals the first record of the parasitoid wasp, Monodontomerus obscurus Westwood (Hymenoptera, Torymidae) from Iraq.  A total of 27 specimens were emerged from mud nests of sphecoid wasp of Sceliphron sp. (Hymenoptera, Sphecidae), that collected from a wall at a residential garden in Dohuk province.  A short morphological description is presented.

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Publication Date
Sun Jun 01 2025
Journal Name
Iraqi Journal Of Pharmaceutical Sciences
Modified Polyvinyl Alcohol Containing New Imides / Iron Oxide Nanoparticles :Synthesis , Characterization and Biological Evaluation
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A series of new imides compounds[1-4] were synthesized from reaction of tetrachlorophthalic anhydride or nitro phthalic anhydride or malic anhydride or Succinic anhydride with 4-amino benzene thiol under fusion conditions. Chloroacetic acid has been added after compounds [1-4] reacted with distilled H2O and Na2CO3, producing compounds [5-8]. In benzene, compounds [5-8] also interacted with the thionyl chloride to produce [9-12]. Poly (vinyl alcohol) was chemically modified by reacting PVA with compounds [9-12] and dimethyl formamide to produce compounds [13-16]. Iron oxide nanoparticles (IONPs) are mixed with modified PVA [13-16] to create nanocomposites [17-20]. Spectral and analytical data from synthesized compounds, such as 1H-NMR, FTI

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Publication Date
Wed Apr 01 2026
Journal Name
Journal Of Nanostructures
Synthesis of New Polymeric Composite Materials Derived from 2,2-(1,6-Dioxohexane-1,6-diyl) Dihydrazinecarbothioamide
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In this study, a new class of polymeric nanocomposites was synthesized and characterized.  One mole of dimethyl adipate and two moles of thiosemicarbazide in ethanol first reacted to form the compound [C1]. Compound [C1] then reacted with sodium hydroxide to produce compounds [C2]. Hydrazine hydrate reacted with compound [C2] to generate compound [C3]. Compound [C4] was synthesized from compound [C3] and maleic anhydride. A polymer [C5] is formed by the reaction of the compound [C4] with ammonium persulfate as an initiator. This polymer was then combined with nano: ZnNPs, AgNPs, SiNPs, or IONPs using a hotplate stirrer for 3 hours to produce nanocomposites [C6-C9]. FTIR, 1H-NMR, and Field Emission Scanning Electron Microscope (FESEM) were

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Publication Date
Tue Jul 01 2003
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DESCRIPTION OF THREE NEW SPECIES OF THE GENUS ANTHRENUS GEOFFORY (COLOEOPTERA, DERMESTIDAE) FROM IRAQ
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The present work represents description of three new species of genus Anthrenus
Geoffory from Iraq, these are : A. aradensis sp. nov., A. fabrici sp. nov. and A.
unicolor sp. nov. Locality, host plants and date of collection were given.

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Publication Date
Sat Jan 01 2022
Journal Name
P J M H S
Synthesis and Characterization of Some New Metals Complexes of ((4 Methoxy Benzoyl) Carbamothioyl) Glycine
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A new ligand ( 4- methoxy benzoyl ) carbamothioyl ) Glycine (MCG) is synthesized by reaction of (4- methoxy benzoyl isothiocyanate) with Glycine(1:1). It is characterized by micro elemental analysis (C.H.N.S.), FT-IR, (UV-Vis) and 1H and 13CNMR spectra. Some metals ions complexes of this ligand were prepared and characterized byFT-IR,UV-Visible spectra, conductivity measurements, magnetic susceptibility and atomic absorption. From results obtained, the following formula [M(MCG)2] where M2+ = Mn, Co, Ni, Cu, Zn, , Cd and Hg, the proposed molecular structure for these complexes as tetrahedral geometry, except copper complex is has square planer geometry.