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alkej-590
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
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Designand Implementation of New DES64X and DES128X on 32, 64 Bit Operating System Environments
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In this paper, a description of a design for new DES block cipher, namely DES64X and DES128X. The goals of this design, a part of its security level, are large implementation flexibility on various operating systems as well as high performances. The high level structure is based on the principle of DES and Feistel schema, and proposes the design of an efficient key-schedule algorithm which will output pseudorandomsequences of subkeys. The main goal is to reach the highest possible flexibility, in terms of round numbers, key size, and block size. A comparison of the proposed systems on 32-bit, 64-bit operating system, using 32-bit and 64-bit Java Virtual Machine (JVM), showed that the latter has much better performance than the former.

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Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Agricultural And Statistical Sciences
USING A NEW METHOD TO INDUCE TARGETED GENETIC MUTATIONS IN POTATO VIRUS Y (PVY)
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Scopus (6)
Scopus
Publication Date
Thu Jun 27 2019
Journal Name
Molecular Crystals And Liquid Cryst
A New Series of Triazine-core Based Mesogenic Derivatives: Synthesis, Characterization and Mesomorphic Study
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The synthesis, characterization and mesomorphic properties of two new series of triazine-core based liquid crystals have been investigated. The amino triazine derivatives were characterized by elemental analysis, Fourier transforms infrared (FTIR), 1HNMR and mass spectroscopy. The liquid crystalline properties of these compounds were examined by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). DSC and POM confirmed nematic (N) and columnar mesophase textures of the materials. The formation of mesomorphic properties was found to be dependent on the number of methylene unit in alkoxy side chains.

Scopus (10)
Scopus
Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Synthesis and Characterization of New Polyimide by Curing Poly Acryloyl Chloride with Different Amides
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The present work involved preparation of new substituted and unsubstituted and poly imides (1-17) using reaction of acryloyl chloride with different amides (aliphatic ,aromatic) in the presence of a suitable solvent and amount tri ethyl amine (Et3N) with heating – the structure confirmation of all polymers were proved using FT-IR,1H-NMR,C13NMR and UV spectroscopy ,thermal analysis (TG) for some polymers confirmed their thermal stabilities . Other physical properties including softening and melting points, PH and solubility of the polymers were also measured

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Crossref (1)
Crossref
Publication Date
Mon Aug 18 2025
Journal Name
Journal Of Genetic And Environment Conservation
Ultrasound application as a new green technology for preservation of table eggs: A review
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In recent years, there has been a significant increase in research demonstrating the new and diverse uses of non-thermal food processing technologies, including more efficient mixing and blending processes, faster energy and mass transfer, lower temperature and selective extraction, reduced thermal and concentration gradients, reduced equipment size, faster response to extraction control, faster start-up, increased production, and a reduction in the number of steps in preparation and processing. Applications of ultrasound technology have indicated that this technology has a promising and significant future in the food industry and preservation, and there is a wide scope for its use due to the higher purity of final products and the

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Publication Date
Tue Dec 01 2009
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
A NEW SPECIES OF THE GENUS POLLENIA ROB.-DESVOIDY, 1830 (DIPTERA : CALLIPHORIDAE) FROM IRAQ
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This research includes a detailed morphological description of the Pollenia mesopotamica sp. nov. in Iraq. Locality, host plant and data of collection were given.

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Publication Date
Sun Mar 03 2013
Journal Name
Journal Of Al-nahrain University
Synthesis and Characterization of Some New 1,2,3-Triazole, Pyrazolin-5-one and thiazolidinone Derivatives
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Five membered heterocyclics derivatives were synthesized in this work by three routes. The first route includes the synthesis of N-benzoic acid 1,2,3,-triazole derivatives (3),(4) by diazotation of methyl-2-amino benzoate and treating the resulted salt (1) with sodium azide and ethyl acetoacetate or acetyl acetone, respectively. In the second route, derivatives of pyrazole (8) pyrazolin-5-one (9), (10) were prepared by the reaction of the salt (1) with some active methylene compounds to give the corresponding hydrazones derivatives (5-7) which then they were treated with hydrazine hydrate. The third route afforded the synthesis of three derivatives (12), (15a), (15b) of thiazolidinone by two different methods. AII compounds were confirmed b

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Publication Date
Tue Feb 12 2013
Journal Name
International Journal Of Engineering Sciences And Research Technology
Synthesis, Characterization of New Azo Compounds and Studies Effect on the Ach Enzyme(Invitro)
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Three azo compounds were synthesized in two different methods, and characterized by FT-IR, HNMR andVis) spectra, melting points were determined. The inhibitory effects of prepared compounds on the activity of human serum cholinesterase have been studied in vitro. Different concentrations of study the type of inhibition. The results form line weaver-Burk plot indicated that the inhibitor type was noncompetitive with a range (33.12-78.99%).

Publication Date
Sun Aug 25 2024
Journal Name
University Of Samarra
Preparation, diagnosis and testing of the biological ‎activity of new complexes of Schiff bases
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‎ Sixteen new complexes with the general formula [M(L)2(H2O)2] were ‎prepared resulting from the reaction of the two new Schiff base ligands, which ‎are‏: -‏ L1= (E)-5-((2-hydroxybenzylidene)amino)-2-phenyl-2,4-dihydro-3H-pyrazol-3-one)‎ L2 = (E)-5-((2-hydroxy-3-methoxybenzylidene)amino)-2-phenylpyrazolidin-3-one) ‎ ‎ With divalent metal ions (manganese, cobalt, nickel, copper, zinc, cadmium, ‎mercury) and (tetravalent platinum).‎‏ ‏ ‎ Ligands was derived from the reaction of the amine (5-amino-2-phenyl-2,4-‎dihydro-3H-pyrazol-3-one) with Salicylaldehyde and ortho-vanillin, which is ‎linked to the metal ions via the nitrogen atoms are the isomethene group and ‎the oxygen is the hydroxide group of t

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Synthesis And Characterization Of Some New Acetylenic Mannich Bases Based On Biphenyl – 4,4 - Dithiol
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One of the most important , compound which have active hydrogen is the compound possessing (thiol group) Biphenyl-4,4-dithiol is agood example utilized in a wide field for preparation mannich bases , avariety of new acetylenic mannich bases have been Synthesized and all proposed structure were Supported by FTIR , 1H – NMR, 13C-NMR , Elemental analysis and microbial study .

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