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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
Wed Jul 01 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis, Design, Docking and biological activity of new benzo hydrazide derivatives.
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Publication Date
Wed Nov 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
New Record with Revision of Nomiinae Bees (Hymenoptera: Halictidae) in Iraq
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Abstract<p>In this study the Sub family of Nomiinae Robertson,1904 (Hyminoptera: Halictidae) was revised There were five species registered in our investigation: <italic>Pseudapis edentata</italic>(Morawitz,1876), <italic>P. nilotica</italic> (Smith,1976), <italic>Nomiapes bispinosa</italic> (Bulle,1832), <italic>N. diversipes</italic> (Latreille,1806), <italic>N. fugax</italic> (Morawitz1877); the last species is newly recorded in Iraq. A Key to identify the genera and species was designed according to the important morphological characters; as well, a brief description of the new record species is provided.</p>
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Publication Date
Fri Nov 24 2017
Journal Name
Journal Of Engineering
A new analytic method to tune a fractional order PID controller
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This paper proposes a new method to tune a fractional order PID controller. This method utilizes both the analytic and numeric approach to determine the controller parameters. The control design specifications that must be achieved by the control system are gain crossover frequency, phase margin, and peak magnitude at the resonant frequency, where the latter is a new design specification suggested by this paper. These specifications results in three equations in five unknown variables. Assuming that certain relations exist between two variables and discretizing one of them, a performance index can be evaluated and the optimal controller parameters that minimize this performance index are selected. As a case study, a third order linear time

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Publication Date
Thu Jun 25 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Synthesis, Characterization and Antibacterial Activity Evaluation of New Indole-Based Derivatives
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A new series of N-acyl hydrazones (4a-g) derived from indole-3-propionic acid (IPA) were synthesized. These N-acyl hydrazones were prepared by the reaction of 3-(1H-indol-3-yl) propane hydrazide and aldehyde in the existence of glacial acetic acid as a catalyst. 1HNMR and FT-IR analyses were used to identify the synthesized compounds and they were in vitro evaluated as antibacterial agents against six different types of microorganisms by using well diffusion method. All the tested N-acyl hydrazones (4a-g) displayed moderate activity against the Gram-negative E.coli, comparable to that of Amoxicillin. Some of the tested N-acyl hydrazones also exhibited intermediate activity ag

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Publication Date
Sun Dec 01 2019
Journal Name
Applied Soft Computing
A new evolutionary multi-objective community mining algorithm for signed networks
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Publication Date
Fri Aug 01 2014
Journal Name
International Journal Of Engineering And Innovative Technology (ijeit)
New Predictive Block Matching Searching Algorithms and Hybrid Predictive Search System
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In this paper, two new simple, fast and efficient block matching algorithms are introduced, both methods begins blocks matching process from the image center block and moves across the blocks toward image boundaries. With each block, its motion vector is initialized using linear prediction that depending on the motion vectors of its neighbor blocks that are already scanned and their motion vectors are assessed. Also, a hybrid mechanism is introduced, it depends on mixing the proposed two predictive mechanisms with Exhaustive Search (ES) mechanism in order to gain matching accuracy near or similar to ES but with Search Time ST less than 80% of the ES. Also, it offers more control capability to reduce the search errors. The experimental tests

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Publication Date
Wed Jan 01 2020
Journal Name
2nd International Conference On Materials Engineering &amp; Science (iconmeas 2019)
New application of pervaporation to enhance the conversion of consecutive reaction
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This study investigates consecutive reaction assisted by pervaporation for the first time. It studies the saponification of diethyladipate DA with sodium hydroxide NaOH solution synchronous with separating ethanol from the reaction mixture through an aqueous – organic membrane. The effect of time on some variables such as: permeated ethanol concentration EtOH wt%, separation factor (α), concentration of NaOH solution CB in the reaction medium and the conversion of DA to monoethyladipate (the intermediate product) was studied. It was shown that EtOH wt% and the conversion increased with increasing time unlike CB but (α) showed the existence of maximum value during the time of experiment. The process of reaction assisted by pervaporation

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Publication Date
Mon Mar 01 2021
Journal Name
Journal Of Physics: Conference Series
Synthesis and characterization of some new thiazolidinone derivatives containing indole ring
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Many new heterocyclic compounds including 4-thiazolidinones containing indole with triazole units were described. The new Schiff bases [VII] a, b and [VIII] a, b synthesized by condensation acid hydrazides [II],[VI] with different (aromatic) aldehydes in absolute ethanol. The refluxing equimolar amounts of the Schiff bases ([VII] a, b,[VIII] a, b) with thioglycolic acid in benzene led to get thiazolidin-4-ones derivatives ([IX] a, b and [X] ad). Finally, the new derivatives [XI] ac run out via the reacted compound [IX] a with different n-alkyl bromide (methyl bromide, ethyl bromide, and butyl bromide)

Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
Status Judgment : New Insight into the Promoting Process of Entrepreneurial Behavior
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The present study aims to explore determinants of entrepreneurial behavior from perspective of social theory. It is based on model notions of (Tyler & Blader, 2003) which have focused on studying role of positively personal and social identity in motivating employees to practicing desired behavior which serves the organization in which they work. Based on these notions and previous literature, study model were built. This model explains the relationship between status judgments (perceived internal respect and perceived external prestige)  and entrepreneurial behavior. It includes three main hypotheses. The first and second hypothesis are concerning the relationship between status judgmen

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Publication Date
Fri Jul 01 2011
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
A NEW SPECIES OF RHYNCOMYAROB.-DESVOIDY, 1830 (DIPTERA : CALLIPHORIDAE) FROM IRAQ
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This research includes a detaile description of new species Rhyncomya irakensis sp. nov.
from Iraq.
Localities distribution, host plants and data of collection were recorded.

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