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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
Sat Apr 23 2022
Journal Name
Research Journal Of Pharmacy And Technology
Synthesis, and Antimicrobial Evaluation of New hydrazone Derivatives of (2,4-dinitrophenyl) hydrazine
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In this work, novel compounds of hydrazones derived from (2,4-dinitrophenyl) hydrazine were synthesized. Benzamides derivatives and sulfonamides derivatives were prepared from p-amino benzaldehyde. Then these compounds were condensed with (2,4-dinitrophenyl) hydrazine through Imine bond formation to give hydrazones compounds. The compounds were characterized using FT-IR (IR Affinity-1) spectrometer, and 1HNMR analyses. The majority of the compounds have a moderate antimicrobial activity against “Gram-positive bacteria staphylococcus Aureus, and staphylococcus epidermidis, Gram-negative bacteria Escherichia coli, and Klebsiella pneumoniae, and fungi species Candida albicans” using concentrations of 250 µg\ml.

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Publication Date
Sat Aug 01 2015
Journal Name
Modern Applied Science
A New Method for Detecting Cerebral Tissues Abnormality in Magnetic Resonance Images
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We propose a new method for detecting the abnormality in cerebral tissues present within Magnetic Resonance Images (MRI). Present classifier is comprised of cerebral tissue extraction, image division into angular and distance span vectors, acquirement of four features for each portion and classification to ascertain the abnormality location. The threshold value and region of interest are discerned using operator input and Otsu algorithm. Novel brain slices image division is introduced via angular and distance span vectors of sizes 24˚ with 15 pixels. Rotation invariance of the angular span vector is determined. An automatic image categorization into normal and abnormal brain tissues is performed using Support Vector Machine (SVM). St

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Publication Date
Sun Jul 01 2012
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
NEW RECORD OF PREDATOR MELANTHRIPS PALLIDIOR PRIESNER (THYSANOPTERA: MELANTHRIPIDAE) IN BAGHDAD - IRAQ
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The predator Melanthrips pallidior Priesner regarded as a new record in Baghdad. The specimens were collected from alfalfa field during April 2010 to April 2011 in Abu-Gharib. Morphological characters of different body parts were studied and compared with other specimens by using taxonomic keys.

 

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Publication Date
Wed Nov 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Two New Records of Cerceris Latreille, 1802 (Hymenoptera: Apoidea: Crabronidae) from Iraq
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Abstract<p>In a survey of the crabronid fauna of Iraq during June to October 2022; 9species belonging to the genus <italic>Cerceris</italic> Latreille, 1802 were identified. Twospecies are new record of the fauna of Iraq: <italic>C. dorsalis</italic> Eversmann, 1849 and <italic>C. priesneri</italic> Mochi, 1939. Brief description, diagnostic characters, some collecting information, and photographs of each species are provided. As well provides a key to the species depending on many morphological features especially: propodeal enclosure, semicircular plate at base of second gastral sternites and free margin of clypeus. Moreover, this study observed that most collecte</p> ... Show More
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Publication Date
Sun Jul 01 2012
Journal Name
Applied Soft Computing
A new evolutionary based routing protocol for clustered heterogeneous wireless sensor networks
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Publication Date
Mon Mar 11 2019
Journal Name
Baghdad Science Journal
Synthesis and Antimicrobial Schreening of New 4,5,6,7-Tatra Hydro Benzo Thiophene Derivatives
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A group of derivatives for compounds 2-Amino-3-carboxy-4,5,6,7-tetra hydrobenz -othiophene bearing different heterocyclic moieties such as Schiff bases. B-Lactum, 4-thiazolidinone.1,3-oxazepan. The newly synthesized derivatives have been supported by spectral data FT-IR, H1-NMR. All the synthesized compounds were screened for their antimicrobial activities against gram-positive and gram-negative bacteria as reference.

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Publication Date
Wed Aug 21 2019
Journal Name
Journal Of Global Pharma Technology
Synthesis and characterization of new heterocyclic compounds and studying the biological activity
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Publication Date
Sun Dec 01 2002
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DESCRIPTION OF A NEW SPECIES OF LEUCOSTOMA MEIGEN (DIPTERA: TACHINIDAE) FROM IRAQ
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This work includes a detailed description of the Leucostoma nigricorpuris sp. nov. from
Iraq. Locality, host plants and data of collection were given.

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Publication Date
Wed Dec 30 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Synthesis, Characterization and Preliminary Anti-inflammatory Evaluation of New Fenoprofen Hydrazone Derivatives
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New hydrazone derivatives of Fenoprofen were synthesized and evaluated for their anti-inflammatory activity by means of egg white induced paw edema method. All the synthesized target compounds were characterized by FT-IR spectroscopy, 1HNMR analysis and by measure of their physical properties. The synthesis of the target compounds(H1-H4) was accomplished by multistep reaction procedures. The synthesized target compounds were show activity in reducing paw edema thickness and their anti-inflammatory effect was comparable to that of the standard (Fenoprofen) except for compound H3 which show anti-inflammatory activity higher than Fenoprofen.

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Publication Date
Fri Jan 01 2021
Journal Name
Computers, Materials &amp; Continua
A New Hybrid Feature Selection Method Using T-test and Fitness Function
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