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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
Tue Dec 29 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Synthesis, Characterization, and Antibacterial Evaluation of New Vanillic Acid Derivatives
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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)
NEW RECORDS OF SOME MITE SPECIES INHABITING SOIL IN BAGHDAD
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The soil acari fauna of Citrus orchards of Baghdad in Jadiriya area was studied in a total
of forty-eight samples. Twenty-two species were recorded during the present study of which
eight species were first records to Iraq. The ordinal composition of the soil acari fauna was
predominantly Mesostigmata.
This fauna represents diverse trophic groups. The most abundant groups were the
predacious and the Microphytophagus, while the less abundant groups were the predacious/
Microphytophagus, Macrophytophagus, and Panaphytophagus. The most abundant and
frequent species were Rhizoglyphus sp. Tyrophagus putrescentiea (Scrank), Pachylaelaps
longisetis Halbt. and Stratiolaelaps miles Berl.

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Publication Date
Fri Aug 21 2026
Journal Name
Zootaxa
Two species of spheciform wasps (Hymenoptera: Crabronidae) new to Iraq
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Oxybelochardus mucrosis sp. nov. is described from Iraq, and Palarus funerarius F. Morawitz, 1889 (both Hymenoptera, Crabronidae, Crabroninae) first recorded form that country. The new species can be recognized by its unique mucro, which is elongate semi-triangular, bilobed apically; metanotal squama undivided and curved inward, and setaceous hind tibia.

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Publication Date
Tue Feb 20 2024
Journal Name
Baghdad Science Journal
A New Strategy to Modify Hopfield by Using XOR Operation
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The Hopfield network is one of the easiest types, and its architecture is such that each neuron in the network connects to the other, thus called a fully connected neural network. In addition, this type is considered auto-associative memory, because the network returns the pattern immediately upon recognition, this network has many limitations, including memory capacity, discrepancy, orthogonally between patterns, weight symmetry, and local minimum. This paper proposes a new strategy for designing Hopfield based on XOR operation; A new strategy is proposed to solve these limitations by suggesting a new algorithm in the Hopfield network design, this strategy will increase the performance of Hopfield by modifying the architecture of t

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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)
TWO NEW RECORDS OF THE GENUS APHODIUS ILLIGE, 1798 (COLEOPTERA: APHODIIDAE) IN IRAQTWO NEW RECORDS OF THE GENUS APHODIUS ILLIGE, 1798 (COLEOPTERA: APHODIIDAE) IN IRAQ
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    In this study, the dung beetles Aphodius (Bodilus) ictericus (Laicharting, 1781) and Aphodius (Planolinellus) vittatus Say, 1825 which belongs to the family of Aphodiidae (Order: Coleoptera) are redscribed here as to being found for the first time in Iraq.

 

    The specimens were collected from different regions in the middle of Iraq; the main diagnostic characters and some morphological features of males were drawn and pictured.

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Publication Date
Sun Jan 01 2023
Journal Name
Journal Of Medicinal And Chemical Sciences
Synthesis, Characterization and Thermal Study of Some New Metal Ions Complexes with a New Azo 2-((2-(1H-Indol-2- yl)ethyl)diazinyl)-5-aminophenol
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This research includes the preparation of a new azo 2-((2-(1H-indol-2- yl)ethyl)diazinyl)-5-aminophenol, in which the diazonium salt of 2(1H– Indole–3yl)- ethylamine reacts with a compound 3-aminophenol, and complexes have been prepared with the ions of Ni (II), Pd(II), Pt(IV), and Au(III). The characteristics of compounds include F.A.A, (C. H .N and O), 1H & 13C-NMR, IR, LC-Mass , UV-Vis spectral, DSC/TGA curve, the measurements of magnetic, and molar conductance. Each complex has an amount of [1:1] [M:L] and does not contain electrolytes. Based on the obtained results, molecular structural and geometry have been octahedral geometry suggest of Pt(IV) complex and tetrahedral of Ni (II)complex, the square planar of both Pd(II) and Au(III

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Publication Date
Mon Jan 01 2024
Journal Name
Computers, Materials & Continua
Improving Video Watermarking through Galois Field <i>GF</i>(2<sup>4</sup>) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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Publication Date
Thu Jul 01 2021
Journal Name
University Of Northampton Pue
Validating a Proposed Data Mining Approach (SLDM) for Motion Wearable Sensors to Detect the Early Signs of Lameness in Sheep
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Publication Date
Wed Nov 30 2022
Journal Name
Iraqi Geological Journal
A Predictive Model for Estimating Unconfined Compressive Strength from Petrophysical Properties in the Buzurgan Oilfield, Khasib Formation, Using Log Data
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Unconfined compressive strength (UCS) of rock is the most critical geomechanical property widely used as input parameters for designing fractures, analyzing wellbore stability, drilling programming and carrying out various petroleum engineering projects. The USC regulates rock deformation by measuring its strength and load-bearing capacity. The determination of UCS in the laboratory is a time-consuming and costly process. The current study aims to develop empirical equations to predict UCS using regression analysis by JMP software for the Khasib Formation in the Buzurgan oil fields, in southeastern Iraq using well-log data. The proposed equation accuracy was tested using the coefficient of determination (R²), the average absolute

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Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Comparing Bayesian methods to estimate the failure probability for electronic systems in case the life time data are not available
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In this research, we find the Bayesian formulas and the estimation of Bayesian expectation for product system of Atlas Company.  The units of the system have been examined by helping the technical staff at the company and by providing a real data the company which manufacturer the system.  This real data include the failed units for each drawn sample, which represents the total number of the manufacturer units by the company system.  We calculate the range for each estimator by using the Maximum Likelihood estimator.  We obtain that the expectation-Bayesian estimation is better than the Bayesian estimator of the different partially samples which were drawn from the product system after  it checked by the

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