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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
Wed Dec 01 2021
Journal Name
Baghdad Science Journal
New Spectral Range Generations from Laser-plasma Interaction
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            High-intensity laser-produced plasma has been extensively investigated in many studies. In this demonstration, a new spectral range was observed in the resulted spectra from the laser-plasma interaction, which opens up new discussions for new light source generation. Moreover, the characterizations of plasma have been improved through the interaction process of laser-plasma. Three types of laser were incorporated in the measurements, continuous-wave CW He-Ne laser, CW diode green laser, pulse Nd: YAG laser. As the plasma system, DC glow discharge plasma under the vacuum chamber was considered in this research. The plasma spectral peaks were evaluated, where they refer to Nitrogen gas. The results indicated that the

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Publication Date
Tue May 12 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis and Biological Activity of New Imidazaldinone Derivatives
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A research include of synthesized five member ring, which has been synthesized by condensation of 2-(1-(4- hydroxyphenyl) ethylidene)hydrazine-1-carbothioamide[I] with α-chloro ethylacetate in sodium acetate (fused) to form ethyl 2-(4-(1-((4-oxo-2-thioxopyrrolidin-3-ylidene)hydrazono) ethyl)phenoxy)acetate [II]. After that reacted [II]with hydrazine hydrate to resulting compound [III]. Compound [III] was refluxed with 4-aminobenzoicacid in excess of phosphorus oxy chloride give compound [IV],the later compound [IV] interact with acetyl acetone or ethylacetoacetate give to pyrazole and pyrazoline derivatives[V],[VI]. While when reacted with different aromatic aldehydes and one ketone consistence Schiff base derivatives [VII]a-e . The FTIR a

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Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
Harmonic Knife New Haemostatic Procedure In Thyroid Surgery
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Background: Thyroid operation needs very meticulous haemostasis to have minimal morbidity and mortality.

Objectives: Assessment of harmonic knife in open thyroid surgery as anew haemostatic procedure .

Type of the study: Cross-sectional study.

Methods: This study had been conducted at Alkindy teaching hospital in Baghdad city from the 1st of May 2013 to the 1st of January 2017  on 229  goiterous patients who needs thyroidectomy(36 males,193 females),divided in 2 groups according to the haemostatic procedure used during their operations, Group A (15 males,85females)using the usual conventional surgery(

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Religious differences for customers And New Products Adopation
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Abstract

The problem with the search at the reduction of adoption of new products, as there are three hypotheses of research have been formulated , the first one is no significant correlation between the religious and differences to customers and adopt new products, and This Study Aimed To Investigate The Relationship Between Religious differences for customers And New Products Adoption, Applied On Arab Mall Commercial Customers/ Egypt, an Analytical Model Is Developed As Guideline To Test The The Relationship Between Religious differences for customers And New Products Adoption, Aquantative Method With Deductive Approach Were Chosen In This Research . In Order To Collect Primary Data, A questionnaire Is

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Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
On New Weibull Inverse Lomax Distribution with Applications
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In this paper, simulation studies and applications of the New Weibull-Inverse Lomax (NWIL) distribution were presented. In the simulation studies, different sample sizes ranging from 30, 50, 100, 200, 300, to 500 were considered. Also, 1,000 replications were considered for the experiment. NWIL is a fat tail distribution. Higher moments are not easily derived except with some approximations. However, the estimates have higher precisions with low variances. Finally, the usefulness of the NWIL distribution was illustrated by fitting two data  sets

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Publication Date
Thu Mar 01 2012
Journal Name
International Journal Of Innovative Computing, Information And Control
ITTP: A new transport protocol for VoIP applications
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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
new Estimator of the parameter of negative exponential
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the main of this paper is to give a comprehensive presentation of estimating methods namely maximum likelihood bayes and proposed methods for the parameter

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Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Pharmaceutical Sciences And Research
synthesis new hetrocyiclic compound derived from fouroic acid
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Publication Date
Thu Jun 15 2023
Journal Name
Bionatura
New record species of Gypsophila L. in Iraq
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G. tuberculosa is a newly recorded species from the Caryophyllaceae family for Iraqi flora, collected from the Arbil district from May to August. Morphological descriptions with macro and micro features illustrated with plates and dimensions, the species is related to G. pallida and distinguished from calyx properties, especially the presence of large prominent druses crystals. Keywords: Caryophyllaceae, Gypsophila, Iraq, New record, pallida.

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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Some New Morpholine Derivatives
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In this paper a new series of morpholine derivatives was prepared by reacting the morpholine with ethyl chloro acetate in the presence triethylamine as a catalyst in benzene gave morpholin-N-ethyl acetate(1) which reacted with hydrazine hydrate in ethanol, and gave morpholin-N-ethyl acetohydrazide (2) . Morpholin-N-aceto semithiocarbazide (3) were prepared by reacting compound(2) with ammonium thiocyanate , concentrated hydrochloric acid and ethanol as a solvent .Compound (3) reacted with sodium hydroxide and hydrochloric acid to give 5-(morpholin-N-methylene)-1H-1,2,4-triazole-3-thiol (4) .The new series of 1,2,4-triazol derivatives (5-8) was synthesized by reaction of compound(4) with formaldehyde , DMF as a solvent and different

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