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Comparison of Prediction Programs for Short Wave Circuit Link from Iraq to Test points on Both Earth Hemispheres during Solar Minimum
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This paper compare  the accurecy of HF propagation  prediction programs for  HF circuits links between Iraq and  different points world wide  during August 2018 when  solar cycle 24 (start 2009 end 2020) is at minimun activity and also find out the best communication mode  used. The prediction   programs like Voice of America Coverage Analysis Program (VOACAP) and ITU Recommendation RS 533 (REC533 )  had been used to generat HF circuit link  parameters like Maximum Usable Frequency ( MUF) and Frequency of Transsmision (FOT) .Depending  on the predicted parameters (data)  , real radio contacts had been done using a radio transceiver from Icom  model IC 7100 with 100W RF power, tuner box and homemade  dipole antenna of 10 m length and  8m height above ground. From  correlation between the predicted data and observed data  the result was not accurate .

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Publication Date
Thu Sep 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Some Methods for Estimating Mixture of Linear Regression Models with Application
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 A mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the others

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Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
CdSe/CdS core/shell in polyacrylamide polymer matrix for Quantumdots Luminescent solar concentrator
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Luminescent solar concentrator (LSC) are used to enhance       photoresponsivity of solar cell. The Quantumdots luminescent solar concentrator (QDLSC) consists of CdSe/CdS core/shell nanoparticles embedded in polyacrylamide polymer matrix positioned on the top surface of the silicon solar cell. This procedure improves the conversion efficiency of the bare silicon solar cell. The conversion efficiency of the solar cell has increased from 7.3% to 10.3%.  this improvement is referred to the widening of the response spectral region window  of the a- Si. Solar cell.

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Publication Date
Thu Oct 15 2015
Journal Name
Al Mustansyriah Journal Of Science
Comparison between (ARIMA) and (ANNs) models for estimating the relative humidity for Baghdad city
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The aim of the research is to study the comparison between (ARIMA) Auto Regressive Integrated Moving Average and(ANNs) Artificial Neural Networks models and to select the best one for prediction the monthly relative humidity values depending upon the standard errors between estimated and observe values . It has been noted that both can be used for estimation and the best on among is (ANNs) as the values (MAE,RMSE, R2) is )0.036816,0.0466,0.91) respectively for the best formula for model (ARIMA) (6,0,2)(6,0,1) whereas the values of estimates relative to model (ANNs) for the best formula (5,5,1) is (0.0109, 0.0139 ,0.991) respectively. so that model (ANNs) is superior than (ARIMA) in a such evaluation.

Publication Date
Sun Sep 07 2008
Journal Name
Baghdad Science Journal
Bioremoval of chromium from wastewater of tannery factory in Iraq
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Bioremoval of chromium from wastewater of tannery factory in Iraq was studied. The bacteria Proteus vulgaris 7E showed an enhanced capability in biosorping chromium when its concentration increased in the solution, reaching a maximum of 476,7 mg/ ml out of 492 mg/ ml under optimum conditions at pH 6 and 50°C at one hour contact time and biomass of 1 mg/ml. The present results showed that dead cells of P. vulgaris 7E biosorbed 87.41 mg/ml of chromium in comparison with91.18 mg/ml of chromium biosorbed by living cells, this indicates the insignificant effect of physiological state of cells. It was found that the above biosorption is physico-chemical process depends upon electrostatic attraction forces. The results has illustrated that the

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Publication Date
Sun Jul 01 1990
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DESCRIPTION OF NEW SPECIES OF TERMITES (INSECTA, ISOPTERA) FROM IRAQ
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Two specie's of terrnitls are described as new to science from Iraq Amitermes corpnlentus sp. n. and Anacanthotermes savvensis sp. n., with two figures.

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Publication Date
Sun Dec 31 2023
Journal Name
Iraqi Geological Journal
Biostratigraphy of Shiranish Formation from Selected Wells, Central of Iraq
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The Quantitative high-resolution planktonic foraminiferal analysis of the subsurface section in three selected wells in the Ajeel Oil Field (Aj-8, Aj-12, and Aj-15) in Tikrit Governorate, Central Iraq has revealed that Shiranish Formation deposited in Late Campanian- Latest Maastrichtian age. This formation consists mainly of marly and marly limestone yielding diverse planktonic foraminiferal assemblages and calcareous benthic foraminifera, with a total of 46 species that belong to 23 genera, Three zones and four subzones, which cover the Late Campanian to the Latest Maastrichtian, were identified based on the recorded planktonic foraminifera and their ranges. They are as follows:1. Globotruncana aegyptiaca Zone that dated to be Lat

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Publication Date
Fri Dec 12 2003
Journal Name
Iraqi Journal Of Laser
The Influence of Short Wavelength Laser on the Pupae Development of the Old World Screw- Worm Fly (OWSWF) Chrysomya bezziana Villeneuve (Diptera: Calliphoridae)
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The biological effects of pulsed N2-laser on the old world screw-worm fly, Chrysomya bezziana Villeneuve in the pupal stage were investigated. Different laser parameters were involved in this work. The old pupae of 1, 2, 3, 4 and 5 days were exposed to laser radiation during 10, 30 and 60 second with repetition rate 10, 20 and 30 pulse/second. The percent of normal adults emergence (female and male) was investigated. The results showed that the adults emergence was highly decreased as the repetition rate and exposure time increased when the pupae irradiated for 1, 2 and 3 days old as compared with 4 and 5 days. The results also indicated that the pupal period was significantly increased of irradiated pupae for 1, 2, 3 and 4 days old, whi

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Publication Date
Wed Feb 22 2023
Journal Name
Iraqi Journal Of Science
The Effect of Short Range Correlation on The Nuclear Charge Density Distribution, Elastic and Inelastic Electron Scattering Coulomb Form Factors of 18O Nucleus
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The effect of short range correlations on the inelastic longitudinal Coulomb form
factors for the lowest four excited 2+ states in 18O is analyzed. This effect (which
depends on the correlation parameter β) is inserted into the ground state charge
density distribution through the Jastrow type correlation function. The single particle
harmonic oscillator wave function is used with an oscillator size parameter b. The
parameters β and b are, considered as free parameters, adjusted for each excited state
separately so as to reproduce the experimental root mean square charge radius of
18O. The model space of 18O does not contribute to the transition charge density. As
a result, the inelastic Coulomb form factor of 18

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Publication Date
Thu Jun 01 2023
Journal Name
Iaes International Journal Of Artificial Intelligence (ij-ai)
Evaluation of massive multiple-input multiple-output communication performance under a proposed improved minimum mean squared error precoding
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<span lang="EN-US">The fundamental of a downlink massive multiple-input multiple-output (MIMO) energy- issue efficiency strategy is known as minimum mean squared error (MMSE) implementation degrades the performance of a downlink massive MIMO energy-efficiency scheme, so some improvements are adding for this precoding scheme to improve its workthat is called our proposal solution as a proposed improved MMSE precoder (PIMP). The energy efficiency (EE) study has also taken into mind drastically lowering radiated power while maintaining high throughput and minimizing interference issues. We further find the tradeoff between spectral efficiency (SE) and EE although they coincide at the beginning but later their interests become con

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Publication Date
Thu Jun 01 2023
Journal Name
International Journal Of Artificial Intelligence (ij-ai)
Evaluation of massive multiple-input multiple-output communication performance under a proposed improved minimum mean squared error precoding
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<span lang="EN-US">The fundamental of a downlink massive multiple-input multiple-output (MIMO) energy- issue efficiency strategy is known as minimum mean squared error (MMSE) implementation degrades the performance of a downlink massive MIMO energy-efficiency scheme, so some improvements are adding for this precoding scheme to improve its workthat is called our proposal solution as a proposed improved MMSE precoder (PIMP). The energy efficiency (EE) study has also taken into mind drastically lowering radiated power while maintaining high throughput and minimizing interference issues. We further find the tradeoff between spectral efficiency (SE) and EE although they coincide at the beginning but later their interests become con

... Show More
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