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The compound stream event of March 20-25, 2011 as measured by the STEREO B spacecraft
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Abstract<p>The interaction of interplanetary coronal mass ejections (ICME) with each other and with co-rotating interaction regions (CIR) changes their configuration, dynamics, magnetic field and plasma characteristics and can make space weather forecasting difficult. During the period of March 20–25, 2011, the Solar Terrestrial Relation Observatory (<italic>STEREO</italic> B) encountered a compound stream containing several interacting structures. Our analysis suggests that the stream consists of two ICMEs followed by an embedded ICME/CIR. The sudden appearance of the third ICME within the fast wind side of the CIR causes the proton temperature(<inline-formula><alternatives><tex-math>$T_{p} $</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><msub><mi>T</mi><mi>p</mi></msub></math></alternatives></inline-formula>) to drop suddenly to its lowest level in about 1.2 hours, from <inline-formula><alternatives><tex-math>$3.89 \times 10^{5}$</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mn>3.89</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>5</mn></mrow></msup></math></alternatives></inline-formula> K to <inline-formula><alternatives><tex-math>$1.07 \times 10^{4}$</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mn>1.07</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>4</mn></mrow></msup></math></alternatives></inline-formula> K (by a factor of ≈36). The fast wind which follows the CIR influences not only the third ICME’s temperature but also its proton beta (<inline-formula><alternatives><tex-math>$\upbeta_{\mathrm{p}}$</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><msub><mi>β</mi><mi>p</mi></msub></math></alternatives></inline-formula>). In addition, the third ICME impacts the CIR through expansion and deceleration. A forward pressure wave penetrates ICME1. It’s source is either the second ICME, the merged third ICME and CIR, or it may be a remnant shock. The compression causes an increase of the <inline-formula><alternatives><tex-math>$T_{p}$</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><msub><mi>T</mi><mi>p</mi></msub></math></alternatives></inline-formula> and <inline-formula><alternatives><tex-math>$\upbeta_{\mathrm{p}}$</tex-math><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><msub><mi>β</mi><mi>p</mi></msub></math></alternatives></inline-formula> of the second and part of the first ICME. Despite the signatures of four large-scale interacting structures within the compound stream, it is difficult to reconcile the <italic>in-situ</italic> sequence with other remote sensing observations of ejecta close to the Sun because of the large system of coronal expanding loops above the active region. Compound streams therefore remain difficult to interpret, and further understanding of the subject will depend on the future study of similar events.</p>
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Publication Date
Mon Feb 13 2023
Journal Name
Journal Of Educational And Psychological Researches
The Degree of Practicing Citizenship Values by Bisha University Students
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Abstract

 

The study aims to identify the degree of citizenship values practiced by Bisha University students and identify the impact of gender, college, and academic level, on the degree of the practice of University students for citizenship values. The researcher used the descriptive-analytical method including a questionnaire of (44) items. To process the data, the researcher applied the computational averages, standard deviations, percentages, and T-test. The questionnaire was implemented on a sample of (600) of the 2 and 8 levels during the second semester of the academic year (2020-2019) at Bisha University. The study findings revealed that the degree of the pra

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Publication Date
Sat Mar 30 2013
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Studying the Performance of Refrigeration Units Powered by Solar Panel
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An experimental study was conducted to determine the performance of a solar electric refrigeration system. The system contained flat photovoltaic solar panel which absorbs the solar energy and convert it to electrical energy, used to run the refrigeration cycle. Two refrigeration cycles with electrical solar panel were used over a period of 12 months, the first one with classical parts known in refrigeration cycle, while the second one introduced heat exchanger which improves the coefficient of performance by saving the consumed energy. The coefficient of performance of these refrigeration cycles with compressor efficiency 85% are 2.102 and 2.57 respectively. The overall efficiency of the two systems are 18.9% and 23.13%.

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Publication Date
Sun Jul 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The Use of Discourse Markers by Iraqi Secondary Schools Pupils
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This research aims at investigating pupils’ ability in using discourse markers which are identified in the English textbooks of secondary schools. Four texts are chosen from third intermediate class. The four texts are short stories of different topics.                                                  

        This research hypothesizes that there are no statistical significant differences among Iraqi intermediate pupils’ ability in using textual

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Publication Date
Thu Mar 01 2007
Journal Name
Al-khwarizmi Engineering Journal
The Inverse Solution Of Dexterous Robot By Using Neural Networks
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The inverse kinematics of redundant manipulators has infinite solutions by using conventional methods, so that, this work presents applicability of intelligent tool (artificial neural network ANN) for finding one desired solution from these solutions. The inverse analysis and trajectory planning of a three link redundant planar robot have been studied in this work using a proposed dual neural networks model (DNNM), which shows a predictable time decreasing in the training session. The effect of the number of the training sets on the DNNM output and the number of NN layers have been studied. Several trajectories have been implemented using point to point trajectory planning algorithm with DNNM and the result shows good accuracy of the end

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Publication Date
Fri Apr 05 2013
Journal Name
Journal Of Intelligent Material Systems And Structures
Increasing the power of piezoelectric energy harvesters by magnetic stiffening
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A piezoelectric cantilever beam with a tip mass at its free end is a common energy harvester configuration. This article introduces a new principle of designing such a harvester that increases the generated power without changing the resonance frequency of the harvester: the attraction force between two permanent magnets is used to add stiffness to the system. This magnetic stiffening counters the effect of the tip mass on the efficient operation frequency. Five set-ups incorporating piezoelectric bimorph cantilevers of the same type in different mechanical configurations are compared theoretically and experimentally to investigate the feasibility of this principle: theoretical and experimental results show that magnetically stiffened harve

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Publication Date
Sun Dec 01 2024
Journal Name
Anbar Journal Of Agricultural Sciences
IMPROVING THE QUALITY OF POTATO MINI TUBERS BY SUSTAINABLE CULTIVATION
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Publication Date
Tue Jan 01 2019
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees19gr
The use of cold atmospheric plasma in pentostam enhancement as Leishmaniasis treatment in vitro
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This study illustrates in vitro effect of cold atmospheric plasma (CAP) on the treatment of Leishmania. In addition, the study evaluated the effect of drug treatment (pentostam) and the combination treatment of pentostan and CAP at different doses and incubation time 24 h in order to assess the most effective treatment. The duration of the cold plasma doses was 1 min, 2 min and 3 min, while the pentostam doses were 2.5 µg/ml and 5 µg/ml. The combinations therapies included combining the three cold plasma doses with the pentostam doses to test 6 combinations of treated in vitro. The maximum growth inhibition was given by combination treated 46% and 44% for donovani and tropica leishamnia respectively; these results give an indi

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
The Combined Action of Zeolite and Chlorinated Rubber as Flame Retardants for Epoxy Resin
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In this work , the effect of chlorinated rubber (additive I), zeolite 3A with chlorinated rubber (additive II), zeolite 4A with chlorinated rubber (additiveIII), and zeolite 5A with chlorinated rubber (additive IV), on flammability for epoxy resin studied, in the weight ratios of (2, 4, 7,10 & 12%) by preparing films of (130x130x3) mm in diameters, three standard test methods used to measure the flame retardation which are ; ASTM : D-2863 , ASTM : D-635 & ASTM : D-3014. Results obtained from these tests indicated that all of them are effective and the additive IV has the highest efficiency as a flame retardant.

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Publication Date
Sun Dec 10 2017
Journal Name
Current Research In Microbiology And Biotechnology
the Efficiency of Dettol as Detergent against Microbial Biofilm formation isolated from UTI infections‏
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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Co-digestion of Shumblan with Different Wastes as a Source for the Biogas Production
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Shumblan (SH) is one of the most undesirable aquatic plants widespread in the irrigation channels and water bodies. This work focuses on boosting the biogas potential of shumblan by co-digesting it with other types of wastes without employing any chemical or thermal pretreatments as done in previous studies. A maximum biogas recovery of 378 ml/g VS was reached using shumblan with cow manure as inoculum in a ratio of 1:1. The methane content of the biogas was 55%. Based on volatile solid (VS) and C/N ratios, biogas productions of 518, 434, and 580 ml/g VS were obtained when the shumblan was co-digested with food wastes (SH:F), paper wastes (SH:P), and green wastes (SH:G) respectively. No significant changes of methane contents were observ

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