2,106 research outputs found

    Electron acceleration by cascading reconnection in the solar corona I Magnetic gradient and curvature effects

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    Aims: We investigate the electron acceleration in convective electric fields of cascading magnetic reconnection in a flaring solar corona and show the resulting hard X-ray (HXR) radiation spectra caused by Bremsstrahlung for the coronal source. Methods: We perform test particle calculation of electron motions in the framework of a guiding center approximation. The electromagnetic fields and their derivatives along electron trajectories are obtained by linearly interpolating the results of high-resolution adaptive mesh refinement (AMR) MHD simulations of cascading magnetic reconnection. Hard X-ray (HXR) spectra are calculated using an optically thin Bremsstrahlung model. Results: Magnetic gradients and curvatures in cascading reconnection current sheet accelerate electrons: trapped in magnetic islands, precipitating to the chromosphere and ejected into the interplanetary space. The final location of an electron is determined by its initial position, pitch angle and velocity. These initial conditions also influence electron acceleration efficiency. Most of electrons have enhanced perpendicular energy. Trapped electrons are considered to cause the observed bright spots along coronal mass ejection CME-trailing current sheets as well as the flare loop-top HXR emissions.Comment: submitted to A&

    Rate Me: Risk Assessment Drones and the Resurrection of Discriminatory Insurance Practices

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    Miről mesélnek a kora újkori középiskolai adatsorok? : a kassai jezsuita gimnázium anyakönyvének elektronikus feldolgozása - egy kutatási projekt első eredményei = The electronical processing of the school register of the Jesuit Grammar School in Košice - the first results of a research project

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    In spite of the fact that the Society of Jesus had a quasi-monopoly position in Catholic ecclesiastical secondary education in the Kingdom of Hungary and Transylvania in the 17th and 18th centuries, until recently, registers of Jesuit grammar schools have not been utilised sufficiently. As referred to in the title, the study examines the possibilities of the electronical processing of the school register of the early modern Jesuit Grammar School in Kassa (Košice, present-day: Slovakia), introducing the first results. The project has started within the confines of the subproject of the “MTA–ELTE History of Universities Research Group” as a continuation of the project called “Catholic Schooling in Hungary in the Early Modern Period: the Students of the Győr, Nagyszombat and Pozsony Jesuit Colleges”. As results of the latter project, the school registers of the Jesuit grammar schools in Győr, Pozsony (Bratislava, present-day: Slovakia) and Nagyszombat (Trnava, present-day: Slovakia) had been already processed electronically and student databases had been created, which are currently available at the Hungaricana – Hungarian Cultural Heritage Portal. The importance of these student databases, including the Kassa one, lies primarily in the potential of complex queries. Statistical data series can be produced by using of them from an essentially pre-statistical period, which could provide a sharper insight into a well-defined broad segment of society of the early modern Kingdom of Hungary. Moreover, cohort analyses based on them could contribute to revealing school studies and educational paths, providing opportunities to make inductive reasonings. Nevertheless, especially combined with other databases, hopefully those will be also useful for researchers dealing with information history, because they aid to draw higher-order conclusions through the various logical queries

    Optimális éves viselkedési modellek: út a fiziológiától a populációkig? = Optimal annual routines: a path from physiology to populations?

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    A pályázat fő célja annak kiderítése volt, hogy a különböző állapotváltozók hogyan befolyásolják az optimális viselkedést, speciálisan a hogyan befolyásolják a fő életmenet események időzítését az éves cikluson belül. E cél elérése érdekében több modellt fejlesztettünk, és változatos terepi megfigyeléseket és aviáriumi kísérleteket folytattunk. Fő modelljeink azt mutatják, hogy az állapotváltozók (pl. tollminőség, energiatartalékok) jelentősen befolyásolhatják a vedlés és vándorlás időzítését, de a táplálékforrás időbeli eloszlása és szezonalitása is jelentős hatással lehet. Fő empirikus eredményeink szerint a táplálék minősége és a paraziták fertőzése jelentősen befolyásolhatja a tollminőséget. Egy komparatív vizsgálatban kimutattuk, hogy a vándorlás időzítését a különféle életmenet jellemzők jelentősen befolyásolják, de a szexuálisan szelektált jellegeknek nincs ilyen hatása. | The main aim of the project was to investigate how state variables effect optimal behaviour in general, and the optimal timing of major life history events over the annual cycle, in particular. To accomplish this aim we developed a couple of annual routine models and performed various field observations and aviary experiments. Our main models show that state variables (quality of feathers, energy reserves) can significantly influence the timing of optimal behaviour (moult, migration) but they also underline the importance of the temporal distribution and seasonality of food sources. Our main empirical results show that diet quality and parasite infection influence feather quality considerably. By a comparative study we found that life history traits (e.g. migration distance and diet) but not sexually selected traits influence the timing of migration

    Optimális vedlési stratégiák = Optimal moult strategies

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    A pályázat fő célja annak kiderítése volt, hogy a különböző állapotváltozók hogyan befolyásolják az optimális viselkedést, speciálisan a hogyan befolyásolják a fő életmenet események időzítését az éves cikluson belül. E cél elérése érdekében több modellt fejlesztettünk, és változatos terepi megfigyeléseket és aviáriumi kísérleteket folytattunk. Fő modelljeink azt mutatják, hogy az állapotváltozók (pl. tollminőség, energiatartalékok) jelentősen befolyásolhatják a vedlés és vándorlás időzítését, de a táplálékforrás időbeli eloszlása és szezonalitása is jelentős hatással lehet. Fő empirikus eredményeink szerint a táplálék minősége és a paraziták fertőzése jelentősen befolyásolhatja a tollminőséget. Egy komparatív vizsgálatban kimutattuk, hogy a vándorlás időzítését a különféle életmenet jellemzők jelentősen befolyásolják, de a szezuálisan szelektált jellegeknek nincs ilyen hatása. | The main aim of the project was to investigate how state variables effect optimal behaviour in general, and the optimal timing of major life history events over the annual cycle, in particular. To accomplish this aim we developed a couple of annual routine models and performed various field observations and aviary experiments. Our main models show that state variables (quality of feathers, energy reserves) can significantly influence the timing of optimal behaviour (moult, migration) but they also underline the importance of the temporal distribution and seasonality of food sources. Our main empirical results show that diet quality and parasite infection influence feather quality considerably. By a comparative study we found that life history traits (e.g. migration distance and diet) but not sexually selected traits influence the timing of migration

    Analysis of weld joints made of titanium alloy GRADE 2 produced by electron beam welding

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    Selected properties of welded joints of 2 mm thick titanium alloy Grade 2 produced by different welding parameters of electron beam welding were investigated. The visual inspection, macro and micro analysis, tensile strength test and microhardness measurements were performed. Samples manufactured by appropriate welding parameters had no internal defects, heat-affected zone (HAZ) was narrow and transformation from α phase to β phase was observed in this area. The failure occurred in the base metal during tensile test, while maximum ultimate tensile strength reached 454,3 MPa

    A study of the grass tetany syndrome in Ohio

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    Evaluation of an online fermentation monitoring system

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    The need to introduce promising bioethanol production technologies calls for advanced laboratory techniques to study experiment designs and to obtain their results in a quick and reliable way. Real time monitoring based on general principles of ethanol fermentation, such as effluent CO2 volume, avoids time consuming steps, long lasting analyses and delivers information about the process directly. A device based on the above features and capable for real time monitoring on parallel channels was developed by the authors and is described in this paper. Both for calibration and for fermentation, test runs were carried out on different days and channels. Statistical evaluation was based on the obtained data. According to the t-test (P=0.05) and Grubbs analysis, the calibration method is reliable regardless of the date of calibration. When evaluating the fermentation results by ANCOVA acceptable standard derivations were obtained as impact of channel (58.8 ml), date (82.1 ml) and incorporating all impacts (116.2 ml). The final ethanol concentrations calculated based on the gas volume were compared to ones determined by HPLC and an average difference of 10% was found. Thus, the device proved to be advantageous in monitoring fermentation
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