1,325 research outputs found

    A Trigger Interface Board to manage trigger and timing signals in CTA Large-Sized Telescope and Medium-Sized Telescope cameras

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    One of the main goals of the Cherenkov Telescope Array (CTA) observatory is to improve the Îł\gamma-ray detection sensitivity by an order of magnitude, compared to the current ground-based observatories. Widening the energy coverage down to 20 GeV and up to 300 TeV is also an important goal. This goal will be possible by using Large-Sized Telescopes (LSTs) for the energy range of 20--200 GeV, Medium-Sized Telescopes (MSTs) for 100 GeV--10 TeV, and Small-Sized Telescopes (SSTs) for energies above 5 TeV. The LSTs, which focus on the lowest energies, are operated in a region dominated by background events originated from the night sky background. To reduce such background events as much as possible, the LST cameras are only read out if at least two of them have been triggered in a short-time coincidence window. Such trigger is implemented for each LST camera in a dedicated module called Trigger Interface Board (TIB). In addition, the TIB is also used in MSTs equipped with the NectarCAM camera system to manage the different trigger and timing signals between LSTs and MSTs, as well as to monitor the different counting rates and dead-time of the cameras. It also assigns a time stamp to each event, which is recorded along with the information provided by the CTA global timing distribution system, based on the White Rabbit protocol. Therefore, the event arrival time can be determined in a redundant way. In this contribution, the main features and the technical performance of the TIB are presented.Comment: All CTA contributions at arXiv:1709.03483. In Proceedings of the 35th International Cosmic Ray Conference (ICRC2017), Busan, Kore

    Sistema de Seguridad Basado en una Plataforma Heterogénea Distribuida

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    Este trabajo presenta el proyecto “Ecosistema Digital de Seguridad”, realizado en la asignatura Sistemas Empotrados Distribuidos, perteneciente a la titulaciĂłn MĂĄster en IngenierĂ­a InformĂĄtica de la Universidad Complutense de Madrid. En este trabajo se describe e implementa un sistema de seguridad por medio de una plataforma heterogĂ©nea, cuyo objetivo es la verificaciĂłn de los usuarios autorizados. En concreto, la placa Raspberry Pi se encarga del reconocimiento de la imagen y la contraseña, mientras que la STM32F4 Discovery sirve de interfaz con el usuario, recibiendo la contraseña y enviĂĄndosela a la Raspberry a travĂ©s de la interfaz RS-232.This work presents the project en titled “Digital Security Ecosystem”, carried out as a final project in th e Distributed Embedded Systems subject, which belongs to the Computer Engineering Master, at the Complutense University of Madrid. In this work, a security system is described and implemented through a hetero geneous platform, whose objective consists of the authorized users’ verification. Concretely , the Raspberry Pi board is responsible for identifying the image and the password, while the STM32F4 Discovery board acts as the user interface, receivi ng the password which will be sent to the Raspberry by using the RS-232 interface.Universidad de Granada: Departamento de Arquitectura y TecnologĂ­a de Computadores; Vicerrectorado para la GarantĂ­a de la Calidad

    FR2 5G Networks for Industrial Scenarios: An Experimental Characterization and Beam Management Procedures in Operational Conditions

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    Industrial environments constitute a challenge in terms of radio propagation due to the presence of machinery and the mobility of the different agents, especially at mmWave bands. This paper presents an experimental evaluation of a FR2 5G network deployed in an operational factory scenario at 26 GHz. The experimental characterization, performed with autonomous mobile robots that self-navigate the industrial lab, leads to the analysis of the received power along the factory and the evaluation of reference path gain models. The proposed assessment deeply analyzes the physical layer of the communication network under operational conditions. Thus, two different network configurations are assessed by measuring the power received in the entire factory, providing a comparison between deployments. Additionally, beam management procedures, such as beam recovery, beam sweeping or beam switching, are analyzed since they are crucial in environments where mobile agents are involved. They aim for a zero interruption approach based on reliable communications. The results analysis shows that beam recovery procedures can perform a beam switching to an alternative serving beam with power losses of less than 1.6 dB on average. Beam sweeping analysis demonstrates the prevalence of the direct component in Line-of-Sight conditions despite the strong scattering component and large-scale fading in the environment.Comment: 11 pages, 10 figure

    Case studies in physiology: Training adaptation in an elite athlete after breast cancer diagnosis.

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    The aim of this study was to evaluate the capacity to return to competition of a 28-yr-old female 400-m hurdle elite athlete after a diagnosis of breast cancer. The study lasted 14 mo after diagnosis. She was tested four times (T1–T4) to measure body mass (BM), body mass index (BMI), percentage of total fat mass (TFM%), total fat-free mass (TFFM%), bone mineral density (BMD), one-repetition maximum (1RM), and maximal power (MP) in bench press and half squat, maximum oxygen uptake, and 400-m dash and hurdles. T0 (baseline time) was established with values before diagnosis. BM and BMI increased from T0 to T1 (5.3% and 5.2%) and remained stable. BMD experienced no change. TFM% values decreased from T1 to T4 (3.5%). TFFM% values increased from T1 to T3 (0.9%). During T1–T2, the athlete presented a global decline from T0 in 1RMSquat, 1RMBench, MPSquat, and MPBench (32.6%, 27.2%, 37.5%, and 27.6%, respectively). Results during T3–T4 were also lower for these parameters from T0 (23.3%, 20.6%, 23.4%, and 11%). During T1–T2, the V̇o2max declined compared with T0 (1.8% and 6.4%), showing a small increase at T3 (+1%) and reaching the lowest level at T4 (9%). During T1–T2, the time record of 400-m dash (8.3%) and hurdles (7.4%) increased. However, a slight improvement was found at T3 (1.3% and 0.6%, respectively). The results of this case study reflect that exercise training improved body composition, maintained BMD and TFFM, but could not completely reverse the worsening of the cardiorespiratory, muscle strength and power, and running performance levels.pre-print325 K

    TransformEHRs: a flexible methodology for building transparent ETL processes for EHR reuse

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    Background: During the COVID-19 pandemic, several methodologies were designed for obtaining electronic health record (EHR)-derived datasets for research. These processes are often based on black boxes, on which clinical researchers are unaware of how the data were recorded, extracted, and transformed. In order to solve this, it is essential that extract, transform, and load (ETL) processes are based on transparent, homogeneous, and formal methodologies, making them understandable, reproducible, and auditable. Objectives: This study aims to design and implement a methodology, according with FAIR Principles, for building ETL processes (focused on data extraction, selection, and transformation) for EHR reuse in a transparent and flexible manner, applicable to any clinical condition and health care organization. Methods: The proposed methodology comprises four stages: (1) analysis of secondary use models and identification of data operations, based on internationally used clinical repositories, case report forms, and aggregated datasets; (2) modeling and formalization of data operations, through the paradigm of the Detailed Clinical Models; (3) agnostic development of data operations, selecting SQL and R as programming languages; and (4) automation of the ETL instantiation, building a formal configuration file with XML. Results: First, four international projects were analyzed to identify 17 operations, necessary to obtain datasets according to the specifications of these projects from the EHR. With this, each of the data operations was formalized, using the ISO 13606 reference model, specifying the valid data types as arguments, inputs and outputs, and their cardinality. Then, an agnostic catalog of data was developed through data-oriented programming languages previously selected. Finally, an automated ETL instantiation process was built from an ETL configuration file formally defined. Conclusions: This study has provided a transparent and flexible solution to the difficulty of making the processes for obtaining EHR-derived data for secondary use understandable, auditable, and reproducible. Moreover, the abstraction carried out in this study means that any previous EHR reuse methodology can incorporate these results into them.Ministerio de EconomĂ­a y Competitividad Instituto de Salud Carlos III PI18/00981, PI18/01047, PI18CIII/00019.S

    MAGIC very large zenith angle observations of the Crab Nebula up to 100 TeV

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    Aims. We measure the Crab Nebula gamma-ray spectral energy distribution in the 100 TeV energy domain and test the validity of existing leptonic emission models at these high energies.Methods. We used the novel very large zenith angle observations with the MAGIC telescope system to increase the collection area above 10 TeV. We also developed an auxiliary procedure of monitoring atmospheric transmission in order to assure proper calibration of the accumulated data. This employs recording optical images of the stellar field next to the source position, which provides a better than 10% accuracy for the transmission measurements.Results. We demonstrate that MAGIC very large zenith angle observations yield a collection area larger than a square kilometer. In only 56 h of observations, we detect the gamma-ray emission from the Crab Nebula up to 100 TeV, thus providing the highest energy measurement of this source to date with Imaging Atmospheric Cherenkov Telescopes. Comparing accumulated and archival MAGIC and Fermi/LAT data with some of the existing emission models, we find that none of them provides an accurate description of the 1 GeV to 100 TeV gamma-ray signal

    Study of the GeV to TeV morphology of the gamma Cygni SNR (G 78.2+2.1) with MAGIC and Fermi-LAT: Evidence for cosmic ray escape

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    Artículo firmado por 183 autores. © ESO 2023. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The financial support of the German BMBF and MPG; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish MINECO (FPA2017-87859-P, FPA2017-85668-P, FPA2017-82729-C6-2-R, FPA2017-82729-C6-6-R, FPA2017-82729-C6-5-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2017-87055-C2-2-P, FPA2017-90566-REDC); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-268/16.12.2019 and the Academy of Finland grant no. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia "Severo Ochoa" SEV-2016-0588 and SEV-2015-0548, the Unidad de Excelencia "María de Maeztu" MDM-2014-0369 and the "la Caixa" Foundation (fellowship LCF/BQ/PI18/11630012), by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382 and by the Brazilian MCTIC, CNPq and FAPERJ. The Fermi LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat a l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucleaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K.A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d'Etudes Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515. This research made use of Astropy (http://www.astropy.org), a community-developed core Python package for Astronomy (Astropy Collaboration 2013, 2018).Context. Diffusive shock acceleration (DSA) is the most promising mechanism that accelerates Galactic cosmic rays (CRs) in the shocks of supernova remnants (SNRs). It is based on particles scattering caused by turbulence ahead and behind the shock. The turbulence upstream is supposedly generated by the CRs, but this process is not well understood. The dominant mechanism may depend on the evolutionary state of the shock and can be studied via the CRs escaping upstream into the interstellar medium (ISM). Aims. Previous observations of the gamma Cygni SNR showed a difference in morphology between GeV and TeV energies. Since this SNR has the right age and is at the evolutionary stage for a significant fraction of CRs to escape, our aim is to understand gamma-ray emission in the vicinity of the gamma Cygni SNR. Methods. We observed the region of the gamma Cygni SNR with the MAGIC Imaging Atmospheric Cherenkov telescopes between 2015 May and 2017 September recording 87 h of good-quality data. Additionally, we analysed Fermi-LAT data to study the energy dependence of the morphology as well as the energy spectrum in the GeV to TeV range. The energy spectra and morphology were compared against theoretical predictions, which include a detailed derivation of the CR escape process and their gamma-ray generation. Results. The MAGIC and Fermi-LAT data allowed us to identify three emission regions that can be associated with the SNR and that dominate at different energies. Our hadronic emission model accounts well for the morphology and energy spectrum of all source components. It constrains the time-dependence of the maximum energy of the CRs at the shock, the time-dependence of the level of turbulence, and the diffusion coefficient immediately outside the SNR shock. While in agreement with the standard picture of DSA, the time-dependence of the maximum energy was found to be steeper than predicted, and the level of turbulence was found to change over the lifetime of the SNR.Depto. de Estructura de la Materia, Física Térmica y ElectrónicaFac. de Ciencias FísicasTRUEGerman BMBFGerman MPGItalian INFNItalian INAFSwiss National Fund SNFERDF under the Spanish MINECOIndian Department of Atomic EnergyJapanese ICRRJapanese University of TokyoJapanese JSPSJapanese MEXTBulgarian Ministry of Education and Science, National RI Roadmap ProjectAcademy of FinlandCentro de Excelencia "Severo Ochoa"Unidad de Excelencia "Maria de Maeztu"Fundación "la Caixa"Croatian Science Foundation (HrZZ) ProjectUniversity of Rijeka ProjectDFG Collaborative Research CentersPolish National Research Centre grantBrazilian MCTICBrazilian CNPqBrazilian FAPERJDOEpu

    A search for dark matter in Triangulum II with the MAGIC telescopes

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    We present the first results from very-high-energy observations of the dwarf spheroidal satellite candidate Triangulum II with the MAGIC telescopes from 62.4 h of good-quality data taken between August 2016 and August 2017. We find no gamma-ray excess in the direction of Triangulum II, and upper limits on both the differential and integral gamma-ray flux are presented. Currently, the kinematics of Triangulum II are affected by large uncertainties leading to a bias in the determination of the properties of its dark matter halo. Using a scaling relation between the annihilation J-factor and heliocentric distance of well-known dwarf spheroidal galaxies, we estimate an annihilation J-factor for Triangulum II for WIMP dark matter of log[J(ann)(0.5 degrees)/GeV2 cm(-5)] = 19.35 +/- 0.37. We also derive a dark matter density profile for the object relying on results from resolved simulations of Milky Way sized dark matter halos. We obtain 95% confidence-level limits on the thermally averaged annihilation cross section for WIMP annihilation into various Standard Model channels. The most stringent limits are obtained in the tau(-)tau(+) final state, where a cross section for annihilation down to = 3.05 x 10(-24) cm(3) s(-1) is excluded. (C) 2020 Elsevier B.V. All rights reserved

    Unraveling the Complex Behavior of Mrk 421 with Simultaneous X-Ray and VHE Observations during an Extreme Flaring Activity in 2013 April

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    We report on a multiband variability and correlation study of the TeV blazar Mrk 421 during an exceptional flaring activity observed from 2013 April 11 to 19. The study uses, among others, data from GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT), Swift, Nuclear Spectroscopic Telescope Array (NuSTAR), Fermi Large Area Telescope, Very Energetic Radiation Imaging Telescope Array System (VERITAS), and Major Atmospheric Gamma Imaging Cherenkov (MAGIC). The large blazar activity and the 43 hr of simultaneous NuSTAR and MAGIC/VERITAS observations permitted variability studies on 15 minute time bins over three X-ray bands (3-7 keV, 7-30 keV, and 30-80 keV) and three very-high-energy (VHE; >0.1 TeV) gamma-ray bands (0.2-0.4 TeV, 0.4-0.8 TeV, and >0.8 TeV). We detected substantial flux variations on multi-hour and sub-hour timescales in all of the X-ray and VHE gamma-ray bands. The characteristics of the sub-hour flux variations are essentially energy independent, while the multi-hour flux variations can have a strong dependence on the energy of the X-rays and the VHE gamma-rays. The three VHE bands and the three X-ray bands are positively correlated with no time lag, but the strength and characteristics of the correlation change substantially over time and across energy bands. Our findings favor multi-zone scenarios for explaining the achromatic/chromatic variability of the fast/slow components of the light curves, as well as the changes in the flux-flux correlation on day-long timescales. We interpret these results within a magnetic reconnection scenario, where the multi-hour flux variations are dominated by the combined emission from various plasmoids of different sizes and velocities, while the sub-hour flux variations are dominated by the emission from a single small plasmoid moving across the magnetic reconnection layer

    Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

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    On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification
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