306 research outputs found
El Método "Software Factory": acciones para realizar prácticas más realistas, usando herramientasWeb de trabajo colaborativo, y trabajo a distancia
El método Software Factory (SF) consiste en llevar
a cabo acciones y aplicar herramientas informáticas,
con dos finalidades: (1) hacer que las prácticas de
asignaturas tecnológicas (en un sentido amplio) sean
lo más parecidas que sea posible al trabajo real en
la empresa o la industria y (2) difundir el uso de
herramientas Web que permitan nuevas formas de
trabajo ágiles y dinámicas, como por ejemplo el
teletrabajo, el trabajo móvil y el trabajo colaborativo
a distancia. Este artículo describe las experiencias de
los autores en este sentido.SUMMARY -- The SF method is meant to take some actions and
to apply software tools, with two purposes: (1) to
make the practical work of technology subjects (in
a broad sense) to resemble as much as possible
the actual work in business or industry, and (2) to
spread the use of Web tools that allow new flexible
and dynamic forms of work, such as teleworking,
mobile working and remote collaborative work. This
article describes the experiences of the authors in
this regard.Peer Reviewe
Modeling of Mid-IR Amplifier Based on an Erbium-Doped Chalcogenide Microsphere
An optical amplifier based on a tapered fiber and an Er3+-doped chalcogenide microsphere is designed and optimized. A dedicated 3D numerical model, which exploits the coupled mode theory and the rate equations, is used. The main transitions among the erbium energy levels, the amplified spontaneous emission, and the most important secondary transitions pertaining to the ion-ion interactions have been considered. Both the pump and signal beams are efficiently injected and obtained by a suitable design of the taper angle and the fiber-microsphere gap. Moreover, a good overlapping between the optical signals and the rare-earth-doped region is also obtained. In order to evaluate the amplifier performance in reduced computational time, the doped area is partitioned in sectors. The obtained simulation results highlight that a high-efficiency midinfrared amplification can be obtained by using a quite small microsphere
TEIdown: Uso de Markdown extendido para el marcado automático de documentos TEI
La creación de nuevos documentos XML, desde cero o a partir de texto plano, puede ser una tarea difícil, lenta y propensa a errores, sobre todo cuando el vocabulario de marcado utilizado es rico y complejo, como es el caso del TEI. Por lo general, lleva bastante tiempo lograr que el documento valide por primera vez.Juntando el espíritu del viejo SGML, y los principios del Markdown, llegamos a la idea del proyecto TEIdown, que consiste en una ampliación de la sintaxis del Markdown para crear documentos XML-TEI, y los programas de transformación correspondientes. Con este enfoque, es fácil obtener un documento TEI válido en un tiempo muy corto, evitando pasar por una larga lista de errores de validación
Efficiency Enhancement for an S-Band Axial Vircator Using 5-Stage Two-Step Tapered Radiators
An S-band multistage axial virtual cathode oscillator with efficiency enhancement for high pulsed power electromagnetic applications is presented. The Particle-in-Cell (PIC) results of the designed 5-stage Vircator, with two-step negative tapering in the reflectors, carried out by CST Studio suite 2021 simulation code show a peak power value of 5.54 GW and an efficiency value of 13.65% at 2.45 GHz, under a beam voltage and current equal to 520 kV and 20 kA, respectively
Correlation measurements in high-multiplicity events
Requirements for correlation measurements in high--multiplicity events are
discussed. Attention is focussed on detection of so--called hot spots,
two--particle rapidity correlations, two--particle momentum correlations (for
quantum interferometry) and higher--order correlations. The signal--to--noise
ratio may become large in the high--multiplicity limit, allowing meaningful
single--event measurements, only if the correlations are due to collective
behavior.Comment: MN 55455, 20 pages, KSUCNR-011-92 and TPI-MINN-92/47-T (revised).
Revised to correct typo in equation (30), and to fill in a few steps in
calculations. Now published as Phys. Rev. C 47 (1993) 232
Looking for the first time into the heart of the blazar TXS 2013+370
The compact radio source TXS 2013+370 is a γ-ray blazar which is located at a redshift of z = 0.859 at a galactic latitude b = 1.2°. We observed the source with Very Long Baseline Interferometry (VLBI) at 15, 43 and 86 GHz and studied the morphology and the kinematic properties of the jet. The VLBI data were then combined with flux density variability measurements at 15 and 235 GHz and with the available γ-ray light curve in the period 2008-2017. A cross-correlation analysis was performed to investigate the existence of a correlation between the variability observed in the different bands. The preliminary results of our study showed that the most prominent flares and maxima stem from the central VLBI region and most likely are associated with the nuclear region, namely the core, indicating that the activity is caused by the passage of traveling shocks through the core region. In the course of our analysis, we present for the first time a 86 GHz Global Millimeter VLBI Array (GMVA) image of the innermost jet region
Higher Order Processes in Electromagnetic Production of Electron Positron Pairs in Relativistic Heavy Ion Collisions
We study higher-order effects in the electromagnetic production of
electron-positron pairs in relativistic heavy ion collisions. Treating the
field of the heavy ions as an external field and neglecting the interaction
among electrons and positrons, we show that the -pair creation amplitude is
the antisymmetrised product of one-pair creation amplitudes and the vacuum
amplitude. Neglecting contributions coming from exchange terms, we show that
the total probability for pairs is approximately a Poisson distribution. We
investigate further the structure of the reduced one-pair amplitude,
concentrating especially on multiple-particle corrections. We calculate the
first of these corrections in second order Magnus theory based on our previous
result in second-order Born approximation for impact parameter zero.
Explicit calculations show that the total probability is increased up to 10 \%
by this correction for realistic collider parameters. The calculations can also
be used to confirm the use of the Poisson distribution for the total
probability.Comment: 29 pages RevTeX and 12 uuencoded figures (compressed postscript
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