942 research outputs found
The Unstoppable Intrusion: The Unique Effect of Online Harassment and What the United States Can Ascertain from Other Countries\u27 Attempts to Prevent It
The United States must provide some solution to deal with online harassment. Looking at its fellow nations may be a good way to provide a foundation for changes that need to be mad
The Unstoppable Intrusion: The Unique Effect of Online Harassment and What the United States Can Ascertain from Other Countries\u27 Attempts to Prevent It
The United States must provide some solution to deal with online harassment. Looking at its fellow nations may be a good way to provide a foundation for changes that need to be mad
Line ratios and temperature structure in the deep photosphere
A program to monitor solar cycle variations of the solar flux by using suitable spectral line ratios is going on at Kitt Peak since 1976;the most sensitive to Teff variations are the ratios involving the C I 538.032 nm, whose formation
depth is almost coincident with that of the continuum, and either the Fe I 537.958 or the Ti II 538.103. The temperature sensitivities of those line ratios have been
empirically calibrated by observing the spectra of several solar-like stars by Gray and Livingston, while several attempts to obtain the same calibration theoretically,
through Kurucz’s models of stellar atmospheres, showed difficulty in reproducing quantitatively the experimental results. Because the observed/computed ratio was
approximately the same for both couples of lines, we argued that the problem was in the behaviour of C line, that is more affected than the others by the temperature structure of the deep photosphere, where it is formed. As, in these layers, the gradients of the average temperature are sensibly affected by different treatments of the convection, we compared, first of all, several theoretical models, distinguished from each other in including or not convective overshooting. Then we explored the effects due to variations of the value of the free parameter (α =�/HP ) and those ensued by different versions of the mixing-length theory
SAW RFID-Tags for Mass-Sensitive Detection of Humidity and Vapors
One-port surface acoustic wave (SAW) devices with defined reflector patterns give characteristic signal patterns in the time domain making them identifiable and leading to so-called RFID-Tags. Each sensor responds with a burst of signals, their timed positions giving the identification code, while the amplitudes can be related to the analyte concentration. This paper presents the first combination of such a transducer with chemically sensitive layer materials. These include crosslinked polyvinyl alcohol for determining relative humidity and tert-butylcalix[4]arene for detecting solvent vapors coated on the free space between the reflectors. In going from the time domain to the frequency domain by Fourier transformation, changes in frequency and phase lead to sensor responses. Hence, it is possible to measure the concentration of tetrachloroethene in air down to 50 ppm, as well as 1% changes in relative humidity
Development of a surgical stereo endoscopic image dataset for validating 3D stereo reconstruction algorithms
In the last decades, endoscopic stereo images have been exploited to retrieve tissue surface information of the surgical site using 3D reconstruction algorithms. The application of such algorithms in Computer Assisted Surgery (CAS) tools for Minimally Invasive Surgery (MIS) requires a robust validation process in order to guarantee reliability and safety. 3D reconstruction algorithms are commonly evaluated comparing their result with respect to a reference Ground Truth (GT). However, few datasets providing endoscopic images and GT are openly available.
Considering the increasing necessity of surgical datasets, the aim of this work is the generation of an Endoscopic Abdominal Stereo (EndoAbS) dataset composed of stereo-images with associated GT for 3D stereo-reconstruction algorithm validation. To recreate the surgical scenario, a polyurethane surgical phantom abdomen was built. Images were captured with a stereo-endoscope, while for acquiring the GT a laser scanner (calibrated with respect to the stereoendoscope) was used. This dataset is openly available on-line for the benefit of the CAS community
The correlation of synthetic UV color vs Mg II index along the solar cycle
Modeling of planets' climate and habitability requires as fundamental input
the UV emission of the hosting star. \citet{lovric2017} employed SORCE/SOLSTICE
solar observations to introduce a UV color index which is a descriptor of the
UV radiation that modulates the photochemistry of planets atmospheres. After
correcting the SOLSTICE data for residual instrumental effects that produced
asymmetric signals during different phases of the cycles analyzed, the authors
found that the UV color index is linearly correlated with the Mg II index.In
this paper we employ an irradiance reconstruction technique to synthetize the
UV color and Mg II index with the purpose of investigating whether the
correction applied by \citet{lovric2017} to SORCE/SOLSTICE data might have
compensated for solar variations, and to investigate the physical mechanisms
that produce such a strong correlation between the UV color index and the solar
activity. Reconstructed indices reproduce very well the observations and
present the same strong linear dependence. Moreover our reconstruction, which
extends back to 1989, shows that the UV color - Mg II index relation can be
described by the same linear relation for almost three cycles, thus ruling out
an overcompensation of SORCE/SOLTICE data in the analysis of
\citet{lovric2017}. We suggest that the strong correlation between the indices
results from the fact that most of the Far- and Middle- UV radiation originates
in the chromosphere, where atmosphere models of quiet and magnetic features
present similar temperature and density gradients.Comment: Accepted in Ap
Validazione di un innovativo sistema di telemonitoraggio e creazione di percorsi diagnostico-terapeutici per l'identificazione dei meccanismi di presentazione ed evoluzione della fibrillazione atriale.
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Diseño y cálculo de una red colectora cloacal.
Práctica Supervisada (IC)--FCEFN-UNC, 2016Comprende una red colectora cloacal a gravedad que permitirá la conducción del 100% de los efluentes cloacales domésticos generados en el interior de las urbanizaciones Solares y Prados de Manantiales ubicados en la zona suroeste de la ciudad de Córdoba, Provincia de Córdoba
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