2,881 research outputs found
Danse espagnole
https://digitalcommons.library.umaine.edu/mmb-ps/1087/thumbnail.jp
Occupancy Estimation Using Low-Cost Wi-Fi Sniffers
Real-time measurements on the occupancy status of indoor and outdoor spaces
can be exploited in many scenarios (HVAC and lighting system control, building
energy optimization, allocation and reservation of spaces, etc.). Traditional
systems for occupancy estimation rely on environmental sensors (CO2,
temperature, humidity) or video cameras. In this paper, we depart from such
traditional approaches and propose a novel occupancy estimation system which is
based on the capture of Wi-Fi management packets from users' devices. The
system, implemented on a low-cost ESP8266 microcontroller, leverages a
supervised learning model to adapt to different spaces and transmits occupancy
information through the MQTT protocol to a web-based dashboard. Experimental
results demonstrate the validity of the proposed solution in four different
indoor university spaces.Comment: Submitted to Balkancom 201
tvf-EMD based time series analysis of Be of the CTBTO-IMS network
A methodology of adaptive time series analysis based on Empirical Mode
Decomposition (EMD) has been employed to investigate Be activity
concentration variability, along with temperature. Analysed data were sampled
at ground level by 28 different stations of the CTBTO-IMS network. The adaptive
nature of the EMD algorithm allows it to deal with data that are both nonlinear
and non-stationary, making no a priori assumptions on the expansion basis. Main
purpose of the adopted methodology is to characterise the possible presence of
a trend, occurrence of AM-FM modulation of relevant oscillatory modes,
residuals distributions and outlier occurrence. Trend component is first
estimated via simple EMD and removed. The recent time varying filter EMD
(tvf-EMD) technique is then employed to extract local narrow band oscillatory
modes from the data. To establish their relevance, a denoising step is then
carried out, employing both the Hurst exponent as a thresholding parameter and
further testing their statistical significance against white noise. The ones
that pass the denoising step are considered to be meaningful oscillatory modes
of the data, and their AM-FM modulation is investigated. Possible applications
of the adopted methodology regarding site characterisation and suggestions for
further research are given in the conclusions
Non-vascular interventional procedures: effective dose to patient and equivalent dose to abdominal organs by means of dicom images and Monte Carlo simulation
This study evaluates X-ray exposure in patient undergoing abdominal extra-vascular interventional procedures by means of Digital Imaging and COmmunications in Medicine (DICOM) image headers and Monte Carlo simulation. The main aim was to assess the effective and equivalent doses, under the hypothesis of their correlation with the dose area product (DAP) measured during each examination. This allows to collect dosimetric information about each patient and to evaluate associated risks without resorting to in vivo dosimetry. The dose calculation was performed in 79 procedures through the Monte Carlo simulator PCXMC (A PC-based Monte Carlo program for calculating patient doses in medical X-ray examinations), by using the real geometrical and dosimetric irradiation conditions, automatically extracted from DICOM headers. The DAP measurements were also validated by using thermoluminescent dosimeters on an anthropomorphic phantom. The expected linear correlation between effective doses and DAP was confirmed with an R(2) of 0.974. Moreover, in order to easily calculate patient doses, conversion coefficients that relate equivalent doses to measurable quantities, such as DAP, were obtained
The fundamental relation between supermassive black holes and their host galaxies
We study the correlations between supermassive black holes (BHs) and their host galaxies, using a sample of 83 BH masses collected from the most recent and reliable spatially resolved estimates available from the literature. We confirm the mono- and bivariate correlations between SMBHs and the bulges of their host galaxies, confirming that the correlation with the effective velocity dispersion is not significantly improved by higher dimensionality. Instead, pseudo-bulges do not seem to correlate with their SMBHs, probably because their secular evolution is often unable to trigger accretion onto the central BH. We then present a novel approach aimed at finding the fundamental relation between SMBHs and their host galaxies. For the first time, we analytically combine BH masses with the Fundamental Plane (FP), showing that M_(BH)–σ_e appears to be the fundamental relation rather than a putative ‘BH Fundamental Plane’ of the kind M_(BH)–σ_e–R_e. These results can be explained by a picture which sees the M_(BH)–σ_e relation as a natural outcome of the change in AGN feedback from momentum-driven to energy-driven. The other scaling relations are then established through the FP
The Fundamental Relation between Supermassive Black Holes and Their Host Galaxies
We study the correlations between Supermassive Black Holes (BH) and their
host galaxies, using a sample of 83 BH masses collected from the most recent
and reliable spatially resolved estimates available from the literature. We
confirm the mono- and bivariate correlations between SMBHs and the bulges of
their host galaxies, confirming that the correlation with the effective
velocity dispersion is not significantly improved by higher dimensionality.
Instead, pseudobulges do not seem to correlate with their SMBHs, probably
because their secular evolution is often unable to trigger accretion onto the
central BH. We then present a novel approach aimed at finding the fundamental
relation between SMBHs and their host galaxies. For the first time, we
analytically combine BH masses with the Fundamental Plane (FP), showing that
Mbh-sigma_e appears to be the fundamental relation rather than a putative "BH
Fundamental Plane" of the kind Mbh-sigma_e-R_e. These results can be explained
by a picture which sees the Mbh-sigma_e relation as a natural outcome of the
change in AGN feedback from momentum- to energy-driven. The other scaling
relations are then established through the FP.Comment: 15 pages, 11 figures, accepted by MNRA
Adaptation of an i-voting scheme to Italian Elections for Citizens Abroad
We adapt the Ara´ujo-Traor´e protocol to Italian elections,
with emphasis on anti-coercion measures. In this short paper we focus
on a new method for managing anti-coercion credentials for each voter
Shear-Thinning Fluid Flow in Variable-Aperture Channels
Non-Newtonian fluid flow in a single fracture is a 3-D nonlinear phenomenon that is often averaged across the fracture aperture and described as 2-D. To capture the key interactions between fluid rheology and spatial heterogeneity, we adopt a simplified geometric model to describe the aperture variability, consisting of adjacent one-dimensional channels with constant aperture, each drawn from an assigned aperture distribution. The flow rate is then derived under the lubrication approximation for the two limiting cases of an external pressure gradient that is parallel/perpendicular to the channels; these two arrangements provide upper and lower bounds to the fracture conductance. The fluid rheology is described by the Prandtl–Eyring shear-thinning model. Novel closed-form results for the flow rate and hydraulic aperture are derived and discussed; different combinations of the parameters that describe the fluid rheology and the variability of the aperture field are considered. The flow rate values are very sensitive to the applied pressure gradient and to the shape of the distribution; in particular, more skewed distribution entails larger values of a dimensionless flow rate. Results for practical applications are compared with those valid for a power-law fluid and show the effects on the fracture flow rate of a shear stress plateau
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