9,832 research outputs found
Forward Vehicle Collision Warning Based on Quick Camera Calibration
Forward Vehicle Collision Warning (FCW) is one of the most important
functions for autonomous vehicles. In this procedure, vehicle detection and
distance measurement are core components, requiring accurate localization and
estimation. In this paper, we propose a simple but efficient forward vehicle
collision warning framework by aggregating monocular distance measurement and
precise vehicle detection. In order to obtain forward vehicle distance, a quick
camera calibration method which only needs three physical points to calibrate
related camera parameters is utilized. As for the forward vehicle detection, a
multi-scale detection algorithm that regards the result of calibration as
distance priori is proposed to improve the precision. Intensive experiments are
conducted in our established real scene dataset and the results have
demonstrated the effectiveness of the proposed framework
The OPERA experiment Target Tracker
The main task of the Target Tracker detector of the long baseline neutrino
oscillation OPERA experiment is to locate in which of the target elementary
constituents, the lead/emulsion bricks, the neutrino interactions have occurred
and also to give calorimetric information about each event. The technology used
consists in walls of two planes of plastic scintillator strips, one per
transverse direction. Wavelength shifting fibres collect the light signal
emitted by the scintillator strips and guide it to both ends where it is read
by multi-anode photomultiplier tubes. All the elements used in the construction
of this detector and its main characteristics are described.Comment: 25 pages, submitted to Nuclear Instrument and Method
Preliminary results of the AMIGA engineering array at the Pierre Auger Observatory
The Auger Muons and Infill for the Ground Array (AMIGA) aims to both extend
the detection range of the Pierre Auger Observatory down to energies and to measure the muon content of extensive air
showers. To accomplish these goals, its detection system is composed of an
array of coupled water-Cherenkov and scintillation detectors deployed in a
graded triangular grid of 433 and 750\,m spacings. At each position, the
scintillation detector is buried deep so as to shield it from
the air shower electromagnetic component and thus only measure the muon
component. These muon detectors have area split into modules,
each of them highly segmented in 64 plastic-scintillator strips with an
embedded wavelength-shifter optical fiber to transport light to an optical
sensor located at the center of the module. During the engineering array phase
(finished in November 2017) two module areas ( and
) and two optical sensors (photo-multiplier tubes and
silicon-photomultipliers) were tested. In this work, we present the final
performance of the muon detectors equipped with silicon-photomultipliers which
were thereafter selected as the baseline design for the AMIGA production phase.
Analyses and results are based both on laboratory and field measurements.Comment: Proceeding of the UHECR 2018 conference, submitted to the forthcoming
EPJ Web of Conference
GARFIELD + RCo Digital Upgrade: a Modern Set-up for Mass and Charge Identification of Heavy Ion Reaction Products
An upgraded GARFIELD + Ring Counter (RCo) apparatus is presented with
improved performances as far as electronics and detectors are concerned. On one
side fast sampling digital read out has been extended to all detectors,
allowing for an important simplification of the signal processing chain
together with an enriched extracted information. On the other side a relevant
improvement has been made in the forward part of the setup (RCo): an increased
granularity of the CsI(Tl) crystals and a higher homogeneity in the silicon
detector resistivity. The renewed performances of the GARFIELD + RCo array make
it suitable for nuclear reaction measurements both with stable and with
Radioactive Ion Beams (RIB), like the ones foreseen for the SPES facility,
where the Physics of Isospin can be studied.Comment: 13 pages, 19 figures - paper submitted to Eur. Phys. J.
AMS tracking in-orbit performance
AMS-02 is a high precision magnetic spectrometer for cosmic rays in the GeV
to TeV energy range. Its tracker consists of nine layers of double-sided
silicon microstrip sensors. They are used to locate the trajectories of cosmic
rays in the 0.14 T field of a cylindrical magnet, thus measuring their rigidity
and charge sign. In addition, they deliver a high resolution measurement
of the absolute charge . The detector has been designed to operate in
space with a position resolution of about 10 m for each hit and charge
identification capabilities up to . In this talk I describe the
performance in orbit of this detector component and its impact on the overall
performance of the spectrometer.Comment: 24th International Workshop on Vertex Detectors, 1-5 June 2015, Santa
Fe, New Mexico, US
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