89 research outputs found
Fingerprint Recognition for Children
This document is the final report of the Fingerprint Recognition Study of Children below the Age of 12 Years . The key findings of the study are:
âą Growth has limited influence on fingerprint recognition
âą Size (in terms of the dimensions of the relevant fingerprint characteristics) does not constitute any theoretical barrier for automated fingerprint recognition.
âą Image quality (in terms of low contrast and distortion effects) is the ultimate problem for child fingerprints, and image quality is strongly influenced by size.
âą Relevant quality metrics for fingerprints need revision with regard to the children case.
âą Isotropic growth model may serve as a good approximation to cover changes over time.
âą Alternative acquisition devices for fingerprints should be seriously considered in the future.
Apart from these major findings, the report provides a number of recommendations to improve the process of acquiring fingerprints from children.JRC.G.7-Digital Citizen Securit
Medical Age Assessment of Juvenile Migrants
An important aspect of the reception of unaccompanied children in migration is the question of their age. As these young people frequently arrive without reliable documents, their age might be called into question. This puts into focus age assessment, the attempt by authorities to estimate the (chronological) age of a person, in the absence of reliable documentation regarding age. As there is no such simple technique for humans as counting the age rings of trees, any existing age assessment approach is subject to discussions and possibly even disagreements.
Medical methods for age determination are usually the ones considered as more problematical for a number of reasons. The most important class of medical methods are those based on the observation of age markers, i.e. somatic indicators that change in a given way with age. As a large number of scientific studies has investigated this relationship in detail, it is assumed that this method allows for reliable and reproducible conclusion about the true age of a person.
This ambitious claim is not unchallenged. In addition to doubts about the real precision of medical methods, there are also health and ethical issues. On the other hand, the high potential to establish age estimation on objective criteria, thereby reducing the dependence on individual expert opinion, has raised high expectations and attention on age markers. The current report aims to analyse to what extent these expectations can be met.JRC.E.6-Demography, Migration and Governanc
Gaps and challenges in the knowledge of migration and demography: Proposals for new approaches and solutions
This report is the result of the research carried out under Task 5 of DG JRC's Task Force on Migration and Demography. The report is structured following the four pillars outlined in the European Agenda on Migration. A few additional chapters are included to cover some aspects not explicitly touched on in the Agenda, but still considered to have a relevant role in migration and an impact on demographic trends.
Contributions answered the following questions:
1. What are main points/findings/debates concerning the priority area/sub-category allocated to you?
2. How does the information gathered in question 1 relate to the scope and the structure of the European Agenda on Migration?
3. What current information and data is available, who is producing it and how?
4. What and where are the main gaps and challenges?
5. What are the solutions or approaches to address these gaps and challenges based upon your research?
To complement this review, two Annexes were created: the first being an overview of the main gaps and challenges as well as the suggested solutions for the whole report (Annex 1), and the second being a preliminary inventory of available migration data and data sources (Annex 2).JRC.E.6-Demography, Migration and Governanc
Resource-aware Research on Universe and Matter: Call-to-Action in Digital Transformation
Given the urgency to reduce fossil fuel energy production to make climate
tipping points less likely, we call for resource-aware knowledge gain in the
research areas on Universe and Matter with emphasis on the digital
transformation. A portfolio of measures is described in detail and then
summarized according to the timescales required for their implementation. The
measures will both contribute to sustainable research and accelerate scientific
progress through increased awareness of resource usage. This work is based on a
three-days workshop on sustainability in digital transformation held in May
2023.Comment: 20 pages, 2 figures, publication following workshop 'Sustainability
in the Digital Transformation of Basic Research on Universe & Matter', 30 May
to 2 June 2023, Meinerzhagen, Germany, https://indico.desy.de/event/3748
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
Search for dark matter produced in association with bottom or top quarks in âs = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fbâ1 of protonâproton collision data recorded by the ATLAS experiment at âs = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
Multiple Scenario Generation of Subsurface Models:Consistent Integration of Information from Geophysical and Geological Data throuh Combination of Probabilistic Inverse Problem Theory and Geostatistics
Neutrinos with energies above 1017 eV are detectable with the Surface Detector Array of the Pierre Auger Observatory. The identification is efficiently performed for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for Earth-skimming \u3c4 neutrinos with nearly tangential trajectories relative to the Earth. No neutrino candidates were found in 3c 14.7 years of data taken up to 31 August 2018. This leads to restrictive upper bounds on their flux. The 90% C.L. single-flavor limit to the diffuse flux of ultra-high-energy neutrinos with an E\u3bd-2 spectrum in the energy range 1.0
7 1017 eV -2.5
7 1019 eV is E2 dN\u3bd/dE\u3bd < 4.4
7 10-9 GeV cm-2 s-1 sr-1, placing strong constraints on several models of neutrino production at EeV energies and on the properties of the sources of ultra-high-energy cosmic rays
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