8,492 research outputs found
Reconstruction methods for acoustic particle detection in the deep sea using clusters of hydrophones
This article focuses on techniques for acoustic noise reduction, signal
filters and source reconstruction. For noise reduction, bandpass filters and
cross correlations are found to be efficient and fast ways to improve the
signal to noise ratio and identify a possible neutrino-induced acoustic signal.
The reconstruction of the position of an acoustic point source in the sea is
performed by using small-volume clusters of hydrophones (about 1 cubic meter)
for direction reconstruction by a beamforming algorithm. The directional
information from a number of such clusters allows for position reconstruction.
The algorithms for data filtering, direction and position reconstruction are
explained and demonstrated using simulated data.Comment: 7 pages, 13 figure
Epstein-Barr-Virus - Ein klinisch relevanter Marker für das Nasopharynxkarzinom? = Epstein-Barr virus - a clinically relevant feature of nasopharyngeal carcinoma? (author's transl.)
Nasopharyngeal carcinoma (NPC) has been linked to Epstein-Barr Virus (EBV) by seroepidemiological evidence and by the regular proof of EBV-DNA in the epithelial tumor cells. We have been able to study the serological parameters of 62 NPC patients of the local ENT-Clinic. All patients were kaukasians in contrast to a previous study by Henle et al. Our results emphasize the remarkable predominance of EBV-IgA antibodies to viral capsid antigen (VCA) and early antigen (EA) in NPC patients and prove the value of the test for the initial diagnosis of the disease. Follow-up studies with subsequent serological tests strongly suggest that this test is related to the stage of the disease. We have also found NPC-typical serological EBV-IgA titers in 3 lymphoepithelial carcinomas of the tonsil and the soft palate. Similar titers have been found in two cases of poorly differentiated carcinomas of the base of the tongue. All these tumors arise in the lymphoepithelial tissue of Waldeyer's ring. We conclude that possibly some carcinomas of Waldeyer's ring are similarly related to EBV as nasopharyngeal carcinomas are
Global meteorological drought – Part 2: Seasonal forecasts
Global seasonal forecasts of meteorological drought using the standardized
precipitation index (SPI) are produced using two data sets as initial
conditions: the Global Precipitation Climatology Centre (GPCC) and the European Centre for Medium-Range Weather Forecasts
(ECMWF) ERA-Interim reanalysis (ERAI); and two seasonal forecasts of precipitation,
the most recent ECMWF seasonal forecast system and climatologically based
ensemble forecasts. The forecast evaluation focuses on the periods where
precipitation deficits are likely to have higher drought impacts, and the
results were summarized over different regions in the world. The verification
of the forecasts with lead time indicated that generally for all regions the
least reduction on skill was found for (i) long lead times using ERAI or
GPCC for monitoring and (ii) short lead times using ECMWF or climatological
seasonal forecasts. The memory effect of initial conditions was found to be
1 month of lead time for the SPI-3, 4 months for the SPI-6 and 6 (or more)
months for the SPI-12. Results show that dynamical forecasts of precipitation
provide added value with skills at least equal to and often above that of
climatological forecasts. Furthermore, it is very difficult to improve on the
use of climatological forecasts for long lead times. Our results also support
recent questions of whether seasonal forecasting of global drought onset was
essentially a stochastic forecasting problem. Results are presented
regionally and globally, and our results point to several regions in the
world where drought onset forecasting is feasible and skilful
Evidence for a Soft Nuclear Equation-of-State from Kaon Production in Heavy Ion Collisions
The production of pions and kaons has been measured in Au+Au collisions at
beam energies from 0.6 to 1.5 AGeV with the Kaon Spectrometer at SIS/GSI. The
K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up
to 6 relative to C+C reactions whereas the corresponding pion ratio is reduced.
The ratio of the K+ meson excitation functions for Au+Au and C+C collisions
increases with decreasing beam energy. This behavior is expected for a soft
nuclear equation-of-state.Comment: 14 pages, 2 figures, accepted for publication in Phys. Rev. Let
Production of Charged Pions, Kaons and Antikaons in Relativistic C+C and C+Au Collisions
Production cross sections of charged pions, kaons and antikaons have been
measured in C+C and C+Au collisions at beam energies of 1.0 and 1.8 AGeV for
different polar emission angles. The kaon and antikaon energy spectra can be
described by Boltzmann distributions whereas the pion spectra exhibit an
additional enhancement at low energies. The pion multiplicity per participating
nucleon M(pi+)/A_part is a factor of about 3 smaller in C+Au than in C+C
collisions at 1.0 AGeV whereas it differs only little for the C and the Au
target at a beam energy of 1.8 AGeV. The K+ multiplicities per participating
nucleon M(K+)/A_part are independent of the target size at 1 AGeV and at 1.8
AGeV. The K- multiplicity per participating nucleon M(K-)/A_part is reduced by
a factor of about 2 in C+Au as compared to C+C collisions at 1.8 AGeV. This
effect might be caused by the absorption of antikaons in the heavy target
nucleus. Transport model calculations underestimate the K-/K+ ratio for C+C
collisions at 1.8 AGeV by a factor of about 4 if in-medium modifications of K
mesons are neglected.Comment: 19 pages, 14 figures, accepted for publication in Eur. Phys. J.
Contribution of the nucleon-hyperon reaction channels to K production in proton-nucleus collisions
The cross sections for producing K mesons in nucleon-hyperon elementary
processes are estimated assuming one-pion exchange and using the experimentally
known pion-hyperon cross sections. The results are implemented in a transport
model which is applied to calculation of proton-nucleus collisions. In
significant difference to earlier estimates for heavy-ion collisions the
inclusion of the nucleon-hyperon cross section roughly doubles the K
production in near-threshold proton-nucleus collisions
Deep Impression: Audiovisual Deep Residual Networks for Multimodal Apparent Personality Trait Recognition
Here, we develop an audiovisual deep residual network for multimodal apparent
personality trait recognition. The network is trained end-to-end for predicting
the Big Five personality traits of people from their videos. That is, the
network does not require any feature engineering or visual analysis such as
face detection, face landmark alignment or facial expression recognition.
Recently, the network won the third place in the ChaLearn First Impressions
Challenge with a test accuracy of 0.9109
Integration of Acoustic Neutrino Detection Methods into ANTARES
The ANTARES Neutrino Telescope is a water Cherenkov detector currently under
construction in the Mediterranean Sea. It is also designed to serve as a
platform for investigations of the deep-sea environment. In this context, the
ANTARES group at the University of Erlangen will integrate acoustic sensors
within the infrastructure of the experiment. With this dedicated setup, tests
of acoustic particle detection methods and deep-sea acoustic background studies
shall be performed. The aim of this project is to evaluate the feasibility of a
future acoustic neutrino telescope in the deep sea operating in the ultra-high
energy regime. In these proceedings, the implementation of the project is
described in the context of the premises and challenges set by the physics of
acoustic particle detection and the integration into an existing
infrastructure.Comment: 6 pages, 5 figures, to appear in the proceedings of the International
ARENA Workshop, May 28-30th, 2006, University of Northumbri
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Multimedia delivery in the future internet
The term “Networked Media” implies that all kinds of media including text, image, 3D graphics, audio
and video are produced, distributed, shared, managed and consumed on-line through various networks,
like the Internet, Fiber, WiFi, WiMAX, GPRS, 3G and so on, in a convergent manner [1]. This white
paper is the contribution of the Media Delivery Platform (MDP) cluster and aims to cover the Networked
challenges of the Networked Media in the transition to the Future of the Internet.
Internet has evolved and changed the way we work and live. End users of the Internet have been confronted
with a bewildering range of media, services and applications and of technological innovations concerning
media formats, wireless networks, terminal types and capabilities. And there is little evidence that the pace
of this innovation is slowing. Today, over one billion of users access the Internet on regular basis, more
than 100 million users have downloaded at least one (multi)media file and over 47 millions of them do so
regularly, searching in more than 160 Exabytes1 of content. In the near future these numbers are expected
to exponentially rise. It is expected that the Internet content will be increased by at least a factor of 6, rising
to more than 990 Exabytes before 2012, fuelled mainly by the users themselves. Moreover, it is envisaged
that in a near- to mid-term future, the Internet will provide the means to share and distribute (new)
multimedia content and services with superior quality and striking flexibility, in a trusted and personalized
way, improving citizens’ quality of life, working conditions, edutainment and safety.
In this evolving environment, new transport protocols, new multimedia encoding schemes, cross-layer inthe
network adaptation, machine-to-machine communication (including RFIDs), rich 3D content as well as
community networks and the use of peer-to-peer (P2P) overlays are expected to generate new models of
interaction and cooperation, and be able to support enhanced perceived quality-of-experience (PQoE) and
innovative applications “on the move”, like virtual collaboration environments, personalised services/
media, virtual sport groups, on-line gaming, edutainment. In this context, the interaction with content
combined with interactive/multimedia search capabilities across distributed repositories, opportunistic P2P
networks and the dynamic adaptation to the characteristics of diverse mobile terminals are expected to
contribute towards such a vision.
Based on work that has taken place in a number of EC co-funded projects, in Framework Program 6 (FP6)
and Framework Program 7 (FP7), a group of experts and technology visionaries have voluntarily
contributed in this white paper aiming to describe the status, the state-of-the art, the challenges and the way
ahead in the area of Content Aware media delivery platforms
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