239 research outputs found
EUMSSI team at the MediaEval Person Discovery Challenge 2016
We present the results of the EUMSSI team’s participation in the Multimodal Person Discovery task. The goal is to identify all people who simultaneously appear and speak in a video corpus. In the proposed system, besides improving each modality, we emphasize on the ranking of multiple results from both audio stream and visual stream
Joint speech and overlap detection: a benchmark over multiple audio setup and speech domains
Voice activity and overlapped speech detection (respectively VAD and OSD) are
key pre-processing tasks for speaker diarization. The final segmentation
performance highly relies on the robustness of these sub-tasks. Recent studies
have shown VAD and OSD can be trained jointly using a multi-class
classification model. However, these works are often restricted to a specific
speech domain, lacking information about the generalization capacities of the
systems. This paper proposes a complete and new benchmark of different VAD and
OSD models, on multiple audio setups (single/multi-channel) and speech domains
(e.g. media, meeting...). Our 2/3-class systems, which combine a Temporal
Convolutional Network with speech representations adapted to the setup,
outperform state-of-the-art results. We show that the joint training of these
two tasks offers similar performances in terms of F1-score to two dedicated VAD
and OSD systems while reducing the training cost. This unique architecture can
also be used for single and multichannel speech processing
CRF-Based Context Modeling for Person Identification in Broadcast Videos
International audienceno abstrac
Speaker segmentation and clustering
This survey focuses on two challenging speech processing topics, namely: speaker segmentation and speaker clustering. Speaker segmentation aims at finding speaker change points in an audio stream, whereas speaker clustering aims at grouping speech segments based on speaker characteristics. Model-based, metric-based, and hybrid speaker segmentation algorithms are reviewed. Concerning speaker clustering, deterministic and probabilistic algorithms are examined. A comparative assessment of the reviewed algorithms is undertaken, the algorithm advantages and disadvantages are indicated, insight to the algorithms is offered, and deductions as well as recommendations are given. Rich transcription and movie analysis are candidate applications that benefit from combined speaker segmentation and clustering. © 2007 Elsevier B.V. All rights reserved
Challenge of Chimpanzees Immunized with a Recombinant Canarypox-HIV-1 Virus
AbstractTo evaluate the potential protective efficacy of a live recombinant human immunodeficiency virus type 1 (HIV-1) canarypox vaccine candidate, two chimpanzees were immunized five times with ALVAC-HIV-1 vCP250, a recombinant canarypox virus that expresses the HIV-1IIIB(LAI)gp120/TM,gag,and protease gene products. One month after the last booster inoculation, the animals were challenged by intravenous injection of cell-associated virus in the form of peripheral blood mononuclear cells from an HIV-1IIIB(LAI)-infected chimpanzee. One chimpanzee with a neutralizing antibody titer to HIV-1IIIB(LAI)of 128 at the time of challenge was protected, whereas both the second animal, with a neutralizing antibody titer of 32, and a naive control animal became infected. At 5 months after challenge, the protected chimpanzee and a third animal, previously immunized with various HIV-1MNantigens, were given a booster inoculation. The two animals were challenged intravenously 5 weeks later with twenty 50% tissue culture infectious doses of cell-free HIV-1DH12, a heterologous subtype B isolate. Neither chimpanzee had neutralizing antibodies to HIV-1DH12, and neither one was protected from infection with this isolate. The immune responses elicited by vaccination against HIV-1IIIB(LAI)or HIV-1MNdid not, therefore, protect the animals from challenge with the heterologous cell-free HIV-1DH12
ISGRI: the INTEGRAL Soft Gamma-Ray Imager
For the first time in the history of high energy astronomy, a large CdTe
gamma-ray camera is operating in space. ISGRI is the low-energy camera of the
IBIS telescope on board the INTEGRAL satellite. This paper details its design
and its in-flight behavior and performances. Having a sensitive area of 2621
cm with a spatial resolution of 4.6 mm, a low threshold around 12 keV and
an energy resolution of 8% at 60 keV, ISGRI shows absolutely no signs of
degradation after 9 months in orbit. All aspects of its in-flight behavior and
scientific performance are fully nominal, and in particular the observed
background level confirms the expected sensitivity of 1 milliCrab for a 10s
observation.Comment: INTEGRAL A&A special issu
Gene therapy: the end of the rainbow?
The increased understanding of the molecular basis of oral cancer has led to expectations that correction of the genetic defects will lead to improved treatments. Nevertheless, the first clinical trials for gene therapy of oral cancer occurred 20 years ago, and routine treatment is still not available. The major difficulty is that genes are usually delivered by virus vectors whose effects are weak and temporary. Viruses that replicate would be better, and the field includes many approaches in that direction. If any of these are effective in patients, then gene therapy will become available in the next few years. Without significant advances, however, the treatment of oral cancer by gene therapy will remain as remote as the legendary pot of gold at the end of the rainbow
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