571 research outputs found
Performance evaluation of a Wi-Fi-based multi-node network for distributed audio-visual sensors
The experimental research described in this manuscript proposes a complete network system for distributed multimedia acquisition by mobile remote nodes, streaming to a central unit, and centralized real-time processing of the collected signals. Particular attention is placed on the hardware structure of the system and on the research of the best network performances for an efficient and secure streaming. Specifically, these acoustic and video sensors, microphone arrays and video cameras respectively, can be employed in any robotic vehicles and systems, both mobile and fixed. The main objective is to intercept unidentified sources, like any kind of vehicles or robotic vehicles, drones, or people whose identity is not a-priory known whose instantaneous location and trajectory are also unknown. The proposed multimedia network infrastructure is analysed and studied in terms of efficiency and robustness, and experiments are conducted on the field to validate it. The hardware and software components of the system were developed using suitable technologies and multimedia transmission protocols to meet the requirements and constraints of computation performance, energy efficiency, and data transmission security
Management of oromandibular dystonia with botulinum A toxin: a series of cases.
Oromandibular dystonia is a disorder of movement that is often misdiagnosed. We present our experience of six patients treated with botulinum A toxin, for whom we recorded the symptoms, the group of muscles targeted, and the quantity of botulinum toxin used. We used the Glasgow Benefit Inventory (GBI) questionnaire to record and analyse outcomes after treatment. Five of the six patients had a good outcome as recorded by the GBI, the mean (SD) score of which was +40 (28), which reflected that the patients were well satisfied. The overall improvement in the categories of general health, social health, and physical health were 82%, 37%, and 31%, respectively. Botulinum type A toxin is an effective treatment of oromandibular dystonia. It is important for clinicians to recognise the condition, as treatment is well-tolerated and can improve quality of life
Discovery of the Optical Transient of the Gamma Ray Burst 990308
The optical transient of the faint Gamma Ray Burst 990308 was detected by the
QUEST camera on the Venezuelan 1-m Schmidt telescope starting 3.28 hours after
the burst. Our photometry gives , , , and for times ranging from 3.28 to 3.47
hours after the burst. The colors correspond to a spectral slope of close to
. Within the standard synchrotron fireball model,
this requires that the external medium be less dense than , the
electrons contain of the shock energy, and the magnetic field energy
must be less than 24% of the energy in the electrons for normal interstellar or
circumstellar densities. We also report upper limits of at 132 s
(with LOTIS), from 132-1029s (with LOTIS), at 28.2 min
(with Super-LOTIS), and a 8.5 GHz flux of at 110 days (with the
Very Large Array). WIYN 3.5-m and Keck 10-m telescopes reveal this location to
be empty of any host galaxy to and . The lack of a host
galaxy likely implies that it is either substantially subluminous or more
distant than a red shift of .Comment: ApJ Lett submitted, 5 pages, 2 figures, no space for 12 coauthor
TNOs are Cool: A survey of the trans-Neptunian region V. Physical characterization of 18 Plutinos using Herschel PACS observations
We present Herschel PACS photometry of 18 Plutinos and determine sizes and
albedos for these objects using thermal modeling. We analyze our results for
correlations, draw conclusions on the Plutino size distribution, and compare to
earlier results. Flux densities are derived from PACS mini scan-maps using
specialized data reduction and photometry methods. In order to improve the
quality of our results, we combine our PACS data with existing Spitzer MIPS
data where possible, and refine existing absolute magnitudes for the targets.
The physical characterization of our sample is done using a thermal model.
Uncertainties of the physical parameters are derived using customized Monte
Carlo methods. The correlation analysis is performed using a bootstrap Spearman
rank analysis. We find the sizes of our Plutinos to range from 150 to 730 km
and geometric albedos to vary between 0.04 and 0.28. The average albedo of the
sample is 0.08 \pm 0.03, which is comparable to the mean albedo of Centaurs,
Jupiter Family comets and other Trans-Neptunian Objects. We were able to
calibrate the Plutino size scale for the first time and find the cumulative
Plutino size distribution to be best fit using a cumulative power law with q =
2 at sizes ranging from 120-400 km and q = 3 at larger sizes. We revise the
bulk density of 1999 TC36 and find a density of 0.64 (+0.15/-0.11) g cm-3. On
the basis of a modified Spearman rank analysis technique our Plutino sample
appears to be biased with respect to object size but unbiased with respect to
albedo. Furthermore, we find biases based on geometrical aspects and color in
our sample. There is qualitative evidence that icy Plutinos have higher albedos
than the average of the sample.Comment: 18 pages, 8 figures, 8 tables, accepted for publication in A&
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