In this paper, we present a scalable architecture to compute, visualize and interact with 3D dynamic models of real scenes. This architecture is designed for mixed reality applications requiring such ...dynamic models, tele-immersion for instance. Our system consists in 3 main parts: the acquisition, based on standard firewire cameras; the computation, based on a distribution scheme over a cluster of PC and using a recent shape-from-silhouette algorithm which leads to optimally precise 3D models; the visualization, which is achieved on a multiple display wall. The proposed distribution scheme ensures scalability of the system and hereby allows control over the number of cameras used for acquisition, the frame-rate, or the number of projectors used for high resolution visualization. To our knowledge this is the first completely scalable vision architecture for real time 3D modeling, from acquisition to visualization through computation. Experimental results show that this framework is very promising for real time 3D interactions.
8 patients over 30 years of age with a thyroglossal cyst, who had not been operated on before and who underwent excision of the cyst by a Sistrunk procedure, are described. In 8 additional patients, ...a wait-and-see policy was adopted. Follow-up data of these 16 patients are reported 1.5-14 years after their last visit to the hospital. There were no recurrences in the group of treated patients. In the group of untreated patients, the cyst remained unchanged in 1, decreased in size in 3 and disappeared completely in the remaining 4 patients. The present study indicates that removal of a thyroglossal cyst in patients over 30 years of age is not obligatory.
Gnamptogenys menadensis is an arboreal nester that forages opportunistically almost exclusively on vegetation, sometimes recruiting others to participate in prey retrieval. The three-dimensional ...characteristics of vegetation suggest that functions describing recruitment decision thresholds or the pattern of recruitment in arboreal species may differ from those predicted by optimal foraging theory. To examine the effects of prey abundance and distance on the recruitment dynamics of G. menadensis, we baited nests with one termite, five termites or a number of termites between 20 and 40 either near to or far from the entrance and observed the ensuing behaviors. G. menadensis recruited others when encountering multiple termites regardless of the termite pile's distance from the nest, although a few individuals remained at the site and defended the resource. The pattern of arrivals at the site indicates that the majority and sometimes all arrivals were recruited from the branch trails. In combination, these results suggest that the architecture of the foraging habitat, which limits available return routes to the nest and thus increases encounter probabilities with potential recruits, shaped the process of information transfer and generated a collective pattern of foraging and prey retrieval.
In Quebec, the Child's Protection law protects the child from birth until 18 years of age when child abuse or neglect is suspected. Since 1990, the program of the Child Protection Clinic of ...Sainte-Justine Hospital (Montreal) offers a special unit for evaluation and prevention of child abuse and neglect, constituted by a multidisciplinary team including five pediatricians. About 500 children are referred each year in external consultations or from hospital units. In addition, the pediatricians participate in the "programme Santé-Enfance-Jeunesse", a prevention program in the Montreal area. They also act as expert witnesses in court. Thus Quebec's pediatricians fully participate in a child's protection with their activities in different levels of diagnosis, management and prevention of child abuse and neglect.
The Interface Region Imaging Spectrograph (IRIS) small explorer spacecraft provides simultaneous spectra and images of the photosphere, chromosphere, transition region, and corona with 0.33-0.4 ...arcsec spatial resolution, 2 s temporal resolution and 1 km/s velocity resolution over a field-of-view of up to 175 arcsec x 175 arcsec. IRIS was launched into a Sun-synchronous orbit on 27 June 2013 using a Pegasus-XL rocket and consists of a 19-cm UV telescope that feeds a slit-based dual-bandpass imaging spectrograph. IRIS obtains spectra in passbands from 1332-1358, 1389-1407 and 2783-2834 Angstrom including bright spectral lines formed in the chromosphere (Mg II h 2803 Angstrom and Mg II k 2796 Angstrom) and transition region (C II 1334/1335 Angstrom and Si IV 1394/1403 Angstrom). Slit-jaw images in four different passbands (C II 1330, Si IV 1400, Mg II k 2796 and Mg II wing 2830 Angstrom) can be taken simultaneously with spectral rasters that sample regions up to 130 arcsec x 175 arcsec at a variety of spatial samplings (from 0.33 arcsec and up). IRIS is sensitive to emission from plasma at temperatures between 5000 K and 10 MK and will advance our understanding of the flow of mass and energy through an interface region, formed by the chromosphere and transition region, between the photosphere and corona. This highly structured and dynamic region not only acts as the conduit of all mass and energy feeding into the corona and solar wind, it also requires an order of magnitude more energy to heat than the corona and solar wind combined. The IRIS investigation includes a strong numerical modeling component based on advanced radiative-MHD codes to facilitate interpretation of observations of this complex region. Approximately eight Gbytes of data (after compression) are acquired by IRIS each day and made available for unrestricted use within a few days of the observation.
This paper reports a novel dual-diode microwave rectifier with a microstrip access at 2.45 GHz. This circuit has been developed using a global analysis technique which associates electromagnetic and ...circuit approaches. Due to the differential topology of the rectifier, the input low-pass filter is not necessary. This makes the structure more compact. Two rectifiers with different Schottky diodes (HSMS 2860 and 2820) has been etched on Arlon 25N substrate and measured. Both rectifiers achieve an RF-to-dc conversion efficiency of 60% at 10 mW input power. A dc power more than 30 mW can be obtained with both rectifiers when the power density is 1 mW/cm 2 . The proposed circuits can be interconnected to form rectenna arrays. The parallel-connected array has been investigated. It was shown that by properly choosing the optimal load of the array, higher output dc power can be reached.
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