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81.
A video database of moving faces and people   总被引:3,自引:0,他引:3  
We describe a database of static images and video clips of human faces and people that is useful for testing algorithms for face and person recognition, head/eye tracking, and computer graphics modeling of natural human motions. For each person there are nine static "facial mug shots" and a series of video streams. The videos include a "moving facial mug shot," a facial speech clip, one or more dynamic facial expression clips, two gait videos, and a conversation video taken at a moderate distance from the camera. Complete data sets are available for 284 subjects and duplicate data sets, taken subsequent to the original set, are available for 229 subjects.  相似文献   
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Résumé On propose une étude expérimentale du comportement d'un enrobé bitumineux. L'appareillage utilisé, qui est rapidement décrit, permet d'effectuer des essais triaxiaux de révolution régulés en température. Les résultats confirment que le comportement de ce matériau, qui comprend une composante visqueuse très marquée, est qualitativement le même pour les différentes valuers des variables de sollicitation: vitesse de déformation axiale, température et pression de confinement. Différents paramètres mécaniques ont été analysés. On précise l'évolution de ces paramètres, au nombre de 11, en fonction des variables de sollicitation A partir des résultats présentés et de ceux obtenus lors de campagnes d'essais antérieures, on propose un critère de contrainte maximale (appelée généralement contrainte de rupture). L'obtention d'un tel critère, pour les enrobés bitumineux, est nouveau.
Summary An experimental study of the behaviour of bituminous mixes is presented. The tests were performed using a triaxial apparatus, with temperature regulation, developed in our laboratory. First, two classes of cyclic stress path are analysed. The evolution of 11 mechanical parameters characterizing modulus, particular stresses, and volume variations which are obtained from the experimental data are linked with the chosen variables: temperature, confining pressure and rate of the axial strain. These variables are kept constant during each test. The reaction of the material is different for each value of the selected variable and the shape of the curves is the same as that obtained for non-cohesive granular materials. We observe, in particular, during compression, a contraction phase followed by an increase in the volume of the sample. The effects of the strain rate show the viscous behaviour of this kind of material. The values of the maximum stress are also studied. Following two realistic hypotheses, a maximum stress criterion (generally called the failure stress criterion) is given. The first hypothesis is linked with the conical shape of the governing formulation. It appears as a 3D extrapolation of our experimental data. The second hypothesis assumes that the material is isotropic. It was verified experimentally for compression and extension tests, on sample cubes in various directions. These tests show a slight anisotropy, which is neglected. Nevertheless, a method is given to take it into account, considering rotation of the cone. The criterion developed involves two cones, each with the trisectrix as axis and of equilateral triangular section extending into the principal stress space. The first cone arises when the stresses are positive (compression), and the second one when at least on stress is negative. The intersection of the two cones is on the coordinate planes. For a given temperature, this formulation contains five constants, and three of them define the strain rate effect. Such a criterion is, to the best of our knowledge, new.
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85.
Attempts to improve the efficacy of pretransplant conditioning regimens have been published, the potential of a better antileukemic effect being impaired by more frequent and severe toxicities. The efficacy of an intensified regimen, TAM (TBI, high-dose cytosine arabinoside and melphalan), is evaluated by analyzing long-term follow-up of a homogenous group of 42 high-risk ALL patients allografted in first CR. Age at time of BMT was 25.9 +/- 10.4 years (3-41). Twenty-two patients had more than three adverse prognostic factors. Ten patients had a Ph chromosome. Probability of overall survival was 45 +/- 9%, and for all surviving patients median follow-up time was 66 months. Event-free survival was 40 +/- 8% at 7 years after transplantation and the expected relapse rate reached 31%. Twenty-two deaths occurred, six after a relapse but 16 appeared to be directly due to the BMT procedure. None of the pretransplant characteristics significantly affected outcome after BMT. TAM appeared to be an efficient antileukemic therapy for conditioning high-risk ALL patients before allogeneic transplantation, but was still very toxic. The use of TAM in adult ALL patients in first CR is not recommended and the real role of intensified conditioning regimens remains to be demonstrated.  相似文献   
86.
Objective: The purpose of this study was to compare the signal-to-noise ratio (SNR) of phantom and rat brain images performed at 1.5 T on a clinical MR system and at 7 T on a small-animal experimental system. Comparison was carried out by taking into account SNR values based on a single sample acquisition at 1.5 and 7 T as well as on simultaneous imaging of multiple samples at 1.5 T. Methods: SNR was experimentally assessed on a phantom and rat brains at 1.5 and 7 T using 25 mm surface coils and compared to theoretical SNR gain estimations. The feasibility of multiple-animal imaging, using the hardware capabilities available on the 1.5 T system, was demonstrated. Finally, rat brain images obtained on a single animal at 7 T and on multiple animals acquired simultaneously at 1.5 T were compared. Results: Experimentally determined SNR at 7 T was far below theoretical estimations. Taking into account chemical shift, susceptibility artifacts and modifications of T1 and T2 relaxation times at higher field, a 7-T system holds limited advantage over a 1.5-T system. Instead, a multiple-animal acquisition methodology was demonstrated on a clinical 1.5-T scanner. This acquisition method significantly increases imaging efficiency and competes with single animal acquisitions at higher field. Conclusion: Multiple-animal imaging using a standard clinical scanner has a great potential as a high-throughput acquisition method for small animals.  相似文献   
87.
EPR dose reconstruction after accidental photon exposure based on materials irradiated in the vicinity of the victim (sucrose, medicine tablets, etc.) was used successfully in several cases referenced in the literature. However, accidental exposure may also occur with a neutron component such as in the Tokai-Mura criticality accident. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials already used for photon exposure (sucrose) or with potential dosimetric properties (ascorbic acid, sorbitol, glucose, galactose, fructose, lactose and mannose). To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of an experimental reactor with different neutron to photon ratios. The relative neutron sensitivity was found to range from 12 to 43% according to the materials. The potentiality of these materials for mixed field EPR dosimetry is discussed.  相似文献   
88.
Feeding vegetable oils rich in linoleic acid has been demonstrated to be an effective strategy to enrich milk with conjugated linoleic acid (CLA). However, high amounts of vegetable oil in the diet in free form could adversely affect animal performance, mainly in sheep. The aim of this work was to improve the ewe milk fatty acid profile by increasing potentially healthy acids such as CLA without any detrimental effects on milk production and ruminal fermentation with soybean oil (SBO) diet supplementation. Twenty-four ewes were assigned to 2 treatments and fed 2 diets (control or supplemented with 6% of SBO; 2 lots of 6 animals per treatment) and fed ad libitum for 4 wk. The forage:concentrate ratio was 20:80. Batch cultures of rumen microorganisms were used to study in vitro rumen fermentation. Changes in fatty acid profile were characterized as a reduction in C6:0 to C16:0 at the expense of an increase in C18:0, C18:1 isomers, and CLA concentrations. Proportions of milk CLA and trans-11 C18:1 (vaccenic acid) went from 1.04 to 3.44 and 2.08 to 6.20 g/100 g of total fatty acids, respectively. However, the SBO diet also increased trans-10 C18:1 and other trans C18:1 content. No significant decreases were found in the treatments for dry matter intake and milk production. The notable increases in trans-10, cis-12 and trans-9, cis-11 were not accompanied by fat level decreases in ewe milk. Concerning in vitro ruminal fermentation, no significant differences were found in the extent and rate of gas production, effective degradability, in vitro true digestibility, and volatile fatty acid production. The results demonstrate that dairy sheep milk CLA content can be substantially increased (more than 3-fold) by adding high levels of SBO in the diet as free oil, without any negative effects on animal performance.  相似文献   
89.
We study the diffusive interaction between soda-lime glass substrates and sputtered aluminum-doped silica thin films at 650°C, the temperature of commercial soda-lime glass shaping or tempering. A first rapid migration of alkali ions from substrate to thin film has been described in a companion paper (J Am Ceram Soc. 2018;101:1516). Using the same samples as (J Am Ceram Soc. 2018;101:1516), we focus here on later interactions, when the layer is consumed by the substrate resulting from diffusive interactions. Using Secondary Ion Mass Spectroscopy profilometry, we show that the interdiffusion rate increases with the aluminum doping content of the layer. We show that the alkali uptake of silica layers accelerates diffusive exchanges with the substrate, consistently with a decrease of viscosity of the layer. Diffusion profiles of silicon are well reproduced when solving the diffusion equation for a diffusivity having an exponential dependence with silicon concentration. The diffusivity of aluminum is shown to be 10 times slower than the diffusion of silicon. Specific exchanges of the two network formers with network modifiers are deduced from the composition-space trajectories, providing evidence for multicomponent diffusive couplings between species.  相似文献   
90.
While it is known that resorcinol- and phenol-type aromatic structures within natural organic matter (NOM) react during drinking water chlorination to form trihalomethanes (THMs), limited studies have examined aliphatic-type structures as THM and haloacetic acid (HAA) precursors. A suite of aliphatic acid model compounds were chlorinated and brominated separately in controlled laboratory-scale batch experiments. Four and two beta-dicarbonyl acid compounds were found to be important precursors for the formation of THMs (chloroform and bromoform (71-91% mol/mol)), and dihaloacetic acids (DXAAs) (dichloroacetic acid and dibromoacetic acid (5-68% mol/mol)), respectively, after 24 h at pH 8. Based upon adsorbable organic halide formation, THMs and DXAAs, and to a lesser extent mono and trihaloacetic acids, were the majority (> 80%) of the byproducts produced for most of the aliphatic beta-dicarbonyl acid compounds. Aliphatic beta-diketone-acid-type and beta-keto-acid-type structures could be possible fast- and slow-reacting THM precursors, respectively, and aliphatic beta-keto-acid-type structures are possible slow-reacting DXAA precursors. Aliphatic beta-dicarbonyl acid moieties in natural organic matter, particularly in the hydrophilic fraction, could contribute to the significant formation of THMs and DXAAs observed after chlorination of natural waters.  相似文献   
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