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241.
Mendez Oscar Hadfield Simon Pugeault Nicolas Bowden Richard 《International Journal of Computer Vision》2020,128(5):1286-1310
International Journal of Computer Vision - The use of human-level semantic information to aid robotic tasks has recently become an important area for both Computer Vision and Robotics. This has... 相似文献
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Impact of the spectral and spatial properties of natural light on indoor gas‐phase chemistry: Experimental and modeling study 下载免费PDF全文
M. Blocquet F. Guo M. Mendez M. Ward S. Coudert S. Batut C. Hecquet N. Blond C. Fittschen C. Schoemaecker 《Indoor air》2018,28(3):426-440
The characteristics of indoor light (intensity, spectral, spatial distribution) originating from outdoors have been studied using experimental and modeling tools. They are influenced by many parameters such as building location, meteorological conditions, and the type of window. They have a direct impact on indoor air quality through a change in chemical processes by varying the photolysis rates of indoor pollutants. Transmittances of different windows have been measured and exhibit different wavelength cutoffs, thus influencing the potential of different species to be photolysed. The spectral distribution of light entering indoors through the windows was measured under different conditions and was found to be weakly dependent on the time of day for indirect cloudy, direct sunshine, partly cloudy conditions contrary to the light intensity, in agreement with calculations of the transmittance as a function of the zenithal angle and the calculated outdoor spectral distribution. The same conclusion can be drawn concerning the position within the room. The impact of these light characteristics on the indoor chemistry has been studied using the INCA‐Indoor model by considering the variation in the photolysis rates of key indoor species. Depending on the conditions, photolysis processes can lead to a significant production of radicals and secondary species. 相似文献
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Assisted ventilation with pressure support (PSV) or proportional assist (PAV) ventilation has the potential to produce periodic breathing (PB) during sleep. We hypothesized that PB will develop when PSV level exceeds the product of spontaneous tidal volume (VT) and elastance (VTsp . E) but that the actual level at which PB will develop [PSV(PB)] will be influenced by the DeltaPCO2 (difference between eupneic PCO2 and CO2 apneic threshold) and by DeltaRR [response of respiratory rate (RR) to PSV]. We also wished to determine the PAV level at which PB develops to assess inherent ventilatory stability in normal subjects. Twelve normal subjects underwent polysomnography while connected to a PSV/PAV ventilator prototype. Level of assist with either mode was increased in small steps (2-5 min each) until PB developed or the subject awakened. End-tidal PCO2, VT, RR, and airway pressure (Paw) were continuously monitored, and the pressure generated by respiratory muscle (Pmus) was calculated. The pressure amplification factor (PAF) at the highest PAV level was calculated from [(DeltaPaw + Pmus)/Pmus], where DeltaPaw is peak Paw - continuous positive airway pressure. PB with central apneas developed in 11 of 12 subjects on PSV. DeltaPCO2 ranged from 1.5 to 5.8 Torr. Changes in RR with PSV were small and bidirectional (+1.1 to -3.5 min-1). With use of stepwise regression, PSV(PB) was significantly correlated with VTsp (P = 0.001), E (P = 0.00009), DeltaPCO2 (P = 0.007), and DeltaRR (P = 0.006). The final regression model was as follows: PSV(PB) = 11.1 VTsp + 0.3E - 0.4 DeltaPCO2 - 0.34 DeltaRR - 3.4 (r = 0.98). PB developed in five subjects on PAV at amplification factors of 1.5-3.4. It failed to occur in seven subjects, despite PAF of up to 7.6. We conclude that 1) a PCO2 apneic threshold exists during sleep at 1.5-5.8 Torr below eupneic PCO2, 2) the development of PB during PSV is entirely predictable during sleep, and 3) the inherent susceptibility to PB varies considerably among normal subjects. 相似文献
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E da C da Fonseca Lopes S C Derivi M H Mendez 《Archivos latinoamericanos de nutrición》1986,36(2):282-287
A retrospective study was carried out on the type of habitual diet consumed in the Niterói (Rio de Janeiro) city. Two groups of subjects were integrated: the Experimental Group, formed by patients with neoplasms of the large intestine and rectum, and the Control Group, formed by individuals with no gastrointestinal disorders. The information obtained through direct inquiry, strongly suggests that cancer of the colon and rectum may be related to the high proportion of fat and low proportion of dietary fiber found in the diets of the patients studied. 相似文献
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Objects identification and localization and more generally scene analysis, need a preliminary step of edge detection. Because of the very important amount of data to be processed, implementing any edge detection algorithm on a conventional computer leads to a high computational cost, too high for many applications: in robotics for instance. The authors present here an on-line real time processor which works upon the digitized signal of a TV camera. This processor computes the two components of the gradient associated with each pixel, using a Sobel operator. Then it selects edge pixels on the basis of informations about the gradient in the neighbourhood of each pixel. The processed image appears synchronously with the video signal, delayed by a 2 TV lines duration compared to the original image. 相似文献
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