摘要 :
A News video can be modeled using the stratification approach by identifying, among other entities, human faces appearing in the video stream. To facilitate this, we need to develop techniques to detect and track hu- man faces in ...
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A News video can be modeled using the stratification approach by identifying, among other entities, human faces appearing in the video stream. To facilitate this, we need to develop techniques to detect and track hu- man faces in video. This paper presents a frontal face detection method that uses the gradient energy rep- resentation extracted directly from the MPEG video. The gradient energy representation permits pertinent Facial features of high contrast, such as the eyes, nose And mouth, to be highlighted.
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摘要 :
ADEUN (ADaptive rEUable traNsport) protocol is a reliable transport protocol only based on FEC (Forward Error Correction) for UASN (Underwater Acoustic Sensor Networks). In cooperative scenario, ADEUN improves its reliability of d...
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ADEUN (ADaptive rEUable traNsport) protocol is a reliable transport protocol only based on FEC (Forward Error Correction) for UASN (Underwater Acoustic Sensor Networks). In cooperative scenario, ADEUN improves its reliability of data packet transmission further by forwarding node redundancy, which wastes the limited energy and bandwidth of nodes. In this paper, the IPool-ADELIN protocol is proposed and shown to help reduce energy consumption. In IPool-ADELIN, by overhearing the data transmissions, the IPool node not only relays the data packets, which are not implicitly acknowledged, but also does local link maintenance when the BER (Bit Error Rate) of the monitored link is high. The results of mathematical analysis and simulations show that IPool-ADELIN has a higher data delivery ratio and lower energy consumption.
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摘要 :
Cyanobacterial blooms are becoming potent agents of natural selection in aquatic ecosystems because of their high production of some toxins and increased frequency in recent decades with eutrophication and climate change. Maternal...
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Cyanobacterial blooms are becoming potent agents of natural selection in aquatic ecosystems because of their high production of some toxins and increased frequency in recent decades with eutrophication and climate change. Maternal exposure to the toxic Microcystis aeruginosa significantly increased the intrinsic rates of population increase, average life span, and net reproductive rates of a clone of the planktonic grazer Daphnia carinata in an offspring environment where cyanobacteria were present, but not for two additional clones. Offspring from mothers exposed to M. aeruginosa had lower intrinsic rates of population increase, average life span, and net reproductive rates than individuals from unexposed mothers when fed exclusively a green alga. These results suggest that benefits, costs, and clonal variations of maternal effects of inducible tolerance should be considered when trying to understand ecological consequences of cyanobacterial blooms since they can shape the trophic interactions between cyanobacteria and daphnids.
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