منابع مشابه
Active Optics and Coronography with the Hubble Space Telescope
In the eld of planet and proto-planetary disk detection, achieving high angular resolution and high dynamic range is a necessity. Ground images are blurred by atmospheric turbulence and therefore adaptive optics is necessary to achieve sub-arcsecond images. Coronography coupled with adaptive optics on ground-based telescopes is a way to get both good spatial resolution and high dynamic range. H...
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Introduction: Various surgical approaches to parapharyngeal space (PPS) tumors are introduced to obtain complete removal with the preservation of the surrounding structures in parapharyngealneoplasms. Here, we will discuss the main techniques and their outcome. Materials and Methods: This retrospective study was conducted on 78 patients undergone either transoral, tran...
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The simultaneous need for a wide angle of eld and high resolution has led to the use of spatially variant sensors in active vision systems. The use of such sensors however necessitates the existence of gaze control mechanisms for guiding the foveal high resolution region of the sensor to points of interest in the visual world. While bottom-up alerting cues such as motion have previously been us...
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ژورنال
عنوان ژورنال: Nature
سال: 1993
ISSN: 0028-0836,1476-4687
DOI: 10.1038/361008a0