Alexandre François

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1 Introduction We present a system to perform real-time adaptive background modeling and segmentation of video streams. Our goal is to segment non background object silhouettes in video streams taken from a fixed camera. A number of systems performing segmentation of moving objects rely on image differencing, with various enhancements (e.g. [6]). A binary(More)
Whispering gallery modes (WGMs) in surface-fixated fluorescent polystyrene microbeads are studied in view of their capability of sensing the formation of biochemical adsorption layers on their outer surface with the well-established biotin-streptavidin specific binding as the model system. Three different methods for analysis of the observed shifts in the(More)
Building upon the model of Semantic Maps (Haspelmath 2003), which typologists have designed mainly for grammatical semantics, this chapter discusses methodological issues for a model in lexical typology. By breaking up polysemous lexemes of various languages into their semantic 'atoms' or senses, one defines an etic grid against which cross-linguistic(More)
Data collected on the 17 languages spoken in the Banks and Torres Islands (northern Vanuatu) reveal strikingly diverse vowel systems, differing both in the quality and the quantity of their phonemes. Except for Mota, which still perpetuates the ²ve vowels of Proto-Oceanic, the languages of this area have historically increased their inventories to as many(More)
The number of languages spoken on the planet has oscillated up and down throughout the history of mankind. 1 Different social factors operate in opposite ways, some resulting in the decrease of language diversity, others favouring the emergence of new languages. Thus, languages fade away and disappear when their speakers undergo some pressure towards(More)
Whispering gallery modes in surface-fixated fluorescent polystyrene microbeads are studied in view of their capability of sensing changes in the refractive index of the beads' environment by exposing them to water/glycerol mixtures of varying composition. The mode positions are analyzed by simultaneous fitting for mode number, bead radius, and environmental(More)
Acknowledgments I thank my advisor and chairman of my thesis committee, Prof. Gérard Medioni, for supporting and guiding me throughout my graduate studies at USC. Beyond the exceptional quality of his academic guidance, his most valuable gift to me was that of freedom, in all aspects of my life. Ghandeharizadeh, who served on my qualifying exam committee.(More)
Refractometric sensors based on optical excitation of surface plasmons on the side of an optical fiber is an established sensing architecture that has enabled laboratory demonstrations of cost effective portable devices for biological and chemical applications. Here we report a Surface Plasmon Resonance (SPR) configuration realized in an Exposed Core(More)