45 research outputs found
Measurements and analysis of acoustic backscattering by elastic cubes and irregular polyhedra
Analytical methods for inferring functional effects of single base pair substitutions in human cancers
Cancer is a genetic disease that results from a variety of genomic alterations. Identification of some of these causal genetic events has enabled the development of targeted therapeutics and spurred efforts to discover the key genes that drive cancer formation. Rapidly improving sequencing and genotyping technology continues to generate increasingly large datasets that require analytical methods to identify functional alterations that deserve additional investigation. This review examines statistical and computational approaches for the identification of functional changes among sets of single-nucleotide substitutions. Frequency-based methods identify the most highly mutated genes in large-scale cancer sequencing efforts while bioinformatics approaches are effective for independent evaluation of both non-synonymous mutations and polymorphisms. We also review current knowledge and tools that can be utilized for analysis of alterations in non-protein-coding genomic sequence
Lower detection limit of the acousto-optic effect using Optical Feedback Interferometry
International audienceMeasurement and 3D imaging of acoustic waves through the acousto-optic effect has recently been demonstrated by means of Optical Feedback Interferometry (OFI). In this paper we study experimentally the lower limits of detection of an acoustic wave using an OFI sensor. We show that the OFI sensor exhibits a linear response to acoustic power variations, and we obtain a lower limit of detection of 83 dB rms for a planar acoustic wave at 3 kHz. We also determine the equivalent displacement, that is seen by the OFI sensor at this pressure level, to be 96 pm. A deeper understanding of the limits of the technology and the quantification of the acousto-optic effect shall help improve the applications already created for the measurement of acoustic pressure waves using OFI
Experimental Demonstration of the Impact of theFringe Shape in Sub-Lambda / 2 Sensing With OpticalFeedback Interferometry
International audienceIt is established in the Optical Feedback Interferometry (OFI) theory that the shape of the interferometric fringe has an impact on the detector's response to very small displacement measurements. In this paper we validate-for the first time based on experimental results-this statement by comparing experiments to an established model implementation. Through these experiments we show that the amplitude of the signals induced by sub-lambda/2 optical path variations is linearly dependent on the slope of the underlying fringe. Thus, careful control of the phase allows us to maximize the detection amplitude of very small displacements by positioning the phase where the fringe slope is the steepest. These results are directly applicable to established OFI applications that measure sub-lambda/2 optical path variations, such as OFI vibrometers or acoustic imaging though the acousto-optic effect
Preliminary investigation on the detection of slow-growing cracks in vibrating structures
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Filtering-based Analysis Comparing the DFA with the CDFA for Wide Sense Stationary Processes
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Interpréter les Fonctions de Fluctuation du DFA et du DMA comme le Résultat d'un Filtrage
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