Search results for "Method"
showing 10 items of 13253 documents
A Continuous Time Pattern Recognition Retina
2002
International audience; We present in this paper a pattern recognition retina operating in continuous time. During a programming phase, the reference image is acquired by the sensor. After thresholding, the resulting binary image is stored in the sensor's pixels. During the recognition phase, the retina calculates, in an analog way and in continuous time, the zero displacement intercorrelation of the current image with the binary reference image and its complement. These two intercorrelation values are output as currents. By comparing these currents to expected values, determined during the programming phase, a shift of the pattern or a difference between the observed and programmed pattern…
Surface plasmon interference excited by tightly focused laser beams
2007
International audience; We show that interfering surface plasmon polaritons can be excited with a focused laser beam at normal incidence to a plane metal film. No protrusions or holes are needed in this excitation scheme. Depending on the axial position of the focus, the intensity distribution on the metal surface is either dominated by interferences between counterpropagating plasmons or by a two-lobe pattern characteristic of localized surface plasmon excitation. Our experiments can be accurately explained by use of the angular spectrum representation and provide a simple means for locally exciting standing surface plasmon polaritons.
Optimal Gabor Filters and Haralick Features for Industrial Polarization Imaging
2011
International audience; During the past decade, computer vision methods for inline inspection became an important tool in a lot of industrial processes. During the same time polarization imaging techniques rapidly evolved with the development of electro-optic components, as e.g. the polarization cameras, now available on the market. This paper is dedicated to the application of polarization techniques for visually inspecting complex metallic surfaces. As we will shortly recall, this consists of a direct image interpretation based on the measurement of the polarization parameters of the light reflected by the inspected object. The proposed image interpretation procedure consists of a Gabor p…
Hyperspectral near-field imaging : development and applications to nanophotonics devices
2013
The scanning near-field optical microscopy (SNOM) is used to analyze optical phenomena at the sub-wavelength scale such as light localization and propagation in photonic crystals or plasmonic devices. In any case, SNOM experiments rely on the positioning of a local probe in the optical near field of a given structure and on the detection of the surrounding evanescent waves. Depending on the nature of the probe or on the optical detection method, the detected physical properties are the spatial distributions of the amplitude and phase or the intensity of the electric and magnetic components of the probed field. We present here the implementation of an innovative hyperspectral near-field imag…
Improving IoT Communications Based on Smart Routing Algorithms
2018
International audience; Due to the recorded success by Internet of Things (IoT) technology, more and more domains use it as a communications and exchange network such as e-health, smart cities, vehicles, etc. IoT don’t stop integrating an important number of components and objects that are characterized by their complexity and heterogeneity. Such constraints make the existing routings protocols unsuitable for IoT communications. To accomplish all the expected tasks and satisfy the user services, it is important to guarantee a quality of communication that answers to the requirements of the various applications in terms of data and processing (availability, integrity, efficiency, etc.). The …
Geometric optimal control : homotopic methods and applications
2012
This work is about geometric optimal control applied to celestial and quantum mechanics. We first dealt with the minimum fuel consumption problem of transfering a satellite around the Earth. This brought to the creation of the code HamPath which permits first of all to solve optimal control problem for which the command law is smooth. It is based on the Pontryagin Maximum Principle (PMP) and on the notion of conjugate point. This program combines shooting method, differential homotopic methods and tools to compute second order optimality conditions. Then we are interested in quantum control. We study first a system which consists in two different particles of spin 1/2 having two different r…
Context-Aware Model Applied to Hog Descriptor for People Detection
2018
International audience; This work proposes and implements a method based on Context-Aware Visual Attention Model (CAVAM), but modifying the method in such way that the detection algorithm is replaced by Histograms of Oriented Gradients (HOG). After reviewing different algorithms for people detection, we select HOG method because it is a very well known algorithm, which is used as a reference in virtually all current research studies about automatic detection. In addition, it produces accurate results in significantly less time than many algorithms. In this way, we show that CAVAM model can be adapted to other methods for object detection besides Scale-Invariant Feature Transform (SIFT), as …
Multi-Scale Feature Extraction for Vehicle Detection Using Phis-Lbp
2018
International audience; Multi-resolutionobjectdetectionfacesseveraldrawbacksincludingitshighdimensionalityproducedby a richer image representation in different channels or scales. In this paper, we propose a robust and lightweight multi-resolution method for vehicle detection using local binary patterns (LBP) as channel feature. Algorithm acceleration is done using LBP histograms instead of multi-scale feature maps and by extrapolating nearby scales to avoid computing each scale. We produce a feature descriptor capable of reaching a similar precision to other computationally more complex algorithms but reducing its size from 10 to 800 times. Finally, experiments show that our method can obt…
Structure and determinants of production in Textile-Clothing-Leather-Skins (TCLS) craft industry in Benin: a study based on investigations of the val…
2014
Lieu et date de la conférence modifiées. Prétoria 31Juillet au 2 Août 2014 (Au lieu de Kigali -Rwanda); International audience; Sustainable economic growth in Benin requires a better understand of the informalsector, which contributes to two-thirds of GDP. Particularly, craft industry and TCLSsubsector is one of informal activity sector to be handled. The objectives of this work wereto identify the structure and factors that determine the production in TCLS craft industry.This study was based on a survey carried out in February 2011 on value creationdata in craft industry of TCLS in Benin. Lack of data induced by informal activities wascircumvented using an imputation method. A Multiple Cor…
Comparaison de différents plans de sondage et construction de bandes de confiance pour l'estimation de la moyenne de données fonctionnelles : une ill…
2012
Accepté pour publication dans Survey Methodology/Techniques d'Enquêtes.; Lorsque les variables étudiées sont fonctionnelles et que les capacités de stockage sont limitées ou que les coûts de transmission sont élevés, les sondages, qui permettent de sélectionner une partie des observations de la population, sont des alternatives intéressantes aux techniques de compression du signal. Notre étude est motivée, dans ce contexte fonctionnel, par l'estimation de la courbe de charge électrique moyenne sur une période d'une semaine. Nous comparons différentes stratégies d'estimation permettant de prendre en compte une information auxiliaire telle que la consommation totale de la période précédente. …