Search results for "Matching"
showing 10 items of 509 documents
Morphological Enhancement and Triangular Matching for Fingerprint Recognition
2008
Among the principal problems for realizing a robust Automated Fingerprint Identification System (AFIS) there are the images quality and matching algorithms. In this paper a fingerprint enhancement algorithm based on morphological filter and a triangular matching are introduced. The enhancement phase is based on tree steps: directional decomposition, morphological filter and composition. For the matching phase a global transformation to overcame the effects of rotation, displacement and deformation between acquired and stored fingerprint is performed using the number of similar triangular, having fingerprint minutiae as vertexes. The performance of the proposed approach has been evaluated on…
Second Harmonic Generation via Random Quasi-phase Matching in a Periodically Poled Lithium Tantalate Waveguide
2011
We observe second harmonic generation via random quasi phase matching in a 1.5μm periodically poled lithium tantalate. The presence of a slab waveguide allows the comparison between bulk and guided wave configurations.
Semi-automatic registration of retinal images based on line matching approach
2013
Accurate retinal image registration is essential to track the evolution of eye-related diseases. We propose a semiautomatic method based on features relying upon retinal graphs for temporal registration of retinal images. The features represent straight lines connecting vascular landmarks on the retina vascular tree: bifurcations, branchings, crossings, end points. In the built retinal graph, one straight line between two vascular landmarks indicates that they are connected by a vascular segment in the original retinal image. The locations of the landmarks are manually extracted to avoid the information loss due to errors in a retinal vessels segmentation algorithms. A straight line model i…
Exploiting the optical quadratic nonlinearity of zinc-blende semiconductors for guided-wave terahertz generation: A material comparison
2010
We present a detailed analysis and comparison of dielectric waveguides made of CdTe, GaP, GaAs and InP for modal phase matched optical difference frequency generation (DFG) in the terahertz domain. From the form of the DFG equations, we derived the definition of a very general figure of merit (FOM). In turn, this FOM enabled us to compare different configurations, by taking into account linear and nonlinear susceptibility dispersion, terahertz absorption, and a rigorous evaluation of the waveguide modes properties. The most efficient waveguides found with this procedure are predicted to approach the quantum efficiency limit with input optical power in the order of kWs.
<title>Restoration of a short-exposure image sequence degraded by atmospheric turbulence</title>
2000
This paper deals with the restoration of the shape of an object observed with a high-resolution infrared imaging device, through atmospheric turbulence. The propagation path is quite long (a few tenth kilometer) and the image is thus disturbed. A sequence of short-exposure images of the interesting object is recorded. We can see that the object shape fluctuates randomly during the sequence, but that its edges remain sharp, thanks to the very short exposure time. A bayesian analysis of the Fourier descriptors associated to the edges shows that the optimal shape is the one corresponding to the mean Fourier descriptors. We thus propose two ways to estimate this shape. The first one consists in…
Cloud motion detection from infrared satellite images
2002
The estimation of cloud motion from a sequence of satellite images can be considered a challenging task due to the complexity of phenomena implied. Being a non-rigid motion and implying non-linear events, most motion models are not suitable and new algorithms have to be developed. We propose a novel technique, combining a Block Matching Algorithm (BMA) and a best candidate block search along with a vector median regularisation.
A Community-based Approach for Service-based Application Composition in an Ecosystem
2010
The design of composite applications by combining existing services with known semantics is an ongoing topic in current research. Several studies are aimed at providing service description models and standards, service discovery and matching etc. However, service composition in distributed dynamic environments such as P2P ecosystems has received little attention from research communities. In this paper we present a design framework for composing services, taking in particular into account different ways of building peercommunities based on network or services characteristics.
Ontology-based service matching and discovery
2011
In this paper we consider ontologies as knowledge structures that specify attributes of services, their properties and relations among them to enable finding semantic similarity between service descriptions and service requests. Ontologies reflect semantic relationship between concepts represented by attributes in service descriptions and service requests. We use knowledge from ontologies to enhance the both user service requests and service descriptions by adding concepts that are not presented in the original descriptions, and use them in comparison process. It results in more precise matching since we consider also implicit concepts. Thus services and requests that do not contain exact m…
Joint Radio and Computational Resource Allocation in IoT Fog Computing
2018
The current cloud-based Internet-of-Things (IoT) model has revealed great potential in offering storage and computing services to the IoT users. Fog computing, as an emerging paradigm to complement the cloud computing platform, has been proposed to extend the IoT role to the edge of the network. With fog computing, service providers can exchange the control signals with the users for specific task requirements, and offload users’ delay-sensitive tasks directly to the widely distributed fog nodes at the network edge, and thus improving user experience. So far, most existing works have focused on either the radio or computational resource allocation in the fog computing. In this work, we inve…
Review of High Resolution Thermal Infrared Applications and Requirements: The Fuegosat Synthesis Study
2013
High resolution thermal infrared remote sensing can have a wide range of applications. In this chapter we describe the different applications and requirements identified after a revision study in the framework of the Fuegosat Synthesis Study (FSS). This project was funded by the European Space Agency (ESA), and the three main objectives were: (i) review of applications and analyses for user requirements, (ii) consolidation of user requirements over a broad range of applications, and (iii) matching of user requirements and industry concepts to identify and outline a set of potential mission scenarios and their corresponding requirements. This chapter focuses on issues (i) and (ii). These obj…