Search results for " Programming"

Extraction of objects from structured backgrounds in the cat superior colliculus. Part II

1980

Specific changes occur in the cells of the uppers layers of the cat's superior colliculus when a two dimensional noise (background) is superimposed onto a deterministic signal (spot of light). Some of the measurements can be interpreted as meaning that some cells only react to certain relative movements of object (spot) and background (noise). The movement of the visual background is interpreted as environmental movement occurring due to the animal's own movement. The results of the measurements provide all the necessary presuppositions for a distinction between the animal's own velocity and that of the object (Part I). The experimental results can be interpreted with a model. The essential…

Optimization of Complex SVM Kernels Using a Hybrid Algorithm Based on Wasp Behaviour

2010

The aim of this paper is to present a new method for optimization of SVM multiple kernels The kernel substitution can be used to define many other types of learning machines distinct from SVMs We introduced a new hybrid method which uses in the first level an evolutionary algorithm based on wasp behaviour and on the co-mutation operator LR−Mijn and in the second level a SVM algorithm which computes the quality of chromosomes The most important details of our algorithms are presented The testing and validation proves that multiple kernels obtained using our genetic approach are improving the classification accuracy up to 94.12% for the “leukemia” data set.

2014

For locating inaccurate problem of the discrete localization criterion proposed by Demigny, a new criterion expression of “good localization” is proposed. Firstly, a discrete expression of good detection and good localization criterion of two dimension edge detection operator is employed, and then an experiment to measure optimal parameters of two dimension Canny's edge detection operator is introduced after. Moreover, a detailed performance comparison and analysis of two dimension optimal filter obtained via utilizing tensor product for one dimension optimal filter are provided which can prove that least square support vector regression (LS-SVR) is a smoothness filter and give the construc…

An architecture for automatic gesture analysis

2000

The field of human-computer interaction has been widely investigated in the last years, resulting in a variety of systems used in different application fields like virtual reality simulation environments, software user interfaces, and digital library systems.A very crucial part of all these systems is the input module which is devoted to recognize the human operator in terms of tracking and/or recognition of human face, arms position, hand gestures, and so on.In this work a software architecture is presented, for the automatic recognition of human arms poses. Our research has been carried on in the robotics framework. A mobile robot that has to find its path to the goal in a partially struc…

Analogy Construction and Success in Mathematics and Science Problem-solving: a Study with Secondary Students // Construcción de analogías y éxito en …

2012

We conducted an empirical study to analyse the association between students’ perception of surface and structural analogies between problems, and their algebraic success. Different surface and structural relationships between one ‘source’ problem and ‘target’ problems were considered. We also considered high (daily life) and low (scientific) familiarity contexts. Algebraic success was measured by the equations selected to solve each problem. Similarities and differences between problems were explicitly asked to students. Results showed a significant correlation between detecting the correct structural relation between problems and selecting the correct equations to solve them. Low familiari…

Multiresolution Analysis for Meshes with Appearance Attributes

2005

International audience; We present a new multiresolution analysis framework for irregular meshes with attributes based on the lifting scheme. We introduce a surface prediction operator to compute the detail coefficients for the geometry and the attributes of the model. Attribute analysis gives appearance information to complete the geometrical analysis of the model. A set of experimental results are given to show the efficiency of our framework. We present two applications to adaptive visual-ization and denoising.

Thermodynamics of Nanoparticles: Experimental Protocol Based on a Comprehensive Ginzburg-Landau Interpretation

2014

MATERIAUX+SMR:SDA; The effects of surface and interface on the thermodynamics of small particles require a deeper understanding. This step is crucial for the development of models that can be used for decision-making support to design nanomaterials with original properties. On the basis of experimental results for phase transitions in compressed ZnO nanoparticles, we show the limitations of classical thermodynamics approaches (Gibbs and Landau). We develop a new model based on the Ginzburg-Landau theory that requires the consideration of several terms, such as the interaction between nanoparticles, pressure gradients, defect density, and so on. This phenomenological approach sheds light on …

Near-surface defect profiling with slow positrons: Argon-sputtered Al(110).

1985

We report on slow-positron measurements of atomic defect distribution near a solid surface. Defects are produced by argon-ion bombardment of an Al(110) surface in ultrahigh vacuum. Defect profiles have a typical width of 15–25 Å and contain a broader tail extending to 50–100 Å. The defect density at the outermost atomic layers saturates at high argon fluences to a few atomic percent, depending on sputtering conditions. Defect production rate at >1 keV Ar+ energies is typically 1–5 vacancy-interstitial pairs per incident ion. Molecular-dynamics simulations of the collision cascade predict similar defect distributions. Peer reviewed

Multiresolution Analysis for Irregular Meshes

2003

International audience; The concept of multiresolution analysis applied to irregular meshes has become more and more important. Previous contributions proposed a variety of methods using simplification and/or subdivision algorithms to build a mesh pyramid. In this paper, we propose a multiresolution analysis framework for irregular meshes with attributes. Our framework is based on simplification and subdivision algorithms to build a mesh pyramid. We introduce a surface relaxation operator that allows to build a non-uniform subdivision for a low computational cost. Furthermore, we generalize the relaxationoperator to attributes such as color, texture, temperature, etc. The attribute analysis…

The range of non-surjective convolution operators on Beurling spaces

1996

AbstractLet μ ≠ 0 be an ultradistribution of Beurling type with compact support in the space . We investigate the range of the convolution operator Tμ on the space of non-quasianalytic functions of Beurling type associated with a weight w, in the case the operator is not surjective. It is proved that the range of TM always contains the space of real-analytic functions, and that it contains a smaller space of Beurling type for a weight σ ≥ ω if and only if the convolution operator is surjective on the smaller class.