Search results for "interpolation."
showing 10 items of 253 documents
Parameters identification of the complex impedance model of the PEM fuel cell using Matlab/Simulink
2017
In this work, we present a new technical method for identifying the complex impedance model parameters of a Proton Exchange Membrane (pEM) Fuel Cell for on-board diagnosis in real time. The study of the PEM Fuel Cell modelling is important in order to understand the physical phenomena that occurring in this green renewable energy source. A diagnosis method is presented by analyzing the behavior of the complex impedance. For this, we present the identification method of the various complex impedance parameters; this identification is based on mathematical methods using the least squares method and the interpolation analysis method. The results are obtained using Matlab/Simulink tools and all…
Application of cohesive-zone models to delamination behaviour of composite material
2012
International audience; The parameters of cohesive elements have to be chosen correctly in the simulation of composite delamination by finite element method: such as interface strength, interface stiffness and shape of cohesive law. The purpose of this work is to investigate their influence on the accuracy of the results obtained. A three-dimensional cohesive-zone model has been established using Ls-dyna to simulate Double-Cantilever-Beam mode I (DCB) and Edge-Notched-Flexure mode II (ENF) tests. The influence of these parameters of cohesive element on the maximum load and the slope of load-displacement curve have been discussed by comparing experimental and numerical results. Four traction…
Characterizations of convex approximate subdifferential calculus in Banach spaces
2016
International audience; We establish subdifferential calculus rules for the sum of convex functions defined on normed spaces. This is achieved by means of a condition relying on the continuity behaviour of the inf-convolution of their corresponding conjugates, with respect to any given topology intermediate between the norm and the weak* topologies on the dual space. Such a condition turns out to also be necessary in Banach spaces. These results extend both the classical formulas by Hiriart-Urruty and Phelps and by Thibault.
Interpolation by local information
2008
Les méthodes d'interpolation, qu'elles procèdent de régressions ou de krigeage, sont globales, en ce sens qu'elles utilisent l'ensemble des données disponibles sur un territoire donné. Or, quand l'hétérogénéité spatiale de celui-ci est forte, la qualité des résultats s'en ressent. Pour dépasser cette difficulté, une méthode d'interpolation locale est proposée et appliquée, à titre de test, aux températures du territoire français. Partant d'un jeu de stations de mesures réparties sur cet espace digitalisé à 250 m, la méthode consiste à modéliser les variations spatiales locales de la température en considérant chaque point de la grille et les n stations voisines les plus proches qui l'entour…
La antike Rechtsgeschichte, la Interpolationenforschung e una lettera inedita di Koschaker a Riccobono
2011
An unpublished letter contributes to delineate the relationship between Paul Koschaker and Salvatore Riccobono with particular attention to the discussion about the so-called 'antike Rechtsgeschichte'.
Gradenwitz, Riccobono und die Entwicklung der Interpolationenkritik. Methodentransfer unter europäischen Juristen im späten 19. Jahrhundert / Gradenw…
2018
Die interpolationistische Methode der Untersuchung römischer Rechtstexte, also deren Wahrnehmung als Ergebnis von nachträglichen Eingri4en, ist Gegenstand eines wiedererwachten Interesses der romanistischen Forschung. Ihre intensivste Phase erlebte die Interpolationenforschung am Ende des 19. und in den ersten Jahrzehnten des 20. Jahrhunderts. Das heutige Verstehensinteresse richtet sich insbesondere auf die Verflechtung der interpolationistischen Methode mit anderen Forschungsansätzen sowie auf ihre Entwicklung, die auf dem Gedankenaustausch zwischen Wissenschaftlern in Italien, Deutschland und anderen Ländern basiert. Im Zentrum der hier versammelten Arbeiten stehen Otto Gradenwitz, der B…
Evaluation of interpolation methods for TG-43 dosimetric parameters based on comparison with Monte Carlo data for high-energy brachytherapy sources.
2010
Purpose The aim of this work was to determine dose distributions for high-energy brachytherapy sources at spatial locations not included in the radial dose function gL(r) and 2D anisotropy function F(r,θ) table entries for radial distance r and polar angle θ. The objectives of this study are as follows: 1) to evaluate interpolation methods in order to accurately derive gL(r) and F(r,θ) from the reported data; 2) to determine the minimum number of entries in gL(r) and F(r,θ) that allow reproduction of dose distributions with sufficient accuracy. Material and methods Four high-energy photon-emitting brachytherapy sources were studied: 60Co model Co0.A86, 137Cs model CSM-3, 192Ir model Ir2.A85…
Scratch detection and removal from static images using simple statistics and genetic algorithms
2002
This paper investigates the removal of line scratches from old movies and gives a twofold contribution. First, it presents simple technique for detecting the scratches, based on an analysis of the statistics of the grey levels. Second, the scratch removal is approached as an optimisation problem, and it is solved by using a genetic algorithm. The method can be classified as a static approach, as it works independently on each single frame of the sequence. It does not require any a-priori knowledge of the absolute position of the scratch, nor an external starting population of chromosomes for the genetic algorithm. The central column of the line scratch once detected is changed with a conven…
Poincaré Type Inequalities for Vector Functions with Zero Mean Normal Traces on the Boundary and Applications to Interpolation Methods
2019
We consider inequalities of the Poincaré–Steklov type for subspaces of H1 -functions defined in a bounded domain Ω∈Rd with Lipschitz boundary ∂Ω . For scalar valued functions, the subspaces are defined by zero mean condition on ∂Ω or on a part of ∂Ω having positive d−1 measure. For vector valued functions, zero mean conditions are applied to normal components on plane faces of ∂Ω (or to averaged normal components on curvilinear faces). We find explicit and simply computable bounds of constants in the respective Poincaré type inequalities for domains typically used in finite element methods (triangles, quadrilaterals, tetrahedrons, prisms, pyramids, and domains composed of them). The second …
An efficient grid-based RF fingerprint positioning algorithm for user location estimation in heterogeneous small cell networks
2014
This paper proposes a novel technique to enhance the performance of grid-based Radio Frequency (RF) fingerprint position estimation framework. First enhancement is an introduction of two overlapping grids of training signatures. As the second enhancement, the location of the testing signature is estimated to be a weighted geometric center of a set of nearest grid units whereas in a traditional grid-based RF fingerprinting only the center point of the nearest grid unit is used for determining the user location. By using the weighting-based location estimation, the accuracy of the location estimation can be improved. The performance evaluation of the enhanced RF fingerprinting algorithm was c…