Search results for "QUANTIFICATION"
showing 10 items of 157 documents
Herramientas matemáticas multi-escala para el tratamiento de señales
2019
En aquesta tesi doctoral, presentada com a compendi d'articles, es desenvolupen diverses eines matemàtiques per a processar senyals procedents de problemes reals. Aquestes tècniques estan basades en la teoria de la multi-resolució de Harten i la teoria d'esquemes de subdivisió. En aquest compendi es recullen treballs de disseny de nous esquemes de subdivisió no-lineals i aplicacions en Química Analítica, en optimització i en el disseny de velers de competició, entre d'altres. In this doctoral thesis, presented as a compendium of articles, various mathematical tools are developed to process signals from real problems. These techniques are based on Harten's multi-resolution framework and subd…
High-accuracy approximation of piecewise smooth functions using the Truncation and Encode approach
2017
Abstract In the present work, we analyze a technique designed by Geraci et al. in [1,11] named the Truncate and Encode (TE) strategy. It was presented as a non-intrusive method for steady and non-steady Partial Differential Equations (PDEs) in Uncertainty Quantification (UQ), and as a weakly intrusive method in the unsteady case. We analyze the TE algorithm applied to the approximation of functions, and in particular its performance for piecewise smooth functions. We carry out some numerical experiments, comparing the performance of the algorithm when using different linear and non-linear interpolation techniques and provide some recommendations that we find useful in order to achieve a hig…
On Daugavet indices of thickness
2020
Inspired by R. Whitley's thickness index the last named author recently introduced the Daugavet index of thickness of Banach spaces. We continue the investigation of the behavior of this index and also consider two new versions of the Daugavet index of thickness, which helps us solve an open problem which connect the Daugavet indices with the Daugavet equation. Moreover, we will improve the formerly known estimates of the behavior of Daugavet index on direct sums of Banach spaces by establishing sharp bounds. As a consequence of our results we prove that, for every $0<\delta<2$, there exists a Banach space where the infimum of the diameter of convex combinations of slices of the unit ball i…
Nambu structures and super-theorem of Amitsur-Levitzki
2004
In this thesis, we establish new polynomial identities in a non commutative combinatorial framework. In the first part, we present new Nambu-Lie structures by classifying all (n-1)-structures in \R^n and we give a method for defining all-order brackets in Lie algebras. We are able to quantify one of our structures, thanks to standard polynomials and even Clifford algebras. In the second part of our work, we generalize the notion of standard polynomials to graded algebras, and we prove an Amitsur-Levitzki type theorem for the Lie superalgebras \osp(1,2n) inspired by Kostant's cohomological interpretation of the classical theorem. We give super versions of properties and results needed in Kos…
Using Polynomial Loss and Uncertainty Information for Robust Left Atrial and Scar Quantification and Segmentation
2022
Automatic and accurate segmentation of the left atrial (LA) cavity and scar can be helpful for the diagnosis and prognosis of patients with atrial fibrillation. However, automating the segmentation can be difficult due to the poor image quality, variable LA shapes, and small discrete regions of LA scars. In this paper, we proposed a fully-automatic method to segment LA cavity and scar from Late Gadolinium Enhancement (LGE) MRIs. For the loss functions, we propose two different losses for each task. To enhance the segmentation of LA cavity from the multicenter dataset, we present a hybrid loss that leverages Dice loss with a polynomial version of cross-entropy loss (PolyCE). We also utilize …
Automated uncertainty quantification analysis using a system model and data
2015
International audience; Understanding the sources of, and quantifying the magnitude of, uncertainty can improve decision-making and, thereby, make manufacturing systems more efficient. Achieving this goal requires knowledge in two separate domains: data science and manufacturing. In this paper, we focus on quantifying uncertainty, usually called uncertainty quantification (UQ). More specifically, we propose a methodology to perform UQ automatically using Bayesian networks (BN) constructed from three types of sources: a descriptive system model, physics-based mathematical models, and data. The system model is a high-level model describing the system and its parameters; we develop this model …
Mapping field-scale spatial distribution patterns of size and activity of the denitrifier community
2008
International audience
Genetic determinisms, evolution and detection of non-target-site based resistance to herbicides inhibiting acetolactate-synthase in rye-grass (Lolium…
2016
The aim of this study is to unravel the genetic determinism of non-target-site resistance (NTSR) to herbicides inhibiting acetolactate-synthase (ALS) in the major weed rye-grass (Lolium sp.), and to estimate the feasibility of NTSR diagnosis based on genetic data. On the one hand, this work contributes to the understanding of the processes driving the evolution of NTSR to herbicides, and on the other hand it lays the foundations for the development of a diagnosis tool to identify NTSR to ALS inhibiting herbicides. - Using a quantitative transcriptome sequencing approach, we showed that NTSR evolve by recurrent selection of higher and higher constitutive expression levels of genes involved i…
Sédimentologie et quantification de la subsidence des séries liasiques dans le Haut Atlas Central marocain (coupe de Foum Zabel, région de Rich).
2007
13 pages; International audience
Exploring the diversity of listeria monocytogenes biofilm architecture by high-throughput confocal laser scanning microscopy and the predominance of …
2015
ABSTRACT Listeria monocytogenes is involved in food-borne illness with a high mortality rate. The persistence of the pathogen along the food chain can be associated with its ability to form biofilms on inert surfaces. While most of the phenotypes associated with biofilms are related to their spatial organization, most published data comparing biofilm formation by L. monocytogenes isolates are based on the quantitative crystal violet assay, which does not give access to structural information. Using a high-throughput confocal-imaging approach, the aim of this work was to decipher the structural diversity of biofilms formed by 96 L. monocytogenes strains isolated from various environments. Pr…