Search results for " statistics"
showing 10 items of 1891 documents
The Duality of Entropy/Extropy, and Completion of the Kullback Information Complex
2018
The refinement axiom for entropy has been provocative in providing foundations of information theory, recognised as thoughtworthy in the writings of both Shannon and Jaynes. A resolution to their concerns has been provided recently by the discovery that the entropy measure of a probability distribution has a dual measure, a complementary companion designated as &ldquo
A New Image Distortion Measure Based on Natural Scene Statistics Modeling
2012
In the field of Image Quality Assessment (IQA), this paper examines a Reduced Reference (RRIQA) measure based on the bi-dimensional empirical mode decomposition. The proposed measure belongs to Natural Scene Statistics (NSS) modeling approaches. First, the reference image is decomposed into Intrinsic Mode Functions (IMF); the authors then use the Generalized Gaussian Density (GGD) to model IMF coefficients distribution. At the receiver side, the same number of IMF is computed on the distorted image, and then the quality assessment is done by fitting error between the IMF coefficients histogram of the distorted image and the GGD estimate of IMF coefficients of the reference image, using the …
Conflict in Somalia: impact on child undernutrition
2017
Background: In Somalia, protracted conflict and persistent drought have caused population displacement and livelihood destruction. As a result, there is widespread child malnutrition. We aimed to determine the effects of conflict on wasting and stunting among children aged 6-59 months in Somalia 2007–2010.\ud \ud Methods: Data were from household nutritional surveys from 2007 to 2010, with 1,066 clusters covering 73,778 children, the Armed Conflict Location and Event Data (ACLED) project and remote sensing. We used Bayesian hierarchical spatial-temporal regression methods to examine the effects of conflict on wasting and stunting. A preliminary model included individual, household and envir…
Large eddy simulation of inertial particles dispersion in a turbulent gas-particle channel flow bounded by rough walls
2020
The purpose of this paper is to understand the capability and consistency of large eddy simulation (LES) in Eulerian–Lagrangian studies aimed at predicting inertial particle dispersion in turbulent wall-bounded flows, in the absence of ad hoc closure models in the Lagrangian equations of particle motion. The degree of improvement granted by LES models is object of debate, in terms of both accurate prediction of particle accumulation and local particle segregation; therefore, we assessed the accuracy in the prediction of the particle velocity statistics by comparison against direct numerical simulation (DNS) of a finer computational mesh, under both one-way and two-way coupling regimes. We p…
Weak convergence to the coalescent in neutral population models
1999
For a large class of neutral population models the asymptotics of the ancestral structure of a sample of n individuals (or genes) is studied, if the total population size becomes large. Under certain conditions and under a well-known time-scaling, which can be expressed in terms of the coalescence probabilities, weak convergence in D E ([0,∞)) to the coalescent holds. Further the convergence behaviour of the jump chain of the ancestral process is studied. The results are used to approximate probabilities which are of certain interest in applications, for example hitting probabilities.
A Geometric Approach to Automatic Description of Iconic Scenes
2005
It is proposed a step towards the automatic description of scenes with a geometric approach. The scenes considered are composed by a set of elements that can be geometric forms or iconic representation of objects. Every icon is characterized by a set of attributes like shape, colour, position, orientation. Each scene is related to a set of sentences describing its content. The proposed approach builds a data driven vector semantic space where the scenes and the sentences are mapped. Sentences and scene with the same meaning are mapped in near vectors and distance criteria allow retrieving semantic relations.
Concienciación juvenil frente al COVID-19 en España y Latinoamérica: análisis de spots en YouTube
2021
Introducción. Las consecuencias socio-sanitarias y económicas del COVID-19 llevó a los países a adoptar estrategias comunicativas de carácter preventivo, que difundieron en medios sociales para amplificar su difusión. Esta investigación analiza spots del contexto español y latinoamericano (N=100) orientados a concienciar a los jóvenes frente al COVID-19 publicados durante el periodo de 1 septiembre 2020 a 10 enero 2021 y accesibles en YouTube. Metodología. La metodología es mixta: cualitativa, se analizan variables comunicativas, técnico-narrativas y afectivo-emocionales; y cuantitativa, con análisis descriptivo de los datos y posterior análisis de varianza para identificar las diferencias …
Minimum Leading Edge Protection Application Length to Combat Rain-Induced Erosion of Wind Turbine Blades
2021
Leading edge erosion (LEE) repairs of wind turbine blades (WTBs) involve infield application of leading edge protection (LEP) solutions. The industry is currently aiming to use factory based LEP coatings that can applied to the WTBs before they are shipped out for installation. However, one of the main challenges related to these solutions is the choice of a minimum LEP application length to be applied in the spanwise direction of the WTBs. Generally, coating suppliers apply 10–20 m of LEP onto the blades starting from the tip of the blade using the “rule of thumb”, and no studies in the literature exist that stipulate how these LEP lengths can be calculated. In this study, we extend the sc…
Expertise et suivi d'une acquisition Lidar pour l'archéologie : l'exemple d'Autun
2014
National audience; Présentation de l'expertise mise en œuvre pour vérifier et valider une campagne d'acquisition de données LiDAR pour des objectifs archéologiques
Quelles synergies entre gestionnaires d'espaces protégés et scientifiques pour l'acquisition et la valorisation de données terrestres haute-résolutio…
2015
National audience; Le LIDAR est une technique de télédétection aéroportée permettant d'acquérir des images à haute résolution avec de multiples finalités, comme l'analyse des paysages anciens et l'évolution des paysages actuels. Très sensible et relativement coûteux, son usage requiert une importante technicité et expertise à toutes les étapes, de l'acquisition à la valorisation des données en passant par leur traitement. Cet exposé présente le partenariat impliquant gestionnaires, ingénieurs, et chercheurs mis en place entre le futur Parc national et la Maison des sciences de l'Homme de l'Université de Bourgogne, pour la réussite de l'opération.