Search results for "Modell"

Fra ricerca empirica e storiografia. Modelli di spazio in linguistica

2006

L’articolo ricostruisce alcuni momenti chiave del rapporto fra scienze del linguaggio e la nozione di spazio. Utilizzando una bibliografia assai ampia di taglio pluridisciplinare (linguistico, filosofico, sociologico, psicologico, geografico), si mettono in luce le difficoltà e i fallimenti di ampi settori della linguistica del ‘900 nel confrontarsi con la nozione di spazio sia da un punto di vista teorico che empirico. Particolare attenzione viene posta alla fase della nascita della geolinguistica da un lato e della sociolinguistica dall’altro. Nella seconda parte dell’articolo vengono presi in esame alcuni modelli recenti emersi all’interno della dialettologa percettiva e della sociolingu…

Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses

2011

The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for (137)Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil a…

Quantifying interrill and ephemeral gully erosion in a small Sicilian basin

2012

Advances in Laboratory Testing and Modelling of Soils and Shales (ATMSS).

2017

This volume contains the invited keynote and feature lectures, as well as the papers that have been presented at the workshop. The topics of the lectures and papers cover a wide range of theoretical and experimental research, including unsaturated behaviour of soils and shales, multiphysical testing of geomaterials, hydromechanical behaviour of shales and stiff clays, the geomechanical behaviour of the Opalinus Clay shale, advanced laboratory testing for site characterization and in situ applications, and soil–structure interactions.

4D paleoenvironmental evolution of the Early Triassic Sonoma Foreland Basin (western USA)

2017

In the wake of the Mesozoic, the Early Triassic (~251.95 Ma) corresponds to the aftermath of the most severe mass extinction of the Phanerozoic: the end-Permian crisis, when life was nearly obliterated (e.g., 90% of marine species disappeared). Consequences of this mass extinction are thought to have prevailed for several millions of years, implying a delayed recovery lasting the whole Early Triassic, if not more. Several paradigms have been established and associated to a delayed biotic recovery scenario expected to have resulted from harsh and deleterious paleoenvironments. These paradigms include a global anoxia in the marine realm, a “Lilliput” effect, and the presence of “disaster” tax…

Modelling of Pulsed Electro Acoustic Method for Space Charge Detection on Single and Multilayer Dielectrics

Topology of correlation-based minimal spanning trees in real and model markets

2003

We present here a topological characterization of the minimal spanning tree that can be obtained by considering the price return correlations of stocks traded in a financial market. We compare the minimal spanning tree obtained from a large group of stocks traded at the New York Stock Exchange during a 12-year trading period with the one obtained from surrogated data simulated by using simple market models. We find that the empirical tree has features of a complex network that cannot be reproduced, even as a first approximation, by a random market model and by the one-factor model.

Probabilité d'apparition d'un phénomène parasitaire et choix de modèles de régression logistique

2007

Epidemiological processes are now using spatial statistics and modelling tools. The main objective of most health risks studies consists in identifying potential contamination sources and factors capable of explaining their localization. Health data often prove binary (typically presence/absence) and specific methods such as binary logistic regression have to be used. This method's output consists in a probability for the pathogen of interest. A posterior classification of each sample is then conducted using a probability threshold. The method used to maximize this threshold is called the ROC curve which consists in giving a representation of the behaviour of the model and then to choose th…

Residential satisfaction and spatial configurations in a periurban area

2011

Since the 1960s, French cities are concerned with an urban sprawl process. This urban sprawl leads to the emergence of a particular space located at the interface between the city and the countryside: the periurban. The social, morphological or the spatial practices of its inhabitants give the suburban a particular singularity and specificity. It is a space of contradiction that attracts both because of the "natural" living environment that it provides to households, but also because of its proximity to the city and the opportunities related to accessibility to various urban amenities.To understand more precisely this enthusiasm for periurban areas, this thesis proposes to explore the indiv…

Linear stability analysis of gas-fluidized beds for the prediction of incipient bubbling conditions

2010

Abstract This work focuses on the development of a novel linear stability criterion for the state of homogeneous fluidization regime, based on a new mathematical model for gas-fluidized beds. The model is developed starting from the well-known particle bed model. A mono-dimensional momentum balance is derived leading to a set of equations which explicitly include voidage-gradient dependent terms (elastic force) for both solid and fluid phases. A fully predictive criterion for the stability of homogeneous fluidization state is here proposed, based on the well-known Wallis’ linear stability analysis. The criterion requires the choice of an appropriate averaging distance, which in the present …