1,721,147 research outputs found
Comparing double porosity and single porosity models for the simulation of coupled chemo-hydro-mechanical behavior of compacted active clays
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Innovazione organizzativa nel trasporto aereo: un'analisi delle strategie dei vettori low cost
No full textModeling the coupled chemo-hydro-mechanical behavior of compacted active clays
No full textEngineering clay barriers are one of the main solutions considered for the containment of waste,
both within the context of landfills and, in perspective of longer operational times, of nuclear waste disposal.
Modeling the performance of these barriers in the long term can be difficult, since the behavior of active clays
highly depends on variables such as temperature, degree of saturation and suction, and chemistry of the wetting
fluid.This paper deals with the effects of chemical changes. Based on microstructural evidence, a double structure
model for coupled chemo-hydro mechanical processes is formulated. The model is then used to reproduce a salt
transport test run in oedometer conditions. Some implications of the proposed double porosity approach are
highlighted and discussed. The frame has the advantage of being based on direct microstructural evidence and
of allowing for joint interpretation of hydro and mechanical changes. The frame also shares characteristics
with models used to reproduce the behavior of clays in unsaturated conditions, so making it appealing for its
implementation within a wider context
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Double-structure effects on the chemo-hydro-mechanical behaviour of a compacted active clay
No full textThis work presents an insight into double-structure effects on the coupled chemo-hydro-mechanical behaviour of a compacted active clay. In the first part, selected pore size distribution curves are introduced, to highlight the influence of solute concentration on the evolution of the microstructure of compacted samples. An aggregated structure with dual-pore network is induced by compaction even at relatively high water contents. This structural arrangement is enhanced by salinisation, and has a notable influence on transient volume change behaviour – that is, the occurrence of different stages of swelling upon pore water dilution and higher volume change rates upon salinisation. A coupled chemo-hydro-mechanical model, taking into consideration double-structural features from a chemo-mechanical viewpoint, is described and then used to interpret these behavioural responses and present complementary information on local transient processes. The model is designed to identify an intra-aggregate and an inter-aggregate domain, and assigns different values of hydraulic pressure and osmotic suction to each domain. Distinct constitutive laws for both domains are formulated, and the flow of salt and water between the two domains is accounted for by a physically based mass exchange term. The model is used to simulate salt diffusion tests run in an oedometer at constant vertical stress. Parameters used in the formulation are calibrated based on separate experimental evidence, both through direct test results and through back-analyses of laboratory experiments
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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