Search results for "brique"
showing 10 items of 28 documents
Avaluació per rúbriques de la composició escrita, en educació primària
2016
L'objectiu d'aquest estudi és elaborar i validar un sistema de rúbriques com a instrument d'avaluació i informació dels processos docents, permetent el mesurament d'aprenentatges complexos, en concret, l'habilitat per compondre textos escrits, quan encara no està consolidada aquesta subcompetència; és a dir, durant el seu procés d'adquisició. El nivell educatiu seleccionat per a l'obtenció de les mostres de producció escrita és 2n Cicle d'Educació Primària, amb alumnes entre els 8 i 10 anys. I la qüestió és: avalua la rúbrica construïda el que intenta mesurar? Per a això, s'estudia l'acord interjutges, a través de la consistència interna de les variables -estadístic alfa de Cronbach- i mitj…
Geometry of the projectivization of ideals and applications to problems of birationality
2018
In this thesis, we interpret geometrically the torsion of the symmetric algebra of the ideal sheaf I_Z of a scheme Z defined by n+1 equations in an n-dimensional variety. This is equivalent to study the geometry of the projectivization of I_Z. The applications of this point of view concern, in particular, the topic of birational maps of the projective space of dimension 3 for which we construct explicit birational maps that have the same algebraic degree as their inverse, free and nearly-free curves for which we generalise a characterization of free curves by extending the notion of Milnor and Tjurina numbers. We tackle also the topic of homaloidal hypersurfaces, our original motivation, fo…
Uses of weeds as an economical alternative to processed wood biomass and fossil fuels
2016
Abstract The use of fossil fuels as a main source of energy is directly linked to global climate change (due to CO2 emission), so there is a necessity to find new, cheap and easily available energy sources for the earth’s inhabitants. Nowadays renewable energy sources are forced also for the mitigation of the effects of climate change as a result of greenhouse gases emission control. Decentralized sources of low-cost renewable fuels that may be used, in particular, in those households where there is no possibility of using gas or heat delivered from other sources should be of special interest. This paper describes the possibility of using untreated plants such as Canadian goldenrod (Solidag…
Effect of operating conditions and feedstock composition on the properties of manganese oxide or quartz charcoal pellets for the use in ferroalloy in…
2020
peer-reviewed The full text of this article will not be available until the embargo expires on the 26/12/2021 This study investigates the effect of heat treatment temperature on the properties of charcoal composite pellets used for the reduction of ferroalloys. The heavy fraction of biooil was used as a binder for the charcoal ore pellet preparation. The effect of heat treatment temperature on the pellet shrinkage was related to the degree of reduction which varied with feedstock and ore composition. The results showed that the size and shape of the charcoal pellets were not affected by the biooil devolatilization. Manganese charcoal pellets showed higher electrical resistance during pyroly…
Reed canary grass transportation costs – Reducing costs and increasing feasible transportation distances
2009
Abstract Reed canary grass is used in several heat and power plants in Finland and it is estimated that about 70–80 plants could utilise reed canary grass as a co-firing fuel. Long-distance transport of reed canary grass forms a significant share of the production and delivery costs. Reed canary grass can be transported in bales or as loose matter. The density of the matter and shape of the bales influence the load-size and the cost. At present it is impossible to obtain the full load-bearing capacity of a lorry even with bales, and with light bulk matter the obtainable load is less than one-third of the load-bearing capacity of a lorry. By using Orkel local-baler it has been possible to ob…
Actions de tores algébriques sur des corps de caractéristique zéro
2023
Over an algebraically closed field of characteristic zero, normal affine varieties endowed with an effective torus action were described by Altmann and Hausen in 2006 by a geometrico-combinatorial presentation.Using Galois descent tools, we extend this presentation to the case where the ground field is an arbitrary field of characteristic zero. In this context, the acting torus may be non split and may have non-trivial torsors, thus we need additional data to encode such varieties. We provide some situations where the generalized Altmann-Hausen presentation simplifies. For instance, if the acting torus is split, we recover mutatis mutandis the original Altmann-Hausen presentation. Finally, …
Dépôts carbonatés microbiens en domaine lacustre et fluviatile : fabriques et facteurs de contrôle
2020
The non-marine carbonates related to microbial activity display a large range of morphologies and compositions and accumulate in various settings (freshwater, alkaline, and saline lakes, fluvial environments, thermal and freshwater springs, …). The variety of non-marine microbial carbonates and their particularity led to propose numerous and complex terminologies and classifications, making their use complicated and restrictive for the interpretation of depositional settings. Mineralization of these carbonates results from the interaction between biotic factors (intrinsic) and environmental factors (extrinsic and external) at multi-scales. The first aim of this work was to characterize morp…
L'identité de Fay en théorie des systèmes intégrables
2011
Fay's identity on Riemann surfaces is a powerful tool in the context of algebro-geometric solutions to integrable equations. This relation generalizes a well-known identity for the cross-ratio function in the complex plane. It allows to establish relations between theta functions and their derivatives. This offers a complementary approach to algebro-geometric solutions of integrable equations with certain advantages with respect to the use of Baker-Akhiezer functions. It has been successfully applied by Mumford et al. to the Korteweg-de Vries, Kadomtsev-Petviashvili and sine-Gordon equations. Following this approach, we construct algebro-geometric solutions to the Camassa-Holm and Dym type …
Real Algebraic Geometry
2011
144 Pages; Cet ouvrage constitue les actes de la conférence de Géométrie Algébrique Réelle qui a eu lieu à Rennes du 20 au 24 Juin 2011