Lagrangian-Hamiltonian unified formalism for field theory

The RuskSkinner formalism was developed in order to give a geometrical unified formalism for describing mechanical systems. It incorporates all the characteristics of Lagrangian and Hamiltonian descriptions of these systems (including dynamical equations and solutions, constraints, Legendre map, evolution operators, equivalence, etc.). In this work we extend this unified framework to first-order classical field theories, and show how this description comprises the main features of the Lagrangian and Hamiltonian formalisms, both for the regular and singular cases. This formulation is a first step toward further applications in optimal control theory for partial differential equations. 2004 American Institute of Physics.

Las competencias genéricas en el Grado de Derecho y su evaluación

[spa] El presente estudio versa sobre la evaluación de competencias transversales en el Grado de Derecho a través del uso del portafolio digital. A tal fin son definidos los objetivos a alcanzar, las fases en su aplicación; la selección de las competencias a evaluar, así como una tabla de equivalencias entre actividades y competencias. Dicho portafolio electrónico nos ha permitido hacer el seguimiento, monitorización y evaluación de las competencias de los estudiantes. Se ha escogido deliberadamente llevar a cabo únicamente la evaluación de las competencias genéricas o transversales. La implantación del portafolio se ha hecho como experiencia piloto en un grupo de 90 estudiantes de doble titulación en la Facultad de Derecho de la Universidad de Barcelona.

3D solutions in transmission electron (Cryo) -microscopy in biology

One of the main problems in transmission electron microscopy in thebiological field is the tri-dimensionality. This article explains the technicalprocedures and requirements to prepare biological specimens preserving themclosest to their native state to perform 3D reconstruction of the macromolecularcomplexes and cellular structures in their natural environment.

The Biblioteca de Catalunya: working for the present and the future

The Biblioteca de Catalunya (BC) was created in 1907 by the Institut d’Estudis Catalans (IEC). In 1914 the Mancomunitat de Catalunya gave the library its condition of cultural and public service, open to researchers and scholars. The library underwent several changes as a consequence of political events, along the most of 20th century. In 1981 it was recognized by law as national library and it recovered its foundational aim of gathering, preserving and disseminating the bibliographical output of Catalonia and the production related with the Catalan linguistic field. As the proud host of ANADP2, the BC wants to show the attendees to the conference how, since 2004, has positioned itself to face the challenge of the new informational and technological paradigm. The library strategy for oncoming years includes giving open and free access online to the digitization of many of his collections through the portals MDC (Digital Memory of Catalonia), ARCA (Old Catalan Serials Archive) and Google Books project; the creation of the Web Archive of Catalonia and, as the last step in the consolidation of its policy, a high-security preserving repository named COFRE, based on the international guidelines and initiatives and the experience of the BC itself.

On the tractability of the piecewise-linear approximation for general discrete-choice network revenue management

The choice network revenue management (RM) model incorporates customer purchase behavioras customers purchasing products with certain probabilities that are a function of the offeredassortment of products, and is the appropriate model for airline and hotel network revenuemanagement, dynamic sales of bundles, and dynamic assortment optimization. The underlyingstochastic dynamic program is intractable and even its certainty-equivalence approximation, inthe form of a linear program called Choice Deterministic Linear Program (CDLP) is difficultto solve in most cases. The separation problem for CDLP is NP-complete for MNL with justtwo segments when their consideration sets overlap; the affine approximation of the dynamicprogram is NP-complete for even a single-segment MNL. This is in contrast to the independentclass(perfect-segmentation) case where even the piecewise-linear approximation has been shownto be tractable. In this paper we investigate the piecewise-linear approximation for network RMunder a general discrete-choice model of demand. We show that the gap between the CDLP andthe piecewise-linear bounds is within a factor of at most 2. We then show that the piecewiselinearapproximation is polynomially-time solvable for a fixed consideration set size, bringing itinto the realm of tractability for small consideration sets; small consideration sets are a reasonablemodeling tradeoff in many practical applications. Our solution relies on showing that forany discrete-choice model the separation problem for the linear program of the piecewise-linearapproximation can be solved exactly by a Lagrangian relaxation. We give modeling extensionsand show by numerical experiments the improvements from using piecewise-linear approximationfunctions.

Estudi i anàlisi dels hàbits esportius dels alumnes de l’IES Isaac Albèniz de Badalona

Aquest estudi té com objectiu conèixer els hàbits esportius dels alumnes del IES Isaac Albèniz de Badalona, no obstant els hàbits esportiu és un conjunt d’accions difícilment d’estudiar amb exactitud. Per tant l’estudi és centra principalment en conèixer el índex d’activitat física dels alumnes, el tipus d’activitat física que realitzen, els motius de pràctica i les barreres que dificulten la pràctica. La mostra analitzada és l’alumnat d’ESO que està format per 367 alumnes, 196 són nois i 171 són noies de 11 a 17 anys. El instrument de mesura utilitzat és una enquesta d’elaboració pròpia però amb referències del (MSD, 2011), aquesta enquesta s’ha administrat personalment als alumnes al principi de les classes d’educació física, posteriorment s’ha tractat les dades mitjançant el programa estadístic SPSS 20 per realitzar taules de contingència i gràfic de barres, finalment els resultats han mostrat una equivalència entre alumnes actius i no actius, que hi ha més percentatge de pràctica d’activitat física no organitzada que activitat física organitzada, que els principals motius de pràctica són la diversió i la salut, i que la falta de temps és la barrera que predomina més en els alumnes.

Fiesta peninsular y holiday estadounidense: dos visiones

Este artículo parte de la hipótesis de que la palabra fiesta posee un peso semántico mayor que su correspondiente holiday norteamericana y que esta desigualdad se puede corroborar en el ámbito de la antropología, la literatura, la lexicografía y la semántica lingüística. La falta de equivalencia semántica de ambos vocablos puede ocasionar dificultades en encuentros interculturales, ya que la traducción literal no consigue transmitir las diversas connotaciones semánticas de la fiesta. Convendría, pues, evitar tanto que el estudiante hispanohablante vuelque en el sustantivo estadounidense sus nociones culturales festivas, como que el estudiante norteamericano de español reduzca el término lingüístico al colorismo de una celebración lúdica o incluso taurina.

Parameterization of written signatures based on EFD

In this work we propose a method to quantify written signatures from digitalized images based on the use of Elliptical Fourier Descriptors (EFD). As usually signatures are not represented as a closed contour, and being that a necessary condition in order to apply EFD, we have developed a method that represents the signatures by means of a set of closed contours. One of the advantages of this method is that it can reconstruct the original shape from all the coefficients, or an approximated shape from a reduced set of them finding the appropriate number of EFD coefficients required for preserving the important information in each application. EFD provides accurate frequency information, thus the use of EFD opens many possibilities. The method can be extended to represent other kind of shapes.

Lipase Improvement: Goals and strategies

Lipases have received great attention as industrial biocatalysts in areas like oils and fats processing, detergents, baking, cheese making, surface cleaning, or fine chemistry . They can catalyse reactions of insoluble substrates at the lipid-water interface, preserving their catalytic activity in organic solvents. This makes of lipases powerful tools for catalysing not only hydrolysis, but also various reverse reactions such as esterification, transesterification, aminolysis, or thiotransesterifications in anhydrous organic solvents. Moreover, lipases catalyse reactions with high specificity, regio and enantioselectivity, becoming the most used enzymes in synthetic organic chemistry. Therefore, they display important advantages over classical catalysts, as they can catalyse reactions with reduced side products, lowered waste treatment costs, and under mild temperature and pressure conditions. Accordingly, the use of lipases holds a great promise for green and economical process chemistry.

Análisis de dos traducciones de la obra The Importance of Being Earnest, de Oscar Wilde

El siguiente trabajo consiste en el análisis de dos traducciones, una al catalán y otra al castellano, de la comedia The Importance of Being Earnest de Oscar Wilde. El análisis se centra en los aspectos más problemáticos de la traducción de esta obra

On the preservation of combinatorial types for maps on trees

We study the preservation of the periodic orbits of an A-monotone tree map f:T→T in the class of all tree maps g:S→S having a cycle with the same pattern as A. We prove that there is a period-preserving injective map from the set of (almost all) periodic orbits of ƒ into the set of periodic orbits of each map in the class. Moreover, the relative positions of the corresponding orbits in the trees T and S (which need not be homeomorphic) are essentially preserved

Hybrid model of a double-fed induction machine and back-to-back converter

This report details the port interconnection of two subsystems: a power electronics subsystem (a back-to-back AC/AC converter (B2B), coupled to a phase of the power grid), and an electromechanical subsystem (a doubly-fed induction machine (DFIM), coupled mechanically to a flywheel and electrically to the power grid and to a local varying load). Both subsystems have been essentially described in previous reports (deliverables D 0.5 and D 4.3.1), although some previously unpublished details are presented here. The B2B is a variable structure system (VSS), due to the presence of control-actuated switches: however from a modelling and simulation, as well as a control-design, point of view, it is sensible to consider modulated transformers (MTF in the bond-graph language) instead of the pairs of complementary switches. The port-Hamiltonian models of both subsystems are presents and coupled through a power-preserving interconnection, and the Hamiltonian description of the whole system is obtained; detailed bond-graphs of all the subsystems and the complete system are provided.

Energy-based modelling and simulation of the interconnection of a back-to-back converter and a doubly-fed induction machine

This paper describes the port interconnection of two subsystems: a power electronics subsystem (a back-to-back AC/CA converter (B2B), coupled to a phase of the power grid), and an electromechanical subsystem (a doubly-fed induction machine (DFIM). The B2B is a variable structure system (VSS), due to presence of control-actuated switches: however, from a modelling simulation, as well as a control-design, point of view, it is sensible to consider modulated transformers (MTF in the bond graph language) instead of the pairs of complementary switches. The port-Hamiltonian models of both subsystems are presented and, using a power-preserving interconnection, the Hamiltonian description of the whole system is obtained; detailed bond graphs of all subsystems and the complete system are also provided. Using passivity-based controllers computed in the Hamiltonian formalism for both subsystems, the whole model is simulated; simulations are run to rest the correctness and efficiency of the Hamiltonian network modelling approach used in this work.

Language variation in source texts and their translations: the case of L3 in film translation

In addition to the two languages essentially involved in translation, that of the source text (L1) and that of the target text (L2), we propose a third language (L3) to refer to any other language(s) found in the text. L3 may appear in the source text (ST) or the target text (TT), actually appearing more frequently inSTs in our case studies. We present a range of combinations for the convergence and divergence of L1, L2 and L3, for the case of feature films and their translations using examples from dubbed and subtitled versions of films, but we are hopeful that our tentative conclusions may be relevant to other modalities of translation, audiovisual and otherwise. When L3 appears in an audiovisual ST,we find a variety of solutions whereby L3 is deleted from or adapted to the TT.In the latter case, L3 might be rendered in a number of ways, depending on factors such as the audience’s familiarity with L3, and the possibility that L3 inthe ST is an invented language.

Análisis contrastivo de la subtitulación vista desde dos prismas: el descriptivismo y el prescriptivismo

The purpose of the present article is to describe subtitling from two opposite translation approaches. This contrast attempts to highlight the importance of erasing prescriptive ideas not only in order to use strategies based on dynamic equivalence, but also to fully accept and understand translation in general, and subtitling, as a restricted form of translation, in particular. The article is divided into four sections: (a) prescriptivism and its theoretical framework, with its most relevant aspects examined in relation tosubtitling; (b) descriptivism and its theoretical framework, considered in relation tosubtitling; (c) a contrastive chart that summarises the basic features of both approachesand allows the reader to compare them at a glance; (d) findings, in which conclusions are drawn and a personal view is stated.