First-principles study of the neutral molecular metal Ni(tmdt)2.

The electronic structure of the molecular solid Ni(tmdt)2, the only well characterized neutral molecular metal to date, has been studied by means of first-principles density functional calculations. It is shown that these calculations correctly describe the metallic vs semiconducting behavior of molecular conductors of this type. The origin of the band overlap leading to the metallic character and the associated Fermi surfaces has been studied.

The automorphism group of a free-by-cyclic group in rank 2

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Contractions in the 2-wasserstein lenght space and thermalization of granular media

An algebraic decay rate is derived which bounds the time required for velocities to equilibrate in a spatially homogeneous flow-through model representing the continuum limit of a gas of particles interacting through slightly inelastic collisions. This rate is obtained by reformulating the dynamical problem as the gradient flow of a convex energy on an infinite-dimensional manifold. An abstract theory is developed for gradient flows in length spaces, which shows how degenerate convexity (or even non-convexity) | if uniformly controlled | will quantify contractivity (limit expansivity) of the flow.

Periodic orbits near a heteroclinic loop formed by one dimensional orbit and a 2-dimensional manifold: application to the charged collinear 3-body problem

The paper is devoted to the study of a type of differential systems which appear usually in the study of some Hamiltonian systems with 2 degrees of freedom. We prove the existence of infinitely many periodic orbits on each negative energy level. All these periodic orbits pass near the total collision. Finally we apply these results to study the existence of periodic orbits in the charged collinear 3���body problem.

Human capital in a global and knowledge-based economy. Part 2. Asssessment at the EU country level.

This report is an extension and partial update of de la Fuente and Ciccone (2002). It constructs estimates of the private and social rates of return on schooling for fourteen EU countries using microeconometric estimates of Mincerian wage equations, the results of cross-country growth regressions and OECD data on educational expenditures, tax rates and social benefits. The results are used to draw some tentative conclusions regarding the optimality of observed investment patterns and educational subsidy levels.

Refilling meridians in a genus 2 handlebody complement

Suppose a genus two handlebody is removed from a 3-manifold M and then a single meridian of the handlebody is restored. The result is a knot or link complement in M and it is natural to ask whether geometric properties of the link complement say something about the meridian that was restored. Here we consider what the relation must be between two not necessarily disjoint meridians so that restoring each of them gives a trivial knot or a split link.

Non compact euclidean cone 3-manifolds with cone angles less than 2���

We study of noncompact Euclidean cone manifolds with cone angles less than c&2�� and singular locus a submanifold. More precisely, we describe its structure outside a compact set. As a corol lary we classify those with cone angles & 2��/3 and those with cone angles = 2��/3.

CM points and weight 3=2 modular forms

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Dise��o y fabricaci��n de una antena con diversidad en polarizaci��n para redes WIFI a 2,4 GHz

Existeixen diferents tecnologies de transmissi�� sense fils, per�� la m��s coneguda ��s la tecnologia WIFI (Wireless Fidelity) que opera a la banda dels 2,4 GHz a Europa. Aquest tipus de xarxes opera en entorns indoor, on el canal est�� sotm��s a una aleatorietat i complexitat elevades degut a la pres��ncia d���una gran quantitat d���elements que poden fer que la senyal rebuda presenti variacions importants en les seves caracter��stiques (nivell de senyal, polaritzaci��...). Aquest fet motiva la necessitat de desenvolupar i implantar sistemes de comunicacions amb solucions per poder minimitzar els efectes provocats per l���entorn a la senyal. Per poder pal��liar aquestes variacions, en aquest projecte s���ha dissenyat i fabricat una antena formada per dos dipols disposats un ortogonal a l���altre de manera que existeixi diversitat en polaritzaci��. La freq����ncia de treball de la antena ��s de 2,4 GHz. Rebuda una senyal de RF, el circuit de commutaci�� permetr�� seleccionar el dipol pel qual es rep la senyal de RF amb una major pot��ncia.

Full T��cnic. Conreus Extensius. Comarques de Girona, n��m. 2 (2006)

- Resultats de les noves varietats d���ordi. - Recomanaci�� de varietats d���ordi. - Caracter��stiques agron��miques de les varietats recomanades.

BOI 2.0: disseny d'una implementaci�� de JPEG 2000

JPEG 2000 ��s un est��ndard de compressi�� d'imatges que utilitza t��cniques estat de l���art basades en la transformada wavelet. Els principals avantatges s��n la millor compressi��, la possibilitat d���operar amb dades comprimides i que es pot comprimir amb i sense p��rdua amb el mateix m��tode. BOI ��s la implementaci�� de JPEG 2000 del Grup de Compressi�� Interactiva d���Imatges del departament d���Enginyeria de la Informaci�� i les Comunicacions, pensada per entendre, criticar i millorar les tecnologies de JPEG 2000. La nova versi�� intenta arribar a tots els extrems de l���est��ndard on la versi�� anterior no va arribar.

QoS support in satellite and wireless networks: study under the network simulator (NS-2)

Aquest projecte es basa en l'estudi de l'oferiment de qualitat de servei en xarxes wireless i satel��litals. Per aix�� l'estudi de les t��cniques de cross-layer i del IEEE 802.11e ha sigut el punt clau per al desenvolupament te��ric d���aquest estudi. Usant el simulador de xarxes network simulator, a la part de simulacions es plantegen tres situacions: l'estudi de la xarxa satel��lital, l'estudi del m��tode d'acc��s HCCA i la interconnexi�� de la xarxa satel��lital amb la wireless. Encara que aquest ��ltim punt, incomplet en aquest projecte, ha de ser la continuaci�� per a futures investigacions.

Homotopy limits for 2-categories

We study homotopy limits for 2-categories using the theory of Quillen model categories. In order to do so, we establish the existence of projective and injective model structures on diagram 2-categories. Using these results, we describe the homotopical behaviour not only of conical limits but also of weighted limits. Finally, pseudo-limits are related to homotopy limits.

A classification, up to hyperbolicity, of groups given by 2 generators and one relator of length 8

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Traficando identidades: la construcci��n del ethos intermedio en Cr��nica da Rua 513.2 de Jo��o Paulo Borges Coelho

En Cr��nica da Rua 513.2 (2006), Borges Coelho construye un nuevo lugar de escritura en la literatura mozambique��a. Se trata del espacio del ethos intermedio, constituyendo la indicianidad el culminar de esta configuraci��n. En este estudio es analizado, a partir de una metodolog��a interdisciplinar, el conjunto de estrategias utilizadas por el narrador que cristaliza la constituci��n de este ethos: la onom��stica y el espacio-temporalidad. Estos aspectos ser��n estudiados en el conjunto de la novela y en el caso espec��fico del personaje de origen indio, Valgy, a��adi��ndose el estudio de la voz y los grados de alteridad que emergen del texto