Phase-coexisting patterns, horizontal segregation and controlled convection in vertically vibrated binary granular mixtures

We report new patterns, consisting of coexistence of sub-harmonic/harmonic and asynchronous states [for example, a granular gas co-existing with (i) bouncing bed, (ii) undulatory subharmonic waves and (iii) Leidenfrost-like state], in experiments on vertically vibrated binary granular mixtures in a Heleshaw-type cell. Most experiments have been carried out with equimolar binary mixtures of glass and steel balls of same diameter by varying the total layer-height ($F$) for a range of shaking acceleration ($\Gamma$). All patterns as well as the related phase-diagram in the ($\Gamma, F$)-plane have been reproduced via molecular dynamics simulations of the same system. The segregation of heavier and lighter particles along the horizontal direction is shown to be the progenitor of such phase-coexisting patterns as confirmed in both experiment and simulation. At strong shaking we uncover a {\it partial} convection state in which a pair of convection rolls is found to coexist with a Leidenfrost-like state. The crucial role of the relative number density of two species on controlling the buoyancy-driven granular convection is demonstrated. A possible model for spontaneous horizontal segregation is suggested based on anisotropic diffusion

Rigidity for C1C^1 actions on the interval arising from hyperbolicity I: solvable groups

We consider Abelian-by-cyclic groups for which the cyclic factor acts by hyperbolic automorphisms on the Abelian subgroup. We show that if such a group acts faithfully by $C^1$ diffeomorphisms of the closed interval with no global fixed point at the interior, then the action is topologically conjugated to that of an affine group. Moreover, in case of non-Abelian image, we show a rigidity result concerning the multipliers of the homotheties, despite the fact that the conjugacy is not necessarily smooth. Some consequences for non-solvable groups are proposed. In particular, we give new proofs/examples yielding the existence of finitely-generated, locally-indicable groups with no faithful action by $C^1$ diffeomorphisms of the interval.Comment: A more detailed proof of Proposition 4.15 adde

Mobilizing resources for war: the British and Spanish intelligence systems during the war of Jenkins' Ear (1739-1744)

The topic of this study is the War of Jenkins’ Ear (1739 – 1744) and this thesis concentrates on the close connection between the British and Spanish gathering of intelligence and the military decisions adopted in London and Madrid during the war. The ultimate purpose of this study is to put this war in a broader context and make a contribution to understand the development of the state in eighteenth century Europe. The first part of this study analyses the structure and functioning of the several British and Spanish Intelligence Networks, i.e. diplomatic and political support to these networks, expenditures, flowing of intelligence, messengers, agents, collaborators and counter intelligence. This part consists of two chapters, as follows: (a) the British Intelligence System and (b) the Spanish Intelligence System. The second part of the study explores the connection between the gathering of intelligence and decision-making in Madrid and London. However, the study of the use of intelligence can be problematic. This is because neither on the British nor the Spanish side are there official cabinet records for this period that could directly link one process with the other. In an attempt to solve this difficulty it has been decided to study the connection through four case studies. Each of them will concentrate on one of the military expeditions that Britain and Spain carried out or planned during the war

Estudio fisiográfico-sedimentológico de las rías altas del Norte de Lugo

Esta breve comunicación forma parte de una investigación, cuyo conjunto es tema de la tesis doctoral de uno de nosotros (N. T. R.). Se estudian ciertos fenómenos de erosión y sedimentación que tienen lugar en estas rías del litoral cantábrico, a partir de las características morfológicas y de textura que ofrecen los materiales detríticos litorales y continentales en sus márgenes.Estos accidentes geográficos vienen sufriendo un acentuado fenómeno de relleno por materiales procedentes del mar de tipo arenoso y de tierra, de carácter térreo-fangoso ; tal proceso de relleno se ha acentuado a medida que se han desarrollado las marismas, junqueras y bajos de arena, de tal modo, que actualmente el acceso a las zonas interiores portuarias se hace con dificultad. La deposición de sedimentos es debida al desequilibrio existente entre los aportes de materiales procedentes del mar y de tierra y el poder de arrastre del juego de mareas y corrientes en el ámbito de las rías. En consecuencia, el tema es de gran interés no sólo desde el punto de vista de la investigación científica, sino también utilitario de tipo  técnico, puesto que plantea problemas relacionados con el acceso a zonas portuarias a lo largo de vías de comunicación marítima