Nonsingular Decaying Vacuum Cosmology and Entropy Production within the Generalized Second Law of Thermodynamics

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2020, Tutor:Joan Solà PeracaulaWithin the framework of the running vacuum cosmology models, we solve Friedmann's equations and calculate the entropy of the apparent horizon, checking that the Generalized Second Law of thermodynamics is satis ed which implies to compute the contribution from both the usual entropy inside it as well as the contribution from its surface. We also show that the model solves the horizon problem and obtain constraints on the model's parameters through our thermodynamical analysis

Analysis of a moving mask approximation for martensitic transformations

In this work we introduce a moving mask approximation to describe the dynamics of austenite to martensite phase transitions at a continuum level. In this framework, we prove a new type of Hadamard jump condition, from which we deduce that the deformation gradient must be of the form $\mathsf{1} +\mathbf{a}\otimes \mathbf{n}$ a.e. in the martensite phase. This is useful to better understand the complex microstructures and the formation of curved interfaces between phases in new ultra-low hysteresis alloys such as Zn45Au30Cu25, and provides a selection mechanism for physically-relevant energy-minimising microstructures. In particular, we use the new type of Hadamard jump condition to deduce a rigidity theorem for the two well problem. The latter provides more insight on the cofactor conditions, particular conditions of supercompatibility between phases believed to influence reversibility of martensitic transformations

Centrality and connectivity in public transport networks and their significance for transport sustainability in cities

The promotion of public transport as a backbone of mobility in urban agglomerations, or at least as an alternative to the dominance of the automobile, has become a prominent policy focus in most large cities around the world. However, while some cities have been successful in shifting car journeys onto rail and buses, others are struggling despite considerable effort to make public transport more attractive. This paper provides a brief overview of success factors for public transport and then takes the configuration of public transport networks as a vantage point for policy evaluation. The development of centrality and connectivity indicators for the public transport network of Melbourne's north-eastern suburbs delivers an instrument for assessing the congruence of the systems with the geographical structure of central areas and urban activities in these cities. It is hypothesised that a higher number of convenient transfer points and a choice of routes to users (network connectivity), as well as a high degree of spatial overlap and integration between public transport infrastructure and urban activity centres and corridors (centrality of facilities) will lead to a greater role for public transport in the mobility patterns of the city as a whole

First record of powdery scab caused by Spongospora subterranea subsp. subterranea on potato in Malta

Disease note describing the first recording of powdery scab on potatoes in Malta.peer-reviewe

First record of Verticillium dahliae on olive in Malta

Disease note describing the first record of Verticillium dahliae on olive in Maltapeer-reviewe

Operator inequalities related to the Corach--Porta--Recht inequality

We prove some refinements of an inequality due to X. Zhan in an arbitrary complex Hilbert space by using some results on the Heinz inequality. We present several related inequalities as well as new variants of the Corach--Porta--Recht inequality. We also characterize the class of operators satisfying $\left\Vert SXS^{-1}+S^{-1}XS+kX\right\Vert \geq (k+2)\left\Vert X\right\Vert$ under certain conditions.Comment: 12 Pages, to appear in Linear Algebra Appl. (LAA