High-Speed Rail: lessons for policy makers from experiences abroad

In April 2009, the US government unveiled its blueprint for a national network of high-speed passenger rail (HSR) lines aimed at reducing traffic congestion, cutting national dependence on foreign oil and improving rural and urban environments. In implementing such a program, it is essential to identify the factors that might influence decision making and the eventual success of the HSR project, as well as foreseeing the obstacles that will have to be overcome.

Anàlisi de la gestió de fons d’inversió de renda variable en el període 2009-2013

La crisi financera que es va originar l’any 2007 va tenir uns efectes devastadors a tots els àmbits de l’economia. El mercat hipotecari es va desplomar i l’accés al crèdit es va restringir a la majoria de la població. Els efectes que va tenir la crisi sobre aquests mercats han estat analitzats i estudiats repetidament en diverses assignatures. Però el que es vol observar amb la realització d’aquest treball són els efectes que va provocar la crisi econòmica sobre un altre àmbit del mercat financer, el mercat de fons d’estalvi i més concretament, en el de fons d’inversió. Aquest treball vol analitzar si els mercats espanyol i europeu de fons d’inversió ha patit els efectes de la crisi econòmica i si ha estat així, en quin grau s’han vist afectats. Aquests mercats venen regits per experts professionals en la matèria i la rendibilitat d’aquests actius vindrà determinada per la gestió que aquests facin. Per poder mesurar si la seva gestió aconsegueix millorar els resultats que podríem obtenir invertint en el mercat, utilitzarem uns índexs financers anomenats mesures de performance. Dins el ventall disponible de fons d’inversió, ens centrarem en el mercat de renda variable ja que és el que presenta major variabilitat i està més sotmès a possibles canvis en el mercat. En concret s’analitzaran els resultats de la gestió del mercat de fons d’inversió de renda variable durant els anys posteriors a la crisi fins a l’actualitat tant al mercat espanyol com al mercat europeu per diferents categories de fons.

Front Speed of Language Replacement

We use two coupled equations to analyze the space-time dynamics of two interacting languages. Firstly, we introduce a cohabitation model, which is more appropriate for human populations than classical (non-cohabitation) models. Secondly, using numerical simulations we nd the front speed of a new language spreading into a region where another language was previously used. Thirdly, for a special case we derive an analytical formula that makes it possible to check the validity of our numerical simulations. Finally, as an example, we nd that the observed front speed for the spread of the English language into Wales in the period 1961-1981 is consistent with the model predictions. We also nd that the e¤ects of linguistic parameters are much more important than those of parameters related to population dispersal and reproduction. If the initial population densities of both languages are similar, they have no e¤ect on the front speed. We outline the potential of the new model to analyze relationships between language replacement and genetic replacement

Effect of tow-drop gaps on the damage resistance and tolerance of Variable-Stiffness Panels

This paper presents an experimental study of the effects of tow-drop gaps in Variable Stiffness Panels under drop-weight impact events. Two different configurations, with and without ply-staggering, have been manufactured by Automated Fibre Placement and compared with their baseline counterpart without defects. For the study of damage resistance, three levels of low velocity impact energy are generated with a drop-weight tower. The damage area is analysed by means of ultrasonic inspection. Results of the analysed defect configurations indicate that the influence of gap defects is only relevant under small impact energy values. However, in the case of damage tolerance, the residual compressive strength after impact does not present significant differences to that of conventional straight fibre laminates. This indicates that the strength reduction is driven mainly by the damage caused by the impact event rather than by the influence of manufacturing-induced defects

Variable-stiffness composite panels: Defect tolerance under in-plane tensile loading

Automated Fiber Placement is being extensively used in the production of major composite components for the aircraft industry. This technology enables the production of tow-steered panels, which have been proven to greatly improve the structural efficiency of composites by means of in-plane stiffness variation and load redistribution. However, traditional straight-fiber architectures are still preferred. One of the reasons behind this is related to the uncertainties, as a result of process-induced defects, in the mechanical performance of the laminates. This experimental work investigates the effect of the fiber angle discontinuities between different tow courses in a ply on the un-notched and open-hole tensile strength of the laminate. The influence of several manufacturing parameters are studied in detail. The results reveal that 'ply staggering' and '0% gap coverage' is an effective combination in reducing the influence of defects in these laminates

Gridifying IBM's Generic Log Adapter to Speed-Up the Processing of Log Data

Peer-reviewed

Social Preferences and Transport Policy: The case of US speed limits

This article, in reviewing the longrunning US debate on speed limits, illustrates how a different valuation of the trade-off between private mobility needs and safety concerns can shape transport policies. It is argued that the regulatory decentralization debate, together with the speed limit in force in each state, obey the social preferences and valuation given to this tradeoff. Such a view is consistent with evidence that higher speed limits are to be found in states with greater private mobility needs, even though their fatality rates might be among the highest in the country. By contrast, lower speed limits and supporters of a low national speed limit are to be found in states that show a greater concern for safety outcomes and which are less dependent on private mobility. By reviewing these events and examining the role played by the main actors and analyzing their motivations, the article identifies important lessons for similar future discussions on transport policy.

Regulating Concessions of Toll Motorways, An Empirical Study on Fixed vs. Variable Term Contracts

Recent theoretical developments on concession contracts for long term infrastructure projects under uncertain demand show the benefits of allowing for flexible term contracts rather than fixing a rigid term. This study presents a simulation to compare both alternatives by using real data from the oldest Spanish toll motorway. For this purpose, we analyze how well the flexible term would have performed instead of the fixed length actually established. Our results show a huge reduction of the term of concession that would have dramatically decreased the firm’s benefits and the user’s overpayment due to the internalization of an unexpected traffic increase.

Regression analysis of compositional data when both the dependent variable and independent variable are components

It is well known that regression analyses involving compositional data need special attention because the data are not of full rank. For a regression analysis where both the dependent and independent variable are components we propose a transformation of the components emphasizing their role as dependent and independent variables. A simple linear regression can be performed on the transformed components. The regression line can be depicted in a ternary diagram facilitating the interpretation of the analysis in terms of components. An exemple with time-budgets illustrates the method and the graphical features

Primer "speed net-working" a la Facultat de Farmàcia de la Universitat de Barcelona

Un dels objectius plantejats pel Comissionat per a la Participació, Ocupabilitat i Emprenedoria Social de la Universitat de Barcelona és desenvolupar, conjuntament amb els centres i les facultats, estratègies i accions encaminades a millorar l’ocupabilitat i la inserció laboral i professional d’estudiants i egressats. A més, l’ equip deganal de la Facultat de Farmàcia té com a una de les seves prioritats implementar accions per a la Millora de les competències professionals dels estudiants del Grau de Farmàcia.

Primer "speed net-working" a la Facultat de Farmàcia de la Universitat de Barcelona

Un dels objectius plantejats pel Comissionat per a la Participació, Ocupabilitat i Emprenedoria Social de la Universitat de Barcelona és desenvolupar, conjuntament amb els centres i les facultats, estratègies i accions encaminades a millorar l’ocupabilitat i la inserció laboral i professional d’estudiants i egressats. A més, l’ equip deganal de la Facultat de Farmàcia té com a una de les seves prioritats implementar accions per a la Millora de les competències professionals dels estudiants del Grau de Farmàcia.

Primer "speed net-working" a la Facultat de Farmàcia de la Universitat de Barcelona

Un dels objectius plantejats pel Comissionat per a la Participació, Ocupabilitat i Emprenedoria Social de la Universitat de Barcelona és desenvolupar, conjuntament amb els centres i les facultats, estratègies i accions encaminades a millorar l’ocupabilitat i la inserció laboral i professional d’estudiants i egressats. A més, l’ equip deganal de la Facultat de Farmàcia té com a una de les seves prioritats implementar accions per a la Millora de les competències professionals dels estudiants del Grau de Farmàcia.

An Interface Damage Model for the Simulation of Delamination Under Variable-Mode Ratio in Composite Materials

A thermodynamically consistent damage model for the simulation of progressive delamination under variable mode ratio is presented. The model is formulated in the context of the Damage Mechanics. The constitutive equation that results from the definition of the free energy as a function of a damage variable is used to model the initiation and propagation of delamination. A new delamination initiation criterion is developed to assure that the formulation can account for changes in the loading mode in a thermodynamically consistent way. The formulation proposed accounts for crack closure effets avoiding interfacial penetration of two adjacent layers aftercomplete decohesion. The model is implemented in a finite element formulation. The numerical predictions given by the model are compared with experimental results

Approximate solution to the speed of spreading viruses

Recently, it has been shown that the speed of virus infections can be explained by time-delayed reactiondiffusion [J. Fort and V. Me´ndez, Phys. Rev. Lett. 89, 178101 (2002)], but no analytical solutions were found. Here we derive formulas for the front speed, valid in appropriate limits. We also integrate numerically the evolution equations of the system. There is good agreement with both numerical and experimental speeds

Speed of travelling fronts: Two-dimensional and ballistic dispersal probability distributions

The speed of traveling fronts for a two-dimensional model of a delayed reactiondispersal process is derived analytically and from simulations of molecular dynamics. We show that the one-dimensional (1D) and two-dimensional (2D) versions of a given kernel do not yield always the same speed. It is also shown that the speeds of time-delayed fronts may be higher than those predicted by the corresponding non-delayed models. This result is shown for systems with peaked dispersal kernels which lead to ballistic transport