Structural behaviour of prestressed concrete sleepers produced with high performance recycled aggregate concrete

The final publication is available at Springer via http://dx.doi.org/10.1617/s11527-016-0966-6A comparative analysis of the structural behaviour of prestressed concrete sleepers made with high performance concrete (HPC) and high performance recycled aggregate concrete (HPRAC) is presented in this study. Two types of HPRAC sleepers were tested, using 50 and 100% of recycled concrete aggregate (RCA) in replacement of coarse natural aggregates. The RCA employed in this research was sourced from crushing rejected HPC sleepers. The aim of this study was to determine through analysis if the HPRAC sleepers’ behaviour fulfilled the European minimum requirements standards for prestressed concrete sleepers and compare their experimental behaviour with that of the HPC sleepers. The three types of prestressed concrete sleepers were subjected to static load tests at rail-seat and centre section (positive and negative load). In the centre section tests a comparative study between the experimental results and the proposed values of four assessment methods of ultimate capacity was carried out. Dynamic load and fatigue tests were also performed at the rail-seat section. The HPRACs and HPC sleepers met all the structural requirements for prestressed concrete sleepers. The experimental results determined the satisfactory performance of the HPRAC-50 and the HPRAC-100, which was very similar to that of the HPC sleepers. The load–strain behaviour recorded via the use of strain gauges on the prestressing bars revealed slightly higher stiffness of the HPC sleepers. The values obtained from the four assessment methods of ultimate capacity were also accurate when applied to HPRAC.Peer ReviewedPostprint (author's final draft

Level design: resources and techniques to guide the player

Video Games try to immerse the player in the world they present, graphical fidelity, music, sound, and gameplay are essential parts to achieve this objective, but sometimes the User Interface(UI) gets in the way, making the player feel that they are just playing a game, that there’s nothing deeper in the experience. A big part of the usual UI elements used by video games are focused on helping the player navigate through the environment, making the experience much more fluid as the player won’t get lost. There are techniques and resources that can be used in level design to avoid using as much UI elements, there is a good amount of documentation about this elements, but the information is dispersed in many books, thesis, papers, and videos. This thesis presents an ordered list of the most used and effective resources, together with the analysis and playtesting of 2 levels from 2 different games. The list gives the toolkit required to build a level, the analysis verify the effectivity of some of the resources

A quantum walk simulation of extra dimensions with warped geometry

We investigate the properties of a quantum walk which can simulate the behavior of a spin $1/2$ particle in a model with an ordinary spatial dimension, and one extra dimension with warped geometry between two branes. Such a setup constitutes a $1+1$ dimensional version of the Randall-Sundrum model, which plays an important role in high energy physics. In the continuum spacetime limit, the quantum walk reproduces the Dirac equation corresponding to the model, which allows to anticipate some of the properties that can be reproduced by the quantum walk. In particular, we observe that the probability distribution becomes, at large time steps, concentrated near the "low energy" brane, and can be approximated as the lowest eigenstate of the continuum Hamiltonian that is compatible with the symmetries of the model. In this way, we obtain a localization effect whose strength is controlled by a warp coefficient. In other words, here localization arises from the geometry of the model, at variance with the usual effect that is originated from random irregularities, as in Anderson localization. In summary, we establish an interesting correspondence between a high energy physics model and localization in quantum walks.Comment: 16 pages, 8 figure

Sistema de becas y equidad participativa en la universidad

El objetivo del artículo es analizar el impacto del aumento de tasas universitarias del 66% que se implementó en Cataluña en el cuso 2012-13 y el papel de las becas provenientes del gobierno central. Se analizan los datos de los estudiantes de nuevo acceso de dos universidades catalanas, considerando clase social, titulación elegida y solicitud de beca, y se compara el año anterior y posterior al aumento de las tasas. Se constata cómo hay una diferente composición social en las diferentes titulaciones según coste de la matrícula y dificultad de superar los créditos. Así se muestra una estratificación en las universidades analizadas y un aumento de ésta en los cursos analizados, alejando así el sistema universitario de la equidad participativa de los estudiantes

Single-Trial Recognition of Video Gamer’s Expertise from Brain Haemodynamic and Facial Emotion Responses

With an increase in consumer demand of video gaming entertainment, the game industry is exploring novel ways of game interaction such as providing direct interfaces between the game and the gamers’ cognitive or affective responses. In this work, gamer’s brain activity has been imaged using functional near infrared spectroscopy (fNIRS) whilst they watch video of a video game (League of Legends) they play. A video of the face of the participants is also recorded for each of a total of 15 trials where a trial is defined as watching a gameplay video. From the data collected, i.e., gamer’s fNIRS data in combination with emotional state estimation from gamer’s facial expressions, the expertise level of the gamers has been decoded per trial in a multi-modal framework comprising of unsupervised deep feature learning and classification by state-of-the-art models. The best tri-class classification accuracy is obtained using a cascade of random convolutional kernel transform (ROCKET) feature extraction method and deep classifier at 91.44%. This is the first work that aims at decoding expertise level of gamers using non-restrictive and portable technologies for brain imaging, and emotional state recognition derived from gamers’ facial expressions. This work has profound implications for novel designs of future human interactions with video games and brain-controlled games

Análisis del artículo de investigación de marketing: Características propias

Los investigadores del área de marketing de las universidades españolas tienen una especial preferencia por la publicación de sus artículos en revistas internacionales. La lengua utilizada en la mayoría de estas revistas es el inglés, lo que frecuentemente supone una dificultad añadida para estos investigadores puesto que no es sólo lacalidad de la investigación lo que van a valorar los evaluadores de las revistas, sino también la adecuada utilización de la lengua inglesa. Por esta razón, el análisis del inglés académico utilizado en los artículos de investigación se ha convertido en un campo de investigación tanto para el área de marketing e investigación de mercados, como para la de filología inglesa. El objetivo de este artículo es identificar los rasgos específicos y diferenciadores de los artículos de marketing, en una investigación conjunta de profesores de las dos áreas mencionadas

Solitons in a photonic nonlinear quantum walk: lessons from the continuum

We analyse a nonlinear QW model which can be experimentally implemented using the components of the electric field on an optical nonlinear Kerr medium, which translates into a rotation in the coin operator, with an angle which depends (in a nonlinear fashion) on the state of the walker. This simple dependence makes it easy to consider the space-time continuum limit of the evolution equation, which takes the form of a nonlinear Dirac equation. The analysis of this continuum limit allows us, under some approximations, to gain some insight into the nature of soliton structures, which is illustrated by our numerical calculations. These solitons are stable structures whose trajectories can be modulated by choosing the appropriate initial conditions. We have also studied the stability of solitons when they are subject to an additional phase that simulates an external electric field, and also explored if they are formed in higher dimensional spaces

The cosmological bias factor of damped Lyman alpha systems: dependence on metal line strength

We measure the cosmological bias factor of damped Ly α absorbers (DLAs) from their crosscorrelation with the Ly α forest absorption, as a function of the DLA metal strength, defined from an average of equivalent widths of the strongest detectable low-ionization metal lines. A clear increase of the bias factor with metal strength is detected, as expected from a relation of metallicity and velocity dispersion with host halo mass. The relation is stronger after the metal strength is corrected for the H I column density, to make it more related to metallicity instead of metal column density. After correcting for the effects of measurement errors of the metal strength parameter, we find that the bias factor of DLAs with the weakest metal lines is close to unity, consistent with an origin in dwarf galaxies with host halo masses ∼1010M , whereas the most metal rich DLAs have a bias factor as large as bDLA ∼ 3, indicative of massive galaxies or galaxy groups in host haloes with masses ∼1012M . Our result confirms the physical origin of the relation of bias factors measured from cross-correlation studies to the host haloes of the absorbers