Motivación e intención de ser físicamente activo en adolescentes ecuatorianos y españoles

El propósito del estudio fue analizar el papel predictivo de las orientaciones motivacionales, motivación intrínseca, flow disposicional y gusto por la educación física sobre la intención de ser físicamente activo en una muestra de 1571 adolescentes, con una edad media de 13.98 años, escolarizados de Ecuador y España. Se realizó una regresión por pasos, resultando un modelo final de tres fases en el que el flow disposicional, la motivación intrínseca y el gusto por la educación física predecían la intención de seguir siendo físicamente activo en ambas poblaciones, justificando un 42% de la varianza en sujetos ecuatorianos y un 36% en españoles. Se discuten los resultados en relación a la importancia emergente del flow como variable predictiva de la práctica futura en relación con otras más estudiadas

Addicted to Punishment: The Disproportionality of Drug Laws in Latin America

In Latin America, trafficking cocaine so it can be sold to someone who wants to use it is more serious than raping a woman or deliberately killingyour neighbor. While it may seem incredible, that is the conclusion of arigorous study of the evolution of criminal legislation in the region, which shows that countries' judicial systems mete out harsher penalties for traffickingeven modest amounts of drugs than for acts as heinous as sexua lassault or murder.How have we reached such an unjust and irrational point? In recent decades, especially the 1980s, Latin American countries, influenced by aninternational prohibitionist model, fell -- ironically -- into what we mightmetaphorically call an addiction to punishment.Addiction creates the need to consume more and more drugs, whichhave less and less effect; ultimately, the problematic user simply consumesdrugs to avoid withdrawal. Drug legislation in Latin America seems to have followed a similar path. Countries have an ever-growing need to add crimes and increase the penalties for drug trafficking, supposedly to control an expanding illegal market, while this increasingly punitive approach has less and less effect on decreasing the supply and use of illegal drugs.This report explores whether the recent evolution of criminal legislation in Latin American countries with regard to drug-related conducts respects these minimal guarantees to which criminal law should be subject, and especially whether that criminal legislation can be considered proportionate to the harm caused by prohibited conducts. Ultimately, the question is whether the crimes and punishments outlined in national legislation are proportionate. If the answer is no, the conclusion should be that they may even be unconstitutional within the framework of a constitutional state.To address this question, the report explores the recent development of criminal laws on drug-related crime in seven Latin American countries: Argentina, Bolivia, Brazil, Ecuador, Colombia, Peru and Mexico. These countries were chosen based on two basic criteria. First, they are of academic importance, because they have different drug-related problems, different geographic locations, diverse contexts and different political systems. According to traditional categorization, Colombia, Peru and Bolivia are considered producer countries; Mexico and even Brazil are considered trans-shipment countries. They also represent the different regions of Latin America,from the Southern Cone to the furthest Spanish-speaking country in North America.This report has three main parts. The first provides a conceptual and methodological overview of the elements that form the basis of the analysis.The second describes the principal recent trends in criminal drug legislation in Latin America. The third analyzes the proportionality of drug-related crimes and punishment in the countries, comparing them with penalties for other serious crimes, followed by some conclusions

Toward a new generation of photonic devices based on the integration of metal oxides in silicon technology

[ES] La búsqueda de nuevas soluciones e ideas innovadoras en el campo de la fotónica de silicio mediante la integración de nuevos materiales con prestaciones únicas es un tema de alta actualidad entre la comunidad científica en fotónica y con un impacto potencial muy alto. Dentro de esta temática, esta tesis pretende contribuir hacia una nueva generación de dispositivos fotónicos basados en la integración de óxidos metálicos en tecnología de silicio. Los óxidos metálicos elegidos pertenecen a la familia de óxidos conductores transparentes (TCO), concretamente el óxido de indio y estaño (ITO) y el óxido de cadmio (CdO), y materiales de cambio de fase (PCM) como el dióxido de vanadio (VO2). Dichos materiales se caracterizan especialmente por una variación drástica de sus propiedades optoelectrónicas, tales como la resistividad o el índice de refracción, frente a un estímulo externo ya sea en forma de temperatura, aplicación de un campo eléctrico o excitación óptica. De esta forma, nuestro objetivo es diseñar, fabricar y demostrar experimentalmente nuevas soluciones y dispositivos clave tales como dispositivos no volátiles, desfasadores y dispositivos con no linealidad óptica. Tales dispositivos podrían encontrar potencial utilidad en diversas aplicaciones que comprenden las comunicaciones ópticas, redes neuronales, LiDAR, computación, cuántica, entre otros. Las prestaciones clave en las que se pretende dar un salto disruptivo son el tamaño y capacidad para una alta densidad de integración, el consumo de potencia, y el ancho de banda.[CA] La recerca de noves solucions i idees innovadores al camp de la fotònica de silici mitjançant la integració de nous materials amb prestacions úniques és un tema d'alta actualitat entre la comunitat científica en fotònica i amb un impacte potencial molt alt. D'aquesta temàtica, aquesta tesi pretén contribuir cap a una nova generació de dispositius fotònics basats en la integració d'òxids metàl·lics en tecnologia de silici. Els òxids metàl·lics elegits pertanyen a la família d'òxids conductors transparents (TCO), concretament l'òxid d'indi i estany (ITO) i l'òxid de cadmi (CdO), i materials de canvi de fase (PCM) com el diòxid de vanadi (VO2). Aquests materials es caracteritzen especialment per una variació dràstica de les propietats optoelectròniques, com ara la resistivitat o l'índex de refracció, davant d'un estímul extern ja siga en forma de temperatura, aplicació d'un camp elèctric o excitació òptica. D'aquesta manera, el nostre objectiu és dissenyar, fabricar i demostrar experimentalment noves solucions i dispositius clau com ara dispositius no volàtils, desfasadors i dispositius amb no-linealitat òptica. Aquests dispositius podrien trobar potencial utilitat en diverses aplicacions que comprenen les comunicacions òptiques, xarxes neuronals, LiDAR, computació, quàntica, entre d'altres. Les prestacions clau en què es pretén fer un salt disruptiu són la grandària i la capacitat per a una alta densitat d'integració, el consum de potència i l'amplada de banda.[EN] The search for new solutions and innovative ideas in the field of silicon photonics through the integration of new materials featuring unique optoelectronic properties is a hot topic among the photonics scientific community with a very high potential impact. Within this topic, this thesis aims to contribute to a new generation of photonic devices based on the integration of metal oxides in silicon technology. The chosen metal oxides belong to the family of transparent conducting oxides (TCOs), namely indium tin oxide (ITO) and cadmium oxide (CdO), and phase change materials (PCMs) such as vanadium dioxide (VO2). These materials are characterized by a drastic variation of their optoelectronic properties, such as resistivity or refractive index, in response to an external stimulus either in the form of temperature, application of an electric field, or optical excitation. Therefore, our objective is to design, fabricate and experimentally demonstrate new solutions and key devices such as non-volatile devices, phase shifters, and devices with optical nonlinearity. Such devices could find potential utility in several applications, including optical communications, neural networks, LiDAR, computing, and quantum. The key features in which we aim to take a leapfrog are footprint and capacity for high integration density, power consumption, and bandwidth.This work is supported in part by grants ACIF/2018/172 funded by Generaliltat Valenciana, and FPU17/04224 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”.Parra Gómez, J. (2022). Toward a new generation of photonic devices based on the integration of metal oxides in silicon technology [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/19088

RESTful framework for collaborative internet of things based on IEC 61850

El contenido de los capítulos 2 y 3 está sujeto a confidencialidad 161 p.En 1991, Mark Weiser formuló el paradigma de Computación Ubicua definiendo el concepto de Entorno Inteligente como un espacio físico repleto de dispositivos, muy integrados en el entorno, y con capacidades de identificación, sensorización y actuación. Internet de las Cosas (IoT) expande el ámbito de localización de estos dispositivos y servicios ubicuos, representados como cosas, de un entorno local a internet como red global. Para la implementación de estos escenarios de aplicación, la colaboración entre las cosas es uno de los principales retos de investigación. El objetivo de esta colaboración es ser capaces de satisfacer necesidades globales mediante la combinación de servicios individuales. Esta Tesis propone una arquitectura colaborativa entre las cosas desplegadas en internet.Las tecnologías alrededor de los Servicios Web SOAP/XML, adecuadas para IoT, soportan aspectos claves para un sistema colaborativo como la publicación, descubrimiento, control y gestión de eventos de los dispositivos. Como alternativa, REST ha ganado terreno en este ámbito por ser considerada una opción más ligera, sencilla y natural para la comunicación en internet. Sin embargo, no existen protocolos para descubrimiento y gestión de eventos para recursos REST. Esta Tesis aborda dicha carencia proponiendo una especificación de estos protocolos para arquitecturas REST. Otro aspecto importante es la representación, a nivel de aplicación, de las cosas distribuidas. Entre las propuestas para la estandarización de los modelos de información y comunicación en este dominio que podrían aplicarse, de manera similar, a IoT, destaca el estándar IEC 61850. Sin embargo, los protocolos de comunicación definidos por el estándar no son adecuados para IoT. Esta Tesis analiza la idoneidad del IEC 61850 para escenarios IoT y propone un protocolo de comunicación REST para sus servicios.Por último, se trata la problemática asociada a la confiabilidad que debe proporcionar una arquitectura IoT para dominios de aplicación relacionados con la salud o sistemas de seguridad funcional (Safety)

On content-based recommendation and user privacy in social-tagging systems

Recommendation systems and content filtering approaches based on annotations and ratings, essentially rely on users expressing their preferences and interests through their actions, in order to provide personalised content. This activity, in which users engage collectively has been named social tagging, and it is one of the most popular in which users engage online, and although it has opened new possibilities for application interoperability on the semantic web, it is also posing new privacy threats. It, in fact, consists of describing online or offline resources by using free-text labels (i.e. tags), therefore exposing the user profile and activity to privacy attacks. Users, as a result, may wish to adopt a privacy-enhancing strategy in order not to reveal their interests completely. Tag forgery is a privacy enhancing technology consisting of generating tags for categories or resources that do not reflect the user's actual preferences. By modifying their profile, tag forgery may have a negative impact on the quality of the recommendation system, thus protecting user privacy to a certain extent but at the expenses of utility loss. The impact of tag forgery on content-based recommendation is, therefore, investigated in a real-world application scenario where different forgery strategies are evaluated, and the consequent loss in utility is measured and compared.Peer ReviewedPostprint (author’s final draft

Shall I post this now? Optimized, delay-based privacy protection in social networks

The final publication is available at Springer via http://dx.doi.org/10.1007/s10115-016-1010-4Despite the several advantages commonly attributed to social networks such as easiness and immediacy to communicate with acquaintances and friends, significant privacy threats provoked by unexperienced or even irresponsible users recklessly publishing sensitive material are also noticeable. Yet, a different, but equally significant privacy risk might arise from social networks profiling the online activity of their users based on the timestamp of the interactions between the former and the latter. In order to thwart this last type of commonly neglected attacks, this paper proposes an optimized deferral mechanism for messages in online social networks. Such solution suggests intelligently delaying certain messages posted by end users in social networks in a way that the observed online activity profile generated by the attacker does not reveal any time-based sensitive information, while preserving the usability of the system. Experimental results as well as a proposed architecture implementing this approach demonstrate the suitability and feasibility of our mechanism.Peer ReviewedPostprint (author's final draft

Online advertising: analysis of privacy threats and protection approaches

Online advertising, the pillar of the “free” content on the Web, has revolutionized the marketing business in recent years by creating a myriad of new opportunities for advertisers to reach potential customers. The current advertising model builds upon an intricate infrastructure composed of a variety of intermediary entities and technologies whose main aim is to deliver personalized ads. For this purpose, a wealth of user data is collected, aggregated, processed and traded behind the scenes at an unprecedented rate. Despite the enormous value of online advertising, however, the intrusiveness and ubiquity of these practices prompt serious privacy concerns. This article surveys the online advertising infrastructure and its supporting technologies, and presents a thorough overview of the underlying privacy risks and the solutions that may mitigate them. We first analyze the threats and potential privacy attackers in this scenario of online advertising. In particular, we examine the main components of the advertising infrastructure in terms of tracking capabilities, data collection, aggregation level and privacy risk, and overview the tracking and data-sharing technologies employed by these components. Then, we conduct a comprehensive survey of the most relevant privacy mechanisms, and classify and compare them on the basis of their privacy guarantees and impact on the Web.Peer ReviewedPostprint (author's final draft