Suchergebnisse

[ES] Los motores de encendido provocado (MEP) son una parte importante del mercado global del sector de la automoción. Uno de los principales inconvenientes de este tipo de combustión, es decir, MEP, es la variabilidad de ciclo a ciclo, que reduce la eficiencia de la combustión y restringe el avance máximo de la chispa debido a las limitaciones del knock. La dispersión de ciclo a ciclo está causada por fenómenos no observables en el momento, como el inicio de la combustión o la turbulencia alrededor de la chispa, y es un tema de interés en la investigación de modelado de motores. El trabajo presentado en este proyecto tiene como objetivo desarrollar un modelo orientado al control que sea capaz de reproducir, no solo el desarrollo de la combustión promedio, sino también la variabilidad de ciclo a ciclo. El modelo de combustión ha sido diseñado adaptando modelos publicados previamente basados ​​en la propagación de la llama. Las constantes de calibración principales se han identificado y se han implementado tablas de búsqueda para mejorar la precisión del modelo. La dispersión ciclo a ciclo se ha reproducido asumiendo una distribución de probabilidad inicial sobre la velocidad laminar y la turbulencia, que se propaga durante el desarrollo de la combustión. Las pruebas experimentales se han recogido en un motor comercial de última generación. Se ha utilizado un conjunto de datos de identificación y validación con variaciones de los actuadores principales, a saber, el avance de la chispa, la presión de admisión y la velocidad del motor. Los resultados muestran la capacidad del modelo para caracterizar con precisión la evolución de la combustión y reproducir la variabilidad ciclo a ciclo esperada. ; [EN] Spark ignited (SI) engines are becoming a significant part of the global market of the autmotive sector as Diesel engines are being restricted by new restringent legislations. One of the main drawbacks of this type of combustion, i.e. SI, is the cycle-to-cycle variability, which lower the combustion efficiency and ...

El art. 31.1 de la Constitución remite a un sistema tributario justo. Pero para apreciar la justicia del sistema hay que referirse a los principios legislativos, entre los que destaca el de seguridad jurídica. No es posible la justicia tributaria sin la seguridad jurídica. Y en un sistema de producción normativa desbocada como en el que vivimos, esa realización es muy difícil. La tesis trata de determinar si es posible controlar al legislador tributario, en cuanto a la cantidad de normas que produce, tanto legales como reglamentarias, y si los principios generales del Derecho y la seguridad jurídica en particular pueden ser instrumentos de control o límite para el legislador o regulador en general y tributario en particular. Se analiza cómo se entiende la seguridad jurídica por la doctrina y por la jurisprudencia del Tribunal Constitucional, analizando todas las sentencias dictadas que afectan a la seguridad jurídica de una u otra forma. Se determina cómo la seguridad jurídica afecta al sistema tributario y cómo afecta a la seguridad jurídica un sistema de producción normativa tributaria descontrolado. Se analiza la producción normativa tributaria con datos y cifras, desde 1990 a 2016, distinguiendo la producción legal o de rango equivalente y la producción reglamentaria e inferior, diferenciando ámbito territorial (estatal, autonómico, local, foral, europeo, internacional, el diferente rango normativo, así como la diferente regulación material por los tributos e impuestos afectados. Se analiza igualmente desde un punto de vista cuantitativo el diverso contenido tributario de la producción normativa, clasificando las normas según tengan un contenido tributario unívoco y propio (p. ej. la ley del impuesto sobre el valor añadido) o un contenido mixto, que incluye regulaciones de otros ámbitos junto al tributario (p. ej. las denominadas leyes ómnibus), o un contenido tributario accesorio, o incluso un contenido tributario oculto o "troyano". Se incluyen representaciones gráficas de la evolución de la producción normativa en materia tributaria, durante el período objeto de estudio. Una vez analizada la producción normativa concreta y específica, se determina cómo dicha producción afecta a la seguridad jurídica y se tratan de señalar los límites y posibles controles al abuso del legislador para la regulación normativa en este campo, tanto desde el punto de vista de "lege ferenda", como de "lege data", y tanto un control legislativo, "a priori" y "a posteriori", como jurisprudencial. ; 2017-18

Ethnography and cinema as meditation tools in gang research
In this article, Carles Feixa and José Sánchez-García share two main results of the Special Features of the TRANSGANG project: White Paper and Documentary films which looks at mediation tools in gang research. During the last five years, the TRANSGANG Project has investigated transnational gangs as agents of mediation in twelve cities of three regions: Southern Europe (Barcelona, Madrid, Marseille, Milano), Northern Africa (Rabat-Salé, Algiers, Djendel, Tunis), and the Americas (Medellin, San Salvador, Santiago de Cuba and Chicago). Among the main outcomes of the project, two special features have used ethnography and cinema as mediation tools in gang research.

TRANSGANG project, funding from the European Research Council (ERC) under the European Union's HORIZON 2020 research and innovation program under grant agreement No 742705

The 2011 Arab uprisings led to a great proliferation of studies on the situations in the Arab countries of the Mediterranean, with particular attention given to their young people, whose role was particularly central. Eight years on, in-depth exploration is still needed of the conditions in which millions of (mainly young) people demanded change. In this context, this volume examines the state and diversity of the forms of socioeconomic, political and cultural marginalization facing the region's young men and women, as well as the strategies and routes of contestation by which they escape them. Through the interdisciplinary empiricism of this book, based on the results emerging from the SAHWA Project (funded by the European Commission under the Seventh Framework Programme), we aspire to build a complex description and analysis of the current situation of the Arab Mediterranean youth. The aim is to fathom out young people's patterns, agency and living conditions, focusing on the relational character of the juvenile worlds actively constructed by themselves. The authors explore the main trends that are reflected in the social strategies, cultural constructions and changes within the Arab youth population, and whether the creation of new lifestyles and the emergence of youth cultures are an indicator of sociopolitical transitions. To answer all these questions the researchers have conducted a comprehensive study in five Arab Mediterranean countries: Algeria, Egypt, Lebanon, Morocco and Tunisia. Based on mixed method research the data collection is composed by two primary sources: the SAHWA Youth Survey 2016 (2017), 10,000 young people interviewed, and the SAHWA Ethnographic Fieldwork 2015, involving more than 200 young people.

The 2011 Arab uprisings led to a great proliferation of studies on the situations in the Arab countries of the Mediterranean, with particular attention given to their young people, whose role was particularly central. Eight years on, in-depth exploration is still needed of the conditions in which millions of (mainly young) people demanded change. In this context, this volume examines the state and diversity of the forms of socioeconomic, political and cultural marginalization facing the region's young men and women, as well as the strategies and routes of contestation by which they escape them. Through the interdisciplinary empiricism of this book, based on the results emerging from the SAHWA Project (funded by the European Commission under the Seventh Framework Programme), we aspire to build a complex description and analysis of the current situation of the Arab Mediterranean youth. The aim is to fathom out young people's patterns, agency and living conditions, focusing on the relational character of the juvenile worlds actively constructed by themselves. The authors explore the main trends that are reflected in the social strategies, cultural constructions and changes within the Arab youth population, and whether the creation of new lifestyles and the emergence of youth cultures are an indicator of sociopolitical transitions. To answer all these questions the researchers have conducted a comprehensive study in five Arab Mediterranean countries: Algeria, Egypt, Lebanon, Morocco and Tunisia. Based on mixed method research the data collection is composed by two primary sources: the SAHWA Youth Survey 2016 (2017), 10,000 young people interviewed, and the SAHWA Ethnographic Fieldwork 2015, involving more than 200 young people.

The concept of Mannheim generations, applied to the study of the Spanish social movements, allow to understand the differentiated readings that have been given on a concrete event (15M). These readings show the differences that are experienced within the post-15M social movements between agents and varied groups. In this work, as a case study we will analyze the participation of young people in the Platform of People Affected by the Mortgages of Lleida to understand their ways of understanding political activism and what relationship they have with their generation and the constitution of differentiated generational units. Through the realization of an ethnographic study (2014 to 2017), it has been possible to reconstruct the different historical formats that PAH has had from variables such as internal power relations, differentiated accumulations of militant capital among members and, by last and central in his work, of generational differentiations. As a result, two ways of understanding activist politics ‒reformist and rupturist‒ that coexist within the PAH and which, according to which of them have more power, condition their internal and external functioning, have been distinguished. Both positions have a clear relationship with the generational differentiation of the participants. ; El concepto de generaciones de Mannheim, aplicado al estudio de los movimientos sociales españoles, permiten comprender las lecturas diferenciadas que se han dado sobre un evento concreto (el 15M). Dichas lecturas muestran las diferenciaciones que se viven dentro de los movimientos sociales post-15M entre agentes y grupos variados. En este trabajo, como estudio de caso se analizará la participación de jóvenes en la Plataforma de Afectados por las Hipotecas de Lleida para comprender sus maneras de entender el activismo político y la qué relación tienen con su generación y la constitución de unidades generacionales diferenciadas. A través de la realización de un estudio etnográfico (2014 a 2017), se han podido reconstruir los diferentes formatos históricos que ha tenido la PAH a partir de variables como las relaciones de poder internas, las acumulaciones diferenciadas de capital militante entre miembros y, por último y central en este trabajo, de las diferenciaciones generacionales. Como resultado se han distinguido dos formas de entender la política activista ‒reformista y rupturista‒ que conviven en el interior de la PAH y que, según cual de ellas tiene más poder, condicionan su funcionamiento interno y externo. Ambas posturas tienen una clara relación con las diferenciaciones generacionales de los participantes.

Rap and mahragan were the sound of youths that demanded freedom and social justice in Tahrir Square and in Tunisia Parliament Square sit-ins during 2011. It may have been, not merely the soundtrack of the revolution, but a motivating factor in bringing people into the streets and reshaping their basic political subjectivity: a core process of any revolutionary change in a country's social and political structures. On the one hand, rap and mahragan are used by young people as a way of calling into question the processes of marginalization. On the other hand, young people use it as a way of participating in public life. Despite its differences, from a mixed analysis using the data collected in the SAHWA project, both qualitative and quantitative, this article proves how rap and mahragan music scenes (re)produce informal spaces as an alternative to their social marginalization and positioned them into Tunisian and Egyptian political arenas in different places according to environmental political dialectics.

Rap and mahragan were the sound of youths that demanded freedom and social justice in Tahrir Square and in Tunisia Parliament Square sit-ins during 2011. It may have been, not merely the soundtrack of the revolution, but a motivating factor in bringing people into the streets and reshaping their basic political subjectivity: a core process of any revolutionary change in a country's social and political structures. On the one hand, rap and mahragan are used by young people as a way of calling into question the processes of marginalization. On the other hand, young people use it as a way of participating in public life. Despite its differences, from a mixed analysis using the data collected in the SAHWA project, both qualitative and quantitative, this article proves how rap and mahragan music scenes (re)produce informal spaces as an alternative to their social marginalization and positioned them into Tunisian and Egyptian political arenas in different places according to environmental political dialectics. ; This article has received funding from the FP7 and from the European Research Council (ERC) under the European Union's HORIZON 2020 research and innovation programme under grant agreements No. 613174 and No. 742705.