2,338 research outputs found
Contribuição para o estudo da incorporação de materiais poliméricos em membranas betuminosas
A realização deste trabalho inseriu-se na contribuição para o estudo da incorporação de novos materiais poliméricos em membranas betuminosas, mais concretamente na modificação de misturas betuminosas. Para o efeito, foram sintetizados novos poliésteres polióis semelhantes estruturalmente, mas com diferentes pesos moleculares, baseados na utilização de ácidos diméricos de fonte renovável (tall-oil), que serviram de suporte para a produção de prepolímeros de isocianato para a modificação de betumes. A caracterização dos póliesteres polióis e dos polímeros produzidos foi realizada através de espectroscopia de infravermelhos.
Ensaios de engenharia e qualidade, especificados para misturas betuminosas, foram realizados a diversos betumes convencionais e modificados, nos laboratórios industriais das empresas Imperalum e Probigalp como parte integrante no conhecimento dos procedimentos para este tipo de ensaios, nomeadamente o ensaio de penetração, ponto de amolecimento, viscosidade cinemática e dinâmica, apoiando igualmente um estudo de reprodutibilidade inter-laboratorial.
Betumes 160/220 previamente modificados com teores de 1% e 3% de prepolímeros reactivos e, modificados com APP e SBS, foram caracterizados reologicamente a várias temperaturas na zona de viscoelasticidade linear. Os ensaios foram realizados em regime dinâmico através do varrimento em frequência a várias temperaturas. Pela análise dos resultados obtidos, concluiu-se que as modificações consideradas aumentam o carácter elástico dos betumes, confirmado pelo aumento do módulo elástico (G’(ω)).
Os betumes modificados com teores de 1% de prepolímeros foram caracterizados microestruturalmente através de microscopia de força atómica. As imagens topográficas obtidas confirmam a existência de três fases distintas, designadamente a fase catana, perifase e parafase. A avaliação das proporções de cada fase revelou dependências entre a estrutura dos modificadores e a alteração efectiva da microestrutura dos betumes
Place Change and Identity Processes.
This study intents to examine the relationship between place
change and identity process, using Breakwell’s model (1986,
1992) as framework. In the context of a process of imposed
relocation in an old neighbourhood in Lisbon, two groups of
residents were studied in two different moments along the
relocation process. These two groups differ in terms of their choice
of relocation. The generic hypothesis of the study is that relocation,
and the residents’ choice changes the relation of the people with
the space, the social relationships, and it has also an impact in the
resident’s identity. The results show that the relocation process
threats the identity principles in the two groups, but in different
ways, depending of the residential choice, and also had impact in
the social relationships and in the relation of the people with the
space. As other studies (e.g.: Twigger-Ross and Uzzell, 1996;
Speller, Lyons, and Twigger-Ross, 2002) this research underlines
the relationship between changes in physical environment and
identity, in the context of residential environment
Urban neighbourhoods and intergroup relations: The importance of place identity
The aim of this paper is to bring the concept of place identity into the context of intergroup relationships
in urban place, using the social identity approach. A field study was conducted in four adjacent neighbourhoods
in the city of Lisbon, in order to explore the influence of place identity on the perception of
the participants’ own neighbourhood and its residents (in-group) and of the other neighbourhoods and
their residents (out-groups). The results showed that place identity was highly correlated with neighbourhood
satisfaction, relevant out-group differentiation, and favouritism to the in-group and depreciation
of the relevant out-group. The results also enabled the identification of three types of possible
relationships between the groups: a relevant out-group for comparison, an idealized reference group for
approximation, and a devaluated group for avoidance. Moreover, in this study, we extend the predictions
of SIA to the comprehension of specific distance estimation distortion patterns
Sagnac loop in ring resonators for tunable optical filters
General filter architecture using co- and counterpropagation signals are studied. A specific configuration based on a Sagnac loop within a ring resonator is analyzed. Novel tuning, apart from conventional tuning, is achieved by changing the coupling ratio of a coupler through the adjustment of the equivalent loop length. Full equations describing the filter behavior in passive and active configurations, and simple closed-form formulas to compute the tuning, tolerance, and full-width at half-maximum are reported. The performance of these devices is discussed for their application as selective or channel-dropping ultra-narrow-band filters. The effect of losses and their dispersion properties are also discussed. These devices can be conveniently implemented, using silicon- or InP-integrated optic technology, for they have high free spectral ranges.Publicad
Tunable Optical Filters Using Compound Ring Resonators for DWDM
The device is based on a loop mirror in a ring resonator. The loop mirror allows tuning by changing the coupling coefficient of a directional coupler. The loop mirror is implemented using a Sagnac configuration to have the same optical path between the signals to be interfered (copropagating and counterpropagating ones). The filter structure allows optical integration for having higher free-spectral ranges. Simple design equations for the filter parameters and the tuning are reported. Measurements on a passive optical fiber tunable filter are presented. There is a good agreement between measurements and theory.Publicad
Measurements On Passive Tunable Optical Filters For DWDM
WFOPC 2002 IEEE/LEOS Workshop on Fibre and Optical Passive Components, University of Glasgow, Scotland, on 5th-6th June 2002.Measurements on a passive optical fibre tunable filter are presented. The device is based on a loop mirror in a ring resonator. The loop mirror allows tuning by changing the coupling coefficient of a coupler. The novel filter structure allows planar optical integration for having higher free spectral ranges. Novel and simple design equations for the filter parameters and the tuning process are reported. There is a good agreement between measurements and theory.Universidad Carlos III de MadridPublicad
Soluções de controlo de dispositivos para automação residencial
Nos últimos anos temos assistido ao aparecimento de novos dispositivos inteligentes
e sistemas de automação residencial. Com o objetivo de conectar e controlar equi-
pamentos eletrónicos, dentro de uma habitação, existe a necessidade de desenvolver
soluções integradas de controlo remoto. Os smartphones, apresentam todas as carac-
terísticas, poder computacional e portabilidade, ideais para controlo e monitorização
deste tipo de dispositivos. Quando se considera o desenvolvimento de um produto novo
e dependendo do problema, escolher a abordagem e tecnologias mais adequadas nem
sempre é fácil.
Este projeto apresenta um conjunto de tecnologias e soluções de controlo baseadas
em arquiteturas móveis. Para prova de conceito, e baseado num sistema real (IVIT),
é proposta uma solução inovadora usando um smartphone. O IVIT, desenvolve uma
tecnologia para aplicar num reservatório de aquecimento de água de inércia variável,
com funcionalidades de monitorização, controlo e operação colaborativa do sistema de
aquecimento.
Os resultados obtidos comprovaram que o desempenho da aplicação ultrapassou
as expectativas e que a solução proposta é uma alternativa viável para o controlo de
dispositivos para automação residencial usando smartphones
SEMINARIO SOBRE PROCEDIMIENTOS OPERATIVOS ESTANDARIZADOS Y RESPONSABILIDAD PENAL DE LA PERSONA JURÍDICA
Esta publicación recoge las principales conclusiones alcanzadas en el Seminario sobre "PROCEDIMIENTOS OPERATIVOS ESTANDARIZADOS Y RESPONSABILIDAD PENAL DE LA PERSONA JURÍDICA" celebrado en la Universidad de Córdoba durante los días 20 y 21 de junio de 2013 en el marco del Proyecto de Investigación DER2010-16569 del Ministerio de Economía y Competitividad. Se analizan cuestiones que van desde el modelo de responsabilidad para la persona jurídica que recoge nuestro vigente Código Penal o el papel que juegan los programas de cumplimiento en un modelo vicarial, hasta el análisis y realización de propuestas interpretativas respecto de distintas cuestiones que sobre esta materia plantea la reforma del Código Penal en tramitación: situaciones que quedan abarcadas por los hechos de conexión, deber de control, mapas de riesgos, órganos de control, etc
Technological tools applied to the knowledge and application of criminal law
Se trata de una experiencia con la que se pretende formar al alumno en el uso de las nuevas herramientas tecnológicas que permiten el acceso a las interpretaciones aplicativas que la jurisprudencia viene haciendo de los conceptos básicos de la disciplina penal, conceptos previamente seleccionados por el profesorado como parte del proyecto docente. Mediante el trabajo en grupos de tamaño reducido, los alumnos construyen el contenido de tales conceptos a partir del análisis y discriminación de las posiciones jurisprudenciales que encuentran utilizando diversos recursos electrónicos, consiguiendo, de esta forma, mejorar su proceso de aprendizaje en dos aspectos sustanciales: 1) facilitándoles la comprensión de los conceptos esenciales de la disciplina y de los problemas aplicativos que plantean y 2) ayudándoles a superar la fractura existente entre la teoría que se imparte a lo largo de la carrera y la realidad a la que tiene que hacer frente el profesional. Los resultados positivos alcanzados hacen de éste un método de trabajo altamente recomendable en disciplinas que forman parte de lo que se denomina “Derecho positivo” que, por estar sujetas a continuos cambios normativos, requieren del profesional del Derecho un proceso de constante actualización y puesta al día en sus conocimientos.This project is an experience that aims to train students in the use of new technological tools, which allow them to know the jurisprudential interpretation of the basic concepts of criminal law. The students, working in small groups and using electronic resources, build those concepts by detecting and analyzing the jurisprudential positions. In this way, students manage to improve their learning process in two key aspects: 1) getting a better understanding of the key concepts of the field and their application problems, and 2) being helped to overcome the existing fracture between the theoretical knowledge and the practical application of the law. This method of working is highly recommended for the Law, given the positive results obtained, particularly for those legal disciplines, which are constantly changing and that require from professionals a lifelong updating
Influence of leading edge imperfections on the aerodynamic characterictics of NACA 632-215 laminar aerofoils at low Reynolds number
This article deals with the effect of leading edge imperfections on the aerodynamic characteristics of a NACA 632-215 laminar aerofoil at low Reynolds numbers. Wind tunnel tests have been performed at different Reynolds numbers and angles of attack and global aerodynamic loads were measured. To perform these tests, a NACA 632-215 aerofoil was built up in two halves (corresponding to the upper side and to the lower side), the leading edge imperfection here considered being a slight displacement of half aerofoil with respect to the other. From experimental results, a quantitative measure of the influence of the leading edge displacement on the degradation of the aerofoil aerodynamic performances has been obtained. This allows the establishment of a criterion for an acceptance limit for this kind of imperfectio
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