Uranium minerals from the Picoto uranium mine area (Central Portugal)

Uranium minerals from the Picoto uranium mine area (Central Portugal

Redes pedonais para pessoas com mobilidade reduzida : exercício de avaliação multicritério em Braga, Portugal

A mobilidade urbana é um fator primordial para os planeadores urbanos e decisores no desenvolver da sua atividade, principalmente quando esta tem como objeto as viagens da população com mobilidade reduzida. No âmbito da realidade portuguesa, o presente trabalho avaliou se as características físicas de um determinado espaço urbano respeitam as exigências do Decreto-Lei 163/2006. Neste enquadramento foi idealizado um modelo de avaliação multicritério do grau de conformidade dos espaços. De acordo com as normas vigentes foi gerada uma classificação dos locais estudados. Este modelo integra a normalização das medições efetuadas para os itens considerados e a sua agregação, gerando um índice que exprime o grau de conformidade do local avaliado. O modelo foi implementado em ambiente SIG para permitir a representação dos resultados alcançados em mapas e aplicado a um caso de estudo na cidade de Braga, Portugal.Mobility is pointed as a key issue to urban planners and managers, especially when dealing with the mobility of pedestrians with mobility constraints. The goal of the present work is to analyze factors that limit the circulation of people with mobility constraints and to map those conditions in central urban spaces. Taking into account only the physical characteristics of urban spaces, the assessment is performed in agreement with the standards specified in the Portuguese Law. A multi-criteria model was developed to evaluate the compliance of urban spaces with those standards. Its integration within a GIS platform was performed, enabling a spatial analysis of the results. A case study was conducted in a central area of the city of Braga, Portugal. Maps showing levels of compliance with the standards were produced and the results were discussed

Pedestrian mobility : mapping circulation conditions for people with mobility constraints in a central urban area

Nowadays, pedestrian mobility is regarded as a key issue to urban planners since several studies have pointed it as an influential factor to the quality of life in central city areas. Consequently, walking conditions must be evaluated and some measures should be taken whenever the results show inappropriate implementations. This concern increases when focusing on the movement of people with mobility constraints, because for them a physical obstacle can represent an insurmountable obstruction. The goal of the present work is to analyze factors that limit the circulation of people with mobility constraints and to map those conditions in central urban areas. Taking into account only the physical characteristics of urban spaces, the assessment is performed in agreement with the standards specified in the Portuguese Law, defined by Decree-Law Nr 163/2006, in short DL 163/2006. The first part of the work introduces a multi-criteria model developed to evaluate the compliance of urban spaces with those standards. This model defines the normalization of measured values for each considered criterion, as well as their aggregation to achieve an index that expresses the compliance level of the evaluated urban spaces. The integration of the model within a GIS platform was performed in order to implement a spatial analysis of the results. The second part shows and discusses the results of a case study in a central area of the city of Braga, Portugal. The chosen area allows for the analysis of sidewalks and crosswalks of streets as a continuous network. Some sidewalk segments constructed before the approval of this law were also included allowing a comparative analysis with new (or improved) segments. The map of results highlights the sidewalk segments with worst performance, reflecting lower index values. This map is very helpful to city managers when identifying critical areas that require an intervention in order to improve the mobility of those pedestrians. Moreover, the proposed model can be easily adapted for other cities and countries

A multicriteria model for evaluating conformity of travelling conditions for pedestrians with mobility constraints

For people with mobility constraints, the conditions offered by pedestrian environments are crucial for their ability to remain independent and self-sufficient. Mobility is also a key factor to maintain people actively involved in the community. Taking into account only the physical characteristics of urban spaces, the goal of the present work is to analyse the factors that limit the circulation of people with mobility constraints and to map those conditions in central urban spaces. The assessment was performed in agreement with the standards specified in the Portuguese Law. A multi-criteria model was developed to evaluate the compliance of urban spaces with those standards. Its integration within a GIS platform was performed in order to implement a spatial analysis of the results. A case study was conducted in a central area of the city of Braga, Portugal. Maps showing levels of compliance with the standards were produced and the results are discussed.(undefined

Cadomian magmatism and metamorphism at the Ossa Morena/Central Iberian zone boundary, Iberian Massif, Central Portugal: Geochemistry and P–T constraints of the Sardoal Complex

ABSTRACT: A well preserved Cadomian basement is exposed in the Iberian Massif, Central Portugal, at the Ossa Morena/Central Iberian zone boundary, which allows the determination of reliable geochemical data. A sequence of Cadomian and Variscan magmatic and tectonometamorphic events has been already described for this area and are documented in other areas of the Avalonian-Cadomian orogen. However, the geochemical information concerning the Cadomian basement for this area is still limited. We present whole rock geochemical and oxygen isotopic information to characterize the igneous protoliths of the Sardoal Complex, located within the Tomar-Badajoz-Cordoba Shear Zone, and identify their tectonic setting. We use detailed petrography, mineral chemistry and P-T data to characterize the final Cadomian tectonometamorphic event. The Sardoal Complex contains orthogneiss and amphibolite units. The protoliths of the orthogneiss are calc-alkaline magmas of acid composition and peraluminous character that were generated in an active continental margin in three different stages (ca. 692 Ma, ca. 569 Ma and ca. 548 Ma). The most significant processes in their petrogenesis are the partial melting of old metasedimentary and meta-igneous crust at different crustal levels and the crystal fractionation of plagioclase, alkali feldspars, apatite, zircon and Fe-Ti oxides. The protoliths of the amphibolite, older than ca. 540 Ma, are tholeiitic and calc-alkaline magmas of basic composition that display N-,T- and E-MORB affinities. They were generated in an active continental margin. Crustal contamination and fractional crystallization of hornblende and diopside were involved in their petrogenesis. However, the fractional crystallization was not significant. The magmatic activity recorded in the Sardoal Complex indicates the existence of a long-lived continental arc (ca. 692-540 Ma) with coeval felsic and mafic magmatism. The final stage of the Cadomian metamorphism is usually represented in other areas of the Cadomian basement as a LP-HT metamorphic event. However, the P-T data obtained by thermodynamic modelling indicates medium pressure/high temperature conditions at ca. 540 Ma. These data suggest that the Sardoal Complex represents a deeper level of the exhumed Cadomian basement where the final stage of the Cadomian metamorphism was recorded.info:eu-repo/semantics/publishedVersio

Circulation environment in urban spaces for pedestrians with mobility constraints : a case study in Braga, Portugal

Mobility is pointed as a key issue to urban planners and managers. In particular the case of pedestrians with mobility constraints implies considering specific parameters. The goal of the present work is to analyse factors that limit the circulation of people with mobility constraints and to map those conditions in central urban spaces. Taking into account only the physical characteristics of urban spaces, the assessment is performed in agreement with the standards specified in the Portuguese Law. A multi-criteria model was developed to evaluate the compliance of urban spaces with those standards. Its integration within a GIS platform was performed in order to implement a spatial analysis of the results. A case study was conducted in a central area of the city of Braga, Portugal. Maps showing levels of compliance with the standards were produced and the results were discussed