Papers

In railways Ground Penetrating Radar (GPR) studies, the evaluation of materials dielectric properties is critical as they are sensitive to water content, to petrographic type of aggregates and to fouling condition of the ballast. Under the load traffic, maintenance actions and climatic effects, ballast condition change due to aggregate breakdown and to subgrade soils pumping, mainly on existing lines with no sub ballast layer. The main purpose of this study was to validate, under controlled conditions, the dielectric values of materials used in Portuguese railways, in order to improve the GPR interpretation using commercial software and consequently the management maintenance planning. Different materials were tested and a broad range of in situ conditions were simulated in laboratory, in physical models. GPR tests were performed with five antennas with frequencies between 400 and 1800 MHz. The variation of the dielectric properties was measured, and the range of values that can be obtained for different material condition was defined. Additionally, in situ GPR measurements and test pits were performed for validation of the dielectric constant of clean ballast. The results obtained are analyzed and the main conclusions are presented herein.

Adsorption kinetics is a key-issue for a successfulactivated carbon selection and design of the treatmentsystem. Crucial predictive aspects are the determination ofthe diffusion coefficients and the establishment of the controllingadsorption step. Several kinetic models have beendeveloped and two of the most frequently used, the homogeneoussurface diffusion model (HSDM) and the Boyd

The main objectives that generally motivate the implementation of energy management strategies, suggestions of possible assessment criteria and corresponding performance measures are presented in a systematic way. A methodology based on the hydraulic energy balance along waterpipe systems and four performance indices to assess energy efficiency is established. Thismethodology is applied to a real-life water supply system for two consumption scenarios and two operating schemes. The calculation of index E4 and the comparison between scenarios and schemes rely on the hydraulic simulation of the system. The application of this methodology has demonstrated the robustness and practicality of the proposed new performance indices, being particularly relevant for the comparison of different measures for the improvement of energy efficiency, such as the use of variable speed pumps and the installation of micro-turbines. More applications are needed forsystems with different sizes, layouts and elevations in order to identify and to overcome practical application difficulties.

This provides in a relative condensed format the results of small-scale study undertaken in Lisbon during the Meeting of the CyberParks Project (www.cost.eu/COST_Actions/tud/Actions/TU1306). CyberParks is a COST Action coordinated by the Universidade Lusófona at the CeiED - Interdisciplinary Research Centre for Education and Development. The Project aims at creating a research platform on the relationship between Information and Communication Technologies (ICT) and the production of public open spaces, and their relevance to sustainable urban development. The impacts of this relationship are being explored from social, ecological, urban design and technological perspectives. Based on the supposition that the participants of the Meeting are tourists visiting Lisbon, a survey was carried out on the topic how people actually use and how they would use public spaces. This survey is also the first approach to the case study areas chosen in Lisbon: Parque Quinta das Conchas and Jardim da Estrela. Both green spaces will be subject of further studies in the forthcoming years. This study employed (1) a questionnaire for measuring the user’s experience and preferences, and (2) two different tracking devices that utilise GNSS (Global Navigation Satellite Systems), in our case the GPS for satellite positioning technologies. It also presents the results of a study on the relevance of wi-fi in Lisbon’s public spaces. Even considering that the surveys in Lisbon’s green spaces are a first exercise within the work programme of CyberParks they show important outcomes. On the one hand, regarding the technologies used and their potential for research and on the other hand the findings about Lisbon’s green spaces. It should be noted that the conducted surveys and the gathered data are statistically not representative, but can be characterised as an empirical case and as a showcase, as how tourists tend to use a green space. The results shows that surveys benefit from multiple research methods and from combining insights.

Alkali–aggregate reactions have been known for decades although the acceptance of their occurrence has been delayed in some countries until the 1990s. Potential reactivity has been identified in most of the rock types used as aggregates around the world. The most common reactive rocks are sedimentary (e.g. opaline sandstone) and metamorphic (e.g. gneiss). However, igneous rocks such as granites have also proved to be reactive in some areas and innocuous in many other regions. It has been concluded that the designation is not enough to label a rock as reactive and that microstructure is very often the determinant factor of reactivity. In the present study a summary ismade on the state-of-the-art on alkali– aggregate reactions. Emphasis is given on the identification of potentially reactive aggregates based on petrographic methods. Examples from a large number of samples analysed in the scope of a research project are presented.

Apresentam-se algumas imagens associadas à, atualmente, bem importante redescoberta da matéria da Imagem urbana, neste caso a "preto e branco" à temática da "Lisboa mais nova", e neste caso ao exemplar Bairro de Olivais-Norte, realizado nos anos 60 do século passado, e que se integra no Bairro da Encarnação.

Apresentam-se algumas imagens associadas à, atualmente, bem importante redescoberta da matéria da Imagem urbana, neste caso, numa perspetiva de associação entre imagens urbanas e naturais/paisagísticas, proporcionadas pelos excelentes exemplos urbanos e residenciais evidentes no modelar bairro modernista dos Olivais-Norte/Encarnação, em Lisboa.

Apresentam-se algumas imagens associadas à, atualmente, bem importante redescoberta da matéria da Imagem urbana, neste caso com algumas vistas da Lisboa mais velha e de uma última vista de Braga.

Apresentam-se algumas imagens associadas à, atualmente, bem importante redescoberta da matéria da Imagem urbana, neste caso a "preto e branco" (e cinzentos) e especificamente à temática da "Lisboa mais antiga", a dos velhos bairros.

For farmers, management of cattle slurry (CS) is now a priority, in order to improve the fertilizer value of the slurry and simultaneously minimize its environmental impact. Several slurry pre-treatments and soil application methods to minimize ammonia emissions are now available to farmers, but the impact of such management strategies on groundwater is still unclear. A laboratory experiment was performed over 24 days in controlled conditions, with undisturbed soil columns (sandy soil) in PVC pipes (30 cm high and 5.7 cm in diameter). The treatments considered (4 replicates) were: a control with no amendment (CTR), injection of whole CS (WSI), and surface application of: whole CS (WSS), acidi