Artigos de Revista

O presente artigo, alicerçado nos Projetos de investigação CyberParks e C3Places, examina como as tecnologias digitais podem envolver os utilizadores na cocriação de um espaço público aberto que responda às suas necessidades, explorando o papel mediador das Tecnologias da Informação e da Comunicação (TIC) nesse processo. Partindo de resultados preliminares dos dois projetos, será explorado mais especificamente o uso do espaço público por adolescentes e discutida a necessidade de repensar o espaço público através de uma perspetiva mais participada.

Depois de uma pequena introdução sobre a relação entre os equipamentos e e as instalações domésticas e a qualidade arquitectónica, desenvolve-se uma reflexão geral sobre equipamentos e instalações domésticas, abordam-se alguns aspectos considerados relativamente “inovadores” e/ou muito específicos e conclui-se com um conjunto de aspetos muito circunscritos às instalações domésticas.

In many water distribution systems, water losses are a major problem and an integrated management strategy is required for both the efficient use of water resources and the minimisation of non-revenue water. For foul sewer systems, the inflow of stormwater and infiltration of groundwater affects the management of both sewer systems and wastewater treatment plants. Monitoring of flows represents a critical task within approaches for control of either water losses in distribution systems and infiltration and rain-induced inflows in foul systems. Implementation of monitoring typically involves the following steps: (i) system information updating and digital mapping; (ii) system zoning; and (iii) system flow monitoring. Costs for monitoring are essential for utilities to estimate more accurately the costs of control of water losses, infiltration and inflow and to support more robust decision-making. Costs and infrastructure data were collected from 20 Portuguese water and wastewater utilities. Multiple linear regression analysis is used to obtain cost functions for meter chambers as a function of the volume and for purchase and installation of flow meters as a function of nominal diameter in water supply systems. For the steps of system information updating, digital mapping and system zoning single unit costs are estimated.

The construction sector has a key role to play in achieving the global objectives of sustainable development. At the request of society and consumers, there is a growing incentive to use sustainable and environmentally friendly construction materials, also with lower energy incorporated. Biocomposites, containing biopolymers and/or natural fibres, have less built-in energy than conventional materials traditionally used by the construction industry. This aspect has originated significant increase in their use in the field of construction. While biocomposite products already perform satisfactorily in many construction applications, they still need to be upgraded in some specific characteristics that are undergoing research and technological development. Sometimes bio-materials are strongly formulated or coupled with nanomaterials, to improve some specific properties of the final product. Like a conventional construction product, these biobased materials and products need to be specified according to building regulations and small-scale assemblies and full-sized test rigs need to be subjected to testing and evaluation to industry and standards targets. Thus, in environmental conditions of application they not should show curvature, swelling, decohesion or other signals of degradation, delamination or fracture, they should have good biologic resistance, good reaction to fire, no flaming or no flame spread, and minimum quantified mechanical properties will be required. In this communication final products for building façades, constituted by bio-composites, as well as Veture panel for thermal insulation consisting of WPC (skin) and an nanoaerogel core (insulation material), are assessed at macro scale. The results are analysed and discussed taking into account the current requirements for the constructive applications in view and its fitness for use is evaluated.

Connecting storm-sewers located at rather different elevations may be made with vortex drop shafts in which the energy dissipation is made by the friction between the vertical shaft and the flow and downstream by the impinging jet in a dissipation chamber. Following the first model design in the 1940s, different types of vortex drop shafts have been developed. One of the most used type is the so-called spiral vortex drop shaft developed to work in supercritical flow with good performance in both energy dissipation and space constrains. In this paper, an experimental flow characterization in a spiral vortex drop shaft is conducted covering the three main components of these structures, namely the inlet channel, the vertical shaft and the dissipation chamber. The results include measurement of water depths, pressure and velocity.

Na sequência de uma breve nota introdutória, que chama atenção para se privilegiar, neste artigo, uma abordagem do “desenho” das guardas, parapeitos e peitoris domésticos associado à matéria da qualidade arquitectónica, desenvolvem-se alguns aspetos de projeto desses elementos ligados, especificamente, às essenciais preocupações de segurança e visibilidades estratégicas e, sequencialmente, às diversificadas e importantes matérias da apropriação.

Nowadays, humanity is consuming unsustainably the planet’s resources. In the scope of energy resource consumption, e.g., the intense use of fossil fuels has contributed to the acceleration of climate changes on the planet, and the overriding need to increase energy efficiency in all sectors is now widely recognized, aiming to reduce greenhouse gases (GHG) emissions by 69% in 2030. Largely due to climate changes,water has also become a critical resource on the planet and hydric stress risk will rise significantly in the coming decades. Accordingly, several countries will have to apply measures to increase water efficiency in all sectors, including at the building level. These measures, in addition to reducing water consumption, will contribute to the increase of energy efficiency and to the decrease of GHG emissions, especially of CO2. Therefore, the nexus water energy in buildings is relevant because the application of water efficiency measures can result in a significant contribution to improve buildings’ energy efficiency and the urban water cycle (namely in abstraction, treatment, and pumping). For Mediterranean climate, there are few studies to assess the extent and impact of this nexus. This study presents the assessment of water-energy nexus performed in a university building located in a mainland Portugal central region. The main goals are to present the results of the water and energy efficiency measures implemented and to assess the consequent reduction of water, above 37%, and energy (30%) consumption, obtained because of the application of water-efficient devices and highly efficient light systems in the building. The water efficiency increase at the building level represents at the urban level an energy saving in the water supply system of 406 kWh/ year, nearly 0.5% of the building energy consumption, with a consequent increase in the energy efficiency and in the reduction of GHG emissions. Complementarily, other energy-efficient measures were implemented to reduce the energy consumption. As the building under study has a small demand of domestic hot water with no hydro pressure pumps and has a small water-energy nexus, it was concluded that the significant reduction of the building energy consumption did not influence the indoor comfort.

Investigou-se a capacidade de sedimentos em suspensão no estuário do Tejo para co-transportar Escherichia coli, como indicador do comportamento das bactérias entéricas. Esta capacidade foi atestada i) pela correlação entre a concentração de sólidos suspensos totais e de E. coli em amostras de água colhidas na praia de Algés, cais de Alcântara e marina do Parque das Nações, à superfície (0,15 m) e próximo do fundo (1 - 9 m), na preia- e baixa-mar, bem como ii) pela co-deposição de E. coli e sedimentos em suspensão nas amostras. O co-transporte de E. coli foi particularmente significativo para os sedimentos com uma estrutura porosa rica em substâncias poliméricas extracelulares (Alcântara e Parque das Nações), cuja tendência para flocular foi evidenciada em ensaios de sedimentação em coluna. Considerando i) os valores dos coeficientes de atenuação da radiação ultravioleta das águas amostradas, ii) a sua dependência da concentração em sólidos suspensos e iii) os teores a que estes ocorrem no estuário, inferiu-se que neste a radiação UV-B extingue-se para valores próximos do nulo a menos de 1,5 m de profundidade e que, portanto, a influência da radiação solar no decaimento da contaminação bacteriana é apenas relevante em zonas pouco profundas do estuário do Tejo e com baixo teor em sólidos suspensos.

In recent years, there has been an increasing interest in the application of machine learning for the prediction of pavement performance. Prediction models are used to predict the future pavement condition, helping to optimally allocate maintenance and rehabilitation funds. However, few studies have proposed a systematic approach to the development of machine learning models for pavement performance prediction. Most of the studies focus on artificial neural networks models that are trained for high accuracy, disregarding other suitable machine learning algorithms and neglecting the importance of models’ generalisation capability for Pavement Engineering applications. This paper proposes a general machine learning approach for the development of pavement performance prediction models in pavement management systems (PMS). The proposed approach supports different machine learning algorithms and emphasizes generalisation performance. A case study for prediction of International Roughness Index (IRI) for 5 and 10-years, using the Long-Term Pavement Performance, is presented. The proposed models were based on a random forest algorithm, using datasets comprising previous IRI measurements, structural, climatic, and traffic data.