Artigos de Revista

PAC/UF was investigated for removing M. aeruginosa cells and microcystins from natural watersand its performance was compared with the conventional clarifi cation with PAC addition(PAC+C/F/S). Ozonated and clarified waters from Tavira

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Digital preservation aims to keep digital objects accessible over long periods of time, ensuring the authenticity and integrity of these digital objects. In such complex environments, Risk Management is a key factor in assuring the normal behaviour of systems over time. Currently, the digital preservation arena commonly uses Risk Management concepts to assess repositories. In this paper, we intend to go further and propose a perspective where Risk Management can be used not only to assess existing solutions, but also to conceive digital preservation environments. Thus, we propose a Risk Management-based approach to design and assess digital preservation environments, including:·the definition of context and identification of strategic objectives to determine specific requirements and characterize which consequences are acceptable within the identified context;·the identification, analysis and evaluation of threats and vulnerabilities that may affect the normal behaviour of a specific business or the achievement of the goals and conformance to the requirements identified in the context characterization; and,·definition of actions to deal with the risks associated with the identified threats and vulnerabilities.We generalize and survey the main requirements, threats, vulnerabilities and techniques that can be applied in the scope of digital preservation.

This paper illustrates the methodology developed to evaluatethe risk of flooding of a coastal area, as well as theapplication of such methodology to Vale do Lobo beach,situated in the Loulé Municipality, a Portuguese coastal areaunder significant touristic pressure. The methodology isbased on four main steps: a) division of the study area intosub-areas with similar characteristics in terms of coastaldefense; b) determining the probability of exceedance ofpre-set thresholds of flood levels for each study area; c)establishment of qualitative factors related to theconsequences of exceedance of pre-set thresholds of floodlevels; d) combination of the above steps for expeditiousassessment of flood risks.The determination of flood levels follows the methodologypresented in [1] and [2], which is based on the transferenceof the Faro wave-buoy regime to the study area by using theSWAN model integrated in a geographic information system(GIS)

As concerns for the quality and durability of buildings are grow¬ing. solutions are needed to increase the likelihood of being able to preserve the physical and mechanical integrity of constructions. and this is more demanding when the building has historical value (1).Conspicuous among the anomalies currently most observed in buildings' timber structures are those caused by xylotrophic organ¬isms such as rot fungi and subterranean termites. as well as dry¬wood termites and woodworms, The first two occur in timber with high moisture content and the second two in dry timber Keeping timber in a good state of preservation and remediate an infection 01' infestation both normally require the use of chemical compounds [2], Treating the wood or using treated wood not only helps homeowners save money but also conserves forests (3.4], Details of these treatment products should nevertheless be duly noted after applicationUntil the early 1990s the use of CCA (chromated copper arse¬nate) compounds and active substances such as pentachlorophe¬nol. copper, tin or lindane applied in organic solvents (LOSP) was generalized [2-41. Although some of these formulations were very efficient at extending the life of wood. the health hazard to workers and the risk of environmental impact on the soil and landscape has to be seriously considered [3.4]. In the last few decades severerestrictions were therefore imposed on the use of many of the sub¬stances mentioned above in Europe [51. and in the USA where for instance, CCA was phased out of all new residential uses. from Jan¬uary 2004 [61,Some traditional products based on established practices are also in general use, They include linseed oil, a good water repellent finishing, and used motor oil. which is often applied (particularly in Portugal) in the preventive treatment of wood. though with very arguable effectiveness.Present day maintenance or rehabilitation interventions in old buildings will necessarily lead to the use of newer and more envi¬ronmentally benign products on existing timber (Fig. 1). However, the effectiveness of curative/preventive measures is often impaired by the presence of previous treatments or finishes, not always well documented and difficult to characterize.In this context. there is a need for a penetration test that would allow swift evaluation whether a particular new wood preserva¬tive eao be used, The test should also be of minimum disturbance to the structure under rehabilitation,

Flow rate measurement is a common task in many hydraulic infrastructures included in systems with a large impact on the economy. The quality requirements that such measurement must fulfil imply the best knowledge of the measurement results (estimates and measurement uncertainties). Methods such as those given by the Guide for the Expression of Uncertainty in Measurement (GUM) have been widely used as tools to evaluate measurement uncertainties. However, such methods have implicit assumptions on the nature of the mathematical models and the applicability conditions, which are not often taken into account by their users, who apply them regardless of the specific nature of the actual metrological problems. One such assumption is that the output probability function is Gaussian, which is true only if some input conditions are met. In practice, many metrological problems are described by mathematical models with non-ideal conditions, the measurement uncertainty solutions thus being quite different from those predicted by the GUM method. The development of metrological studies has shown that the Monte Carlo method is suitable to deal with non-ideal problems and has several advantages. One such advantage is particularly useful for the specific problem of flow rate measurement using a primary weighing method: the ability to give information on the output quantity probability function. In this way, it is possible not only to obtain the output quantity estimate but also to test the normality of the output measurement uncertainty interval, which in fact has a non-Gaussian shape.

A preferência por Pinho bravo "resinado" / "não resinado" é ainda frequentemente expressa em Cadernos de Encargos. No entanto, as consequências para a qualidade da madeira de Pinheiro bravo (Pinus pinaster Ait.) resultantes da práctica de resinagem à vida (extracção moderada de resina, ao longo de muitos anos) têm sido alvo de discussão, não havendo consenso quanto à vantagem de um ou outro tipo de madeira. Tanto se assiste à preferência por madeira resinada, acreditando que o afluxo de resina aumenta a sua durabilidade, como à preferência por madeira não resinada baseada na sua hipotética maior resistência mecânica. Os conceitos "madeira seca" e "madeira tratada" correspondem a dois parâmetros distintos da especificação de uma madeira e não podem ser confundidos. A secagem da madeira pretende sobretudo minimizar a variação dimensional dos elementos após aplicação em obra, enquanto o tratamento (preservação) da madeira corresponde à introdução na madeira de um produto preservador destinado a conferir-lhe durabilidade adequada face ao risco de ataque de agentes biológicos.

The restoration and maintenance of old renders is one of the key aspects of correct rehabilitation practice. The ideal course of action is to replace the damaged material by a material with compatible characteristics. This work aims to analyze the effect of the maturation process on hardened state characteristics of hydrated powder lime mortars. The rheological characterization shows an air lime mortar thickening behaviour with the length of the test. The different mixes were subjected to a maturation process consisting on keeping them in the fresh state, covered with water, isolated from CO2, during seven days. The specimens and applications were prepared both with the non-matured and the matured mortars. Maturation seems to influence the hardened state characteristics causing a decrease in the capillary values, and an increase on the mechanical strength, which are more evident for mortars with higher binder contents.

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