802 resultados para smart meters


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Under the European Union Renewable Energy Directive each Member State is mandated to ensure that 10% of transport energy (excluding aviation and marine transport) comes from renewable sources by 2020. The Irish Government intends to achieve this target with a number of policies including ensuring that 10% of all vehicles in the transport fleet are powered by electricity by 2020. This paper investigates the impact of the 10% electric vehicle target in Ireland in 2020 using a dynamic programming based long term generation expansion planning model. The model developed optimizes power dispatch using hourly electricity demand curves up to 2020, while incorporating generator characteristics and certain operational requirements such as energy not served and loss of load probability while satisfying constraints on environmental emissions, fuel availability and generator operational and maintenance costs. Two distinct scenarios are analysed based on a peak and off-peak charging regimes in order to simulate the effects of the electric vehicles charging in 2020. The importance and influence of the charging regimes on the amount of energy used and tailgate emissions displaced is then determined.

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Semiconductor-sensitised photocatalysis is a well-established and growing area of research, innovation and commercialisation; the latter being mostly limited to the use of TiO2 as the semiconductor. Most of the work on semiconductor photocatalytic systems uses oxygen as the electron acceptor and explores a wide range of electron donors; such systems can be considered to be examples of oxidative photocatalysis, OP. OP underpins most current examples of commercial self-cleaning materials, such as: glass, tiles, concrete, paint and fabrics. OP, and its myriad of applications, have been reviewed extensively over the years both in this journal and elsewhere. However, the ability of TiO2, and other semiconductor sensitisers, to promote reductive photocatalysis, RP, especially of dyes, is significant and, although less well-known, is of growing importance. In such systems, the source of the electrons is some easily oxidised species, such as glycerol. One recent, significant example of a RP process is with respect to photocatalyst activity indicator inks. paiis, which provide a measure of the activity of a photocatalytic film under test via the rate of change of colour of the dye in the ink coating due to irreversible RP. In contrast, by incorporating the semiconductor sensitiser in the ink, rather than outside it, it is possible to create an effective UV dosimeter, based on RP, which can be used as a sun-burn warning indicator. In the above examples the dye is reduced irreversibly, but when the photocatalyst in an ink is used to reversibly photoreduce a dye, a novel, colourimetric oxygen-sensitive indicator ink can be created, which has commercial potential in the food packaging industry. Finally, if no dye is present in the ink, and the semiconductor photocatalyst-loaded ink film coats an easily reduced substrate, such as a metal oxide film, then it can be used to reduce the latter and so, for example, clean up tarnished steel. The above are examples of smart inks, i.e. inks that are active and provide either dynamic information (such as UV dose or O2 level) or a useful function (such as tarnish removal), and all work via a RP process and are reviewed here

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The use of an acid violet 7 (AV7) smart ink to assess the activity of photocatalytic paint is demonstrated. A linear correlation is established between the change in oxidized dye concentration, as measured by diffuse reflectance, and the change in the green component of the RGB color values, obtained using a portable hand-held scanner, suggesting that such tests can be monitored easily using an inexpensive piece of hand-held office equipment, as opposed to an expensive lab-based instrument, such as a diffuse reflectance UV/vis spectrophotometer. The bleaching of the AV7 follows first order kinetics, at a rate that is linearly dependent upon the UVA irradiance (0.30–3.26 mW cm–2). A comparison of relative rate of bleaching of the AV7 ink with the relative rate of removal of NOx, as determined using the ISO test (ISO 22197-1:2007), established a linear relationship between the two sets of results and the relevance of this correlation is discussed briefly.

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The azo dye, basic blue 66 (BB66) is used in a photocatalyst activity indicator ink (paii) to assess the activity of low activity photocatalytic surfaces, such as commercial photocatalytic tiles and silicone contaminated self-cleaning glass. The BB66 paii is shown to respond much faster than a previously reported, resazurin (Rz) based paii, i.e. the use of a BB66 paii on low activity self-cleaning tiles was found to be >6 times faster than the Rz paii. The BB66 paii is also shown to be effective at assessing the activity of piece of commercial self-cleaning glass contaminated with a coating of silicone, on which the Rz ink, in contrast, failed to show any significant change in colour over the same time period.

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Novel, reversible (reusable) photocatalyst activity indicator labels, which undergo a rapid colour change when in contact with a photocatalytic film via the photoreduction of methylene blue contained within the label’s adhesive, are explored as a method for assessing the activity of self-cleaning glass in situ and the laboratory, using digital photography.

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This paper presents a framework for a telecommunications interface which allows data from sensors embedded in Smart Grid applications to reliably archive data in an appropriate time-series database. The challenge in doing so is two-fold, firstly the various formats in which sensor data is represented, secondly the problems of telecoms reliability. A prototype of the authors' framework is detailed which showcases the main features of the framework in a case study featuring Phasor Measurement Units (PMU) as the application. Useful analysis of PMU data is achieved whenever data from multiple locations can be compared on a common time axis. The prototype developed highlights its reliability, extensibility and adoptability; features which are largely deferred from industry standards for data representation to proprietary database solutions. The open source framework presented provides link reliability for any type of Smart Grid sensor and is interoperable with existing proprietary database systems, and open database systems. The features of the authors' framework allow for researchers and developers to focus on the core of their real-time or historical analysis applications, rather than having to spend time interfacing with complex protocols.

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As modern power grids move towards becoming a smart grid, there is an increasing reliance on the data that is transmitted and processed by ICT systems. This reliance introduces new digital attack vectors. Many of the proposed approaches that aim to address this problem largely focus on applying well-known ICT security solutions. However, what is needed are approaches that meet the complex concerns of the smart grid as a cyber-physical system. Furthermore, to support the automatic control loops that exist in a power grid, similarly automatic security and resilience mechanisms are needed that rely on minimal operator intervention. The research proposed in this paper aims to develop a framework that ensures resilient smart grid operation in light of successful cyber-attacks.

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This paper presents a new methodology for characterising the energy performance of buildings suitable for city-scale, top-down energy modelling. Building properties that have the greatest impact on simulated energy performance were identified via a review of sensitivity analysis studies. The methodology greatly simplifies the description of a building to decrease labour and simulation processing overheads. The methodology will be used in the EU FP7 INDICATE project which aims to create a master-planning tool that uses dynamic simulation to facilitate the design of sustainable, energy efficient smart cities.

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With the development and deployment of IEC 61850 based smart substations, cybersecurity vulnerabilities of supervisory control and data acquisition (SCADA) systems are increasingly emerging. In response to the emergence of cybersecurity vulnerabilities in smart substations, a test-bed is indispensable to enable cybersecurity experimentation. In this paper, a comprehensive and realistic cyber-physical test-bed has been built to investigate potential cybersecurity vulnerabilities and the impact of cyber-attacks on IEC 61850 based smart substations. This test-bed is close to a real production type environment, and has the ability to carry out end-to-end testing of cyber-attacks and physical consequences. A fuzz testing approach is proposed for detecting IEC 61850 based intelligent electronic devices (IEDs) and validated in the proposed test-bed.

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Application of sensor-based technology within activity monitoring systems is becoming a popular technique within the smart environment paradigm. Nevertheless, the use of such an approach generates complex constructs of data, which subsequently requires the use of intricate activity recognition techniques to automatically infer the underlying activity. This paper explores a cluster-based ensemble method as a new solution for the purposes of activity recognition within smart environments. With this approach activities are modelled as collections of clusters built on different subsets of features. A classification process is performed by assigning a new instance to its closest cluster from each collection. Two different sensor data representations have been investigated, namely numeric and binary. Following the evaluation of the proposed methodology it has been demonstrated that the cluster-based ensemble method can be successfully applied as a viable option for activity recognition. Results following exposure to data collected from a range of activities indicated that the ensemble method had the ability to perform with accuracies of 94.2% and 97.5% for numeric and binary data, respectively. These results outperformed a range of single classifiers considered as benchmarks.

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A engenharia de tecidos é um domínio tecnológico emergente em rápido desenvolvimento que se destina a produzir substitutos viáveis para a restauração, manutenção ou melhoria da função dos tecidos ou órgãos humanos. Uma das estratégias mais predominantes em engenharia de tecidos envolve crescimento celular sobre matrizes de suporte (scaffolds), biocompatíveis e biodegradáveis. Estas matrizes devem possuir não só elevadas propriedades mecânicas e vasculares, mas também uma elevada porosidade. Devido à incompatibilidade destes dois parâmetros, é necessário desenvolver estratégias de simulação de forma a obter estruturas optimizadas. A previsão real das propriedades mecânicas, vasculares e topológicas das matrizes de suporte, produzidas por técnicas de biofabricação, é muito importante para as diversas aplicações em engenharia de tecidos. A presente dissertação apresenta o estado da arte da engenharia de tecidos, bem como as técnicas de biofabricação envolvidas na produção de matrizes de suporte. Para o design optimizado de matrizes de suporte foi adoptada uma metodologia de design baseada tanto em métodos de elementos finitos para o cálculo do comportamento mecânico, vascular e as optimizações topológicas, como em métodos analíticos para a validação das simulações estruturais utilizando dados experimentais. Considerando que as matrizes de suporte são estruturas elementares do tipo LEGO, dois tipos de famílias foram consideradas, superfícies não periódicas e as superfícies triplas periódicas que descrevem superfícies naturais. Os objectivos principais desta dissertação são: i) avaliar as técnicas existentes de engenharia de tecidos; ii) avaliar as técnicas existentes de biofabricação para a produção de matrizes de suporte; iii) avaliar o desempenho e comportamento das matrizes de suporte; iv) implementar uma metodologia de design de matrizes de suporte em variáveis tais como a porosidade, geometria e comportamento mecânico e vascular por forma a auxiliar o processo de design; e por fim, v) validar experimentalmente a metodologia adoptada.

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This work reports one possible way to develop new functional coatings used to increase the life time of metallic structures. The functionalities selected and attributed to model coatings in the frame of this work were corrosion protection, self-sensing and prevention of fouling (antifouling). The way used to confer those functionalities to coatings was based on the encapsulation of active compounds (corrosion inhibitors, pH indicators and biocides) in micro and nanocontainers followed by their incorporation into the coating matrices. To confer active corrosion protection, one corrosion inhibitor (2-mercaptobenzothiazole, MBT) was encapsulated in two different containers, firstly in silica nanocapsules (SiNC) and in polyurea microcapsules (PU-MC). The incorporation of both containers in different models coatings shows a significant improvement in the corrosion protection of aluminum alloy 2024 (AA2024). Following the same approach, SiNC and PU-MC were also used for the encapsulation of phenolphthalein (one well known pH indicator) to introduce sensing properties in polymeric coatings. SiNC and PU-MC containing phenolphthalein acted as corrosion sensor, showing a pink coloration due to the beginning of cathodic reaction, resulting in a pH increase identified by those capsules. Their sensing performance was proved in suspension and when integrated in coatings for aluminium alloy 2024 and magnesium alloy AZ31. In a similar way, the biocide activity (antifouling) was assigned to two polymeric matrices using SiNC for encapsulation of one biocide (Dichloro-2-octyl-2H-isothiazol-3-one, DCOIT) and also SiNC-MBT was tested as biocide. The antifouling activity of those two encapsulated compounds was assessed through inhibition and consequent decrease in the bioluminescence of modified E. coli. That effect was verified in suspension and when incorporated in coatings for AISI 1008 carbon steel. The developed micro and nanocontainers presented the desired performance, allowing the introduction of new functionalities to model coatings, showing potential to be used as functional additives in the next generation of multifunctional coatings.