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Emissions characterization from EURO 5 diesel/biodiesel passenger car operating under the new European driving cycle
Publication . Lopes, M.; Serrano, L.; Ribeiro, I.; Cascão, P.; Pires, N.; Rafael, S.; Tarelho, L.; Monteiro, A.; Nunes, T.; Evtyugina, M.; Nielsen, O.J.; Gameiro da Silva, M.; Miranda, A.I.; Borrego, C.
The increasing demand of petroleum based fuels and their use in internal combustion engines have adverse effect on air quality and climate change. Production of biofuels promises substantial improvement in air quality through reducing emission from biofuel operated vehicles. In this study the influence of the fuel mixture on EURO 5 vehicle exhaust emissions operating under the New European Driving Cycle (NEDC) and in hot operating conditions was analysed. Distinct diesel/biodiesel ratios (B0 (100%/0%), B7 (93%/7%) and B20 (80%/20%), volume basis) were considered. Experiments were conducted on a chassis dynamometer examining several pollutants, namely: carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NO and NO2), particulate matter (PM10 and PM2.5) and total volatile organic compounds (VOC). Moreover, a VOC speciation analysis by gas chromatography was performed to explore the emission variations regarding a set of seventeen VOC.The biodiesel fuel blends showed significant differences in combustion efficiency. An increasing amount of biodiesel in the fuel results in decreasing trends regarding NO, and particulate matter emissions. However, nitrogen dioxide and total VOC emissions increase with the biofuel content in the fuel. Moreover, the VOC speciation analysis suggests that the set of VOC present in exhausted gases is clearly fuel dependent.
A Mechanism for Verifying the Integrity and Immutability of Tuberculosis Data Using IOTA Distributed Ledger Technology
Publication . Lima, Vinícius; Bernardi, Filipe; Rijo, Rui; Ueyama, Jó; Alves, Domingos
Background: Intensified research and innovation and rapid uptake of new tools, interventions, and strategies are crucial to fight Tuberculosis, the world's deadliest infectious disease. The sharing of health data remains a significant challenge. Data consumers must be able to verify the consistency and integrity of data. Solutions based on distributed ledger technologies may be adequate, where each member in a network holds a unique credential and stores an identical copy of the ledger and contributes to the collective process of validating and certifying digital transactions. Objectives: This work proposes a mechanism and presents a use case in Digital Health to allow the verification of integrity and immutability of TB electronic health records. Methods: IOTA was selected as a supporting tool due to its data immutability, traceability and tamper-proof characteristics. Results: A mechanism to verify the integrity of data through hash functions and the IOTA network is proposed. Then, a set of TB related information systems was integrated with the network. Conclusion: IOTA technology offers performance and flexibility to enable a reliable environment for electronic health records.
Mechanisms of bioinvasions by coastal crabs using integrative approaches – A conceptual review
Publication . Rato, Lénia D.; Crespo, Daniel; Lemos, Marco F. L.
Crustaceans are amongst the most reported invaders of coastal habitats, and predatory brachyuran crabs one of the most successful marine invasive groups. They hold high tolerance to abiotic stress and their genetic, life-history, and behavioural adaptation mechanisms prompt their invasive conspicuousness. However, there is a generalized ambiguity on the specific processes that make these bioinvasions successful. No trait-related patterns have yet been found, mostly since traits attributed solely to non-indigenous crab species lack confirmation by comparison with their native counterparts and across each other. Therefore, this review discusses the available literature on fitness and plasticity of brachyuran crabs under global changes, and advances the increasing importance of addressing native versus non-native invasive species comparisons in the annals of brachyura invasion dynamics. Further on, integrative approaches are highlighted and proposed as innovative tools to disentangle trait-related tolerance, overall crab phenotypic plasticity and further adaptation. These indicator tools will advance the knowledge on crabs’ invasive potential, which ultimately affects upcoming population dynamics and ecosystem services, adding value to an effective management of coastal bioinvasions.
Pervasive Information Systems to Intensive Care Medicine. Technology Acceptance Model
Publication . Aguiar, Jorge; Portela, Filipe; Santos, Manuel Filipe; Machado, José; Abelha, António; Silva, Álvaro; Rua, Fernando; Pinto, Filipe
The usability of information systems in critical environments like Intensive Care Units (ICU) is far than the expected and desirable. Typically, ICUs have a set of not integrated information silos and a high number of data recorded in paper. Whenever ICU professionals need to make a decision they have to deal with a high number of data sources containing useful information. Unfortunately, they can't use those sources due to the difficulty of evaluating them in a correct time. Pervasive Intelligent Decision Support Systems (PIDSS), operating automatically and in real-time, can be used to improve the decision making if they are suited to the requirements of the ICU. In this work a PIDSS have been assessed in terms of quality and user acceptance making use of Technology Acceptance Model (TAM). TAM proved to be very useful when combined with Delphi method features to involve the professionals and to make the system usable.
Cross‐polarisation discrimination studies of single trees at 20 and 62.4 GHz
Publication . Caldeirinha, Rafael F. S.; Al‐Nuaimi, Miqdad O.
This study addresses the characterisation of cross‐polarisation discrimination of re‐radiated signals from natural trees performed in the vicinity around deep signal fades. Results presented in this study will explain the signal behaviour observed in the various regions around the tree. This has been addressed in this study through a combination of analytical and experimental modelling based on thorough examination of the re‐radiation functions of single trees and appropriate measurements performed under controlled environments, at 20 and 62.4 GHz. The identification of three distinct regions of interest in the scatter (re‐radiated) field is discussed in this study, where it is shown that depolarisation, in addition to absorption and scatter, is an important factor formulating accurate models for propagation in vegetation media.