Processamento digital de sinal em sistemas de deteção coerente

Mestrado em Engenharia Electrónica e TelecomunicaçõesNas últimas décadas, as comunicações óticas têm estado diretamente ligadas à rápida evolução dos sistemas de comunicações e caso não existissem, hoje seria difícil responder à procura incessante por largura de banda. Contudo, a sua capacidade é limitada, devido a limitações e constrangimentos associados aos equipamentos físicos e, caso não se progrida, não será possível responder adequadamente às futuras necessidades das redes de telecomunicações. Nesse sentido, é conveniente continuar a inovação para novas soluções que permitam superar estas limitações. Nesta dissertação será apresentado um estudo sobre formatos de modulação avançados e multiplexagem da informação, capazes de superar em larga escala as larguras de banda oferecidas atualmente, bem como superar o alcance físico das atuais redes, com custos mais reduzidos. Em particular será analisado o desempenho da deteção coerente como solução para as futuras redes de acesso (NGPON), onde o processamento digital de sinal possui uma importância relevante na eficiência e custo do sistema. Nesse sentido, em simulação será discutido o sistema PDM-QPSK, que se trata de uma promissora técnica de modulação para as futuras redes NGPON, e em laboratório o sistema QPSK a 1.244 Gbps.In the last decades, optical communications introduced a different concept in communications systems. If they do not exist, today would be difficult to answer the demand for bandwidth. This higher bandwidth is related to its physical characteristics, which make them overcome other media. However, its capacity is limited due to the performance of physical equipment and if we do not make progress, it will be not possible to respond to the demands for the future telecommunications networks. Thus, it is appropriate to continue innovation for new solutions to overcome these limitations. In this dissertation, a study will be presented to advanced modulation formats and multiplexing of information, able to overcome in large scale the bandwidth currently offered, as well as overcome the physical reach of existing networks with lower costs. In particular will be analyzed the performance of coherent detection as a solution to the future access networks (NGPON), where the digital signal processing has a significant impact on the efficiency and cost of the system. In this sense, in simulation will be discussed the PDM-QPSK system, that it is a promising modulation technique for future networks, and in the laboratory the QPSK system at 1.244 Gbps

Monitorização e gestão em turismo : uma proposta de dashboard visual

Mestrado em Comunicação MultimédiaA presente investigação propõe-se a atuar no sector turístico, uma vez que este é bombardeado diariamente por uma quantidade considerável de dados e informações. Atualmente, usufrui-se significativamente mais da tecnologia com a finalidade de promover e vender os produtos/serviços disponíveis no mercado. A par da evolução tecnológica, os utilizadores/clientes conseguem comprar, cada vez mais, à distancia de um clique os produtos turísticos que desejam. No entanto, há um variado leque de aplicações sobre o turismo que permitem entender os gostos e as necessidades dos turistas assim como a sua atitude para com o mesmo. Porém, nem as entidades nem os gestores turísticos usufruem inteligentemente dos dados que lhes são facultados. Estes tendem normalmente a prender-se pelo turismo em Portugal e de que forma é que a sua entidade é apresentada acabando por esquecer que os dados podem e devem ser utilizados para expandir o mercado assim como entender/conhecer potenciais mercados. Deste modo, o fundamento principal desta investigação remete para a criação de uma plataforma infocomunicacional que analise na totalidade os dados obtidos, assim como fornecer as ferramentas pertinentes para que se consiga fazer esta análise, nomeadamente através de uma representação infográfica adequada e estratégias de a comunicar aos stakeholders.. Para tal foi aplicada no âmbito desta dissertação a metodologia investigação/ação, vista como um processo cíclico que para além de incluir simultaneamente estas duas vertentes, vai alternando entre a ação e a reflexão critica sendo sustentada por bases teóricas. A criação do protótipo da plataforma Smart Tourism, resultou num sistema inovador que tenta responder aos indicadores escolhidos no Dashbord e ao problema infocomunicacional, tentando criar as bases necessárias para que as entidades consigam analisar de forma mais integrada/sistematizada e racional a atividade turística. Foi por isso, desenvolvido e avaliado qualitativamente um protótipo de base infocomunicacional visual (dashboard visual) que para além do que para além do que já foi referido, consegue proporcionar a gestão dos produtos, clientes, staff e parceiros, aumentando assim o valor deste sector.The present investigation is proposed to operate in the touristic sector, since this one is daily bombarded by a considerable amount of data and information. Nowadays, the use of technology is more significant with the purpose to promote and sell the products/services available in the market. Along with technological evolution, the users/buyers can buy, more and more, with just one click, the touristic products they desire. However, there’s a wide range of applications about tourism which allow to understand the tastes and needs of the tourists, as well as their attitude toward it. Yet, neither entities nor touristic managers enjoy cleverly the data that was been given to them. These usually tend to hold themselves by the tourism in Portugal and in what way their entity is presented, eventually forgetting that data can and should be used to expand the market as well as it helps to understand/know potential markets. Thus, the main foundation of this investigation refers to the creation of an info-communicational platform which analyses, completely, the obtained data as well as provide relevant tools that can do this analysis, namely through an adequate infographic representation and strategies to communicate to stakeholders. For this purpose, it was applied in the context of this dissertation the methodology “investigation/action”, seen as a cyclic process in addition to, simultaneously, include these two strands which goes alternating between action and critical reflection being sustained by theoretical basis. The creation of the prototype of Smart Tourism platform resulted in a modern system that tries to answer to the chosen indicators in the Dashboard and to the infocommunicational problem, trying to create necessary bases so that entities can analyze in a way that is more intregated/systematized and rationally the tourism sector. In this way, it was developed and evaluated qualitatively a base visual infocommunicational prototype (visual dashboard) that beyond what was already mentioned, can provide management of products, customers, staff and partners, raising the value of this sector

Efficiency of different solvents in the extraction of bioactive compounds from Plinia cauliflora and Syzygium cumini fruits as evaluated by paper spray mass spectrometry

Jabuticaba (Plinia cauliflora) and jambolan (Syzygium cumini) fruits are rich in phenolic compounds with antioxidant properties, mostly concentrated in the peel, pulp, and seeds. Among the techniques for identifying these constituents, paper spray mass spectrometry (PS-MS) stands out as a method of ambient ionization of samples for the direct analysis of raw materials. This study aimed to determine the chemical profiles of the peel, pulp, and seeds of jabuticaba and jambolan fruits, as well as to assess the efficiency of using different solvents (water and methanol) in obtaining metabolite fingerprints of different parts of the fruits. Overall, 63 compounds were tentatively identified in the aqueous and methanolic extracts of jabuticaba and jambolan, 28 being in the positive ionization mode and 35 in the negative ionization mode. Flavonoids (40%), followed by benzoic acid derivatives (13%), fatty acids (13%), carotenoids (6%), phenylpropanoids (6%), and tannins (5%) were the groups of substances found in greater numbers, producing different fingerprints according to the parts of the fruit and the different extracting solvents used. Therefore, compounds present in jabuticaba and jambolan reinforce the nutritional and bioactive potential attributed to these fruits, due to the potentially positive effects performed by these metabolites in human health and nutrition.info:eu-repo/semantics/publishedVersio

a study from ecological theory and social network analysis perspective

The objective of the present study was to analyze and compare the setter's decision-making (DM) in the offensive construction of the side-out (attack from the reception) in high-level men's volleyball. The sample consisted of the analysis of 132 games of the Brazilian men's volleyball Super-League 2021/2022, with 22 games for each team. The results showed that the eigenvector values were higher for setting to position 3, central attacker next to the setter, simple block, and obtaining the attack point. In addition, the setter's DM was similar between teams, suggesting that the game strategies aim to provide subsidies for the setter to make the decisions according to the game context in a flexible way and generate benefits for the attackers about the number of blockers, being that under ideal conditions and due to the lifter's correct choices in distribution, central blockers avoid anticipating the setting, and this fact allows the conditions of a single block or double-broken blocks in most cases. As a practical application, setting for the central attacker in position 3 becomes an interesting option for point acquisition and is capable of influencing the number of blockers, as well as the optimal blocking condition. Another application would be for the central attacker to position themselves close to the setter, a strategy that would enable the use of the "pipe" attack in other areas of the court with lower defensive blocking power.9E1A-F9DD-3EB8 | Filipe Manuel ClementeN/

Morphological and Postural changes in the foot during pregnancy and puerperium : a longitudinal study

The aim of this study is to observe the morphological and postural changes to the foot that take place during pregnancy and the puerperium. Method: In this descriptive, observational, longitudinal study, we analysed 23 pregnant women, with particular attention to morphological and postural aspects of the foot, at three time points during and after pregnancy: in weeks 9-13 of gestation, weeks 32-35 of gestation and weeks 4-6 after delivery. The parameters considered were changes in foot length, the Foot Posture Index (FPI) and the Hernández Corvo Index, which were analysed using a pedigraph and taking into account the Body Mass Index (BMI). The same procedure was conducted in each review. Results: The statistical analyses obtained for each foot did not differ significantly between the three measurement times. A pronator-type footprint was most frequently observed during the third trimester of pregnancy; it was predominantly neutral during the postpartum period. Statistically significant differences between the measurement times were obtained in the right foot for cavus vs. neutral foot type (between the first and third trimesters and also between the first trimester and the puerperium) (in both cases, p < 0.0001). Conclusions: Foot length increases in the third trimester and returns to normal in the puerperium. According to FPI findings, the third trimester of pregnancy is characterised by pronation, while the posture returns to neutrality during the postpartum period. During pregnancy, the plantar arch flattens, and this persists during the puerperium. The incidence of cavus foot increases significantly in the third trimester and in the puerperium

Thrombus aspiration in patients with ST-elevation myocardial infarction: results of a national registry of interventional cardiology

BACKGROUND: We aimed to evaluate the impact of thrombus aspiration (TA) during primary percutaneous coronary intervention (P-PCI) in 'real-world' settings. METHODS: We performed a retrospective study, using data from the National Registry of Interventional Cardiology (RNCI 2006-2012, Portugal) with ST-elevation myocardial infarction (STEMI) patients treated with P-PCI. The primary outcome, in-hospital mortality, was analysed through adjusted odds ratio (aOR) and 95% confidence intervals (95%CI). RESULTS: We assessed data for 9458 STEMI patients that undergone P-PCI (35% treated with TA). The risk of in-hospital mortality with TA (aOR 0.93, 95%CI:0.54-1.60) was not significantly decreased. After matching patients through the propensity score, TA reduced significantly the risk of in-hospital mortality (OR 0.58, 95%CI:0.35-0.98; 3500 patients). CONCLUSIONS: The whole cohort data does not support the routine use of TA in P-PCI, but the results of the propensity-score matched cohort suggests that the use of selective TA may improve the short-term risks of STEMI..info:eu-repo/semantics/publishedVersio

Spreading remote lab usage: A system — A community — A Federation

Experiments have been at the heart of scientific development and education for centuries. From the outburst of Information and Communication Technologies, virtual and remote labs have added to hands-on labs a new conception of practical experience, especially in Science, Technology, Engineering and Mathematics education. This paper aims at describing the features of a remote lab named Virtual Instruments System in Reality, embedded in a community of practice and forming the spearhead of a federation of remote labs. More particularly, it discusses the advantages and disadvantages of remote labs over virtual labs as regards to scalability constraints and development and maintenance costs. Finally, it describes an actual implementation in an international community of practice of engineering schools forming the embryo of a first world wide federation of Virtual Instruments System in Reality nodes, under the framework of a project funded by the Erasmus+ Program.info:eu-repo/semantics/publishedVersio