Estratégias para uso de redes industriais sem fio do tipo TSCH em aplicações de mobilidade

A utilização de redes sem fio para aplicações industriais surge como uma alternativa para os sistemas cabeados por apresentarem características como flexibilidade de ampliação ou atualização de dispositivos na rede e facilidade de instalação e manutenção. Protocolos de comunicação para redes sem fio industriais, como WirelessHART, foram desenvolvidos para atender a requisitos de operação do setor industrial garantindo entrega de mensagens em tempo real, segurança e confiabilidade. O protocolo WirelessHART foi desenvolvido para atender aplicações de automação de processos, onde as variáveis do processo são alteradas de forma lenta. Quando inseridos elementos de alta dinamicidade, como a presença de dispositivos móveis ou intermitentes, como nos processos de automação fabril, há um impacto negativo no desempenho destas redes devido à rápida mudança de topologia que não é prevista neste protocolo, e que resultam na redução da taxa de sucesso de transmissões. Dentro deste contexto, este trabalho apresenta a análise dos requisitos e a implementação de dispositivos móveis ou intermitentes e gerenciadores de rede em conformidade com a técnica TSCH (Time Synchronized Channel Hopping), como a empregada no WirelessHART. São propostas modificações em procedimentos do protocolo utilizado como base, visando fornecer o suporte a dispositivos móveis que incluem técnicas para agilizar o processo de conexão e desconexão e manter a conectividade do dispositivo enquanto ele se movimenta pela área de cobertura da rede. Os resultados revelam a viabilidade das técnicas propostas, porém, em detrimento de algumas características fundamentais, tais como segurança e baixo consumo de energia. Para mitigar os problemas gerados, são apresentadas propostas a serem implementadas em trabalhos futuros.The use of wireless networks for industrial applications appears as an alternative for wired systems due to its characteristics such as flexibility to add or remove devices on the network and ease of maintenance and installation. Communication protocols for industrial wireless networks, such as WirelessHART, were developed to meet the operating requirements of the industrial sector ensuring real-time communications, security and reliability. The WirelessHART protocol was developed to operate in process automation applications, where process variables are changed slowly. When high dynamics elements are inserted in these networks, such as the presence of mobile or intermittent devices, as seen in factory automation processes, there is a negative impact on the performance of these networks due to the fast topology change that is not supported in this protocol, resulting in the reduction of success rate of transmissions. In this context, this work presents the analysis of requirements and the implementation of mobile or intermittent devices and network managers in accordance with the TSCH (Time Synchronized Channel Hopping) technique, which is used in WirelessHART. Modifications to the procedures of the protocol used as a basis are proposed, aiming to provide support for mobile devices including techniques to reduce time in processes as connection and disconnection and maintain the connectivity of the device while it moves through the network coverage area. The results show the feasibility of the proposed techniques, however, to the detriment of some fundamental characteristics, such as safety and low energy consumption. In order to mitigate the problems generated, proposals are presented to be implemented in future works

Quasi-hereditary covers of Temperley-Lieb algebras and relative dominant dimension

Many connections and dualities in representation theory can be explained using quasi-hereditary covers in the sense of Rouquier. The concepts of relative dominant and codominant dimension with respect to a module, introduced recently by the first-named author, are important tools to evaluate and classify quasi-hereditary covers. In this paper, we prove that the relative dominant dimension of the regular module of a quasi-hereditary algebra with a simple preserving duality with respect to a summand $Q$ of a characteristic tilting module equals twice the relative dominant dimension of a characteristic tilting module with respect to $Q$. To resolve the Temperley-Lieb algebras of infinite global dimension, we apply this result to the class of Schur algebras $S(2, d)$ and $Q=V^{\otimes d}$ the $d$-tensor power of the 2-dimensional module and we completely determine the relative dominant dimension of the Schur algebra $S(2, d)$ with respect to $V^{\otimes d}$. The $q$-analogues of these results are also obtained. As a byproduct, we obtain a Hemmer-Nakano type result connecting the Ringel duals of $q$-Schur algebras and Temperley-Lieb algebras. From the point of view of Temperley-Lieb algebras, we obtain the first complete classification of their connection to their quasi-hereditary covers formed by Ringel duals of $q$-Schur algebras. These results are compatible with the integral setup, and we use them to deduce that the Ringel dual of a $q$-Schur algebra over the ring of Laurent polynomials over the integers together with some projective module is the best quasi-hereditary cover of the integral Temperley-Lieb algebra.Comment: 28 pages, 1 figure. Comments are welcom

Gender diversity on the board and firms’ corporate social responsibility

Corporate Social Responsibility (CSR) has progressively assumed a strategic role in corporate business. In this sense, the board of directors (Board) assumes a preponderant role, since they make decisions about business strategy. One considerably debated characteristic of Board diversity is gender, since women differ from men in terms of personality, communication style, and values. Therefore, this study analyzes the relationship between CSR and gender diversity on Boards, in a sample of European public firms. Results indicate that firms with a higher percentage of women in the Board have higher CSR practices, suggesting that the presence of women can play an important role in terms of CSR decisions, contributing to more social and sustainable firms. Results also suggest that management teams with a higher female percentage associate with better CSR scores, and firms that exhibit both a higher percentage of women on the Board and on the management team improve CSR scores. From an ethical perspective, more socially responsible firms present more trustworthy financial information, and more sustainable economic performance, which decreases risk assessment from their business partners and remaining stakeholders. Thus, results may be of interest to different stakeholders, such as policymakers, investors, and business partners, in order to increase firms’ involvement in CSRinfo:eu-repo/semantics/publishedVersio

Application of machine learning techniques on the discovery and annotation of transposons in genomes

Tese de mestrado integrado. Engenharia Informática e computação. Faculdade de Engenharia. Universidade do Porto. 201

Biomarkers in the Overactive Bladder Syndrome

Environmental managemen

Adversarial Machine Learning Applied to Intrusion and Malware Scenarios: A Systematic Review

Cyber-security is the practice of protecting computing systems and networks from digital attacks, which are a rising concern in the Information Age. With the growing pace at which new attacks are developed, conventional signature based attack detection methods are often not enough, and machine learning poses as a potential solution. Adversarial machine learning is a research area that examines both the generation and detection of adversarial examples, which are inputs specially crafted to deceive classifiers, and has been extensively studied specifically in the area of image recognition, where minor modifications are performed on images that cause a classifier to produce incorrect predictions. However, in other fields, such as intrusion and malware detection, the exploration of such methods is still growing. The aim of this survey is to explore works that apply adversarial machine learning concepts to intrusion and malware detection scenarios. We concluded that a wide variety of attacks were tested and proven effective in malware and intrusion detection, although their practicality was not tested in intrusion scenarios. Adversarial defenses were substantially less explored, although their effectiveness was also proven at resisting adversarial attacks. We also concluded that, contrarily to malware scenarios, the variety of datasets in intrusion scenarios is still very small, with the most used dataset being greatly outdated

Kinematical and neuromuscular assessment of the rowing exercise in the upright position with barbell to improve muscle strength and muscle endurance in group fitness classes

The aim was to assess the interaction between kinematics and neuromuscular responses of subjects performing the rowing exercise with barbell in group fitness classes with different external loads and cadences. Fifteen male subjects performed nine sets of nine repetitions of the selected exercise. Sets were composed by a pair wise combination of different external loads (5, 10 and 20 [kg]) and cadences (1, 2 and 4 musical beats) in a randomized order. Kinematical data was collected with an electrogoniometer and it was assessed the: (i) absolute duration of each exercise repetition; (ii) minimum relative angle between the arm and forearm during the flexion action. Neuromuscular data was collected with superficial electromyography and it was computed the EMG amplitude (aEMG), the EMG room mean square (RMS) and the activation time of five muscles from the arm and trunk. Increasing cadence decreased the absolute duration of the exercise cycle. There was no significant interaction between the joint angle and the external load nor the cadence. Increases in the external load and in the cadence imposed a RMS increase as well. It was also verified a significant interaction among the aEMG and the external load in the four muscle groups