Language-Based Data Sharing in Web Applications

Cloud development and virtualization of applications is crucially becoming the common practice in the software engineering industry. Many systems and database tools are available to support applications with many instances and views, but all the orchestration of data and functionality in the so-called multi-tenant applications comes with a high development and maintenance cost. Due to the high costs of developing and maintaining such applications, there is an increasing need for languages and tools that support the gradual development of software for a highly shared environment, at the developer and user level. We extend a typed, reactive and incremental programming environment and language with parameterized modules that increase application modularity, with lenses that provide a (filtered) data sharing mechanism between modules, and the (dynamic) verification of module access conditions to implement data privacy. The combination of these mechanisms is a safe and powerful mechanism to design and evolve cloud and web applications. We present a pragmatic programming language supported by a deployed prototype where several examples of applications illustrate this new programming paradigm. We also provide a largerweb application example as a means of showing how the combination of the introduced mechanisms allows for the development of multi-tenant applications, and to compare it against implementations in modern frameworks

Map-based interaction with trajectory data

Tese de doutoramento, Informática (Engenharia Informática), Universidade de Lisboa, Faculdade de Ciências, 2017With the increasing popularity of location based services and mobile tracking technologies, the collection of large amounts of spatio-temporal data became an increasingly common, easier, and more reliable task. In turn, this has emphasized the possibility of analysing georeferenced information, particularly associated with human trajectory data, to identify and understand movement patterns and activities, ultimately, supporting decision making in various contexts. In order to properly analyse and understand the spatio-temporal and the thematic properties associated with these data, adequate visualization techniques are needed. Due to the spatial properties of trajectories, map-based techniques, such as 2D static maps or 3D space-time cubes (STCs) are considered as essential tools for their visualization. However, despite the increasing number of visualization systems, the study regarding their usability, alongside the role of the human user, sometimes with a limited background in data visualization and analysis, are often neglected. In addition to the somewhat disperse, and sometimes even contradictory, results in the literature, these factors, ultimately, emphasize the lack of knowledge to support the choice of particular visualizations, and their design, in different types of tasks. This dissertation addresses these issues through three main sets of contributions, focusing on inexperienced users, in terms of data visualization and analysis: i) the characterization of the dis/advantages of existing map-based techniques (2D static maps and STCs), depending on the types of visual analysis tasks and the focus of the analysis; ii) the improvement of existing visualization techniques, either through the inclusion of additional spatial cues within the STC, or combining both types of techniques in various ways; and iii) the identification of design guidelines for trajectory data visualization, describing various considerations/criteria for the selection of different map-based visualization techniques and their possible interactive features

Visualização da relevância da informação geográfica em aplicações móveis

Tese de mestrado em Engenharia Informática (Sistemas de Informação), apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2011A utilização da informação geográfica a partir de dispositivos móveis é uma área em crescente expansão e, por conseguinte, na última década, tem-se assistido a um crescimento no desenvolvimento de serviços móveis utilizando a informação geográfica, tais como serviços baseados em localização (LBS – Location Based Services) ou serviços de geovisualização móvel. Apesar deste crescimento, existem ainda diversos desafios por investigar na área da visualização de informação em dispositivos móveis. A pequena dimensão do ecrã destes dispositivos conduz a uma necessidade de filtrar e disponibilizar apenas a informação mais relevante para o utilizador. Adicionalmente, essa informação está frequentemente localizada fora da área visível no ecrã, aumentando a carga cognitiva do utilizador na realização de tarefas de pesquisa e tornando complexa a tarefa de navegação. Para a resolução do primeiro problema, têm sido propostos mecanismos para seleccionar a informação relevante baseada em informação sobre o contexto e as preferências do utilizador. Contudo, não é dada qualquer informação sobre a relevância dos objectos de interesse que se encontrem fora da área visível. Relativamente à segunda problemática, têm sido propostas algumas técnicas para a sinalização de objectos fora do ecrã, mas nenhuma delas explora a relevância dos objectos. Este trabalho descreve e avalia a técnica de visualização, denominada HaloDot, que combina a sinalização e identificação de objectos fora da área visível no ecrã (off-screen) com visualização de relevância. Os atributos de relevância baseados na cor e na transparência foram ainda aplicados a outras técnicas de visualização off-screen e comparadas com o HaloDot. Os resultados das avaliações efectuadas sugerem que a utilização da combinação da cor com a transparência é eficiente para a representação da relevância. Adicionalmente, é necessário considerar, pelo menos, três factores na decisão de escolha da técnica de visualização off-screen, nomeadamente: o número de pontos de interesse existentes, a proximidade dos pontos de interesse da área visível no ecrã e a simbologia utilizada para a representação dos pontos de interesse.The use of the geographic information from mobile devices is an area that is becoming increasingly widespread and, therefore, in the last decade, there has been a growth on the development of mobile services using geographical information, like Location Based Services (LBS) or mobile geovisualization services. Despite this growth, there are still several challenges that are worth to investigate on the field of information visualization on mobile devices. The small dimension of these devices‟ screens requires filtering mechanisms to provide only the most relevant information to the user. This information is often located off-screen, increasing the user's cognitive workload to perform search tasks and making the navigational task complex. To solve the first problem several mechanisms have been proposed to select the relevant information, based on information about the context and the user's preferences. However, it does not provide any information about the relevance of points of interest located off-screen. To solve the second problem some techniques have been proposed for the signalization of off-screen objects. None of them, however, explores the relevance of those objects. This work describes and evaluates a visualization technique, called HaloDot, which combines the signalization and identification of off-screen objects with the visualization of their relevance. HaloDot uses color and transparency to express the relevance of off-screen objects. These graphical attributes were also used in other off-screen visualization techniques, which were compared with HaloDot. The results of the performed evaluation suggest that the use of the combination of colour and transparency is efficient for the representation of the relevance. Additionally, it is necessary to take into account three factors to select an off-screen visualization technique, namely: the number of existing points of interest, the proximity of the points of interest to the on-screen area and the simbology used for the representation of the points of interest

Multibody model of the collaborative human-inspired robot charmie

With the worldwide ageing of population, domestic robots can provide important aid by assisting elderly persons with mobility limitations, increasing their autonomy, while reducing caretaker fatigue. Currently, a human-like mobile system, called CHARMIE, is being assembled, which can be applied for those situations. For this purpose, a full multibody model has been developed, which allows for the assessment of the robot’s performance as well as its structural analysis and actuators’ selection. The robot multibody model consists of 40 rigid bodies, interconnected by 34 ideal revolute joints, 10 translational joints, and three rigid joints, resulting in a total of 21 degrees of freedom, namely three for the locomotion, two for the hip, seven for each arm and two for the neck. The system is driven by four linear actuators and 17 motors. The multibody dynamic simulations use an in-house software structured around two approaches: a recursive forward kinematics algorithm based on Euler angles, and a recursive Newton-Euler formulation for solving inverse dynamics. For implementing these approaches, the robot has been modelled as three serial kinematic chains, all starting from its base and finishing in the left end-effector, right end-effector, and head respectively. This work focuses on the model developed for the motion simulation of CHARMIE. The proposed methodology includes seven main steps: (i) identify the main bodies and kinematic chains; (ii) convert the body properties into the required software inputs; (iii) analyze the geometry of the indirectly actuated joints; (iv) model the kinematics of the main bodies with the first recursive algorithm; (v) determine the kinematics of additional bodies; (vi) solve the inverse dynamics of the main bodies with the second recursive algorithm; (vii) manually compute the dynamics of the closed and overconstrained loops. The overall outcomes produced have been validated against those obtained by a commercial software

Q-learning for autonomous mobile robot obstacle avoidance

An approach to the problem of autonomous mobile robot obstacle avoidance using Reinforcement Learning, more precisely Q-Learning, is presented in this paper. Reinforcement Learning in Robotics has been a challenging topic for the past few years. The ability to equip a robot with a powerful enough tool to allow an autonomous discovery of an optimal behavior through trial-and-error interactions with its environment has been a reason for numerous deep research projects. In this paper, two different Q-Learning approaches are presented as well as an extensive hyperparameter study. These algorithms were developed for a simplistically simulated Bot'n Roll ONE A (Fig. 1). The simulated robot communicates with the control script via ROS. The robot must surpass three levels of iterative complexity mazes similar to the ones presented on RoboParty [1] educational event challenge. For both algorithms, an extensive hyperparameter search was taken into account by testing hundreds of simulations with different parameters. Both Q-Learning solutions develop different strategies trying to solve the three labyrinths, enhancing its learning ability as well as discovering different approaches to certain situations, and finishing the task in complex environments

Neuromuscular Jumping Performance and Upper-Body Horizontal Power of Volleyball Players

Gonçalves, CA, Lopes, TJD, Nunes, C, Marinho, DA, and Neiva, HP. Neuromuscular jumping performance and upper-body horizontal power of volleyball players. J Strength Cond Res XX(X): 000-000, 2019-The aim of the current study was to characterize the neuromuscular jumping performance and upper-body horizontal power of elite and subelite volleyball players. In addition, those neuromuscular performances were compared between field positions. One hundred twenty-two male volleyball players participated in the study: 83 elite players (mean ± SD: 24.11 ± 5.57 years) and 39 subelite players (25.38 ± 6.19 years). They were divided according to their playing position: setters (n = 22), opposite hitters (n = 16), middle hitters (n = 30), right-side hitters (n = 38), and liberos (n = 16). Each participant randomly performed 3 repetitions of medicine ball throwing (MBT), countermovement jump (CMJ), CMJ with free arms (CMJFA), and spike jump (SPJ). The results showed no significant differences between positions in the analyzed variables. However, there were differences between elite and subelite in the CMJ (p = 0.000, ηp = 0.12), the CMJFA (p = 0.000, ηp = 0.15), the SPJ (p = 0.000, ηp = 0.21), and MBT (p = 0.001, ηp = 0.09), showing a tendency for increased jumping performance and upper-body horizontal power for elite players. The elite opposite hitters and right-side hitters recorded greater CMJ performances (d = 1.20 and d = 1.62, respectively). The right-side hitters were the only group that showed greater horizontal upper-body muscular power (p = 0.000, d = 1.50). It is suggested that jumping performance is a determining factor for higher-level players, which was more relevant for the opposite hitters and right-side hitters. Nevertheless, the movement pattern of MBT seems to be relevant for the right-side hitters. Coaches should seek to develop jumping ability for the improvement of volleyball performances, without disregarding upper-body performances, depending on the position-specific demands.info:eu-repo/semantics/acceptedVersio

Dynamic modeling of a human-inspired robot based on a Newton-Euler approach

This work deals with the modeling process of a new three dimensional human-like robot for an inverse dynamic analysis. This robot intends to be utilized by caregivers to assist persons with reduced mobility (such as the elderly). The model under analysis is composed by 24 rigid bodies: 3 to represent the robot’s base and locomotion, 4 for the lower limbs and torso, 7 for each arm, and 3 for the head. The resulting multibody system has 19 degrees-of-freedom driven by 4 linear actuators and 15 revolute motors. The proposed approach was implemented using an in-house computational code, and validated against a commercial software for a general spatial motion. The outcomes achieved show that the proposed formulation is computationally effective both in terms of efficiency and accuracy. The general findings of this study are promising and useful for the mechanical design and construction of a real human-like robot prototype

Ergonomic evaluations and of environmental factors in an agroindustrial company of plant products

A busca por maior produtividade devido à crescente demanda por alimentos pode levar a um trabalho árduo, com condições exaustivas e inadequadas. Assim, o objetivo do estudo foi realizar uma avaliação postural em cinco diferentes atividades em uma empresa agroindustrial, bem como mensurar as condições ambientais e organizacionais do local. A análise postural foi realizada por meio de imagens das posturas utilizadas no ambiente de trabalho e das forças requeridas, utilizando o método RULA e o software Ergolandia 6.0, associado a um questionário de avaliação das condições biomecânicas do posto de trabalho, aplicado aos funcionários. Para os fatores ambientais, foram realizadas as análises de ruído (NBR 10152 e NR 17), temperatura (NR 17) e iluminação (NBR ISSO / CIE 8995-1). Entre as cinco atividades analisadas, dois apresentaram necessidade de intervenção postural imediata e modificações no ambiente de trabalho. Além disso, ao analisar as condições biomecânicas do ambiente, apenas duas estações de trabalho apresentaram boas condições. Em relação aos fatores ambientais, apenas um dos postos de trabalho atendia ao padrão de ruído e todos eram inadequados para verificações de temperatura e luminosidade

CHARMIE: a collaborative healthcare and home service and assistant robot for elderly care

The global population is ageing at an unprecedented rate. With changes in life expectancy across the world, three major issues arise: an increasing proportion of senior citizens; cognitive and physical problems progressively affecting the elderly; and a growing number of single-person households. The available data proves the ever-increasing necessity for efficient elderly care solutions such as healthcare service and assistive robots. Additionally, such robotic solutions provide safe healthcare assistance in public health emergencies such as the SARS-CoV-2 virus (COVID-19). CHARMIE is an anthropomorphic collaborative healthcare and domestic assistant robot capable of performing generic service tasks in non-standardised healthcare and domestic environment settings. The combination of its hardware and software solutions demonstrates map building and self-localisation, safe navigation through dynamic obstacle detection and avoidance, different human-robot interaction systems, speech and hearing, pose/gesture estimation and household object manipulation. Moreover, CHARMIE performs end-to-end chores in nursing homes, domestic houses, and healthcare facilities. Some examples of these chores are to help users transport items, fall detection, tidying up rooms, user following, and set up a table. The robot can perform a wide range of chores, either independently or collaboratively. CHARMIE provides a generic robotic solution such that older people can live longer, more independent, and healthier lives.This work has been supported by FCT—Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020. The author T.R. received funding through a doctoral scholarship from the Portuguese Foundation for Science and Technology (Fundação para a Ciência e a Tecnologia) [grant number SFRH/BD/06944/2020], with funds from the Portuguese Ministry of Science, Technology and Higher Education and the European Social Fund through the Programa Operacional do Capital Humano (POCH). The author F.G. received funding through a doctoral scholarship from the Portuguese Foundation for Science and Technology (Fundação para a Ciência e a Tecnologia) [grant number SFRH/BD/145993/2019], with funds from the Portuguese Ministry of Science, Technology and Higher Education and the European Social Fund through the Programa Operacional do Capital Humano (POCH)

As duas principais demonstrações contábeis em Portugal

O trabalho tem como objetivo contribuir para o aumento do conhecimento dos gestores de entidades empresariais acerca de duas demonstrações financeiras obrigatórias em sede do Sistema de Normalização Contabilística (SNC) português: o balanço e a demonstração dos resultados por naturezas. A informação contabilística desempenha um papel crucial para o processo de tomada de decisões económicas, razão pela qual é fulcral que estas demonstrações financeiras sejam elaboradas de maneira a representarem uma imagem verdadeira e apropriada da posição financeira da entidade (o balanço, no caso) e dos resultados das suas operações (a demonstração dos resultados por naturezas, no caso)