Agrupamento de dados visual interactivo

Com a crescente geração, armazenamento e disseminação da informação nos últimos anos, o anterior problema de falta de informação transformou-se num problema de extracção do conhecimento útil a partir da informação disponível. As representações visuais da informação abstracta têm sido utilizadas para auxiliar a interpretação os dados e para revelar padrões de outra forma escondidos. A visualização de informação procura aumentar a cognição humana aproveitando as capacidades visuais humanas, de forma a tornar perceptível a informação abstracta, fornecendo os meios necessários para que um humano possa absorver quantidades crescentes de informação, com as suas capacidades de percepção. O objectivo das técnicas de agrupamento de dados consiste na divisão de um conjunto de dados em vários grupos, em que dados semelhantes são colocados no mesmo grupo e dados dissemelhantes em grupos diferentes. Mais especificamente, o agrupamento de dados com restrições tem o intuito de incorporar conhecimento a priori no processo de agrupamento de dados, com o objectivo de aumentar a qualidade do agrupamento de dados e, simultaneamente, encontrar soluções apropriadas a tarefas e interesses específicos. Nesta dissertação é estudado a abordagem de Agrupamento de Dados Visual Interactivo que permite ao utilizador, através da interacção com uma representação visual da informação, incorporar o seu conhecimento prévio acerca do domínio de dados, de forma a influenciar o agrupamento resultante para satisfazer os seus objectivos. Esta abordagem combina e estende técnicas de visualização interactiva de informação, desenho de grafos de forças direccionadas e agrupamento de dados com restrições. Com o propósito de avaliar o desempenho de diferentes estratégias de interacção com o utilizador, são efectuados estudos comparativos utilizando conjuntos de dados sintéticos e reais.

Resposta contextual automática a mensagens electrónicas

A evolução tecnológica, associada às mudanças sociais a que temos assistido, nomeadamente nas últimas décadas, originou mudanças significativas na forma como os utentes interagem com as instituições, passando a privilegiar a utilização de meios electrónicos, tais como as mensagens de correio electrónico, em detrimento de formas mais tradicionais, como a carta e o telefone. Neste contexto, sendo o ISEP uma instituição de ensino superior que alberga milhares de alunos e recebe centenas de novos alunos todos os anos, necessita de ter condições para que possa responder de forma atempada às inúmeras mensagens de correio electrónico que recebe. Esta necessidade fez com que surgisse um projecto, de nome SiRAC, que servisse para auxiliar na resposta a essas mensagens. O SiRAC tem como objectivo responder a mensagens de correio electrónico de forma automática. De salientar que se admite não ser possível responder a todas as mensagens, privilegiando-se aquelas que são recorrentemente colocadas à Divisão Académica. Assim será possível encurtar o tempo de comunicação entre os diversos intervenientes, criando uma relação mais próxima entre o ISEP e o público que o contacta. O SiRAC analisa as mensagens e procura responder de forma automática sempre que o seu conteúdo possa ser classificado como fazendo parte de um conjunto de questões previamente identificadas pelos recursos humanos da Divisão Académica como recorrentes e para as quais já exista uma resposta tipo. As questões constantes da mensagem são identificadas através de palavras e expressões normalmente associadas aos diferentes tipos de questão. O envio da resposta pressupõe a identificação correcta dos tipos associados e de acordo com requisitos mínimos definidos, de forma a evitar enviar uma resposta errada a uma mensagem. A implementação do SiRAC permite a libertação de recursos humanos da Divisão Académica que anteriormente estavam afectas à resposta de mensagens para o desempenho de outras funções.

Strabismus, visual acuity, and uncorrected refractive error in Portuguese children aged 6 to 11 years

Introduction: Visual anomalies that affect school-age children represent an important public health problem. Data on the prevalence are lacking in Portugal but is needed for planning vision services. This study was conducted to determine the prevalence of strabismus, decreased visual acuity, and uncorrected refractive error in Portuguese children aged 6 to 11 years. Methods and materials: A cross-sectional study was carried out on a sample of 672 school-age children (7.69 ± 1.19 years). Children received an orthoptic assessment (visual acuity, ocular alignment, and ocular movements) and non-cycloplegic autorefraction. Results: After orthoptic assessment, 13.8% of children were considered abnormal (n = 93). Manifest strabismus was found in 4% of the children. Rates of esotropia (2.1%) were slightly higher than exotropia (1.8%). Strabismus rates were not statistically significant different per sex (p = 0.681) and grade (p = 0.228). Decreased visual acuity at distance was present in 11.3% of children. Visual acuity ≤20/66 (0.5 logMAR) was found in 1.3% of the children. We also found that 10.3% of children had an uncorrected refractive error. Conclusions: Strabismus affects a small proportion of the Portuguese school-age children. Decreased visual acuity and uncorrected refractive error affected a significant proportion of school-age children. New policies need to be developed to address this public health problem.

Boas práticas no rastreio visual infantil

A perda de visão, causada por ambliopia (0.3%‐4%) e seus fatores de risco como estrabismo (2.1%‐4.6%) e erros refrativos não corrigidos (5%‐7.7%), representa um importante problema de saúde pública. O rastreio visual pré‐escolar é, assim, essencial para a deteção de ambliopia e fatores ambliogénicos (refrativos e estrábicos). Os programas de rastreio visual variam na sua aplicação em muitos países em toda a Europa e não se avalia sistematicamente a eficácia dos mesmos. Por esse motivo, é necessária discussão e reflexão sobre a temática: 1. Quais os programas de rastreio mais apropriados para fornecer um correto e atempado tratamento? 2. Será que os programas de rastreio são adequados para reduzir as desigualdades em saúde e o custo para os sistemas de saúde? Objetivo do estudo - Identificar práticas de referência no âmbito do rastreio visual infantil.

Reply to letter to the Editor: Expert opinion on best practice guidelines and competency framework for visual screening in children

The aim of this study was to describe experts’ perception of best-practice guidelines and competency framework for visual screening in children. This study uses qualitative data and shows individual/ group conceptualization. The use of evidence from qualitative studies has traditionally been a fundamental source of knowledge in the clinical and social sciences.

Reading performance in children with visual function anomalies

Aims - To compare reading performance in children with and without visual function anomalies and identify the influence of abnormal visual function and other variables in reading ability. Methods - A cross-sectional study was carried in 110 children of school age (6-11 years) with Abnormal Visual Function (AVF) and 562 children with Normal Visual Function (NVF). An orthoptic assessment (visual acuity, ocular alignment, near point of convergence and accommodation, stereopsis and vergences) and autorefraction was carried out. Oral reading was analyzed (list of 34 words). Number of errors, accuracy (percentage of success) and reading speed (words per minute - wpm) were used as reading indicators. Sociodemographic information from parents (n=670) and teachers (n=34) was obtained. Results - Children with AVF had a higher number of errors (AVF=3.00 errors; NVF=1.00 errors; p<0.001), a lower accuracy (AVF=91.18%; NVF=97.06%; p<0.001) and reading speed (AVF=24.71 wpm; NVF=27.39 wpm; p=0.007). Reading speed in the 3rd school grade was not statistically different between the two groups (AVF=31.41 wpm; NVF=32.54 wpm; p=0.113). Children with uncorrected hyperopia (p=0.003) and astigmatism (p=0.019) had worst reading performance. Children in 2nd, 3rd, or 4th grades presented a lower risk of having reading impairment when compared with the 1st grade. Conclusion - Children with AVF had reading impairment in the first school grade. It seems that reading abilities have a wide variation and this disparity lessens in older children. The slow reading characteristics of the children with AVF are similar to dyslexic children, which suggest the need for an eye evaluation before classifying the children as dyslexic.

Social contextual factors contributing to child and adolescent labor: an ecological analysis

OBJECTIVE: To examine the relationship between social contextual factors and child and adolescent labor. METHODS: Population-based cohort study carried out with 2,512 families living in 23 subareas of a large urban city in Brazil from 2000 to 2002. A random one-stage cluster sampling was used to select families. Data were obtained through individual household interviews using questionnaires. The annual cumulative incidence of child and adolescent labor was estimated for each district. New child and adolescent labor cases were those who had their first job over the two-year follow-up. The annual cumulative incidence of child and adolescent labor was the response variable and predictors were contextual factors such as lack of social support, social deprivation, unstructured family, perceived violence, poor school quality, poor environment conditions, and poor public services. Pearson's correlation and multiple linear regression were used to assess the associations. RESULTS: There were selected 943 families corresponding to 1,326 non-working children and adolescents aged 8 to 17 years. Lack of social support, social deprivation, perceived violence were all positively and individually associated with the annual cumulative incidence of child and adolescent labor. In the multiple linear regression model, however, only lack of social support and perceived violence in the neighborhood were positively associated to child and adolescent labor. No effect was found for poor school quality, poor environment conditions, poor public services or unstructured family. CONCLUSIONS: Poverty reduction programs can reduce the contextual factors associated with child and adolescent labor. Violence reduction programs and strengthening social support at the community level may contribute to reduce CAL.

Longe da vista, longe do coração: o design como “âncora” visual e elemento agregador da atividade museológica

To become an open to outer space, the "museum" acquired new forms and new expressions. The complexity of museological activity thus leads to new representations that alter the initial image of the museum as a building with objects. Their 'boundaries' are now less sharp, not only in relation to the spatial relationship, but also to its temporal dimension, creating an additional challenge which is the recognition of the museum itself. The design, while transdisciplinary activity, thereby assumes a key role in the communication of the museums in its visual representation and recognition of their action. The present study results from a survey conducted in 2010 to 364 Portuguese museums (from a universe of 849 museums), presenting an analysis to its base elements of visual expression of identity (name, logo, symbol, and color).

Distribution system operation supported by contextual energy resource management based on intelligent SCADA

Future distribution systems will have to deal with an intensive penetration of distributed energy resources ensuring reliable and secure operation according to the smart grid paradigm. SCADA (Supervisory Control and Data Acquisition) is an essential infrastructure for this evolution. This paper proposes a new conceptual design of an intelligent SCADA with a decentralized, flexible, and intelligent approach, adaptive to the context (context awareness). This SCADA model is used to support the energy resource management undertaken by a distribution network operator (DNO). Resource management considers all the involved costs, power flows, and electricity prices, allowing the use of network reconfiguration and load curtailment. Locational Marginal Prices (LMP) are evaluated and used in specific situations to apply Demand Response (DR) programs on a global or a local basis. The paper includes a case study using a 114 bus distribution network and load demand based on real data.

Avaliação por fMRI do córtex visual, motor e auditivo através de estimulação sensoriomotora e sonora em desportistas invisuais e desportistas sem deficiência visual

Mestrado em Radiações Aplicadas às Tecnologias da Saúde - Ramo de especialização: Imagem por Ressonância Magnética

Effects of emotional valence and three-dimensionality of visual stimuli on brain activation: an fMRI study

BACKGROUND: Examining changes in brain activation linked with emotion-inducing stimuli is essential to the study of emotions. Due to the ecological potential of techniques such as virtual reality (VR), inspection of whether brain activation in response to emotional stimuli can be modulated by the three-dimensional (3D) properties of the images is important. OBJECTIVE: The current study sought to test whether the activation of brain areas involved in the emotional processing of scenarios of different valences can be modulated by 3D. Therefore, the focus was made on the interaction effect between emotion-inducing stimuli of different emotional valences (pleasant, unpleasant and neutral valences) and visualization types (2D, 3D). However, main effects were also analyzed.METHODS: The effect of emotional valence and visualization types and their interaction were analyzed through a 3x2 repeated measures ANOVA. Post-hoc t-tests were performed under a ROI-analysis approach. RESULTS: The results show increased brain activation for the 3D affective-inducing stimuli in comparison with the same stimuli in 2D scenarios, mostly in cortical and subcortical regions that are related to emotional processing, in addition to visual processing regions. CONCLUSIONS: This study has the potential of clarify brain mechanisms involved in the processing of emotional stimuli (scenarios’ valence) and their interaction with three-dimensionality.

Taxonomy of fundamental concepts of localization in cyber-physical and sensor networks

Localization is a fundamental task in Cyber-Physical Systems (CPS), where data is tightly coupled with the environment and the location where it is generated. The research literature on localization has reached a critical mass, and several surveys have also emerged. This review paper contributes on the state-of-the-art with the proposal of a new and holistic taxonomy of the fundamental concepts of localization in CPS, based on a comprehensive analysis of previous research works and surveys. The main objective is to pave the way towards a deep understanding of the main localization techniques, and unify their descriptions. Furthermore, this review paper provides a complete overview on the most relevant localization and geolocation techniques. Also, we present the most important metrics for measuring the accuracy of localization approaches, which is meant to be the gap between the real location and its estimate. Finally, we present open issues and research challenges pertaining to localization. We believe that this review paper will represent an important and complete reference of localization techniques in CPS for researchers and practitioners and will provide them with an added value as compared to previous surveys.

Modelo do pensamento visual-espacial: transformações geométricas no início da escolaridade

Tese de doutoramento em Ciênicas da Educação: especialidade de Teoria Curricular e Ensino das Ciências

A educação visual do ensino básico: os professores em início de carreira e a orientação dada ao programa

Dissertação de mestrado em Ciências da Educação: área de Educação e Desenvolvimento

Entity localization and tracking: a sensor fusion-based mechanism in WSNs

Knowing exactly where a mobile entity is and monitoring its trajectory in real-time has recently attracted a lot of interests from both academia and industrial communities, due to the large number of applications it enables, nevertheless, it is nowadays one of the most challenging problems from scientific and technological standpoints. In this work we propose a tracking system based on the fusion of position estimations provided by different sources, that are combined together to get a final estimation that aims at providing improved accuracy with respect to those generated by each system individually. In particular, exploiting the availability of a Wireless Sensor Network as an infrastructure, a mobile entity equipped with an inertial system first gets the position estimation using both a Kalman Filter and a fully distributed positioning algorithm (the Enhanced Steepest Descent, we recently proposed), then combines the results using the Simple Convex Combination algorithm. Simulation results clearly show good performance in terms of the final accuracy achieved. Finally, the proposed technique is validated against real data taken from an inertial sensor provided by THALES ITALIA.