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- Curvas geodésicas : um exemplo com resolução analíticaPublication . Fatelo, J. P.; Martins-Ferreira, N.Apresentamos um exemplo de uma superfície não trivial em R3 na qual as curvas geodésicas são encontradas analiticamente.
- Assistive Mobile Applications for DyslexiaPublication . Madeira, Jorge; Silva, Catarina; Ferreira, Paula Cristina; Marcelino, LuísThe ability to read is one of the main skills of a human being. However, some of us have reading difficulties, regardless of social status, level of intelligence or education. This disorder is the main characteristic of dyslexia and is maintained throughout life,requiring early and specialized intervention. Dyslexia is defined as a learning disturbance in the area of reading, writing and spelling. Although the numbers of prevalence rely heavily on the type of investigation conducted, several studies indicate that up to 17% of the world population is dyslexic, and that men have greater prevalence. In this work we will address the use of assistive mobile applications for dyslexia by analyzing possible solutions and proposing a prototype of a mobile application that can be used by dyslexic and whilst giving feedback both to the dyslexic him/herself and to the assisting technician or teacher. The implemented prototype focuses the Portuguese language and was tested with Portuguese students with ages between 10 and 12 years old. Preliminary results show that the proposed gamified set of activities, allow dyslexics to improve multisensory perception, constituting an added value facilitator of adaptiveness and learning.
- Computer construction of platonic solidsPublication . Gaspar, M.; Leita, M.; Martins-Ferreira, N.; Panda, B. N.In this paper we develop a novel method to generate a 3D geometrical model from 2D planer images. As an example of application, we construct 3D models of each one of the five platonic solids from their platonic graphs.
- Computer tool for maximizing the placement of congruent polyhedraPublication . Gaspar, M.; Alves, N.; Mateus, A.; Martins-Ferreira, N.Given multiple identical polyhedral objects and a parallelepiped container, how should one place the objects so that the largest number fits inside the container? This simple question is important in many applications, yet the answer is elusive. In fact, we know of no published solution for this very general formulation. Still, in many circumstances, further restrictions apply, resulting in a large number of variations requiring different algorithmic strategies. This paper is the continuation of [12] and focus on the fundamental concepts and tools that are used for this kind of problem, such as the no-fit polygon. We also present some of its many variations, giving in particular one that applies to the stereolithographic rapid prototyping technology.
- Modelação do pêndulo caótico : parte 1Publication . Baptista, Diogo Nascimento; Baptista, Alexandra Nascimento; Costelha, HugoUm pêndulo físico, sujeito a um amortecimento e a uma força externa que atua sobre o eixo de rotação deste, reproduz vários tipo de movimentos, que poderão ser periódicos ou não. Controlando a amplitude e a frequência da força externa, o objetivo é prever e caracterizar o tipo de movimentos descritos pelo pêndulo. Neste primeiro trabalho sobre o tema, serão introduzidas as equações necessárias para a modulação do movimento e analizados os dados experimentais resultantes das leituras efetuadas num pêndulo cujo eixo de rotação está sujeito a um movimento horizontal periódico.
- OER, Open Access and Scholarship in Portuguese Higher EducationPublication . Cardoso, Paula; Morgado, Lina; Teixeira, AntónioThe present paper is part of a PhD research, which is being developed in the scope of the Doctoral Programme in Education, specialisation in Distance Education and eLearning at Universidade Aberta, the Portuguese Open University. The theoretical framework for the research is Open Education, particularly the specific fields of Open Educational Resources (OER) and Open Access (OA). The main objective of the research is to identify and understand the awareness, knowledge and attitudes of scholars in Portuguese public Higher Education Institutions (HEI), regarding OER and OA and, in particular, to compare scholars’ awareness, attitudes and perceptions towards OER and OA in the context of their teaching and research practices. This will also allow us to represent the Portuguese reality and, consequently, position the Portuguese public higher education practices within the global panorama and also may be able to inform future decisions, whether institutionally, governmentally or even within a broader perspective. The current paper intends to present the research project and also to reflect the literature review carried out so far, in order to contextualise the research problem and also to describe the methodological procedures defined for the study.
- Sistema de aquisição e registo de sinais biomédicos baseado numa plataforma de desenvolvimento open-source de baixo custoPublication . Jardan, Daniel; Gil, João; Martins, Fernando; Ferreira, Lino; Fonseca-Pinto, RuiEste artigo apresenta um sistema de aquisição e registo de sinais biomédicos baseado na plataforma desenvolvimento open-source Arduino. O sistema tem associado um cartão de memória para registo de dados, bem como um acelerómetro que indica a atividade/postura do paciente. É utilizado um módulo de comunicação Blue- tooth para ligação a um dispositivo móvel (smartphone e tablet) de forma a permitir a parametrização, o comando do sistema de aquisição e a monitorização em tempo real dos dados adquiridos. Estes dados foram usados para calcular o balanço vago-simpático associado a tarefas específicas do dia-a-dia.
- Deconvolution of X-ray Diffraction Profiles Using Genetic Algorithms and Differential EvolutionPublication . Santos, Sidolina P.; Gomez-Pulido, Juan A.; Sanchez-Bajo, FlorentinoSome optimization problems arise when X-ray diffraction profiles are used to determine the microcrystalline characteristics of materials, like the detection of diffraction peaks and the deconvolution process necessary to obtain the pure diffraction profile. After applying the genetic algorithms to solve satisfactorily the first problem, in this work we propose two evolutionary algorithms to solve the deconvolution problem. This optimization problem targets the objective of obtaining the profile that contains the microstructural characteristics of a material from the experimental data and instrumental effects. This is a complex problem, ill-conditioned, since not only there are many possible solutions, but also some of them lack physical sense. In order to avoid such circumstance, the regularization techniques are used, where the optimization of some of their parameters by means of intelligent computing permits to obtain the optimal solutions of the problem.
- Diffusion and distribution of touristic routes: Web platform's architecture on tourism contextPublication . Hugo Miguel Pereira Chambel; Pereira, António Manuel de JesusIn this document it will be described the architecture of an information system that was originated in an innovative idea based roots in joining two milestones of the social environment, tourism and technology. Separating the components then it will be described tourism, represented by tourism regions and the technology that allows navigation in small footpaths using Android mobile devices, which result on support of information and communication technologies to tourism and regions themselves.
- Accuracy versus complexity of MARG-based filters for remote control pointing devicesPublication . Rasteiro, Miguel ; Costelha, Hugo; Conde Bento, Luis; Assunção, PedroAlthough most current pointing devices rely on relative rotation increments, absolute orientation allows for a more intuitive interaction. However, this is difficult to implement in low-energy consumption devices since accurate fusion filters are computationally intensive. This work presents a comparative study of low-complexity filters and state-of-the-art orientation tracking systems, enabling to access complexity versus portability. A relevant set of different MARG units currently available on the market were studied under systematic tests and human subjective user analysis. Experimental results show that it is possible to obtain similar accuracy using low-complexity filters to the ones observed with state-of-the-art orientation tracking systems. © 2015 IEEE.