INESCC-DL - Artigos em Livros de Actas
URI permanente para esta coleção:
Navegar
Percorrer INESCC-DL - Artigos em Livros de Actas por Domínios Científicos e Tecnológicos (FOS) "Engenharia e Tecnologia::Engenharia Eletrotécnica, Eletrónica e Informática"
A mostrar 1 - 10 de 15
Resultados por página
Opções de ordenação
- 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.
- Blind Guide: An Ultrasound Sensor-based Body Area Network for Guiding Blind PeoplePublication . Pereira, António; Nunes, Nelson; Vieira, Daniel; Costa, Nuno; Fernandes, Hugo; Barroso, JoãoWireless Sensor Networks, in particular Wireless Body Area Networks, is a technology suggested by the research community as allowing elderly people, or people with some kind of disability, to live in a safer, responsive and comfortable environment while at their homes. One of the most active threats to the autonomous life of blind people is the quantity and variety of obstacles they face while moving, whether they are obstacles in the footpath or obstacles coming out from the walls of buildings. Hence, it is necessary to develop a solution that helps or assists blind people while moving either in indoor or outdoor scenarios, simultaneously allowing the use of the use of white cane or the Seeing Eye dog. In this article, the authors propose the use of an ultra-sound based body area network for obstacle detection and warning as a complementary and effective solution for aiding blind people when moving from place to place. According to the cost estimates of the solution and to the negligible setup time, this could be a real effective complementary solution for blind people.
- Complexity Analysis of a Business Process Automation: Case Study on a Healthcare OrganizationPublication . Martinho, Ricardo; Rijo, Rui Pedro Charters Lopes; Nunes, AnaHealthcare organizations have been struggling to get Business Process Management (BPM) and associated Information and Communication Technologies (ICT) properly aligned to improve their patients' service and quality of care. Nevertheless, the highly structured nature of larger organizations such as hospitals hampers this alignment, and commonly ICT is applied to isolated tasks or fragments of processes. In this paper, we present and discuss the results, in terms of complexity, of the introduction of a new scheduling system within the medical appointment and exam business processes of a large hospital. During the case study, we began by modelling the processes using the Business Process Modelling and Notation (BPMN) standard. We then used abstract metrics to compare the complexity between old (before the introduction of the scheduling system) and new processes, and interpreted the obtained results. Finally, we derived important conclusions that will help guide us in further business process optimization endeavors.
- 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.
- DOTS: Drift Oriented Tool SystemPublication . Antunes, Mário; Costa, Joana; Silva, Catarina; Bernardete RibeiroDrift is a given in most machine learning applications. The idea that models must accommodate for changes, and thus be dynamic, is ubiquitous. Current challenges include temporal data streams, drift and non-stationary scenarios, often with text data, whether in social networks or in business systems. There are multiple drift patterns types: concepts that appear and disappear suddenly, recurrently, or even gradually or incrementally. Researchers strive to propose and test algorithms and techniques to deal with drift in text classification, but it is difficult to find adequate benchmarks in such dynamic environments. In this paper we present DOTS, Drift Oriented Tool System, a framework that allows for the definition and generation of text-based datasets where drift characteristics can be thoroughly defined, implemented and tested. The usefulness of DOTS is presented using a Twitter stream case study. DOTS is used to define datasets and test the effectiveness of using different document representation in a Twitter scenario. Results show the potential of DOTS in machine learning research.
- eServices - Service Platform for Pervasive Elderly CarePublication . Marcelino, Isabel; Laza, Rosalía; Domingues, Patrício; Gómez-Meire, Silvana; Pereira, AntónioIn this paper, we present a solution to improve elderly’s quality of life. eServices – Service platform for pervasive elderly care was designed to aggregate several services developed to meet senior population’s needs. It monitors basic life signs, environment variables and uses personal location technology. Besides sensor services, eServices solution contains digital services align with emotional and social care needs. Due to target population specifications, eServices was designed to be as simple and accessible as possible in order to remove technological barriers. One of eServices major features is to detect imminent danger situations, act accordingly. It also collects the data from the sensors, location routines and from the interactions between the elderlies and the provided services to detect behavior deviations in order to act preventively. The platform was tested by seniors in real scenario. The experimental results demonstrated that the proposed platform was well accepted and easy to use by seniors, which demonstrated enthusiasm and interest in daily bases use.
- An Evolutionary Algorithm based on an outranking relation for sorting problemsPublication . Oliveira, Eunice; Antunes, Carlos HenggelerA new approach for using the preferences elicited from a Decision Maker (DM) into the operational framework of an Evolutionary Algorithm (EA) is presented. The preference representation is achieved using the parameters and principles of the ELECTRE TRI method devoted to the sorting problem. The outranking relation is used to replace the non-dominance relation in the usual operators in the EA (crossover, mutation and selection operator). The aim of this approach is to focus the search on the region of interest defined by the DM's preferences and consequently restrict the number of solutions in the Pareto-optimal front to be subject to further screening. This aspect is particularly important when dealing with problems that lead to a large number of non-dominated solutions.
- Influence of a SVC on AC Arc furnaces harmonics, flicker and unbalance. Measurement and analysis.Publication . Donsión, M. P.; Güemes, J. A.; Oliveira, F.An AC arc furnace is an unbalanced, nonlinear and time varying load, which can cause many problems to power system quality. Different studies on arc furnaces harmonics analysis can be found in the bibliography on the topic; however, it is very difficult obtain an exact model that takes into account all the parameters that have influence on the process, therefore it is necessary to take measurements under different conditions. In this paper we'll present the harmonic distortion, flicker and unbalance results and conclusions on three different measurement campaigns in an iron and steel industry (SNL) with an AC arc furnace of 83 MW (170 TM) with a transformer of 120 MVA connected with a dedicated power line of 220 kV (55 km) to the Carregado Substation, where there are another other branches that connect industrial and domestic consumers.
- Open Source para a Administração Pública: J2Gov - Joomla to governmentPublication . Martins, Pedro Matos; Pereira, AntónioThis project is the development of a component for the Content Management System Joomla, titled J2Gov (Joomla to government), which can cater for the requirements of public administration bodies, which relate directly to the public. In a single platform, a tool to provide an interface for online services, presential services, document management and control and measurement times and performances. In this context, this project was developed as a way to meet the needs of public administration, regardless of their size, financial capacity or technical expertise of its human resources in the field of information technology.
- Point Cloud Alignment for Deposited Material Assessment in Tunnel EnvironmentsPublication . Teixeira, Abel; Costelha, Hugo; Neves, Carlos; Bento, Luis CondeThe assessment of deposited material in tunnel reinforcement operations can be performed using a 3D model generated from multiple scans. For this purpose, an accurate alignment of the scanned models is required. Aligning existing structure model with data scanned after surface deformations can be challenging, particularly if reference markers are not available or were displaced. For scenarios where the surrounding structure is largely changed, certain procedures can be adapted when processing the scanned data to achieve consistent alignment between scanned and reference structure models. This work proposes a methodology to cope with these situations, analysing the impact of different approaches. Experiments were performed in a realistic scenario related with shotcrete of railway tunnels wall surfaces, with the results showing the applicability of the developed work. The proposed procedure relies in highlighting the importance of specific points that describe the same feature in the reference and aligning PC. The proposed methodology achieved an RMS difference of 0.0173 m, which lead to a drastic improvement in the point cloud alignment compared to the use of standard ICP algorithm without data preprocessing, which achieved 0.0518 m in the studied use-case.
