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  • Using text mining to diagnose and classify epilepsy in children
    Publication . Luis Pereira; Rijo, Rui; Silva, Catarina; Agostinho, Margarida
    Epilepsy diagnosis can be an extremely complex process, demanding considerable time and effort from physicians and healthcare infrastructures. Physicians need to classify each specific type of epilepsy based on different data, e.g., types of seizures, events and exams' results. This work presents a text mining approach to support medical decisions relating to epilepsy diagnosis and classification in children. We propose a text mining process that, using patient medical records, applies ontologies and named entities recognition as preprocessing steps, then applying K-Nearest Neighbors as a white-box lazy method to classify each instance. Results on real medical records suggest that the proposed framework shows good performance and clear interpretations, albeit the reduced volume of available training data.
  • Os Desafios Web no Processo Formativo - O Caso de Estudo da humansoft
    Publication . Sousa, Mayelson de; Gonçalves, Alexandrino
    A constante evolução das tecnologias web tem originado o aparecimento de plataformas que facilitam a gestão das tarefas dos utilizadores nos dias de hoje. No sentido de maximizar a satisfação do cliente e disporem de soluções de acordo com os padrões de atuais do mercado, as empresas devem adaptar os seus produtos, com particular enfoque nas soluções web-based, com vista a potenciar a usabilidade e a fluidez do seu uso. Neste sentido, este artigo apresenta um caso de estudo real, de desenvolvimento web na empresa humansoft, onde foram desenvolvidos diversos módulos relativos aos dois principais produtos da empresa, o humantrain, que é um sistema de gestão do processo formativo, e o humanportal, que é uma aplicação web que permite a interoperabilidade entre o humantrain e a web. Ambas as aplicações permitem às entidades formadoras e/ou empresas rentabilizarem a gestão dos seus recursos tanto ao nível pedagógico como financeiros.
  • Performance analysis of AES encryption operation modes for IoT devices
    Publication . Serra, Luís Filipe Dias; Gonçalves, Pedro Gonçalo Baptista; Frazão, Luís Alexandre Lopes; Antunes, Mário João Gonçalves
    Daily activities have been increasingly supported by intelligent devices and applications. Smart devices are constantly communicating through the Internet of Things (IoT) networks, either by sending collected data and notifying the actions taken or by receiving instructions for actions to be taken. Most of this communication requires the confidentiality of data through the usage of encryption algorithms, being the Advanced Encryption Standard (AES) algorithm one of the most used. However, how do the operation modes of AES algorithm perform in a resource-constraint device? This paper aims to evaluate the impact on the time to encrypt and decrypt different sized messages in IoT devices when using each one of the five AES modes of operation and the three key sizes defined. The test scenario was implemented using two programming languages, running on a Raspberry Pi device. The results achieved infers that Python was quicker and had a more homogeneous result set than JavaScript implementation in most AES operation modes. These results help to understand the trade-off between IoT devices' security needs and delays in communication caused by the selection of the AES algorithm operation mode.
  • An end-to-end cryptography based real-time chat
    Publication . Melo, Tiezer; Barros, António; Antunes, Mário; Frazão, Luís
    Confidentiality protects users' data from digital eavesdroppers when traveling through the Internet. Confidentiality is complex and costly, especially on applications that involve communication and data exchange between multiple users. Cryptography has been the most used medium to achieve confidentiality, being the greatest challenge the sharing of a secret key to a group of people in a safe and effective way. This paper presents a chat application that implements an innovative way of sending messages with end-to-end encryption, in real-time, with a dynamic key store, and without the existence of data persistence. The application stands out from the others by the fact that it innovates the way the keys are shared with multiple users.
  • An easy-to-use tool to inject DoS and spoofing networking attacks
    Publication . Almeida, Rafaela; Pacheco, Vasco; Antunes, Mário; Frazão, Luís
    Computer network attacks are vast and negatively impact the infrastructure and its applicational services. From a cyber offensive and defensive perspective, there are a plethora of tools to craft and inject customized malicious packets in the network and exploit operating systems and application vulnerabilities. Those tools are however hard to operate by practitioners with less knowledge on networking fundamentals and students in the early stage of their studies. This paper proposes an easy-to-use application tool that can produce customized Denial of Service (DoS) and spoofing attacks. It was developed in Python and takes advantage of scapy library to process and inject network packets. A set of experiments was made, and the results obtained show the efficiency and accuracy of the attacks, by impairing the proper functioning of the victim's machines.
  • Phenomena simulations for degradation prediction of cultural heritage buildings
    Publication . Serrano, Francisco; Serrano, João; Ribeiro, Pedro; Gonçalves, Alexandrino; Grilo, Carlos; Rodrigues, Nuno; Hipólito-Correia, Virgílio
    Predicting buildings degradation and erosion by natural and artificial phenomena has been an unexplored area. In this article is presented natural and artificial phenomena simulations applied to a tridimensional model, using physics mechanics, created algorithms and using materials, which aims to be used to predict buildings level of destruction in the next years.
  • Exploring Pareto scale mixtures
    Publication . Felgueiras, Miguel; Santos, Rui
    Pareto scale mixtures can be used to obtain distributions with heavier tails. An explanation of this model properties is provided, together with a discussion about the parameters estimation. Finally, a real data application is presented, consisting in the larger earthquakes seismic moment modeling.
  • Pseudo-convex mixtures
    Publication . Felgueiras, Miguel; Martins, João; Santos, Rui
    Allowing weights w∈]−1;1]\{0}, pseudo-convex mixtures increase usual mixtures flexibility. The finite mixtures with negative components are investigated for distribution families closed under minimization. The main purpose is to define these mixtures and to study their properties.
  • Discrete Compound Tests and Dorfman’s Methodology in the Presence of Misclassification
    Publication . Santos, Rui; Martins, João Paulo; Felgueiras, Miguel
    Compound tests can be used to save resources for classification or estimation purposes in clinical trials and quality control. Nevertheless, the methodologies that are usually applied are restricted to qualitative group tests. Moreover, when quantitative compound tests are applied the problem is to ascertain whether the amount of some substance of any individual in the group is greater or lower than a prefixed threshold. An overview of the applications of the discrete compound tests highlights the advantages (to save resources) and disadvantages (higher probability of misclassification), and suggests criteria to assess the suitability of applying Dorfman’s methodology.
  • @Sensor - Mobile application to monitor a WSN
    Publication . Moreira, Nuno; Venda, Marco; Silva, Catarina; Marcelino, Luis; Pereira, António
    Due to the growth of potential of Wireless Sensor Networks (WSN), now becomes possible to use this technology in various new generation services such as monitor environment characteristics like temperature, humidity, among others. WSNs are emerging as a new paradigm, gathering information in a collaborative way, where independent sensor nodes collect and share information. In the last few years ubiquitous computing popularity has grown considerably, ambient intelligence and home automation systems are having a good public acceptance. In this context, we developed a mobile application to remotely monitor one WSN, installed at a customer's home. The application's main goal is to interact with a WSN, allowing a user to consult sensor states and receive sensor alerts. Sensor alerts will be received, in case a sensor's threshold value, exceeds the limit. Therefore the user will be notified whenever there are changes in the WSN. Apart the WSN, a base station is also needed for keeping the state of the WSN, store sensor's information and enable communication between the WSN and the developed mobile application via Web Services. This way and having a network connection, the user can check the state of any WSN component, anytime, anywhere. The Android platform was chosen to implement our application, since it is having a great acceptance and continued growth in the mobile market.