Unidade de Investigação - CIIC - Computer Science and Communication Research Centre
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- 2ARTs: A Platform for Exercise Prescriptions in Cardiac Recovery PatientsPublication . Pereira, Andreia; Martinho, Ricardo; Pinto, Rui; Rijo, Rui; Grilo, CarlosDue to limited access, increasing costs and an ageing population, the global healthcare system faces significant coverage problems that call for innovative approaches. Health professionals are actively seeking alternative methods to provide care to an increasingly needy population, without increasing human effort and associated costs. eHealth platforms, which use technology to provide patient care, are emerging as transformative solutions for addressing these problems. This study is centered on the demand for a Decision Support System (DSS) in cardiology to enable doctors to prescribe individualized care inside Cardiac Rehabilitation Programmes (CRPs). The 2ARTs project’s main objective is to include a cardiac rehabilitation platform with a DSS within the hospital infrastructure. This DSS uses models to classify patients into different groups, delivering crucial information to assist with decisions regarding treatment. Regarding the DSS, Principal Component Analysis (PCA) emerged as a standout technique for dimensionality reduction, due to its interoperability with clustering algorithms and superior evaluation metrics. The most appropriate clustering technique was determined to be the K-means algorithm, which was supported by the experts analysis. In accordance with the goals of the 2ARTs project, this integration of PCA and K-means provides meaningful insights that improve reasoned decision-making.
- 3D fast convex-hull-based evolutionary multiobjective optimization algorithmPublication . Zhao, Jiaqi; Jiao, Licheng; Liu, Fang; Basto-Fernandes, Vitor; Yevseyeva, Iryna; Xia, Shixiong; Emmerich, Michael T.M.The receiver operating characteristic (ROC) and detection error tradeoff (DET) curves have been widely used in the machine learning community to analyze the performance of classifiers. The area (or volume) under the convex hull has been used as a scalar indicator for the performance of a set of classifiers in ROC and DET space. Recently, 3D convex-hull-based evolutionary multiobjective optimization algorithm (3DCH-EMOA) has been proposed to maximize the volume of convex hull for binary classification combined with parsimony and three-way classification problems. However, 3DCH-EMOA revealed high consumption of computational resources due to redundant convex hull calculations and a frequent execution of nondominated sorting. In this paper, we introduce incremental convex hull calculation and a fast replacement for non-dominated sorting. While achieving the same high quality results, the computational effort of 3DCH-EMOA can be reduced by orders of magnitude. The average time complexity of 3DCH-EMOA in each generation is reduced from to per iteration, where n is the population size. Six test function problems are used to test the performance of the newly proposed method, and the algorithms are compared to several state-of-the-art algorithms, including NSGA-III, RVEA, etc., which were not compared to 3DCH-EMOA before. Experimental results show that the new version of the algorithm (3DFCH-EMOA) can speed up 3DCH-EMOA for about 30 times for a typical population size of 300 without reducing the performance of the method. Besides, the proposed algorithm is applied for neural networks pruning, and several UCI datasets are used to test the performance.
- 3D PARTICLE SYSTEMS FOR AUDIO APPLICATIONSPublication . Fonseca, NunoAlthough particle systems are well know for their use in computer graphics, their application in sound is very rare or almost non-existent. This paper presents a conceptual model for the use of particle systems in audio applications, using a full rendering system with virtual microphones: several virtual particles are spread over a virtual 3D space, where each particle reproduces one of the available audio streams (or a modified version), and the overall sound is captured by virtual microphones. Such system can be used on several audio-related areas like sound design, 3D mixing, reverb/impulse response design, granular synthesis, audio up-mixing, and impulse response up-mixing.
- 802.21-MPA-IMS ArchitecturePublication . Rodrigues, Carlos Miguel de Jesus; Rabadão, Carlos; Pereira, AntónioMobility has become a keyword nowadays with the evolution of mobile devices market and proliferation of realtime services. IP Multimedia Subsystem (IMS) is a single, standardized service framework that supports voice, video, data and messaging services, but does not provide seamless mobility for packet based sessions. This paper purposes an IMS architecture with IEEE 802.21 and media-independent pre-authentication (MPA) integrated. IEEE 802.21 can enable this seamless mobility in IMS and, additionally, MPA provides a secure handover optimization scheme, reducing, as a consequence, handover latency. The main goal of this architecture is to provide seamless and secure handovers between different access technologies in an IMS-based environment.
- Abordagem baseada em Algoritmos Genéticos para deteção de vulnerabilidades de SQL Injection em Aplicações Web PHPPublication . Baptista, Kevin; Bernardino, Anabela Moreira; Bernardino, Eugénia MoreiraHoje em dia, existe uma maior preocupação com a segurança no desenvolvimento de aplicações web. No entanto, ainda existem muitos ataques a este tipo de aplicações, perpetuados por hackers que se aproveitam das vulnerabilidades destas aplicações. Estas vulnerabilidades podem estar associadas a inúmeros fatores, desde configurações incorretas, falhas nas políticas de segurança, sistemas ou componentes desatualizados ou problemas diretamente associados ao código desenvolvido. Os ataques a aplicações web tem como resultado perda de informação privilegiada. Para mitigar este problema, existem varias ferramentas automatizadas que permitem auxiliar profissionais da área a identificar estas vulnerabilidades. No entanto, manter estas ferramentas atualizadas com a evolução tecnológica tem-se demonstrado um desafio. Neste artigo, propomos uma abordagem para detetar vulnerabilidades de SQL Injection no código-fonte de varias aplicações web PHP, usando Algoritmos Genéticos (AG). Os resultados obtidos mostram a eficiência do AG em relação a outras ferramentas existentes.
- ACCEPT: Web Applications for visualization and analytics of shop floor dataPublication . Godinho, Eduardo Miguel Ascenso; Piedade, Maria BeatrizNo contexto atual da Indústria 4.0 e do controlo metrológico de produtos pré-embalados, procura-se que os dados provenientes de chão de fábrica sejam recolhidos de forma automática e que diferentes tipos de dispositivos digitais tenham acesso aos mesmos dados de forma ubíqua. Pretendeu-se desenvolver e integrar aplicações Web no sistema ACCEPT, sistema que permite a recolha, armazenamento, visualização e análise de dados de chão de fábrica. Neste artigo é descrito o processo de desenvolvimento das aplicações ACCEPT Quality Hub e ACCEPT Analytics e a sua integração neste sistema.
- Accessible software development: a conceptual model proposalPublication . Silva, João Sousa e; Gonçalves, Ramiro; Branco, Frederico; Au‑Yong‑Oliveira, Manuel; Martins, José; Pereira, AntónioEqual access to all software and digital content should be a reality in the Digital Era. This argument is something defended both by existing regulations, norms and standards, and also business organizations and governments. Despite this acknowledgement, the reality is still far from the desired equality. For certain groups of disabled or impaired citizens, such as the visually impaired, the existence of e-accessibility compliance represents an opportunity to integrate, in a more simple and straightforward manner, their societies. Despite the existing poor results on e-accessibility compliance, the mentioned citizens insist on using digital devices in their daily lives. Even though, in the last decade, multiple standards and regulations have been published towards indicating how to develop accessible digital user interfaces, there are still two major issues surrounding its implementation: the complexity and disparity of the documents containing the abovementioned norms, and also the lack of e-accessibility know-how by software experts. With this in mind, a proposal for an accessible software development model that encompasses e-accessibility incorporation as one of the development process activities has been presented. This model might represent a very interesting support tool for software development organizations and a novel resource for learning and training institutions to be able to improve their computer science and informatics students’ skills on e-accessibility.
- Advanced technologies for shoe sole productionPublication . Spahiu, Tatjana; Almeida, Henrique; Ascenso, Rita M. T.; Vitorino, Liliana; Marto, AnabelaAdvanced technologies for modelling and production are an important part in the whole process of product manufacturing. These advancements have changed the way of product development and play an important role in customization. In the footwear industry, as in any other industry, the use of these technologies is widely spread. Footwear comfort is one of the main selection criteria for purchase. Considering this fact, a case study of different steps for shoe designing according to individual foot shape will be presented. Taking into consideration the aesthetics of the sole and in a more sustainable view, through topological optimization reducing of material wastage for sole production will be presented. By means of the topological optimization in the shoe design process, sole optimization is realized. As a part of personalization, feet’s plantar pressure maps taken from 1 participant gave a better explanation of weight distribution of each foot. Following, sole personalization according the plantar pressure maps for each foot gives the possibility to obtain the best least material design according to the feet’s pressure while maintaining biomechanical performance.
- AMIGA - An Interactive Musical Environment for GerontechnologyPublication . Reis, Lee Scott; Reis, Gustavo; Barroso, João; Pereira, AntónioBenefits provided by music in humans have been reinforced through several studies, mainly by active participation in musical therapy sessons, with surprising results in physical and psychological rehabilitation. However, all the previous implemented approaches require specialized hardware to function and complex configurations to set-up. We define a computational system focused on the elderly to allow musical expressiveness through motion, solely using the resources available in an ordinary home computer. To evaluate our approach, we developed a prototype and piloted acceptance tests on several senior citizens, with an average age of eighty-three. Our experiments showed high levels of interest from the senior citizens, denoting positive capabilities of well-being and life quality enrichment. The performed experiments have also shown that an ordinary computer is capable of performing the proposed methodology, without any restriction.
- Analyzing TikTok from a Digital Forensics PerspectivePublication . Domingues, Patricio; Nogueira, Ruben; Francisco, José Carlos; Frade, MiguelTikTok is a major hit in the digital mobile world, quickly reaching the top 10 installed applications for the two main mobile OS, iOS and Android. This paper studies Android's TikTok application from a digital forensic perspective, analyzing the digital forensic artifacts that can be retrieved on a post mortem analysis and their associations with operations performed by the user. The paper also presents FAMA (Forensic Analysis for Mobile Apps), an extensible framework for the forensic software Autopsy, and FAMA's TikTok module that collects, analyzes, and reports on the main digital forensic artifacts of TikTok's Android application. The most relevant digital artifacts of TikTok include messages exchanged between TikTok so-called ``friends'', parts of the email/phone number of registered users, data about devices, and transactions with TikTok's virtual currency. One of the results of this research is the set of forensic traces left by users' transactions with TikTok's in-app virtual currency. Another result is the detection of patterns that exist in TikTok's integer IDs, allowing to quickly link any 64-bit TikTok's integer ID to the type of resources -- user, device, video, etc. -- that it represents.