Repositório RCAAP

The deployment of information and communication technologies in vehicles and into the transportation infrastructure in general, holds the promise of significant improvements to traffic safety and efficiency. The ETSI ITS-G5 standard presents itself as a viable and already available solution, to enable such intelligent social and mobility scenarios in the near future, including cooperative and autonomous vehicle platooning. However, the usage of wireless communications in safety-critical scenarios poses several challenges, and their reliability and safety must be adequately tested and validated. To do this, the safety concerns and cost of relying on real vehicles is prohibitive for early deployments. A solution lies in the use of robotic platforms, since these are relatively cheaper and allow to partially test real platforms and components, as well as different control mechanisms. This work presents the development of a 1/10 scale Cooperative Platooning Robotic Testbed with such aim. Real ITS-G5 On Board Units (OBU) were integrated in the vehicles for communications support and a cooperative control algorithm that solely relies on communications was successfully implemented.

Home garden crops, small-scale agricultural systems for local food production, are becoming an integral part of the food supply chain in a number of developing countries and peri-urban areas of some developed regions. In this work, we propose a low-cost, monitoring and irrigation system which can be applied in household and local community gardens. The basic architecture consists of a sensing/actuation station based on commercial off-the-shelf hardware and a mobile application for the interaction with remote users. A key aspect of the system is the use of legacy text-messaging service as a mechanism to support alert and control operations for monitoring and irrigation. This feature enables widely available and highly-reliable connections between the cropland station and remote users without the need for new network infrastructure. We implemented a functional prototype of the system to check its effectivity in a small open-field area for tomatoes cultivation. The results show that water usage can be substantially improved if using both the actual information collected from the system and public tools for decision support in agriculture. We conclude that the proposed solution has a good prospect as an input for the design of more automated decision-strategies to be used in plant cultivation of a similar kind and/or of a larger scale.

Memory bus contention strongly relates to the number of main memory requests generated by tasks running on different cores of a multicore platform, which, in turn, depends on the content of the cache memories during the execution of those tasks. Recent works have shown that due to cache persistence the memory access demand of multiple jobs of a task may not always be equal to its worst-case memory access demand in isolation. Analysis of the variable memory access demand of tasks due to cache persistence leads to significantly tighter worst-case response time (WCRT) of tasks.In this work, we show how the notion of cache persistence can be extended from single-core to multicore systems. In particular, we focus on analyzing the impact of cache persistence on the memory bus contention suffered by tasks executing on a multi-core platform considering both work conserving and non-work conserving bus arbitration policies. Experimental evaluation shows that cache persistence-aware analyses of bus arbitration policies increase the number of task sets deemed schedulable by up to 70 percentage points in comparison to their respective counterparts that do not account for cache persistence.

In the Muslim community, the prayer (i.e. Salat) is the second pillar of Islam, and it is the most essential and fundamental worshiping activity that believers have to perform five times a day. From a gestures' perspective, there are predefined human postures that must be performed in a precise manner. However, for several people, these postures are not correctly performed, due to being new to Salat or even having learned prayers in an incorrect manner. Furthermore, the time spent in each posture has to be balanced. To address these issues, we propose to develop an artificial intelligence assistive framework that guides worshippers to evaluate the correctness of the postures of their prayers. This paper represents the first step to achieve this objective and addresses the problem of the recognition of the basic gestures of Islamic prayer using Convolutional Neural Networks (CNN). The contribution of this paper lies in building a dataset for the basic Salat positions, and train a YOLOv3 neural network for the recognition of the gestures. Experimental results demonstrate that the mean average precision attains 85% for a training dataset of 764 images of the different postures. To the best of our knowledge, this is the first work that addresses human activity recognition of Salat using deep learning.

Technology advances in microprocessor design have resulted in high device density and performance during the last decades. More components are fabricated on the chip die and millions, if not billions, of instructions can now be executed within microseconds. A consequence of this advancement is heat dissipation by the microprocessors. In this context, elevated on-chip temperature issues have become an important subject for the design of future generations of microprocessors, especially in avionics and automotive industries. In this paper, we address the scheduling problem of non-preemptive periodic tasks on a single processor platform under thermal-aware design. We assume that the tasks are scheduled by following any Fixed-Task-Priority (FTP) scheduler (e.g., Rate Monotonic (RM) or Deadline Monotonic (DM)) and we propose a unique framework wherein we capture both the temporal and thermal behavior of the system. Then, we present two new thermal-aware scheduling strategies, referred to as NP-HBC and NP-CBH, to keep the system temperature within specified parameters and we derive their respective schedulability analysis. Finally, we evaluate the performance of the proposed theoretical results through intensive simulations.

Digital technologies are ubiquitous in modern life. They mediate many of our daily actions, particularly those involving other humans, providing us information of all sorts and connectiveness with almost anything. This condition, in addition to the rises of artificial intelligence, the internet of things and quantum computers, has prompted many important discussions about the way humans and machines interact and relate (or should relate to each other in the near future). Yet, a common feeling of something “human” being lost is felt by many people. What are we losing and what´s the responsibility of the digital technologies? It is not an easy answer. I believe that in the past decade, the transformation of our “feeling of passing time” is perhaps one of the most noticeable traces of how computers affect our daily life. Old New Technologies #1 is an audiovisual installation proposing to merge old and new technologies to create a feeling of “slowing down the passage of time”. It does so by inviting individuals to pick up an old rotary telephone, to dial a number from a list and to listen and see an audiovisual postcard. Take your time, recover your time, feel your body. Enjoy. Breath.

This paper presents the methodology employed to create the sound installation Saving Shapes (2016-2018). Based on that, we will present some remarks about composing music for sound installations at outdoor places on exhibition for prolonged periods of time, particularly strategies to avoid audio loops. Our approach is based on three phases: (1) gather a wide range of phenomenological “information” from the place, mostly by performing soundwalks, taking notes and doing sound recordings (2) analyzing that “information” and composing music to be performed and installed at that specific place (3) periodically recreate the composition/installation using new “information” retrieved by repeating step number 1. Our research is mostly based and inspired on ideas from soundscape studies and artistic practices of well-known authors such as Murray Schafer (1977), Hildegard Westerkamp (1974), Barry Truax (2001), David Abram (1996) and Bernie Krause (2013). For our specific work and research, Westerkamp and Krause are two key figures. On the one hand, Westerkamp (1974) addresses the surrounding environment as a performing place to be experienced while one performs a soundwalk. She believes that such a “performance” (i.e. soundwalking) within complex soundscapes (e.g. outdoor locations) is a rich sonic experience, thus, we believe, interesting to create (and recreate) music compositions. Soundwalking became the central aspect of our creative and analytical methodology, understood here as a multifaceted activity to listen, record and devise music compositions; on the other hand, Krause defined biophony, geophony and antrophony as complementary spheres of the soundscape, thus, defining a clear theoretical and practical reference about the acoustic elements of a given place. Krause’s spheres of the soundscape, together with Westerkamp’s soundwalk, are essential to our methodology and they form the theoretical and practical basis of our proposed creative process. Saving Shapes (2016-2018) was composed for an outdoor space. We believe that outdoor spaces, as opposed to indoor spaces, are best suited for our proposed creative methodology. Outdoor spaces offer an infinitude of complexities that (might) transform and dialog with instrumental and electroacoustic sounds. Lastly, we will discuss the benefits of revisiting the same place to experience its particularities and meanings as a methodology, as opposed to using a computer to retrieve data in real time during the period of the installation. A lot of objects and narratives were constantly explored during a long period of time to instigate new (or old) connections between environmental sounds and the creative process. It materializes the multiple roles of soundwalking and the idiosyncrasy of the “human factor” to rebuild perspectives and transforming pre-existing compositions for a specific place.

Plantorumori, our research and art work, is about complicity with plants. Our aim is to use music as a conciliator to create subjective communication channels with nature, particularly with plants. The communication channels that we want to “open” with plants are, however, a utopia. We are dealing with entities that do not manifest themselves in ways we humans can easily perceive. We are atempting to understand how relationships could be outside the realm of logic, numerical truths or intersubjectivity. To accomplish this desire, we want to explore the opening of “communication channels” with plants using a wide range of technologies and interfaces to nurture a subjective relationship with nature and to integrate that “contribution” in musical performances.

A growing need for environmental awareness requires sensitive strategies to help us rethink the way interactions transform our habitat. This work proposes a musical approach to nourishing the bonds between elementary-school students and nature. Since plants and humans experience life in very different time frames, humans might mistakenly perceive plants as quiet and motionless living-beings. The ability to sense elements of their surroundings to which we are unaware of, makes plants invaluable allies towards a more conscious relationship with the planet we share. This work proposes that music has the potential to intermediate these interactions and provide meaningful experiences to the young participants by bringing to common ground digital technology, music and plants. Using sensors to collect data from the plant’s environment we shape musical features over time, encouraging children care of their own plant as it blossoms into its matured “musical form”. In addition, sound events might be triggered to reward positive behavior in the classroom. Students split responsibility for the plant assigned to their desk, which stimulates cooperation and companionship. Each individual plant then becomes part of and contributes to its class and school musical.

Recentemente tornei-me responsável pela área de Som na Escola Superior de Media Artes e Design (ESMAD), encarando pela primeira vez estudantes que, em princípio, não têm bases musicais nem tão pouco interesse assumido nessa arte (levando em conta a escola em que se inscreveram). Os currículos, em consonância com as bibliografias de referência sobre som no cinema e multimédia, espelham também essa ausência de “música” privilegiando o estudo técnico (e.g. áudio digital, microfones, pós- -produção áudio). Ora, acredito que o currículo destes estudantes não deve ser refém da aprendizagem técnica mas sim complementadas com experiências musicais que aflorem o sentido crítico e criativo. Nas palavras de Andreas Schleicher, diretor do departamento de Educação e Competências da OCDE, o mundo “já não recompensa as pessoas apenas por aquilo que sabem – o Google sabe tudo – mas por aquilo que conseguem fazer com isso”. Neste sentido, a criação livre e artística é especialmente importante promovendo competências criativas e preparando as pessoas para problemas que, porventura, hoje ainda nem existem. A ORCA (Orquestra de Robots, Computadores e Altifalantes) é uma atividade extra-curricular que num primeiro plano traz “música ao som” mas que, acima de tudo, é um espaço instigador da criatividade pela partilha humana e criação livre. A ORCA nasceu em janeiro deste ano e fazem parte o prof. de Som e três estudantes. O Projeto 1 é a nossa primeira manifestação pública e é constituída por um agregado robótico de objetos sonoros controlados por interfaces originais e internet, com estreia marcada no Intermediartes.

Over the last few years Companhia de Música Teatral (CMT) has been developing a series of original ideas that has designated as “artistic-educative constellations”. CMT's work is deeply rooted in music but explores links with other artistic languages and technology and proposes an intrinsic articulation with education (in a very broad sense). The CMT projects are a kaleidoscope of Performance pieces, Installations, Workshops, Publications and TransFormation activities and the piano has been central to many of these projects. One constellation in particular, Anatomia do Piano, has made the piano the “attractor” of a series of initiatives that connect the “main-stage” with the classroom, the science laboratory or the community. The installation Pianoscópio, part of this constellation, is the subject of this communication: it is based on the idea of “deconstructing” the piano, in order to contribute to a more profound understanding of music, creating an opportunity for discovery and expression. It is an experience that transforms the piano into a collective instrument, a sound installation/sculpture capable of producing sounds of a myriad of colours, a space to be inhabited by people and produce sound through their combined interaction. In this paper we report on the experience using the Pianoscópio in a wide range of situations, from workshops with children to concerts and recordings with professional musicians, science-based projects or projects with the community.

We present ​Soniferous Resonances​, an ongoing collection of electroacoustic composition pieces that intersect music, digital technologies and architecture. The creative impetus supporting this research is grounded in the interchange of the following two concepts: 1) the phenomenological exploration of the aural architecture [1], particularly the reverberation as a sonic effect [2] through music performance and 2) the real time sound analysis of both the performance and the reverberation (i.e. impulse responses) intervallic content — which ultimately leads to a generic control over consonance/dissonance (C/D). Their conceptual and morphological nature can be understood as sonic improvisations where the interaction of sound producing bodies (e.g. saxophone) with the real (e.g. performance space) and the imaginary (i.e. computer) acoustic response of a space results in formal elements mirroring their physical surroundings. Particular emphasis is given to spectromorphological manipulations by a large array of “contrasting” digital reverberations with extended control over the sound mass [3] and its musical interval content across a continuum between pitched and consonant to unpitched and dissonant sounds. Two digital applications developed by the authors are seminal in Soniferous Resonances​: Wallace [4] and MusikVerb [5]. The first is a navigable user-control surface that offers a fluid manipulation of audio signals to be convolved with several “contrasting” digital reverberations. The second offers refined (compositional) control over the interval content and/or C/D levels computed from the perceptually-inspired Tonal Interval Space [6] resulting in an automatically adaptation of harmonic content in real time. Soniferous Resonances​ aims at pushing the boundaries of musical performances that are formally tied to its surrounding space, as well as triggering new concepts and greater awareness about the sublime qualities of experiencing aural architecture.

We present Variações sobre Espaço #6, a mixed media work for saxophone and electronics that intersects music, digital technologies and architecture. The creative impetus supporting this composition is grounded in the interchange of the following two concepts: 1) the phenomenological exploration of the aural architecture (Blesse & Salter 2007) particularly the reverberation as a sonic effect (Augoyard & Torgue 2005) through music performance and 2) the real time sound analysis of both the performance and the reverberation (i.e. impulse responses) intervallic content — which ultimately leads to a generic control over consonance/dissonance (C/D). Their conceptual and morphological nature can be understood as sonic improvisations where the interaction of sound producing bodies (i.e. the saxophone) with the real (e.g. performance space) and the imaginary (i.e. computer) acoustic response of a space results in formal elements mirroring their physical surroundings.

O presente artigo pretende apresentar uma análise comparativa no que se refere aos distintos comportamentos das gerações, no que concerne à utilização da tecnologia em diferentes contextos do quotidiano em geral, e à informação sobre destinos turísticos, em particular. A investigação empírica pretende apresentar, relativamente à geração Z, e ao destino Porto, resultados sobre a influência dos recursos tecnológicos no grau de satisfação, face ao destino, nas fases pré-viagem e durante a viagem. Os resultados evidenciam que a tecnologia faz parte do modo de vida da Geração Z, na fase da pré-viagem e durante a viagem, confirmando assim que as tecnologias e a utilização da internet são decisivas na pesquisa de informações de viagem, reservas e pagamentos, durante a fase de preparação de uma viagem, pela Geração Z. Deverão, as DMO’s regionais e locais, assegurar a permanente atualização dos conteúdos de informação online e atualização das tecnologias no destino, particularmente, nos serviços turísticos (em todos os setores: alojamento, transportes, restauração, e atrações em geral), deverá estar sempre disponível, pela necessidade de obtenção de esclarecimentos sobre os destinos turísticos antes e durante da viagem, essencial à avaliação positiva da satisfação da experiência do consumidor.

Este número especial da RISTI é composto pelos trabalhos escritos em espanhol e em português aceites para apresentação e discussão na Conferência Internacional de Turismo, Tecnologias e Sistemas de 2020 (ICOTTS´20). A ICOTTS é uma conferência multidisciplinar com foco especial em novas tecnologias e sistemas no setor do turismo e realizou-se entre 29 e 31 de outubro de 2020. A ICOTTS´20 contou com o apoio da Universidade de Cartagena, em Cartagena de Índias - Colômbia, da Escola Superior de Hotelaria e Turismo do Politécnico do Porto - Portugal e da AISTI (Associação Ibérica de Sistemas e Tecnologias de Informação). A Conferencia Internacional de Turismo, Tecnologias e Sistemas é um fórum internacional para investigadores e profissionais do setor do turismo, que possibilita a discussão das mais recentes inovações, tendências e preocupações nas diversas vertentes do Turismo associado às Tecnologias e Sistemas de Informação. É um evento para profissionais do setor, em busca de soluções de tecnologia, onde académicos, especialistas em TI e gestores de empresas se encontram para discutir novas ideias que os ajudem a maximizar o potencial de negócios de turismo por meio da tecnologia. O Comité Científico da ICOTTS´20 é composto por um grupo multidisciplinar de 137 especialistas que avaliaram cerca de 190 trabalhos provenientes de 28 países, recebidos para cada um dos principais temas propostos para a conferência: a) Tecnologia em Turismo e Experiência Turística; b) Destinos inteligentes; c) Marketing Digital aplicado ao Turismo e Viagens; d) Tecnologias Móveis aplicadas ao Turismo Sustentável; e) Investigação na área do turismo para o fornecimento de soluções inovadoras para problemas sociais; f) Turismo, bem-estar e hospitalidade; g) Tecnologias da informação no turismo; h) Transformação digital dos negócios turísticos; i) Viagens para saúde e bem-estar; j) Tecnologias de Informação em Ecoturismo e Agroturismo; k) Tecnologias de Informação em Turismo Alimentar; l) Tecnologias da informação na educação e turismo educacional; m) eTurismo e Turismo 2.0; n) Big data e gestão de viagens e turismo; o) Robótica no turismo; p) Resiliência e Turismo; q) Turismo Negro; e r) Turismo militar. Os trabalhos aceites para apresentação e discussão na Conferência são publicados pela Springer e pela AISTI (esta revista) e serão submetidos à indexação pelo ISI, SCOPUS, ProQuest e/ou Google Scholar, entre outros. Agradecemos a todos aqueles que contribuíram para a realização da ICOTTS´20 (autores, comitês, organizadores de workshops e patrocinadores). Agradecemos profundamente seu envolvimento e apoio, que foram cruciais para o sucesso da conferência.

In multicore systems tasks running on one core may experience inter-task interference from tasks running on other cores. This inter-task interference is due to contention in using shared resources such as caches, system bus and the main memory. In this work, we focus on one of the major sources of cross-core interference in multicore systems, i.e., main memory. The idea is to allocate tasks to cores in a way that the total memory demand of all tasks executing at a time instant t is less than the minimum available memory bandwidth, i.e., DRAM min. The problem is formulated as a server-to-core mapping problem where each server constitute a set of tasks corresponding to an application. As mapping problems in multicore systems are NP-hard, we use different heuristic and meta-heuristic based approaches to find a feasible solution. Results show that our approach can perform well in multicore systems with ≤ 8 processing cores with the memory demand of each server upper bounded by DRAM min/2.

In this paper we approach the problem of Mixed Criticality (MC) for probabilistic real-time systems where tasks execution times are described with probabilistic distributions. In our analysis, the task enters high criticality mode if its response time exceeds a certain threshold, which is a slight deviation from a more classical approach in MC. We do this to obtain an application oriented MC system in which criticality mode changes depend on actual scheduled execution. This is in contrast to classical approaches which use task execution time to make criticality mode decisions, because execution time is not affected by scheduling while the response time is. We use a graph-based approach to seek for an optimal MC schedule by exploring every possible MC schedule the task set can have. The schedule we obtain minimizes the probability of the system entering high criticality mode. In turn, this aims at maximizing the resource efficiency by the means of scheduling without compromising the execution of the high criticality tasks and minimizing the loss of lower criticality functionality. The proposed approach is applied to test cases for validation purposes.

Safety-critical cooperative vehicle applications such as platooning, require extensive testing, however, the complexity and cost involved in this process, increasingly demands for realistic simulation tools to ease the validation of such technologies, helping to bridge the gap between development and real-word deployment. In this paper we propose a realistic co-simulation framework for cooperative vehicles, that integrates Gazebo, an advanced robotics simulator, with the OMNeT++ network simulator, over the Robot Operating System (ROS) framework, supporting the simulation of advanced cooperative applications such as platooning, in realistic scenarios.

Traffic congestion is an issue regarding the vitality of cities and the welfare of citizens. Transportation systems are using various technologies to allow users to adapt and make different decisions towards transportation modes. Modification and improvement of these systems affect the commuters' perspective and social welfare. In this study, the effect of road flow equilibrium on commuters' utilities with different types of transportation modes will be discussed. A simple network with two modes of transportation will be illustrated and three different cost policies were considered to test the efficiency of reinforcement learning in commuters' daily trip decision-making regarding time and mode. The artificial society of agents is simulated to analyse the results.

This paper presents a framework for medium access control (MAC) and physical (PRY) cross-layer security design of wireless avionics intra-communications (WAICs). The paper explores the different options based on the latest results of MAC-PRY cross-layer design and the available standard technologies for WAICs. Particular emphasis is given to solutions based on multiple-input multiple-output (MIMO) systems and recent developments towards a wireless technology with ultra-low latency and high reliability in the context of 5G and machine-type traffic support. One major objective is to improve WAICs technology and thus match the real-time, reliability and safety critical performance of the internal aeronautics bus technologies (e.g., ARINC 664). The main identified vulnerabilities and potential solutions are explored, as well as their impact on system design complexity and feasibility for wireless networks on-board aircraft. The solutions are presented in the context of the European project SCOTT (secure connected trustable things) using the recently released reference architecture for trusted IoT systems. Other aspects of SCOTT such as trust, privacy, security classes, and safety are also discussed here for the aeronautics domain.