Abstract
In this work, we present the design, laboratory tests, and the field trial results of a power-over-fiber (PoF) low power instrument transformer (LPIT) for voltage and current measurements in the medium voltage distribution networks. The new proposed design of this power-over-fiber LPIT aims to overcome the drawbacks presented by the previous technologies, such as the continuous operation (measuring and data transmission) for a wide current range conducted in the medium voltage transmission lines, damage due to lightning strikes, accuracy dependency on vibration, position and temperatures. The LPIT attends the accuracy criteria of IEC 61869-10 and IEC 61869-11 in terms of current and voltage accuracy and it attends the practical criteria adopted by Utilities companies including voltage measurements without removing the coating of the covered conductors. The PoF based LPIT was developed to be applied at 11.9 kV, 13.8 kV, and 23.0 kV phase-to-phase nominal voltages, and in two current ranges 1.25–30 A and 37.5–900 A. The digital data transmission of current, voltage, and temperature from the sensing unit to the processing unit uses a special synchronism technique and it is performed by two 62.5 µm multimode fibers in 850 nm. The optical powering in 976 nm is also performed by one 62.5 µm multimode fiber from the processing unit to the sensor unit. We presented all details of the sensor design and its laboratory characterization in terms of accuracy and temperature correction. We also presented the results of field tests of the sensor made in two different conditions: in a standard distribution network and an experimental hybrid fiber/power distribution network. We believe that these studies aim to incorporate optical fiber and devices, digital technologies, communications systems in electrical systems driving their evolution.

Abstract
The rise of social media and the explosion of digital news in the web sphere have created new challenges to extract knowledge and make sense of published information. Automated timeline generation appears in this context as a promising answer to help users dealing with this information overload problem. Formally, Timeline Summarization (TLS) can be defined as a subtask of Multi-Document Summarization (MDS) conceived to highlight the most important information during the development of a story over time by summarizing long-lasting events in a timely ordered fashion. As opposed to traditional MDS, TLS has a limited number of publicly available datasets. In this paper, we propose TLS-Covid19 dataset, a novel corpus for the Portuguese and English languages. Our aim is to provide a new, larger and multi-lingual TLS annotated dataset that could foster timeline summarization evaluation research and, at the same time, enable the study of news coverage about the COVID-19 pandemic. TLS-Covid19 consists of 178 curated topics related to the COVID-19 outbreak, with associated news articles covering almost the entire year of 2020 and their respective reference timelines as gold-standard. As a final outcome, we conduct an experimental study on the proposed dataset over two extreme baseline methods. All the resources are publicly available at https://github.com/LIAAD/tls-covid19. © 2021, Springer Nature Switzerland AG.

Abstract
This paper aims to explore the impact of sense of presence and cybersickness on the users' expectancy and perceived similarity between virtual and the corresponding real environments. Two virtual reality setups were tested (non-immersive and immersive) to achieve further conclusions. This research encompassed a quantitative analysis using data collection based on questionnaires, applied to a sample of 45 participants. A virtual experience was conducted (to explore users' cybersickness and sense of presence), followed by a visit to the actual real sites (to determine the degree of perceived similarity between the virtual and the corresponding real environment and if their expectations were fulfilled). Our results show a positive correlation between the global sense of presence and perceived similarity and users' expectancy for the non-immersive VR setup. A positive correlation was also found between the global cybersickness on both perceived similarity and users' expectancy for the immersive VR setup. Implications of such results for virtual tourism are discussed.

Abstract
In this paper we present the latest results on the design, fabrication and test of stand-alone photonic devices devoted to ultra-high bandwidth wireless access networks operating near the Terahertz (THz) band. We review the sub-THz photonics-based technology devices developed as part of the TERAPOD project, comprising the monolithically integrated Silicon Nitride photonic integrated circuit for phase distribution, the 1x4 array of integrated Uni-Travelling Carrier Photo-Diodes (UTC-PDs) and the radiative design of the high-frequency four element linear patch antenna array based on Benzocyclobutene (BCB) layers. We also report the suitability to assemble all those components in a robust small-form factor hybrid package.

Abstract
Pastoral activities bring several benefits to the ecosystem and rural communities. These activities are already carried out daily with goats, cows and sheep in Portugal. Still, they could be better applied to take advantage of their benefits. Most of these pastoral ecosystem services are not remunerated, indicating a lack of making these activities more attractive to bring returns to shepherds, breeders and landowners. The monitoring of these activities provides data to value these services, besides being able to indicate directly to the shepherds’ routes to drive their flocks and the respective return. There are devices in the market that perform this monitoring, but they are not adaptable to the circumstances and challenges required in the Northeast of Portugal. This work addresses a system to perform animals tracking, and the development of a test platform, through long-range technologies for transmission using LoRaWAN architecture. The results demonstrated the use of LoRaWAN in tracking services, allowing to conclude about the viability of the proposed methodology and the direction for future works.

Abstract
This research examines temporal continuities in videogames-the passing of time regardless of player action-and players' understanding of it, taking into account videogame and media theory. It presents a chronology of schools of thought and an analysis of the application of the theory to two case studies, to determine the motives behind players' actions over time. Subjects played two videogames of different genres, and an analysis of mixed nature revealed a lack of consensus about who is in control of the passing of time in the narrative of videogames. Results demonstrate the ambiguity in the awareness of the passing of time, showing that: (1) players distinguish narrative time and story time; (2) time can be studied through dynamic problems presented to players; (3) narrative cycles inform scene segmentation. The study corroborates previous hypotheses about the resolving of conflicts bringing an end to the narrative, thus also to the temporal continuity. Data shows evidence of the possibility of analysing time in videogames through some of the theories and frameworks tested.