Browsing by Issue Date, starting with "2021-11-18"
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- Cooperative vehicular systems: crossroad management through visible lightPublication . Vieira, Manuel Augusto; Vieira, Manuela; Louro, Paula; Vieira, PedroInformation and communication technologies enable optoelectronic cooperative vehicular systems with bi-directional communication, where vehicles communicate with other vehicles, road infrastructures, traffic lights, and vulnerable road users. We use the concept of request/response for the management of a trajectory in a two-way-two-way traffic lights controlled crossroad, using visible-light communication (VLC). The connected vehicles receive information from the network (Infrastructure to Vehicle, I2V), interact with each other (Vehicle to Vehicle, V2V) and with the infrastructure (Vehicle to Infrastructure, V2I), using a request distance and pose estimation concept. In parallel, an intersection manager (IM) coordinates the crossroad and interacts with the vehicles (I2V) using the response distance and the pose estimation concepts. The communication is performed through VLC using the street lamps and the traffic signaling, to broadcast the information. Data are encoded, modulated, and converted into light signals emitted by the transmitters. Tetra-chromatic white sources are used, providing a different data channel for each chip. As receivers and decoders, SiC wavelength division multiplexer (WDM) devices, with light filtering properties, are considered. A simulated vehicle-to-everything (V2X) traffic scenario is presented, and a generic model of cooperative transmission is established. The primary objective is to control the arrival of vehicles to the intersection and schedule them to cross over at time instants that minimize delays. A phasing traffic flow is developed as a proof of concept (PoC). The simulated/experimental results confirm the cooperative VLC architecture. Results show that the communication between connected cars is optimized using a request/response concept and that pose analysis is an important issue to control driver’s behavior in a crossroad. The block diagram conveys that the vehicle’s behavior (successive poses) is influenced by the maneuver permission, by the I2V messages and also by the intersection redesigned layout and presence of other vehicles. An increase in the traffic throughput with least dependency on infrastructure is achieved.
- SARS-CoV-2 e as crianças: que comunicação?Publication . Casimiro, Inês Alves; Eiró-Gomes, MafaldaA pandemia causada pelo vírus SARS-CoV-2 no início de 2020 trouxe desafios a vários níveis e na área da comunicação também. Durante meses a fio apenas se falava sobre a pandemia e tudo o que estivesse relacionado com ela. A comunicação em saúde passou a estar na ordem do dia, muito aliada à comunicação do risco e de crise. Essa comunicação, para um grande número de pessoas, reduzia-se, no entanto, à transmissão de conselhos de proteção e medidas de higiene. De alguns países começaram a surgir também algumas notícias sobre o modo como alguns governos e outras entidades públicas estavam a comunicar a pandemia a um público-alvo específico: as crianças. Daí surgiu este trabalho, iniciando-se com uma pesquisa exploratória de comunicação para a infância por vários países do mundo e, depois, afunilando-se para uma pesquisa de comunicações para crianças em Portugal. Durante o período de 1 de março a 30 de junho de 2020 foram encontrados apenas 18 resultados e esses resultados foram analisados nesta investigação através de uma análise de conteúdo com recurso a uma categorização temática elaborada a partir de referências bibliográficas e dos melhores exemplos de comunicação internacionais para crianças.
- On the performance of 5G for cloud- and edge-based emergency services in smart citiesPublication . Perna, Gonçalo; Rosmaninho, Rodrigo; Sampaio, Hugo; Rito, Pedro; Luís, Miguel; Sargento, SusanaThe deployment of emergency services in a city scenario, such as the ones for users’ safety in the roads, require the support of fast network technologies and efficient network architectures. Moreover, these services need to be available city-wide, so a flexible approach is needed to deploy high-speed technology to the overall city.This paper addresses the performance of 5G technology and its architecture to deploy emergency services with strict requirements, when compared to the use of fiber throughout the city. It considers the location of demanding services, in this specific case the people detection in the road through video cameras, both in the edge and the cloud, and with both fiber and real 5G connection between the edge and the cloud. We evaluate this architecture in a real scenario with real users and vehicles in the area. The obtained results show that 5G with an edge-based approach can provide similar services to fiber-based connections to the cloud.
- Film journalism: ways to build a definitionPublication . Lourenço, Jaime; Centeno, Maria JoãoFilm Journalism as a study object is still unexplored by social and communication sciences. It must be understood as a particular field of cultural journalism, assuming itself as a journalistic practice that focus on the cultural and artistic activity, that marked the 20th century and insists on following into the 21st century, the Cinema. Viewed as a subgenre of cultural journalism, Film Journalism assumes itself as an informative, critical, and pedagogical field. In the current article, in face of the scarcity of investigations about this topic in Portugal and based on semi-structured interviews to the main Portuguese journalists who daily dedicate themselves to the coverage of cinema, we seek to contribute towards the definition of Film Journalism as a journalistic practice insert in the scope of cultural journalism.