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Publications

2020

Video-assisted Overtaking System Enabled by C-V2X Mode 4 Communications

Authors
Magalhaes, P; D'Orey, PM; Andrade, MT; Castro, F;

Publication
2020 16TH INTERNATIONAL CONFERENCE ON WIRELESS AND MOBILE COMPUTING, NETWORKING AND COMMUNICATIONS (WIMOB)

Abstract
The overtaking maneuver can be often dangerous and risky, especially when driving in rural roads, with a significant probability of leading to fatalities and serious injuries. Vehicle communication emerges as one of the leading technologies to improve the driving experience and road safety. This article presents a system designed to augment road safety in an Overtaking Maneuver, providing the ahead vehicle's Line-of-Sight by real-time video-streaming. It uses the C-V2X Transmission Mode 4 that, building upon cellular technology, has evolved as one of the main standards for vehicle communication. Results show an effective application of the system in real overtaking scenarios, enhancing the safety and proving its usefulness. Whilst having some impact on the latency, the solution incurred in low packet losses and provided good video quality.

2020

Model Predictive Current Control of Switched Reluctance Motor Drive: An Initial Study

Authors
Pereira, M; Araújo, RE;

Publication
DoCEIS

Abstract
A considerable amount of research within the last few decades has been focusing on controllers for switched reluctance motor drives and how they affect the torque ripple. Despite all its potentials, there are still major concerns and obstacles to overcome concerning the dependency of the magnetic characteristic of the switched reluctance motor. This work targets these concerns by proposing an initial study of the fundamentals of a drive scheme using a finite set model predictive control for a switched reluctance motor through an asymmetric bridge converter. The implementation of this scheme is the main contribution of this paper. The method uses the dynamic model of the motor to estimate the future behavior of the current for each converter state. A cost function then evaluates which switching state minimizes the current error and applies it to the motor. Some simulation results illustrate the technique. Simulation results show the good performance of the method with fast and accurate transient response.

2020

Portuguese Project Management Profile—An Overview

Authors
Andrade Dias, A; Amaral, A;

Publication
Lecture Notes in Management and Industrial Engineering - Project Management and Engineering Research

Abstract

2020

Height Optimization in Aerial Networks for Enhanced Broadband Communications at Sea

Authors
Teixeira, FB; Campos, R; Ricardo, M;

Publication
IEEE ACCESS

Abstract
The Blue Economy has been growing in sectors such as offshore renewable energy, aquaculture, marine biotechnology, and deep sea mining. However, suitable wireless and mobile communications are lacking offshore. On the one hand, there is no coverage from terrestrial networks; on the other hand, satellite communications are still narrowband and expensive. Recently, the use of multi-hop airborne communications has been proposed to extend the coverage from terrestrial networks offshore but the communications range of these solutions is highly dependent on the height of the communications nodes. In this paper, we study the RF signal propagation in the maritime environment when the height of the receiver is changed and propose a position control approach for airborne multi-hop networks that maximizes the network capacity by taking full advantage of the signal reflections on the sea surface. The results obtained show that the proposed approach can provide lower propagation losses and higher network throughputs than random or fixed height approaches.

2020

Teaching Software Engineering Topics Through Pedagogical Game Design Patterns: An Empirical Study

Authors
Flores, N; Paiva, ACR; Cruz, N;

Publication
INFORMATION

Abstract
Teaching software engineering in its many different forms using traditional teaching methods is difficult. Serious games can help overcome these challenges because they allow real situations to be simulated. However, the development of serious games is not easy and, although there are good practices for relating game design patterns to teaching techniques, there is no methodology to support its use in a specific context such as software engineering. This article presents a case study to validate a methodology that links the Learning and Teaching Functions (LTF) to the Game Design Patterns (PIB) in the context of Software Engineering Education. A serious game was developed from scratch using this methodology to teach software estimation (a specific topic of software engineering). An experiment was carried out to validate the effectiveness of the game by comparing the results of two different groups of students. The results indicate that the methodology can help to develop effective educational games on specific learning topics.

2020

A Fuzzy Modal Logic for Fuzzy Transition Systems

Authors
Jain, M; Madeira, A; Martins, MA;

Publication
ELECTRONIC NOTES IN THEORETICAL COMPUTER SCIENCE

Abstract
This paper intends to contribute with a new fuzzy modal logic to model and reason about transition systems involving uncertainty in behaviours. Our formalism supports fuzziness at transitions and on the proposition symbols assignment levels. Against of other approaches in the literature, our bisimulation and bisimilarity notions generalise the analogous standard notions of classic modal logic and of process algebras. Moreover, the outcome of our logic is also fuzzy, with the semantic interpretation of connectives supported by the Godel algebra.

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