Biblioteca Digital do IPB
Repositório de Publicações do Instituto Politécnico de Bragança
Entradas recentes
Advance Reconnaissance of UGV Path Planning Using Unmanned Aerial Vehicle to Carry Our Mission in Unknown Environment
Publication . Nowakowski, Marek; Berger, Guido S.; Braun, João A.; Mendes, João; Bonzatto Junior, Luciano; Lima, José
The utilization of unmanned vehicles for specialized tasks has gained significant attention in both military and civilian domains. This article explores the application of commercial unmanned aerial vehicles (UAVs) for reconnaissance purposes, specifically to verify autonomous driving missions assigned to the developed TAERO manned-unmanned vehicle in field operations. The paper introduces the TAERO vehicle, highlighting its functionality and capabilities for unmanned missions. The architecture of the unmanned ground vehicle (UGV) system is discussed taking into consideration the autonomy subsystem and used location data. The limitations associated with terrain and potential obstacles are addressed as well as importance of acquiring accurate terrain information for successful autonomous operation. The solution proposed in our study involves the use of a commercially available UAV applied to the visual tracking of potential targets in an engagement scenario. Details related to flight route planning system, geolocation, target tracking, and data transmission between robotic platforms are discussed and presented in this work. The acquired real-time data plays a crucial role in confirming the mission, making necessary adjustments, or altering the planned route. The UAV platform, known for its maneuverability and operational capabilities, can operate ahead as a reconnaissance element, improving the overall reconnaissance capabilities of the system. Upon completion of the mission, the UAV can return to the base or land on a moving vehicle platform. The authors proposed integration of a UAV that significantly enhances the autonomous mode capabilities of unmanned ground platform, improving operation in unknown environment during special mission.
2024 U.S. presidential elections: An event study for U.S. and non-U.S. fossil fuel and renewable listed firms
Publication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno
This study examines the short-term market effect of Donald Trump' victory in the 2024 US presidential election on largest US and non-US listed worldwide fuel fossil and renewable firms. Employing an event study methodology, we observe a negative and statistically significant stock price reaction for worldwide renewable listed firms. An analysis by economic zones reveals the existence of negative abnormal returns for renewable energy firms in the US, Europe, India and in the rest of the world. In the case of China, abnormal returns are not statistically significant. With respect to worldwide fossil fuel listed firms, abnormal returns are generally not statistically significant. However, regarding US firms, we observe positive and statistically significant abnormal returns. These abnormal returns are explained by the change of US energy policy (pro-oil and gas policy) and the expected cut in subsidies and lower profitability of investments in green energies. Finally, our study provide insight into which firm-specific characteristics emerge as value drives around US presidential elections. The results show that despite the change in environmental policy in the US, favourable to fossil energy, the stock markets reward firms with high environmental ratings. Overall, our results indicate that 2024 US presidential election, for implying a change in US energy policy, has relevant policy implications for energy listed firms.
Laser Engraving for 3D Surfaces: A Robotized Application Case Study
Publication . Alvarez, Mariano José; Brancalião, Laiany Suganuma; Carneiro, Jorge; Costa, Paulo; Coelho, João Paulo; Gonçalves, José
One of the industry’s most common applications of lasers is engraving, which is generally performed on flat surfaces. However, there are many situations where the object to be engraved has an unevenly curved geometry. In those cases, the light power density will be different along the surface for a fixed head, leading to a poor engraving result. This work deals with this problem by designing a robotic application capable of detecting variations on the object surface and automatically creating a trajectory to engrave on it correctly. This was made possible through a robotic manipulator, a time-of-flight distance sensor, and a data processing algorithm over the measured data. Obtained results were acquired using a custom-made test rig and validated by delivering consistent engraving results on irregular surface shapes.
SEO in Rural Tourism: A Case Study of Terras de Trás-os-Montes, Portugal
Publication . Morais, Elisabete Paulo; Esteves, Elsa Tavares; Cunha, Carlos R.
This research investigates the application of search engine optimization (SEO) in developing the digital image of rural tourism businesses in the Terras de Trás-os-Montes region of Portugal. With digital marketing becoming increasingly important for businesses to stay competitive, SEO has become a vital tool for developing online recognition, qualified traffic acquisition, and enhancement of conversion rates. The research performs an SEO analysis of 21 rural tourism websites by applying the Ubersuggest tool, analyzing such key indicators as on-page SEO scores, organic traffic, keyword ranking, backlinks, and technical performance. The results identify wide SEO performance discrepancies, with some sites registering excellent practices and others with critical errors that impair the sites' online recognizability. In particular, low word count, absent meta description, and loading speed issues are very much present. The research emphasizes the need for effective SEO methods, such as on-page maintenance, content creation, and link building, to advance search engine ranking and end-user experience. Moreover, the study emphasizes the necessity for rural tourism businesses to evolve and adapt to current SEO trends, i.e., voice search optimization and local SEO, in the changing digital business environment. The results provide recommendations for rural tourism businesses to develop their digital marketing activities and make progress online.
Fuzzy c-Means as a Decision Support Tool for Liver Disease Diagnosis Based on Data Analysis
Publication . Leite, Gabriel A.; Azevedo, Beatriz Flamia; Ferreira, Sofia Ribeiro; Pacheco, Maria F.; Fernandes, Florbela P.; Pereira, Ana I.
The liver is a vital organ responsible for numerous essential functions in the body. Thus, liver disorders can have severe consequences on overall health and well-being. Early diagnosis and treatment of liver disorders are crucial to prevent complications such as cirrhosis, liver failure and liver cancer. In this work, a data analysis system aims to identify the most important features in defining liver disease and categorize sick patients according to the severity of the disease. The Indian Liver Patient Dataset was evaluated using a pre-processing data analysis method that considered the Z-score, the correlation, and the Recursive Feature Elimination. After identifying the most important characteristics of the patients, the Fuzzy c-means algorithm was used to classify them based on the severity of the disease. The results of the proposed methodology proved to be effective in creating a decision support system, since it was possible to identify four levels of severity among the patients.