2020
Autores
Gouveia, J; Gouveia, C; Rodrigues, J; Carvalho, L; Moreira, CL; Lopes, JAP;
Publicação
ELECTRIC POWER SYSTEMS RESEARCH
Abstract
The integration of distributed Battery Energy Storage Systems (BESS) at the Medium Voltage (MV) and Low Voltage (LV) networks increases the distribution grid flexibility to deal with high penetration of Renewable Energy Sources (RES). In addition, it also enables the deployment of key self-healing functionalities, which allow the islanded operation of small sections of the distribution network. However, new planning and real-time operation strategies are required to allow the BESS coordinated control, as well as a cost-effective and stable operation. This paper presents new tools developed for the planning and real-time operation of distribution networks integrating BESS, particularly when operating islanding. For real-time operation, a short-term emergency operation-planning tool assesses the feasibility of islanded operation of a small section of the distribution network. The long-term impact of a BESS control strategy for islanded operation is assessed through a Life Cycle Analysis (LCA) tool. The results and implementation experience in real distribution network are also discussed.
2020
Autores
Pinto, JR; Cardoso, JS;
Publicação
2020 INTERNATIONAL CONFERENCE OF THE BIOMETRICS SPECIAL INTEREST GROUP (BIOSIG)
Abstract
The literature seems to indicate that the QRS complex is the most important component of the electrocardiogram (ECG) for biometrics. To verify this claim, we use interpretability tools to explain how a convolutional neural network uses ECG signals to identify people, using on-the-person (PTB) and off-the-person (UofTDB) signals. While the QRS complex appears indeed to be a key feature on ECG biometrics, especially with cleaner signals, results indicate that, for larger populations in off-the-person settings, the QRS shares relevance with other heartbeat components, which it is essential to locate. These insights indicate that avoiding excessive focus on the QRS complex, using decision explanations during training, could be useful for model regularisation.
2020
Autores
Rocha R.; Collado J.V.; Soares T.; Retorta F.;
Publicação
International Conference on the European Energy Market, EEM
Abstract
Renewable energy communities (REC) and local energy markets (LEM) emerge as entities capable, not only to promote the penetration of renewable energy sources into lower levels of the grid, but also to manage distributed energy resources (DER) and local energy exchanges between small players. This paper proposes a benefit assessment among different regulatory frameworks for LEM, considering network constraints and a virtual storage unit. Results show significant savings can be achieved, even without storage. Therefore, the continuous increase of DER can have considerable grid impacts if not complemented by other structures as storage or by alternative market services like flexibility.
2020
Autores
Loureiro, G; Dias, A; Martins, A;
Publicação
Robots in Human Life- Proceedings of the 23rd International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, CLAWAR 2020
Abstract
For the past years, the interest in the use of Unmanned Aerial Vehicles (UAVs) has been increasing due to the multiple research topics provided by the field of aerial robotics. Conversely, vehicles are susceptible to failures or malfunctions. Consequently, one main emergent research topic is the detection of a safe landing spot in these emergency scenarios. Therefore, this paper exposes and details the multiple techniques that attempt to solve the problem of landing site detection. This paper aims to present the current literature with several sensors that can be used to solve the aforementioned problem. Finally, the paper presents our proposed approach with some preliminary results in simulation. © CLAWAR Association Ltd.
2020
Autores
Zêdo, Y; Costa, J; Andrade, V; Au Yong Oliveira, M;
Publicação
Advances in Intelligent Systems and Computing
Abstract
This article was written to study and understand how social networks have changed the way we perceive and create relationships. The exponential increase of social media (SM) has become not only convenient, but also a common habit. It has changed people’s habits and brought a new way of being since the technology era arrived. Although there are several advantages in using these social networks, the uncontrolled use and abuse can be alarming, thus the importance of this research. There are plenty of papers related to the impact of social media on adolescent behaviour and on young people’s academic performance. However, this paper aims to examine the facts and provides a comparison of the effect of social media use between different age sectors: adolescents (between 10 and 17 years old), young adults (18–30), adults (31–45), older adults (46–65) and seniors (+66). In order to explore this issue, an online survey was developed. Using a sample of 358 participants, social media use was analysed by age sectors, focusing on the dependence, habits, the reasons/motivations for people to have these accounts, and how different generations perceive the future of social media. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2020.
2020
Autores
Sousa, RO; Martins, E; Carvalho, DN; Alves, AL; Oliveira, C; Duarte, ARC; Silva, TH; Reis, RL;
Publicação
JOURNAL OF POLYMER RESEARCH
Abstract
The extraction of collagen from fish skins is being proposed as strategy for valorization of marine origin by-products, being a sustainable alternative to mammal collagen. The method commonly uses solutions of organic acids, but new methodologies are arising, aiming to improve process yields and/or the properties of the resulting products. In this work, skins removed from salt brine Atlantic cod (Gadus morhua) were used to extract collagen, using water acidified with CO2, obtaining an extraction yield of 13.8% (w/w). Acidified water extracted collagen (AWC) presented a total content of proline-like amino acids of 151/1000 residues, with a degree of hydroxylation of 38%, and its SDS-PAGE profile is compatible with type I collagen. Moreover, FTIR, CD and XRD results suggest the presence of preserved triple helix, having a denaturation temperature of 32.3 degrees C as determined by micro-DSC. AWC exhibited a typical shear thinning behavior, interesting regarding their further processing, namely in jelly-like formulations. Additionally, the presence of AWC in MRC-5 human fibroblasts culture did not affect cell viability, demonstrating the non-cytotoxic behavior. Overall, the results support the efficiency of the proposed approach for collagen extraction and further enable the design of methodologies to address AWC use in biomedical or cosmetic context.
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