Cookies
O website necessita de alguns cookies e outros recursos semelhantes para funcionar. Caso o permita, o INESC TEC irá utilizar cookies para recolher dados sobre as suas visitas, contribuindo, assim, para estatísticas agregadas que permitem melhorar o nosso serviço. Ver mais
Aceitar Rejeitar
  • Menu
Publicações

2020

Modelling and simulation of electromagnetically induced transparency in hollow-core microstructured optical fibres

Autores
Rodrigues, SMG; Facao, M; Ines Carvalho, MI; Ferreira, MFS;

Publicação
OPTICS COMMUNICATIONS

Abstract
We study the electromagnetically induced transparency (EIT) phenomenon in a hollow-core fibre filled with rubidium gas. We analyse the impact of the guiding effect and of the temperature on the properties of the EIT phenomenon. The refractive index felt by the probe laser is found to vary due to the radial dependence of the fibre mode field at the pump frequency. Several results are presented for the transmission, dispersion, and group velocity of the probe field, considering both the free propagation regime and the guided propagation along the hollow-core fibre. We note that the EIT occurring in a waveguide has a great potential for practical applications since it can be controlled by adjusting the gas and the fibre properties.

2020

Gastric Microbiome Diversities in Gastric Cancer Patients from Europe and Asia Mimic the Human Population Structure and Are Partly Driven by Microbiome Quantitative Trait Loci

Autores
Cavadas, B; Camacho, R; Ferreira, JC; Ferreira, RM; Figueiredo, C; Brazma, A; Fonseca, NA; Pereira, L;

Publicação
MICROORGANISMS

Abstract
The human gastrointestinal tract harbors approximately 100 trillion microorganisms with different microbial compositions across geographic locations. In this work, we used RNASeq data from stomach samples of non-disease (164 individuals from European ancestry) and gastric cancer patients (137 from Europe and Asia) from public databases. Although these data were intended to characterize the human expression profiles, they allowed for a reliable inference of the microbiome composition, as confirmed from measures such as the genus coverage, richness and evenness. The microbiome diversity (weighted UniFrac distances) in gastric cancer mimics host diversity across the world, with European gastric microbiome profiles clustering together, distinct from Asian ones. Despite the confirmed loss of microbiome diversity from a healthy status to a cancer status, the structured profile was still recognized in the disease condition. In concordance with the parallel host-bacteria population structure, we found 16 human loci (non-synonymous variants) in the European-descendent cohorts that were significantly associated with specific genera abundance. These microbiome quantitative trait loci display heterogeneity between population groups, being mainly linked to the immune system or cellular features that may play a role in enabling microbe colonization and inflammation.

2020

Audiovisual Classification of Group Emotion Valence Using Activity Recognition Networks

Autores
Pinto, JR; Gonçalves, T; Pinto, C; Sanhudo, L; Fonseca, J; Gonçalves, F; Carvalho, P; Cardoso, JS;

Publicação
4th IEEE International Conference on Image Processing, Applications and Systems, IPAS 2020, Virtual Event, Italy, December 9-11, 2020

Abstract
Despite recent efforts, accuracy in group emotion recognition is still generally low. One of the reasons for these underwhelming performance levels is the scarcity of available labeled data which, like the literature approaches, is mainly focused on still images. In this work, we address this problem by adapting an inflated ResNet-50 pretrained for a similar task, activity recognition, where large labeled video datasets are available. Audio information is processed using a Bidirectional Long Short-Term Memory (Bi-LSTM) network receiving extracted features. A multimodal approach fuses audio and video information at the score level using a support vector machine classifier. Evaluation with data from the EmotiW 2020 AV Group-Level Emotion sub-challenge shows a final test accuracy of 65.74% for the multimodal approach, approximately 18% higher than the official baseline. The results show that using activity recognition pretraining offers performance advantages for group-emotion recognition and that audio is essential to improve the accuracy and robustness of video-based recognition. © 2020 IEEE.

2020

Multi-label Stream Classification with Self-Organizing Maps

Autores
Cerri, R; Costa Júnior, JD; Faria Paiva, ERd; da Gama, JMP;

Publicação
CoRR

Abstract

2020

Smart load scheduling strategy utilising optimal charging of electric vehicles in power grids based on an optimisation algorithm

Autores
Lu, M; Abedinia, O; Bagheri, M; Ghadimi, N; Shafie khah, M; Catalao, JPS;

Publicação
IET SMART GRID

Abstract
One of the main goals of any power grid is sustainability. The given study proposes a new method, which aims to reduce users' anxiety especially at slow charging stations and improve the smart charging model to increase the benefits for the electric vehicles' owners, which in turn will increase the grid stability. The issue under consideration is modelled as an optimisation problem to minimise the cost of charging. This approach levels the load effectively throughout the day by providing power to charge EVs' batteries during the off-peak hours and drawing it from the EVs' batteries during peak-demand hours of the day. In order to minimise the costs associated with EVs' charging in the given optimisation problem, an improved version of an intelligent algorithm is developed. In order to evaluate the effectiveness of the proposed technique, it is implemented on several standard models with various loads, as well as compared with other optimisation methods. The superiority and efficiency of the proposed method are demonstrated, by analysing the obtained results and comparing them with the ones produced by the competitor techniques.

2020

Critical Success Factors in a Six Dimensional Model CRM Strategy

Autores
Santos, JD; Castelo, JP; Almeida, F;

Publicação
Encyclopedia of Organizational Knowledge, Administration, and Technology

Abstract
[No abstract available]

  • 1297
  • 4180