Resultados da pesquisa
Catálogo de Publicações - Todos
- A mostrar 1 - 10 resultados de 916
- Go to Next Page
-
1
Multicarrier Waveform Candidates for Beyond 5G
Publicaçãopor khan, BahramOutros Autores: Velez, Fernando J.Origem: uBibliorumTo fulfil the requirements of 5G vision of “everything everywhere and always connected”, a new waveform must contain the features to support a greater number of users on high data rate. Although Orthogonal Frequency Division Multiplexing (OFDM) has been widely used in the 4th generation, but it can hardly meet the needs of 5G vision. However, many waveforms have been proposed to cope with new challenges. In this paper, we have presented a comparative analysis of several waveform candidates (FBMC, GFDM, UFMC, F-OFDM) on the basis of complexity, hardware design and other valuable characteristics. Filter based waveforms have much better Out of Band Emission (OoBE) as compared to OFDM. However, F-OFDM has smaller filter length compared to filter-based waveforms and provides better transmission with multiple antenna system without any extra processing, while providing flexible frequency multiplexing, shorter latency and relaxed synchronization as compared to other waveforms. -
2
Second- order differential equations in the Laguerre-Hahn class
Publicaçãopor Rebocho, Maria das NevesOutros Autores: Branquinho, A.; Paiva, Anabela; Foulquie-Moreno, AnaOrigem: uBibliorumLaguerre-Hahn families on the real line are characterized in terms of second order differential equations with matrix coefficients for vectors involving the orthogonal polynomials and their associated polynomials, as well as in terms of second order differential equation for the functions of the second kind. Some characterizations of the classical families are derived. -
3
Symmetric semi-classical orthogonal polynomials of class one on q-quadratic lattices
Publicaçãopor Rebocho, M. N.Outros Autores: Filipuk, GalinaOrigem: uBibliorumIn this paper we study discrete semi-classical orthogonal polynomials on non-uniform lattices. In the symmetric class one case we give a closed form expression for the recurrence coefficients of orthogonal polynomials. -
4
Stacked Denoising Autoencoders and Transfer Learning for Immunogold Particles Detection and Recognition
Publicaçãopor Sousa, RicardoOutros Autores: Santos, Jorge M.; Silva, Luís M.; Alexandre, Luís; Esteves, Tiago; Rocha, Sara et al.Origem: uBibliorumIn this paper we present a system for the detection of immunogold particles and a Transfer Learning (TL) framework for the recognition of these immunogold particles. Immunogold particles are part of a high-magnification method for the selective localization of biological molecules at the subcellular level only visible through Electron Microscopy. The number of immunogold particles in the cell walls allows the assessment of the differences in their compositions providing a tool to analise the quality of different plants. For its quantization one requires a laborious manual labeling (or annotation) of images containing hundreds of particles. The system that is proposed in this paper can leverage significantly the burden of this manual task. For particle detection we use a LoG filter coupled with a SDA. In order to improve the recognition, we also study the applicability of TL settings for immunogold recognition. TL reuses the learning model of a source problem on other datasets (target problems) containing particles of different sizes. The proposed system was developed to solve a particular problem on maize cells, namely to determine the composition of cell wall ingrowths in endosperm transfer cells. This novel dataset as well as the code for reproducing our experiments is made publicly available. We determined that the LoG detector alone attained more than 84\% of accuracy with the F-measure. Developing immunogold recognition with TL also provided superior performance when compared with the baseline models augmenting the accuracy rates by 10\%. -
5
On differential equations for orthogonal polynomials on the unit circle
Publicaçãopor Branquinho, A.Outros Autores: Rebocho, M. N.Origem: uBibliorumIn this paper we characterize sequences of orthogonal polynomials on the unit circle whose corresponding Carathéodory function satisfies a Riccati differential equation with polynomial coefficients, in terms of second order matrix differential equations. -
6
A characterization theorem for semi-classical orthogonal polynomials on non-uniform lattices
Publicaçãopor Rebocho, M. N.Outros Autores: Filipuk, Galina; Chen, Yang; Branquinho, A.Origem: uBibliorumIt is proved a characterization theorem for semi-classical orthogonal polynomials on non- uniform lattices that states the equivalence between the Pearson equation for the weight and some systems involving the orthogonal polynomials as well as the functions of the second kind. As a consequence, it is deduced the analogue of the so-called compatibility conditions in the ladder operator scheme. The classical orthogonal polynomials on non- uniform lattices are then recovered under such compatibility conditions, through a closed formula for the recurrence relation coefficients. -
7
Distributional equation for Laguerre- Hahn functionals on the unit circle
Publicaçãopor Branquinho, A.Outros Autores: Rebocho, M. N.Origem: uBibliorumLet u be a hermitian linear functional defined in the linear space of Laurent polynomials and F its corresponding Carathéodory function. [...] -
8
Distribution-Based Categorization of Classifier Transfer Learning
Publicaçãopor Sousa, Ricardo GamelasOutros Autores: Alexandre, Luís; Santos, Jorge M.; Silva, Luís M.; Sá, Joaquim Marques deOrigem: uBibliorumTransfer Learning (TL) aims to transfer knowledge acquired in one problem, the source problem, onto another problem, the target problem, dispensing with the bottom-up construction of the target model. Due to its relevance, TL has gained significant interest in the Machine Learning community since it paves the way to devise intelligent learning models that can easily be tailored to many different applications. As it is natural in a fast evolving area, a wide variety of TL methods, settings and nomenclature have been proposed so far. However, a wide range of works have been reporting different names for the same concepts. This concept and terminology mixture contribute however to obscure the TL field, hindering its proper consideration. In this paper we present a review of the literature on the majority of classification TL methods, and also a distribution-based categorization of TL with a common nomenclature suitable to classification problems. Under this perspective three main TL categories are presented, discussed and illustrated with examples. -
9
Reference Scenarios and Key Performance Indicators for 5G Ultra-dense Networks
Publicaçãopor Campos, Luís MiguelOutros Autores: Ribeiro, Luís; Karydis, Ioannis; Karagiannis, Stelios; Pedro, Dário; Martins, Jorge et al.Origem: uBibliorumThe so-called 5G will revolutionize the way we live, and work. In order to demonstrate the profound changes, we can expect to experience within the next 5 to 10 years, we present use cases for the planned research within the TeamUp5G project. Some use cases are strongly linked to the network layer and aim at developing solutions capable of optimizing the main promising benefits of 5G: extremely low latency and extremely high bandwidth (e.g., handle video streams, traffic congestion, user profiles), in the most efficient way possible. Other use cases focus on commercial applications that make use of middleware applications to enhance their performance. The latter fall into two main areas: real-time virtual reality and live video streaming, which are extremely demanding in terms of latency and bandwidth to provide an acceptable QoE/QoS to multiple users. The use cases presented are built assuming that 5G is essential for their support with appropriate QoE/QoS. Key performance indicators and their range of variation are also identified. -
10
Deployment of Beyond 4G Wireless Communication Networks with Carrier Aggregation
Publicaçãopor Khan, BahramOutros Autores: Velez, Fernando J.Origem: uBibliorumWith the growing demand for new blend of applications, the user’s dependency on the Internet is increasing day by day. Mobile Internet users are giving more attention to their own experience, especially in terms of communication reliability, high data rate and service stability on the move. This increase in the demand is causing saturation of existing radio frequency bands. To address these challenges, many researchers are finding the best approach, Carrier Aggregation (CA) is one of the newest innovations which seems to fulfil the demands of future spectrum, CA is one the most important feature for Long Term Evolution - Advanced. In direction to get the upcoming International Mobile Telecommunication Advanced (IMT-Advanced) mobile requirements 1 Gb/s peak data rate, the CA scheme is presented by 3GPP to sustain high data rate using widespread frequency bandwidth up to 100 MHz. Technical issues containing the aggregation structure, its implementation, deployment scenarios, control signal technique and challenges for CA technique in LTE-Advanced, with consideration backward compatibility are highlighted. Performance evaluation in macrocellular scenarios through a simulation approach shows the benefits of applying CA and low-complexity multi-band schedulers in service quality and system capacity enhancement. The Enhanced multi-band scheduler is less complex than the General multi-band scheduler and performs better for cell radius longer than 1800 m (and a PLR threshold of 2%).
Ferramentas de pesquisa:
Filtros
Page will reload when a filter is selected or excluded.- Branquinho, A. 23 results 23
- Novoa, Antonio 23 results 23
- Rebocho, M. N. 23 results 23
- Urbano, José Miguel 23 results 23
- Oliveira, Paulo Eduardo 16 results 16
- Ferreira, J. A. 13 results 13
- Picado, Jorge 13 results 13
- Abreu, Luís Daniel 12 results 12
- Mamede, Ricardo 12 results 12
- Sobral, Manuela 12 results 12
- Azenhas, Olga 10 results 10
- Costa, J. M. Nunes da 10 results 10
- Figueiredo, Isabel N. 10 results 10
- Pintado, Manuela 9 results 9
- Vicente, Luís Nunes 9 results 9
- Duxbury, Nancy 8 results 8
- Filipuk, Galina 8 results 8
- Leite, F. Silva 8 results 8
- Sousa, Ercília 8 results 8
- Vicente, L. N. 8 results 8
- Chinita, Fátima 7 results 7
- Araújo, A. 6 results 6
- Carvalho, F. J. Craveiro de 6 results 6
- Clementino, Maria Manuel 6 results 6
- Dias, Oscar 6 results 6
- Guerra, Telma 6 results 6
- Janelidze, George 6 results 6
- Lencastre, José Alberto 6 results 6
- Matoso, Rui 6 results 6
- Rocha, Miguel 6 results 6
- Ver todos...
- Portugal 18 results 18
- Orthogonal polynomials 16 results 16
- Stability 15 results 15
- Optimal control 9 results 9
- Derivative-free optimization 8 results 8
- Finite differences 8 results 8
- Frame 8 results 8
- Measures on the unit circle 8 results 8
- Semi-classical functionals 8 results 8
- Artificial intelligence 7 results 7
- Carathéodory function 7 results 7
- Educação 7 results 7
- Ciências Sociais::Ciências da Educação 6 results 6
- Direct search 6 results 6
- Intrinsic scaling 6 results 6
- Professores 6 results 6
- Semi-abelian category 6 results 6
- Association 5 results 5
- COVID-19 5 results 5
- Engenharia e Tecnologia::Engenharia Civil 5 results 5
- Hermitian functionals 5 results 5
- Lie algebroids 5 results 5
- Numerical range 5 results 5
- Optimization 5 results 5
- Orthogonal polynomials on the unit circle 5 results 5
- Recurrence relations 5 results 5
- Stieltjes function 5 results 5
- Tax law 5 results 5
- Time series 5 results 5
- Categorical Galois theory 4 results 4
- Ver todos...
- Estudo Geral - Universidade de Coimbra 394 results 394
- Veritati - Repositório Institucional da Universidade Católica Portuguesa 159 results 159
- Repositório da Universidade de Lisboa 77 results 77
- RepositóriUM - Universidade do Minho 60 results 60
- Repositório Científico da Universidade Politécnica de Lisboa 40 results 40
- Universidade Politécnica de Setúbal 34 results 34
- RIA - Repositório Institucional da Universidade de Aveiro 25 results 25
- Repositório Científico do Instituto Politécnico do Porto 20 results 20
- Repositório Aberto da Universidade Aberta 11 results 11
- Repositório Científico da Universidade Politécnica de Castelo Branco 10 results 10
- Repositório Científico da Universidade Politécnica de Viseu 7 results 7
- ARCA 5 results 5
- Sapientia - Universidade do Algarve 5 results 5
- Repositório Institucional da Fernando Pessoa 4 results 4
- IC-online 3 results 3
- Repositório Científico IPVC 3 results 3
- Repositório da UTAD 3 results 3
- Repositório Institucional da UNL 2 results 2
- Repositório da Universidade Portucalense 2 results 2
- Repositório da Universidade dos Açores 2 results 2
- Camões - Repositório Institucional da Universidade Autónoma de Lisboa 1 results 1
- Campo Arqueológico de Mértola 1 results 1
- Casa de Camilo 1 results 1
- DigitUMa - Repositório da Universidade da Madeira 1 results 1
- Escola Superior de Saúde Norte da Cruz Vermelha Portuguesa 1 results 1
- Escola Superior de Saúde do Alcoitão 1 results 1
- Repositório de Dados Científicos 1 results 1
- Repositório do Hospital Prof. Doutor Fernando Fonseca 1 results 1
- Repositório Institucional do IPBeja 1 results 1
- Repositório Aberto do Instituto Superior Miguel Torga 1 results 1
- Ver todos...
- Universidade de Coimbra 394 results 394
- Universidade Católica Portuguesa 159 results 159
- Universidade de Lisboa 77 results 77
- Universidade do Minho 60 results 60
- Universidade Politécnica de Lisboa 40 results 40
- Universidade Politécnica de Setúbal 34 results 34
- Universidade de Aveiro 25 results 25
- Instituto Politécnico do Porto 20 results 20
- Universidade Aberta 11 results 11
- Universidade Politécnica de Castelo Branco 10 results 10
- Universidade Politécnica de Viseu 7 results 7
- Repositório do GIMM – Gulbenkian Institute for Molecular Medicine 5 results 5
- Universidade do Algarve 5 results 5
- Universidade Fernando Pessoa 4 results 4
- Instituto Politécnico de Viana do Castelo 3 results 3
- Universidade de Leiria e Oeste 3 results 3
- Universidade de Trás-os-Montes e Alto Douro 3 results 3
- Universidade dos Açores 2 results 2
- Universidade Nova de Lisboa 2 results 2
- Universidade Portucalense 2 results 2
- Campo Arqueológico de Mértola 1 results 1
- Casa de Camilo 1 results 1
- RCAAP 1 results 1
- Universidade da Madeira 1 results 1
- Escola Superior de Saúde Norte da Cruz Vermelha Portuguesa 1 results 1
- Escola Superior de Saúde do Alcoitão 1 results 1
- Hospital Prof. Dr. Fernando Fonseca E.P.E. 1 results 1
- Instituto Politécnico de Beja 1 results 1
- Instituto Superior Miguel Torga 1 results 1
- Serviço de Saúde da Região Autónoma da Madeira, E.P.E. 1 results 1
- Ver todos...
- 5876 10 results 10
- 6817 - DCRRNI ID 9 results 9
- SFRH 9 results 9
- H2020 7 results 7
- Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017/2018) - Financiamento Base 3 results 3
- 3599-PPCDT 2 results 2
- Avaliação UID 2023/2024 2 results 2
- CEEC IND 2018 2 results 2
- 5665-PICT 1 results 1
- 6820 - DCRRNI ID 1 results 1
- Bolsa de Doutoramento 1 results 1
- COMPETE 1 results 1
- Concurso para Atribuição do Estatuto e Financiamento de Laboratórios Associados (LA) 1 results 1
- Concurso para Financiamento de Projetos de Investigação Científica e Desenvolvimento Tecnológico em Todos os Domínios Científicos - 2017 1 results 1
- Concurso para Financiamento de Projetos de Investigação Científica e Desenvolvimento Tecnológico em Todos os Domínios Científicos - 2020 1 results 1
- FP7 1 results 1
- HE 1 results 1
- Immune System in Health and Disease 1 results 1
- MRC 1 results 1
- Nanosciences, Nanotechnologies, Materials and new Production Technologies - NMP 1 results 1
- Research Potential 1 results 1
- Ver todos...