Search Results
Publication Catalog - All
- Showing 1 - 10 results of 1,519,678
- Go to Next Page
-
1
The Interface and Control System of the Upgraded HVOpto/HVRemote Card of the TileCal
Publicationby Augusto, José SoaresOther Authors: Rato, C.; Gurriana, L.; Seabra, L.; Gomes, A.; Evans, Guiomar et al.To comply with the increase in luminosity of the LHC (Large Hadron Collider) in the next decades, the electronics of the ATLAS (A Toroidal LHC Apparatus) experiment is being upgraded. Included in the upgrade is the interfacing and control electronics system of the HVOpto/HVRemote cards in the TileCal (Tile Calorimeter) detector, which provides high voltages to about 104 photomultipliers (PMTs). This paper presents the new interfacing architecture for the system and details the design of a prototype control board (HVRemote-Ctrl) used for test and validation of the new architecture. The tests evaluate the system multiplexing capabilities needed to monitor all the TileCal PMTs in real time. The communication channels involved, supported in Ethernet and SPI interfaces/protocols, have been fully tested. Some results from the tests already completed are presented. -
2
DEMUX OPERATION IN TANDEM AMORPHOUS SI-C DEVICES A two stage active circuit
Publicationby Vieira, Manuel AugustoOther Authors: Vieira, Manuela; Louro, Paula; Fantoni, Alessandro; Garção, Adolfo SteigerCharacteristics of tunable wavelength filters based on a-SiC:H multilayered stacked cells are studied both theoretically and experimentally. Curves of gain vs. wavelength illustrate the optical filter characteristics. A capacitive active band-pass filter model supports experimental data. Results show that the use of a double pi’n/pin a-SiC:H heterostructure as active capacitive filters depends on the wavelength and modulated frequency of the trigger light and on the wavelength of the additional optical bias. The devices combine three indispensable functions of transceivers, amplification, detection and wavelength filtering. Experimental and simulated results show the device combines the properties of active short-pass and long-pass filter sections into a capacitive active band-pass filter. -
3
A primer on understanding Google Earth Engine APIs
Publicationby Reis, RuiOther Authors: Datia, Nuno; Pato, MatildeThis article is build on the experience of using Google Earth Engine as a development framework for a previous work by the same authors.Being primarily a distributed parallel computing platform, it is designed around a functional language pattern, even though supported on an object model, and a map / reduce distributed workload paradigm.Leveraging the sheer computing power delivered by the Google infrastructure and a multi petabyte remote sensing data repository, GoogleEarth Engine is an efficient development framework that presents itself in two basic flavors: one online integrated development environment which uses the browser Javascript engine; two APIs that can be deployed to a Python or a NodeJS environment.This work emphasizes the comparison between the Javascript browserbased implementation and the Python environment packages. -
4
Social Mobility Advisor
Publicationby Costa, AndréOther Authors: Antunes, David; Filipe, Porfírio PenaSeamless access to updated information about mobility options is a key factor for sustainable economic development. In this context, the adoption of information systems, with innovative features, meet these needs by stimulating the interest and curiosity of end users. There are well known difficulties, even for regular travelers, to get the most suitable mobility options combining available transport modes. Also, the sustainable mobility has become the new imperative for transport policy. In this paper we present a collaborative platform that supports a Social Network, in which users can search and share sustainable mobility experiences. This platform includes a reputation and a recommender systems specially designed to deal with mobility options. -
5
Passive Optical Communications Module for the Internet of Things
Publicationby Ribeiro, TiagoThe Internet of Things (IoT) promotes interconnectivity between devices and these keep appearing in larger quantities throughout the years, with the evolution of communication technologies. However, scalability comes with a price, since for a higher quantity of devices comes the need for better transmission channels, with higher reach, availability and improved security capabilities. The infrastructure that comes with this ubiquitous network is very expensive so there is a need for finding low-cost solutions for the transmission of data, benefiting from the qualities of the optical fibers.Wireless technologies already provide a way to solve these issues, but the use of optical fibers would give to the IoT their own unique features, such as high bandwidth, long reach, signal integrity and high security. But IoT devices should not be power hungry nor have very limiting electrical-to-optical conversions, so a passive optical communications module based of fiber Bragg gratings for long reach and for the upload of information with low data rates should be implemented. This module would be integrated in the IoT ecosystem by connecting it to the existent dark fibers all over the world.A simulator of this module was implemented, capable of reproducing its characteristics for the transmission of information modulated in Frequency-Shift Keying and On-Off Keying modulation schemes. The study of the system performance for these schemes was made by estimating the Bit Error Rate using the Error Vector Magnitude metric, in relation to the received optical power. -
6
Optimal Control of a Multi-field Irrigation Problem: validation of a numerical solution by the optimality conditions
Publicationby Lopes, Sofia O.Other Authors: Fontes, Fernando A. C. C.In this paper, we address the problem of minimizing the total water consumption over the period of a year used to supply different fields with different types of crops.We start by recalling a previous study, where the authors developed an optimal control model for this problem by minimizing the water flowing into a reservoir and where the water from the precipitation can be collected. The numerical solution obtained using such model is analyzed.The main result in this paper is the theoretical validation of the numerical solution via a verifications that such solution satisfies the necessary conditions of optimality in the form of a Maximum Principle. This way, we are giving further evidence of the optimality of the numerical solution found. -
7
Project Wireless Sensor Network Architecture for Tunnel Monitoring
Publicationby Garay, JorgeOther Authors: Guimaraes, Felipe; De Oliveira, Alexandre; Kofuji, Sergio; Matta, FernandoAbstract: This paper presents an architecture for wireless sensor networks (WSN) operating in the 2.4GHz RF band for implementation in environments of small tunnels. The study begins with an objective description of the RF architecture and with the implementation of a RSSI analysis in real scenarios. The designed modules are using directional and omnidirectional antennas for each test scenario. In initial experiment is included a test on the 433Mhz band. The developed WSN architecture provides a higher degree of reliability at environments with denser structures (tunnels) and enables the use of directional and omnidirectional antennas for better signal behavior considering the structure of environment to propagation. -
8
Simulation of plasmonic effects of Metal (Au,Ag and Al) NPs and rGO embedded in aqueous solutions
Publicationby Stojkovic, VladanOther Authors: Louro, PaulaGraphene [1] is a material that has been extensively explored in recent years as a material with optical properties that enable its application as active material in sensing devices.In this work we will study plasmonic effects and optical properties of graphene and metal nanoparticles (AuNPs), comparing its results, whenever possible, with results obtained in previous studies. Analysis will be supported by simulation results obtained with Matlab (“Mie analysis”). -
9
MOBILEWHEEL A mobile driving station
Publicationby Cunha, VitorOther Authors: Campos, CarlosCurrent mobile devices (e.g., smartphones) are equipped with several sensors that allow different forms of userinteraction. They also offer several connectivity options and a growing computing power which supports itsuse in new Human Computer Interaction (HCI) scenarios. This paper presents the mobileWheel, a system thatexploits the capabilities of current mobile devices as a means of interaction with a real-time graphical drivingsimulation running on a desktop computer. The application on the mobile device performs data acquisitionfrom various sensors (focusing on the 3D accelerometer) and also provides different types of feedback tothe user. This system represents a ubiquitous, simple and affordable alternative approach to the traditionalcontrol of virtual vehicles in driving simulators and could also be applied in other similar architectures. Toevaluate and validate this approach several tests were conducted with volunteer users. The control mode wherethe virtual vehicle is fully controlled by the accelerometer had the highest acceptance and produced the bestresults. -
10
VLC system for the determination of a vehicle’s position and speed
Publicationby Rodrigues, FábioOther Authors: Vieira, Manuela; Louro, PaulaIn recent years, lighting solutions have gradually been replaced by more efficient features, taking advantage of Light Emitting Diodes (LEDs) that have progressively conquered the market with increasingly high optical powers, low energy consumption and variable color temperatures. Along with this evolution, Visible Light Communication (VLC) technology has also been developed to use this existing lighting infrastructure and the inherent characteristic of LEDs being easily switched to high frequency to build data transmission systems. The applications of this communication technology using electromagnetic signals in the visible range are currently in a development stage with promising applications in several domains.This paper intends to study an optical communication system based on VLC to establish communication between road infrastructures and. vehicles. For this purpose, four communication channels established through the modulation of white trichromatic LED emitters are used. Detection of the optical signals is performed with a photodiode based on two stacked pin structures made of a-Si:H and a-SiC:H. This device works as an optical filter in the visible spectrum and its spectral sensitivity can be adjusted through stationary optical bias. On-Off-Keying (OOK) modulation is used. The structure of the data blocks to be transmitted was designed to avoid undesirable effects related to ambient light (flickering and/or perceptible variations in color temperature of the white light). The experimental tests of the proposed model were performed using a small-scale prototype. The results show that with the proposed system it is possible to transmit information between road infrastructure and vehicles.
Search Tools:
Refine Results
Page will reload when a filter is selected or excluded.- Castro, Nuno Filipe 2,081 results 2,081
- ATLAS Collaboration 1,947 results 1,947
- Adams, T. 1,537 results 1,537
- Chaparro, Manuel Carlos 1,477 results 1,477
- Banerjee, S. 1,473 results 1,473
- Gershtein, Y. 1,471 results 1,471
- Harder, K. 1,471 results 1,471
- Hirosky, R. 1,471 results 1,471
- Malik, S. 1,471 results 1,471
- Parashar, N. 1,471 results 1,471
- Askew, A. 1,470 results 1,470
- Bean, A. 1,470 results 1,470
- Davies, G. 1,470 results 1,470
- Johnson, M. 1,470 results 1,470
- Narain, M. 1,470 results 1,470
- Barberis, E. 1,469 results 1,469
- Choi, S. 1,469 results 1,469
- Demina, R. 1,469 results 1,469
- Gerber, C. E. 1,469 results 1,469
- Meyer, A. 1,469 results 1,469
- Ruchti, R. 1,469 results 1,469
- Varelas, N. 1,469 results 1,469
- Hebbeker, T. 1,468 results 1,468
- Park, S. K. 1,468 results 1,468
- Wayne, M. 1,468 results 1,468
- Cutts, D. 1,467 results 1,467
- Bhat, P. C. 1,466 results 1,466
- Iashvili, I. 1,466 results 1,466
- Tully, C. 1,466 results 1,466
- Elvira, V. D. 1,464 results 1,464
- see all…
- Portuguese 876,299 results 876,299
- English 612,381 results 612,381
- Spanish 26,038 results 26,038
- French 4,370 results 4,370
- Italian 922 results 922
- German 431 results 431
- Multiple languages 132 results 132
- Undetermined 123 results 123
- Russian 23 results 23
- Galician 14 results 14
- Catalan 10 results 10
- Chinese 9 results 9
- Persian 8 results 8
- Hungarian 5 results 5
- Polish 5 results 5
- Japanese 3 results 3
- Chinese 2 results 2
- Lithuanian 2 results 2
- Dutch 2 results 2
- Romanian, Moldovan 2 results 2
- Aleut 1 results 1
- Arabic 1 results 1
- Bosnian 1 results 1
- Czech 1 results 1
- Croatian 1 results 1
- Latin 1 results 1
- Norwegian 1 results 1
- Persian 1 results 1
- Persian Sign Language 1 results 1
- Romanian Sign Language 1 results 1
- see all…
- Portugal 11,335 results 11,335
- Brasil 7,972 results 7,972
- Brazil 7,949 results 7,949
- COVID-19 7,429 results 7,429
- Enfermagem 6,868 results 6,868
- Artigos 6,625 results 6,625
- Artigo original 6,474 results 6,474
- Educação 5,813 results 5,813
- Nursing 5,126 results 5,126
- - 4,904 results 4,904
- Economia 4,354 results 4,354
- SDG 3 - Good Health and Well-being 4,082 results 4,082
- Education 4,077 results 4,077
- Criança 3,980 results 3,980
- Idoso 3,928 results 3,928
- Humans 3,539 results 3,539
- Epidemiology 3,412 results 3,412
- Ensino 3,368 results 3,368
- Child 3,337 results 3,337
- Epidemiologia 2,963 results 2,963
- Psicologia 2,841 results 2,841
- Aged 2,750 results 2,750
- História 2,726 results 2,726
- Adolescent 2,698 results 2,698
- Adolescente 2,695 results 2,695
- Comunicação 2,668 results 2,668
- HIV 2,532 results 2,532
- Qualidade de vida 2,453 results 2,453
- Obesity 2,437 results 2,437
- Teaching 2,373 results 2,373
- see all…
- Oasisbr 1,093,625 results 1,093,625
- RepositóriUM - Universidade do Minho 32,264 results 32,264
- Repositório da Universidade de Lisboa 27,647 results 27,647
- SciELO Portugal 25,110 results 25,110
- Repositório Aberto da Universidade do Porto 24,706 results 24,706
- Repositório Institucional da UNL 22,321 results 22,321
- Estudo Geral - Universidade de Coimbra 22,242 results 22,242
- Repositório Científico da Universidade de Évora 17,068 results 17,068
- RIA - Repositório Institucional da Universidade de Aveiro 14,265 results 14,265
- Veritati - Repositório Institucional da Universidade Católica Portuguesa 12,252 results 12,252
- Sapientia - Universidade do Algarve 11,840 results 11,840
- Biblioteca Digital da UPB 7,547 results 7,547
- Repositório Científico do Instituto Politécnico do Porto 7,048 results 7,048
- Repositório Científico da Universidade Politécnica de Lisboa 5,919 results 5,919
- Acta Médica Portuguesa 5,466 results 5,466
- Repositório do Ispa - Instituto Universitário 4,867 results 4,867
- ReCiL - Repositório Científico Lusófona 4,836 results 4,836
- Repositório Aberto da Universidade Aberta 4,811 results 4,811
- Theologica 4,745 results 4,745
- IC-online 4,351 results 4,351
- Repositório do Centro Hospitalar de Lisboa Central, EPE 3,955 results 3,955
- Repositório Científico do Instituto Nacional de Saúde 3,516 results 3,516
- Camões - Repositório Institucional da Universidade Autónoma de Lisboa 3,458 results 3,458
- Repositório Científico da Universidade Politécnica de Viseu 3,009 results 3,009
- Repositório Científico da Universidade Politécnica de Castelo Branco 2,979 results 2,979
- Lusíada - Repositório das Universidades Lusíada 2,846 results 2,846
- Análise Social 2,655 results 2,655
- DigitUMa - Repositório da Universidade da Madeira 2,591 results 2,591
- Repositório Institucional da Fernando Pessoa 2,567 results 2,567
- Repositório da Universidade dos Açores 2,529 results 2,529
- see all…
- IBICT 1,093,625 results 1,093,625
- Universidade do Minho 32,264 results 32,264
- Universidade do Porto 31,473 results 31,473
- Universidade de Lisboa 30,302 results 30,302
- Universidade Católica Portuguesa 25,700 results 25,700
- Fundação para a Ciência e Tecnologia 25,110 results 25,110
- Universidade de Coimbra 22,582 results 22,582
- Universidade Nova de Lisboa 22,321 results 22,321
- Universidade de Aveiro 18,551 results 18,551
- Universidade de Évora 17,068 results 17,068
- Universidade do Algarve 11,840 results 11,840
- Imprensa da Universidade de Coimbra 9,136 results 9,136
- Universidade Politécnica de Bragança 7,547 results 7,547
- Instituto Politécnico do Porto 7,048 results 7,048
- Universidade Politécnica de Lisboa 5,919 results 5,919
- Ordem dos Médicos 5,466 results 5,466
- Ispa-Instituto Universitário 4,867 results 4,867
- Grupo Lusófona 4,836 results 4,836
- Universidade Aberta 4,811 results 4,811
- Universidade de Leiria e Oeste 4,351 results 4,351
- Cogitatio Press 4,026 results 4,026
- Centro Hospitalar de Lisboa Central, EPE (CHLC) 3,955 results 3,955
- Instituto Nacional de Saúde Doutor Ricardo Jorge 3,516 results 3,516
- Universidade Autónoma de Lisboa 3,458 results 3,458
- Universidade Politécnica de Viseu 3,009 results 3,009
- Universidade Politécnica de Castelo Branco 2,979 results 2,979
- Universidade Fernando Pessoa 2,891 results 2,891
- Universidades Lusíada 2,846 results 2,846
- Instituto da Defesa Nacional 2,693 results 2,693
- Universidade da Madeira 2,591 results 2,591
- see all…
- Fundação para a Ciência e a Tecnologia 19,015 results 19,015
- European Commission 2,366 results 2,366
- Fundação para a Ciência e a Tecnologia, I.P. 1,170 results 1,170
- European Commission 139 results 139
- Wellcome Trust 21 results 21
- UK Research and Innovation 7 results 7
- National Institutes of Health 6 results 6
- Swiss National Science Foundation 6 results 6
- Danmarks Frie Forskningsfond 4 results 4
- Netherlands Organisation for Scientific Research (NWO) 4 results 4
- Research Council of Finland 3 results 3
- Agence Nationale de la Recherche 2 results 2
- Deutsche Forschungsgemeinschaft 2 results 2
- Science Foundation Ireland 2 results 2
- The Research Council of Norway 2 results 2
- U.S. National Science Foundation 2 results 2
- Australian Research Council 1 results 1
- Carlsberg Foundation 1 results 1
- FWF Austrian Science Fund 1 results 1
- Ministarstvo znanosti, obrazovanja i mladih 1 results 1
- Ministry of Education, Science, and Technological Development 1 results 1
- Ministry of Science, Technological Development, and Innovation 1 results 1
- Novo Nordisk Foundation 1 results 1
- see all…
- 6817 - DCRRNI ID 13,601 results 13,601
- 3599-PPCDT 2,380 results 2,380
- H2020 1,604 results 1,604
- OE 1,451 results 1,451
- FP7 861 results 861
- 5876 676 results 676
- Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017/2018) - Financiamento Base 630 results 630
- 5876-PPCDTI 546 results 546
- CEEC IND 2017 459 results 459
- DL 57/2016 452 results 452
- 9471 - RIDTI 414 results 414
- FARH 409 results 409
- POR_NORTE 391 results 391
- Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017/2018) - Financiamento Programático 359 results 359
- Concurso para Atribuição do Estatuto e Financiamento de Laboratórios Associados (LA) 329 results 329
- POCI 310 results 310
- SFRH 300 results 300
- POR_CENTRO 286 results 286
- Avaliação UID 2023/2024 284 results 284
- Bolsa de Doutoramento 270 results 270
- CEEC IND 3ed 260 results 260
- Investigador FCT 252 results 252
- CEEC IND 2018 223 results 223
- CEEC INST 2018 204 results 204
- 6820 - DCRRNI ID 201 results 201
- CEEC IND4ed 197 results 197
- Concurso para Financiamento de Projetos de Investigação Científica e Desenvolvimento Tecnológico em Todos os Domínios Científicos - 2017 161 results 161
- CEEC IND5ed 149 results 149
- COMPETE 116 results 116
- Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017/2018) - Financiamento Base 106 results 106
- see all…