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Dos Santos F.N.,INESC Porto | Dos Santos F.N.,University of Porto | Sobreira H.,INESC Porto | Sobreira H.,University of Porto | And 7 more authors.
Journal of Intelligent and Robotic Systems: Theory and Applications

Develop ground robots for crop monitoring and harvesting in steep slope vineyards is a complex challenge. Because of two main reasons: harsh condition of the terrain and unstable localization accuracy got from Global Positioning Systems (GPS). This paper presents a hybrid SLAM (VineSLAM) considering low cost landmarks to increase the robot localization accuracy, robustness and redundancy on these steep slope vineyards. Also, we present a cost-effective robot to carry-out crop monitoring tasks in steep slope vineyard environment. Test results got in a simulated and in a real test case supports the proposed approach and robot. © 2016 Springer Science+Business Media Dordrecht Source

Dos Santos F.N.,INESC Porto | Sobreira H.,INESC Porto | Campos D.,INESC Porto | Morais R.,University of Tras os Montes e Alto Douro | And 2 more authors.
Proceedings - 2015 IEEE International Conference on Autonomous Robot Systems and Competitions, ICARSC 2015

Crop monitoring and harvesting by ground robots on mountain vineyards is an intrinsically complex challenge, due to two main reasons: harsh conditions of the terrain and reduced time availability and unstable localization accuracy of the GPS system. In this paper is presented a cost effective robot that can be used on these mountain vineyards for crop monitoring tasks. Also it is explored a natural vineyard feature as the input of a standard 2D simultaneous localization and mapping approach (SLAM) for feature-based map extraction. In order to be possible to evaluate these natural features for mapping and localization purposes, a virtual scenario under ROS/Gazebo has been built and described. A low cost artificial landmark and an hybrid SLAM is proposed to increase the localization accuracy, robustness and redundancy on these mountain vineyards. The obtained results, on the simulation framework, validates the use of a localization system based on natural mountain vineyard features. © 2015 IEEE. Source

Ferra J.M.M.,University of Porto | Ohlmeyer M.,Johann Heinrich Von Thunen Institute | Mendes A.M.,University of Porto | Costa M.R.N.,University of Porto | And 3 more authors.
International Journal of Adhesion and Adhesives

In the open literature, two main strategies can be found for synthesizing urea-formaldehyde (UF) resins. One is the alkalineacid process, which takes place in three steps, usually an alkaline methylolation followed by an acid condensation and then the addition of a final amount of urea. The other process consists of four steps, the main difference being an initial condensation in strongly acid environment. In this work, we evaluate the curing behaviour of four resins produced using the aforementioned processes by the Integrated Pressing and Testing System (IPATES) and the Automated Bonding Evaluation System (ABES). The characterisation of the bond strength development during hot pressing by ABES and IPATES shows that the four resins will have different performances in the bonding process of wood-based composites. For each resin, the effect of pressing parameters such as temperature, adhesive and hardener ratios on shear strength (ABES) and internal bond (IPATES) during hot pressing is put into evidence. © 2010 Elsevier Ltd. All rights reserved. Source

Santos L.F.,Tondela Viseu Hospital Center | Rodrigues B.,Tondela Viseu Hospital Center | Moreira D.,Tondela Viseu Hospital Center | Correia E.,Tondela Viseu Hospital Center | And 10 more authors.

AimsBrugada syndrome (BrS) is a life-threatening arrhythmia disorder associated with autosomal-dominant mutations in the SCN5A gene. We aimed to characterize the diagnostic challenges and clinical manifestations of a novel SCN5A mutation associated with BrS.Methods and resultsFrom a novel SCN5A mutation (c.664C>T; p.Arg222X) identified in a proband with the characteristic electrocardiographic pattern and the history of sudden collapse, 122 family members were studied including 40 carriers of the mutation. The electrocardiographic diagnosis of BrS requires type 1 Brugada electrocardiogram (ECG) pattern in >1 right precordial lead (V1V3), but recently an isolated lead with coved-type ECG was proposed to be enough for the diagnosis. In this family, these proposed criteria (PC) were more sensitive in detecting mutation carriers than the conventional criteria without repercussion on the specificity. Carriers had, on average, longer P-wave duration, PR, and QRS intervals and higher transmural dispersion of repolarization. The prevalence of late potentials was higher in carriers, and individual signal average ECG (SAECG) parameters (QRSf, LAS, and RMS40) also were related to SCN5A gene mutation. Three non-carriers were found to be affected by BrS, two with a spontaneous type 1 ECG with alternative placement of the precordial electrodes, and one only after the pharmacological provocative test, suggesting that other genes may play a role in the pathophysiology of this disease.ConclusionThe PC for BrS diagnosis should be implemented. Some parameters from the spontaneous ECG and the SAECG are more effective tools than the characteristic repolarization pattern to discriminate between carriers of SCN5A mutations. © The Author 2012. Source

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