2019
Authors
Pedrosa, J; Duchenne, J; Queiros, S; Degtiarova, G; Gheysens, O; Claus, P; Voigt, JU; D'hooge, J;
Publication
PHYSICS IN MEDICINE AND BIOLOGY
Abstract
Regional contribution to left ventricular (LV) ejection is of much clinical importance but its assessment is notably challenging. While deformation imaging is often used, this does not take into account loading conditions. Recently, a method for intraventricular pressure estimation was proposed, thus allowing for loading conditions to be taken into account in a non-invasive way. In this work, a method for 3D automatic myocardial performance mapping in echocardiography is proposed by performing 3D myocardial segmentation and tracking, thus giving access to local geometry and strain. This is then used to assess local LV stress-strain relationships which can be seen as a measure of local myocardial work. The proposed method was validated against F-18-fluorodeoxyglucose positron emission tomography, the reference method to clinically assess local metabolism. Averaged over all patients, the mean correlation between FDG-PET and the proposed method was 0.67 +/- 0.18. In conclusion, stress-strain loops were, for the first time, estimated from 3D echocardiography and correlated to the clinical gold standard for local metabolism, showing the future potential of real-time 3D echocardiography ( RT3DE) for the assessment of local metabolic activity of the heart.
2019
Authors
Santos, L; Santos, FN; Filipe, V; Shinde, P;
Publication
PROGRESS IN ARTIFICIAL INTELLIGENCE, EPIA 2019, PT I
Abstract
Steep slope vineyards are a complex scenario for the development of ground robots due to the harsh terrain conditions and unstable localization systems. Automate vineyard tasks (like monitoring, pruning, spraying, and harvesting) requires advanced robotic path planning approaches. These approaches usually resort to Simultaneous Localization and Mapping (SLAM) techniques to acquire environment information, which requires previous navigation of the robot through the entire vineyard. The analysis of satellite or aerial images could represent an alternative to SLAM techniques, to build the first version of occupation grid map (needed by robots). The state of the art for aerial vineyard images analysis is limited to flat vineyards with straight vine’s row. This work considers a machine learning based approach (SVM classifier with Local Binary Pattern (LBP) based descriptor) to perform the vineyard segmentation from public satellite imagery. In the experiments with a dataset of satellite images from vineyards of Douro region, the proposed method achieved accuracy over 90%. © Springer Nature Switzerland AG 2019.
2019
Authors
Carneiro, JF; Pinto, JB; de Almeida, FG; Cruz, N;
Publication
OCEANS 2019 - MARSEILLE
Abstract
Autonomous underwater vehicles (AUVs) are becoming increasingly ubiquitous due to the growing needs in exploring Ocean resources. One of the most challenging tasks in this domain relates to the energy these vehicles require, given the increase in the number of scientific payloads and on the mission complexity. One way to potentially reduce the amount of energy consumed during vertical motion is to replace or complement the thruster action with a controlled change of the vehicles floatation, using a variable buoyancy system (VBS). This paper presents the development of an electromechanical VBS for shallow depths, up to 100 m, to be included in an existing AUV. A preliminary mechanical design is presented, along with a mathematical model allowing the calculation of the energy spent by this device, based on the components manufacturers' data. A comparison between the energy consumption using thrusters and the designed VBS is presented. © 2019 IEEE.
2019
Authors
Valente, G; Leite, C; Cardoso, M; Martins, AL; Moreira, F; Au Yong Oliveira, M;
Publication
Iberian Conference on Information Systems and Technologies, CISTI
Abstract
This study focuses on the impact of technology and on the planning of a trip by a Portuguese tourist. From the literature review, studies done at the European level, the technology inherent to tourism is provided to the entire age range, and fundamentally to the planning of accommodation, transport and tourist packs. The absorption of information is always highlighted by the easy and fast access to the Internet increasingly accessible to anyone, promoting behavioral changes in tourism planning. Thus, an online survey (with 180 valid answers) was carried out, which focused mainly on university students, and was restricted to Portuguese citizens. The survey determined that online platforms are most used for accommodation (87.2%), transportation (87,2%) and the demand for information (68.8%) to the detriment of catering (7.3%), and these are mainly being used because of their speed (79.4%) and simplicity (80.7%). To conclude, our study confirms the bibliographic review, and it was determined that practically all respondents assume the influence of digital platforms in the planning of their trips (99.1%), with 89% going further and affirming that in the future all planning will be carried out in an exclusive way online. © 2019 AISTI.
2019
Authors
Goncalves, RMP; Varela, MLR; Madureira, AM; Putnik, GD; Machado, J;
Publication
ADVANCES IN MANUFACTURING II, VOL 1 - SOLUTIONS FOR INDUSTRY 4.0
Abstract
The domain of Production Planning and Control, or in a broader sence Production Management has been deserving a special and increasing attention by the companies, which intend to continuously achieve better results through continuous improvement, which also fits in the context of Industry 4.0. Companies tend to implement management systems with the purpose of achieving greater competitiveness and, consequently, greater sustainability in their sector. The selection of the appropriate production management system is a serious problem for the companies. The main objective of this study is to support companies in the correct choice of a Decision Support System. The method used to achieve the proposed objective consists on formulating a model for comparing functionalities and specifications, where selection of criteria were also defined and analyzed. Based on a large Company scenario, the model is applied to three production execution systems: SAP PP (Systems Applications and Products - Production Planning), Prodsmart and GenSYS.
2019
Authors
He, H; Li, SC; Hu, L; Duarte, N; Manta, O; Yue, XG;
Publication
SUSTAINABILITY
Abstract
In order to investigate the factors influencing the sustainable guarantee network and its differences in different spatial and temporal scales, logistic regression algorithm is used to analyze the data of listed companies in 31 provinces, municipalities and autonomous regions in China from 2008 to 2017 (excluding Hong Kong, Macau and Taiwan). The study finds that, overall, companies with better profitability, poor solvency, poor operational capability and higher levels of economic development are more likely to join the guarantee network. On the temporal scale, solvency and regional economic development exert increasing higher impact on the companies' accession to the guarantee network, and operational capacity has increasingly smaller impact. On the spatial scale, the less close link between company executives and companies in the western region suggests higher possibility to join the guarantee network. The predictive accuracy test results of the logistic regression algorithm show that the training model of the western sample enterprises has the highest prediction accuracy when predicting enterprise behavior of joining the guarantee network, while the accuracy is the lowest in the central region. When forecasting enterprises' failure to join the guarantee network, the training model of the central sample enterprise has the highest accuracy, while the accuracy is the lowest in the eastern region. This paper discusses the internal and external factors influencing the guarantee network risk from the perspective of spatial and temporal differences of the guarantee network, and discriminates the prediction accuracy of the training model, which means certain guiding significance for listed company management, bank and government to identify and control the guarantee network risk.
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