Search results for "Cg"
showing 10 items of 999 documents
On the reducibility of geometric constraint graphs
2018
Geometric modeling by constraints, whose applications are of interest to communities from various fields such as mechanical engineering, computer aided design, symbolic computation or molecular chemistry, is now integrated into standard modeling tools. In this discipline, a geometric form is specified by the relations that the components of this form must verify instead of explicitly specifying these components. The purpose of the resolution is to deduce the form satisfying all these constraints. Various methods have been proposed to solve this problem. We will focus on the so-called graph-based or graph-based methods with application to the two-dimensional space.
Optimal rates of convergence for persistence diagrams in Topological Data Analysis
2013
Computational topology has recently known an important development toward data analysis, giving birth to the field of topological data analysis. Topological persistence, or persistent homology, appears as a fundamental tool in this field. In this paper, we study topological persistence in general metric spaces, with a statistical approach. We show that the use of persistent homology can be naturally considered in general statistical frameworks and persistence diagrams can be used as statistics with interesting convergence properties. Some numerical experiments are performed in various contexts to illustrate our results.
Computation of the topological type of a real Riemann surface
2012
We present an algorithm for the computation of the topological type of a real compact Riemann surface associated to an algebraic curve, i.e., its genus and the properties of the set of fixed points of the anti-holomorphic involution $\tau$, namely, the number of its connected components, and whether this set divides the surface into one or two connected components. This is achieved by transforming an arbitrary canonical homology basis to a homology basis where the $\mathcal{A}$-cycles are invariant under the anti-holomorphic involution $\tau$.
How neurophysiological measures can be used to enhance the evaluation of remote tower solutions
2019
New solutions in operational environments are often, among objective measurements, evaluated by using subjective assessment and judgment from experts. Anyhow, it has been demonstrated that subjective measures suffer from poor resolution due to a high intra and inter-operator variability. Also, performance measures, if available, could provide just partial information, since an operator could achieve the same performance but experiencing a different workload. In this study, we aimed to demonstrate: (i) the higher resolution of neurophysiological measures in comparison to subjective ones; and (ii) how the simultaneous employment of neurophysiological measures and behavioral ones could allow a…
Wireless ECG and cardiac monitoring systems: State of the art, available commercial devices and useful electronic components
2021
Abstract Wireless ElectroCardioGram (ECG) systems are employed in manifold application fields: tele-monitoring, sport applications, support to ageing people at home, fetal ECG, wearable devices and ambulatory monitoring. The presence of cables often hinders user’s free movements, alongside clinicians’ routine operations. Therefore, wireless ECG systems are desirable. This paper aims at reviewing the solutions described in the literature, besides commercially available devices and electronic components useful to setup laboratory prototypes. Several systems have been developed, different in terms of the adopted technology; when approaching the development of a wireless ECG system, some import…
New Method of Microimages Generation for 3D Display
2018
In this paper, we propose a new method for the generation of microimages, which processes real 3D scenes captured with any method that permits the extraction of its depth information. The depth map of the scene, together with its color information, is used to create a point cloud. A set of elemental images of this point cloud is captured synthetically and from it the microimages are computed. The main feature of this method is that the reference plane of displayed images can be set at will, while the empty pixels are avoided. Another advantage of the method is that the center point of displayed images and also their scale and field of view can be set. To show the final results, a 3D InI dis…
Untersuchungen zur Reliabilität von Mustererkennungs-Algorithmen für die P-Wellen orthogonaler Elektrokardiogramme
1979
On the Reliability of Pattern Recognition Algorithms for ECGs Judging the performance of pattern recognition algorithms in ECG analysis on an objective basis still presents a severe problem because of the heuristic nature of the criteria used- The paper illustrates that problem by way of P-wave detectors for ECGs. We want to focus on the external reliability of the algorithms. The term external reliability is closely related to condition or robustness. Here we are interested in the variation of the output of an algorithm when the input data are slightly altered. This pertains to the problem of how the biological variance of the ECGs is mapped into the variance of algorithm output. We may sa…
Low invasive multisensor acquisition system for real-time monitoring of cardiovascular and respiratory parameters
2020
The recent advances in multiparametric monitoring of biosignals and management of big data prompt for the development of devices and techniques for the extraction of indicators with physiological relevance. In this context, we have designed and realized a portable electronic system, equipped with simple biomedical sensors, able to synchronously record multiple electrocardiographic (ECG), photoplethysmographic (PPG) and breathing signals, for carrying out a non-invasive monitoring of several cardiovascular parameters. In this work, we show the results of preliminary measurements performed following a specific physiological protocol (i.e., deep breathing with 10 s per cycle). The system allow…
Adaptive Threshold, Wavelet and Hilbert Transform for QRS Detection in Electrocardiogram Signals
2017
This paper combines Hilbert and Wavelet transforms and an adaptive threshold technique to detect the QRS complex of electrocardiogram signals. The method is performed in a window framework. First, the Wavelet transform is applied to the ECG signal to remove noise. Next, the Hilbert transform is applied to detect dominant peak points in the signal. Finally, the adaptive threshold technique is applied to detect R-peaks, Q, and S points. The performance of the algorithm is evaluated against the MIT-BIH arrhythmia database, and the numerical results indicated significant detection accuracy.
ChiLab4It system in the QA4FAQ competition
2017
ChiLab4It is the Question Answering system (QA) for Frequently Asked Questions (FAQ) developed by the Computer-Human Interaction Laboratory (ChiLab) at the University of Palermo for participating to the QA4FAQ task at EVALITA 2016 competition. The system is the versioning of the QuASIt framework developed by the same authors, which has been customized to address the particular task. This technical report describes the strategies that have been imported from QuASIt for implementing ChiLab4It, the actual system implementation, and the comparative evaluations with the results of the other participant tools, as provided by the organizers of the task. ChiLab4It was the only system whose score re…