Search results for " Accuracy"

HIGH-ORDER ACCURATE EMBEDDED-BOUNDARY DISCONTINUOUS GALERKIN METHODS FOR INVISCID GAS DYNAMICS

2022

This work presents a computational framework for solving the equations of inviscid gas dynamics over embedded geometries based on the discontinuous Galerkin (DG) method. The novelty of the framework is the ability to achieve high-order accuracy in the regions of smooth flow and to handle the presence of solution discontinuities via suitably introduced damping terms, which allow controlling spurious oscillations that are typical of high-order methods for first-order hyperbolic PDEs. The framework employs block structured Cartesian grids where a level set function defines implicitly the considered geometry. The domain is partitioned by intersecting the grid and the level set function, such th…

An Online Time Warping based Map Matching for Vulnerable Road Users’ Safety

2018

International audience; High penetration rate of Smartphones and their increased capabilities to sense, compute, store and communicate have made the devices vital components of intelligent transportation systems. However, their GPS positions accuracy remains insufficient for a lot of location-based applications especially traffic safety ones. In this paper, we developed a new algorithm which is able to improve smartphones GPS accuracy for vulnerable road users' traffic safety. It is a two-stage algorithm: in the first stage GPS readings obtained from smartphones are passed through Kalman filter to smooth deviated reading. Then an adaptive online time warping based map matching is applied to…

FOCAL LIVER LESIONS: CONTRAST-ENHANCED ULTRASOUND

2008

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in sonography and it is being increasingly used for evaluation of focal liver lesions (FLLs). The unique feature of CEUS of non-invasively assessing in real time liver perfusion throughout the vascular phase has led to a dramatic improvement in diagnostic accuracy of US in either detection and characterization of FLLs, as well as in the guidance and evaluation of response of therapeutic procedures. Currently, CEUS is included as a part of the suggested diagnostic work-up of FLLs, resulting in a better patient management and cost-effective therapy delivering. After a brief description of the basis of different CEUS tec…

Fog Computing based traffic Safety for Connected Vulnerable Road Users

2019

Annually, millions of people die and many more sustain non-fatal injuries because of road traffic crashes. Despite multitude of countermeasures, the number of causalities and disabilities owing to traffic accidents are increasing each year causing grinding social, economic, and health problems. Due to their high volume and lack of protective-shells, more than half of road traffic deaths are imputed to vulnerable road users (VRUs): pedestrians, cyclists and motorcyclists. Mobile devices combined with fog computing can provide feasible solutions to protect VRUs by predicting collusions and warning users of an imminent traffic accident. Mobile devices’ ubiquity and high computational capabilit…

A semi-empirical multipurpose steady-state model of a fuel cell for household appliances

2013

In this paper, a multipurpose model of a proton exchange membrane fuel cell for household appliances is proposed. According to a conventional mathematical approach, the proposed model is derived from the physical and electro-chemical equations that rule the fuel cell behaviour. Differently from existing models, a parametric analysis is carried out and a few tunable parameters are accurately selected and identified. Furthermore, this paper proposes an innovative technique of unique model architecture which enables the designer to solve by himself the trade-off between complexity and accuracy on the basis of the specific applications. Three different choices could be performed by the designer…

A novel current-based approach for very low variation detection of resistive sensors in wheatstone bridge configuration

2014

Towards an accurate molecular orbital theory for excited states : Ethene, butadiene, and hexatriene

1993

A newly proposed quantum chemical approach for ab initio calculations of electronic spectra of molecular systems is applied to the molecules ethene, trans‐1,3‐butadiene, and trans‐trans‐1,3,5‐hexatriene. The method has the aim of being accurate to better than 0.5 eV for excitation energies and is expected to provide structural and physical data for the excited states with good reliability. The approach is based on the complete active space (CAS) SCF method, which gives a proper description of the major features in the electronic structure of the excited state, independent of its complexity, accounts for all near degeneracy effects, and includes full orbital relaxation. Remaining dynamic ele…

Human experts vs. machines in taxa recognition

2020

The step of expert taxa recognition currently slows down the response time of many bioassessments. Shifting to quicker and cheaper state-of-the-art machine learning approaches is still met with expert scepticism towards the ability and logic of machines. In our study, we investigate both the differences in accuracy and in the identification logic of taxonomic experts and machines. We propose a systematic approach utilizing deep Convolutional Neural Nets with the transfer learning paradigm and extensively evaluate it over a multi-pose taxonomic dataset with hierarchical labels specifically created for this comparison. We also study the prediction accuracy on different ranks of taxonomic hier…

A study on the effect of contact pressure during physical activity on photoplethysmographic heart rate measurements

2020

Heart rate (HR) as an important physiological indicator could properly describe global subject&rsquo

Accuracy and reliability in GNSS NRTK

2009

The work shows the results of testing conducted from 2008 to 2009 within the Network-based RTK GNSS of University of Palermo. The network is composed of eight Continuously Operating Reference Stations (CORS) located in western Sicily and managed by a Control Centre located at the Dipartimento di Rappresentazione (DIRAP) of University of Palermo. The main goal of the work is to verify the reliability of the CORS network (successful tests, failed initialization time, satellite configurations) and the accuracy of measurements positioning using VRS, FKP and Nearest Station techniques. The reliability was considered the probability that the operator can correctly determine its position within th…