Search results for "ACCURACY"
showing 10 items of 277 documents
Cell-average WENO with progressive order of accuracy close to discontinuities with applications to signal processing
2020
In this paper we translate to the cell-average setting the algorithm for the point-value discretization presented in S. Amat, J. Ruiz, C.-W. Shu, D. F. Y\'a\~nez, A new WENO-2r algorithm with progressive order of accuracy close to discontinuities, submitted to SIAM J. Numer. Anal.. This new strategy tries to improve the results of WENO-($2r-1$) algorithm close to the singularities, resulting in an optimal order of accuracy at these zones. The main idea is to modify the optimal weights so that they have a nonlinear expression that depends on the position of the discontinuities. In this paper we study the application of the new algorithm to signal processing using Harten's multiresolution. Se…
Effetto della cultivar e del regime colturale sulla risposta spettrale della chioma in Vitis vinifera L.
2008
Lo studio consente di caratterizzare le risposte spettrali all’invaiatura di chioma ed acino di alcune cultivar a bacca nera della piattaforma ampelografica siciliana. La variabilità tra le risposte spettrali delle foglie all’interno della stessa chioma, nonché le variazioni spettrali anche al variare del regime irriguo consentono di effettuare un’analisi comparativa delle cultivar. In questo quadro, le firme spettrali integrano la descrizione ampelografica di chioma e bacche che caratterizza la Vitis Vinifera L.. Infine l’applicazione su un’area pilota di tecniche di classificazione di immagini remote basate sulle caratteristiche spettrali delle cultivar, consente di valutarne le performan…
First Experiences on an Accurate SPH Method on GPUs
2017
It is well known that the standard formulation of the Smoothed Particle Hydrodynamics is usually poor when scattered data distribution is considered or when the approximation near the boundary occurs. Moreover, the method is computational demanding when a high number of data sites and evaluation points are employed. In this paper an enhanced version of the method is proposed improving the accuracy and the efficiency by using a HPC environment. Our implementation exploits the processing power of GPUs for the basic computational kernel resolution. The performance gain demonstrates the method to be accurate and suitable to deal with large sets of data.
Some efficient algorithms for the solution of a single nonlinear equation
1981
High order methods for the numerical solution of nonlinear scalar equations are proposed which are more efficient than known procedures, and a unified approach to various methods suggested in literature is given.
Information Exchange Supply Chain under inventory inaccuracy: a simulation study
2012
The objective of this paper is to contribute at quantifying the impact of inventory record inaccuracy on operational performance and customer service level in collaborative supply chains. To this purpose we analyse the impact of shrinkage errors in the inventory item recording activity in an “information exchange supply chain”, i.e. a supply chain in which companies share information about market demand and use such information for placing orders to their suppliers. We present the mathematical formulation of such a supply chain model and we conduct a numerical simulation and a sensitivity analysis over different level of errors.
Comparative study of several programs used in the potentiometric evaluation of equilibrium constants including an error sensitivity analysis
1989
Abstract The programs MINIQUAD, MINIPOT, SUPERQUAD and PHCONST are applied to the evaluation of the protonation constants of several hypothetical polyprotic substances using simulated titrations, and the precision and accuracy of the results are discussed and compared. When statistical weights are used the results are very similar, the accuracy being better with PHCONST. Error sensitivity analysis was used as a means of establishing the influence of a systematic error of an experimental variable on the accuracy of the determination. An algorithm for the accurate calculation of error sensitivities is proposed and checked. Error sensitivities can be used to make a choice between the various m…
Google Searches for Taste and Smell Loss Anticipate Covid-19 Epidemiology
2020
AbstractBackgroundAs evidence emerged that loss of taste and/or loss of smell is frequently triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we investigated whether Google searches volume for these two disease-specific symptoms could be associated with disease epidemiology in United States (US).Materials and MethodsWe performed an electronic search in Google Trends using the keywords “taste loss” and “smell loss” within the US. The Google searches volume was correlated with the number of new weekly cases of coronavirus disease 2019 (COVID-19) in the country.ResultsThe weekly Google searches for taste and smell loss exhibited a trend similar to that of new…
Methods for diagnosing bile acid malabsorption: a systematic review
2019
Abstract Background Bile acid malabsorption (BAM) and bile acid-related diarrhea represent an under-recognized cause of chronic diarrhea mainly because of limited guidance on appropriate diagnostic and laboratory tests. We aimed to perform a systematic review of the literature in order to identify and compare the diagnostic accuracy of different diagnostic methods for patients with BAM, despite a proven gold standard test is still lacking. Methods A PubMed literature review and a manual search were carried out. Relevant full papers, evaluating the diagnostic accuracy of different methods for BAM, were assessed. Available data were analyzed to estimate the sensitivity and specificity of each…
Day-to-Day Variability and Year-to-Year Reproducibility of Accelerometer-Measured Free-Living Sit-to-Stand Transitions Volume and Intensity among Com…
2021
(1) Background: The purpose of this study was to evaluate the day-to-day variability and year-to-year reproducibility of an accelerometer-based algorithm for sit-to-stand (STS) transitions in a free-living environment among community-dwelling older adults. (2) Methods: Free-living thigh-worn accelerometry was recorded for three to seven days in 86 (women n = 55) community-dwelling older adults, on two occasions separated by one year, to evaluate the long-term consistency of free-living behavior. (3) Results: Year-to-year intraclass correlation coefficients (ICC) for the number of STS transitions were 0.79 (95% confidence interval, 0.70-0.86, p < 0.001), for mean angular velocity-0.81 (95% c…
Range-based versus automated markerless image-based techniques for rock art documentation
2014
Nowadays there is a huge proliferation of fully automatic image-based solutions producing either three-dimensional (3D) point clouds or 3D models. However, the reliability of the output is not usually reported and clarified. This paper presents a comparison of the 3D modelling results achieved on two rock art shelters at separate archaeological sites using a high-resolution digital camera. The 3D point clouds were produced using automatic image-based photogrammetric and computer vision software running either locally (FOTOGIFLE and VisualSFM) or through a webbased reconstruction service (Autodesk 123D Catch). The first two automatic approaches are compared with a manual bundle block adjustm…