Search results for " Accuracy"
showing 10 items of 165 documents
Influence of some relevant process parameters on the dimensional accuracy in incremental forming: a numerical and experimental investigation
2004
Abstract As known, incremental forming is a flexible and innovative sheet metal forming process which allows complex shape shells forming without the need for any die. For these reasons, incremental forming is nowadays suggested for rapid prototyping and customised products. The present paper is focused on material formability in incremental forming and, in particular, on the evaluation and compensation of elastic springback. The latter significantly modifies the imposed shape. For this purpose, a deeper assessment of the process was developed following three different approaches. First of all, a wide experimental investigation on the influence of some relevant process parameters was develo…
Predicting risk and outcomes for frail older adults: a protocol for an umbrella review of available frailty screening tools
2015
REVIEW QUESTION / OBJECTIVE The aim of this systematic review is to comprehensively search the available literature and to summarize the best available evidence from systematic reviews in relation to published screening tools to identify pre-frailty and frailty in older adults, that is: (i) to determine their psychometric proprieties; (ii) to assess their capacity to detect pre-frail and frail conditions against established methods; and (iii) to evaluate their predictive ability. More specifically, the review will focus on the following questions: - What is the reliability and validity of existing screening tools that assess pre-frailty/frailty in older patients? - How sensitive and specif…
Comparative in vitro study of the accuracy of impression techniques for dental implants: Direct technique with an elastomeric impression material ver…
2019
Background The aim of this study was to compare a conventional technique (elastomeric impression material - EIM) and a digital technique (scanner digital model – SDM) on a six-analog master model (MM) to determine which was the most exact. Material and Methods Twenty impressions were taken of a master model (EIM) and twenty scanned impressions (SDM) (True Definition). A coordinate measuring machine (CMM) was used to measure the distances between adjacent analogues (1-2, 2-3, 3-4, 4-5, 5-6), intermittently positioned analogues (1-4, 3-6) and the most distal (1-6). Reference values were established from the master model, which were compared with the two impression techniques. The significance…
The use of vineyard spectral signatures to identify table grape cultivars
2021
Vineyards have characteristic responses to sunlight. The reflectance values at the different wavelengths are typical of vegetation and define its spectral signature. The aim of this work was to determine the spectral signatures of table grape vineyards located in the production area of Robinvale (Victoria, Australia) in order to identify cultivars in the vineyard. Spectral signatures were detected from images in eight bands from the Worldview 3 platform. Spectral signatures for a representative number of plots were extracted using satellite reflectance images for each cultivar. Spectral signatures were also collected in the field, from the same cultivars, with a FieldSpec® HandHeld 2 portab…
Off-line scan path planning for robotic NDT
2018
This work presents computer-aided scan path generation for robotic non-destructive testing of complex shaped test-pieces. Off-line programmed scan path was used to robotically inspect an aluminium fixed leading edge skin panel of an aircraft wing by means of swept frequency eddy currents method. Eddy currents probe was deployed by means of a six-axis robotic arm KUKA KR5 arc. Reverse engineering of the test-piece was carried out to reconstruct CAD model of its surface. Positioning accuracy of the performed continuous scan was measured with a laser tracker in accordance with ISO 9283:1998 and is reported in the paper. The positional uncertainty of the NDT scan calculated as the standard devi…
Computer assisted diagnosis (CAD) in mammography. Comparison of diagnostic accuracy of a new algorithm (Cyclopus(R), Medicad) with two commercial sys…
2008
The study compares the diagnostic accuracy (correct identification of cancer) of a new computer-assisted diagnosis (CAD) system (Cyclopus) with two other commercial systems (R2 and CADx). Cyclopus was tested on a set of 120 mammograms on which the two compared commercial systems had been previously tested. The set consisted of mammograms reported as negative, preceding 31 interval cancers reviewed as screening error or minimal sign, and of 89 verified negative controls randomly selected from the same screening database. Cyclopus sensitivity was 74.1% (R2=54.8%; CADx=41.9%) and was higher for interval cancers reviewed as screening error (90.9%; R2=54.5%; CADx=81.8%) compared with those revie…
Some numerical modelings beyond the mesh
2015
In recent years meshless methods have gained much attention in several application areas of science. These methods benefit of savings due to the elimination of meshing process and are suite to handle changes in the geometry of the domain of interest. Further advantages come from the ease of implementation, which makes computer codes very flexible. We present some numerical experiences lying in the meshless framework dealing with domain and boundary-type methods.
An Instrument-Assisted coracoid pain test: an exploratory diagnostic accuracy study
2022
The coracoid pain test (CPT) could contribute to the diagnosis of frozen shoulder (FS) with palpation. However, due to assessor performance these values might be unreliable. Therefore, the aim was to explore the diagnostic accuracy of an instrument-assisted CPT and two alternative approaches (pain severity and side comparison) for assistance in the diagnosis of FS. Patients with FS and healthy age-matched controls were recruited. All participants underwent the instrument-assisted CPT on both shoulders with a pressure algometer. Sensitivity, specificity, and likelihood ratios were determined for the three approaches. In total, 35 patients with FS and 35 healthy participants were included. Th…
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…