Search results for "Efficient"
showing 10 items of 1603 documents
Exemples de QSAR sur des coefficients de partage
2005
National audience
Denoising AVIRIS-NG Data for Generation of New Chlorophyll Indices
2021
The availability of Airborne Visible and Infrared Imaging Spectrometer-Next Generation (AVIRIS-NG) data has enormous possibilities for quantification of Leaf Chlorophyll Content (LCC). The present study used the AVIRIS-NG campaign site of Western India for generation and validation of new chlorophyll indices by denoising the AVIRIS-NG data. For validation, concurrent to AVIRIS-NG flight overpass, field samplings were performed. The acquired AVIRIS-NG was subjected to Spectral Angle Mapper (SAM) classifier for discriminating the crop types. Three smoothing techniques i.e., Fast-Fourier Transform (FFT), Mean and Savitzky-Golay filters were evaluated for their denoising capability. Raw and fil…
Evaluation of Erythema Severity in Dermatoscopic Images of Canine Skin: Erythema Index Assessment and Image Sampling Reliability.
2021
The regular monitoring of erythema, one of the most important skin lesions in atopic (allergic) dogs, is essential for successful anti-allergic therapy. The smartphone-based dermatoscopy enables a convenient way to acquire quality images of erythematous skin. However, the image sampling to evaluate erythema severity is still done manually, introducing result variability. In this study, we investigated the correlation between the most popular erythema indices (EIs) and dermatologists’ erythema perception, and we measured intra- and inter-rater variability of the currently-used manual image-sampling methods (ISMs). We showed that the EIBRG, based on all three RGB (red, green, and blue) channe…
Role of apparent diffusion coefficient values in prostate diseases characterization on diffusion-weighted magnetic resonance imaging.
2019
BACKGROUND: To evaluate if normal and pathological prostate tissue can be distinguished by using apparent diffusion coefficient (ADC) values on magnetic resonance imaging (MRI) and to understand if it is possible to differentiate among pathological prostate tissues using ADC values.METHODS:Our population consisted in 81 patients (mean age 65.4 years) in which 84 suspicious areas were identified. Regions of interest were placed over suspicious areas, detected on MRI, and over areas with normal appearance, and ADC values were recorded. Statistical differences between ADC values of suspicious and normal areas were evaluated. Histopathological diagnosis, obtained from targeted biopsy using MRI-…
Neural network prediction of the AE index from the PC index
1999
Abstract It is shown that although the power spectra of the AE and PC data are quite similar they show differencies in structure function analysis. While the AE time series has a clear drop in the slope of the structure function (SF) after the first 2 hours, the slope of the SF of the PC data decreases gradually and at a little longer time scale. It is also shown by using 15-min averaged data, that both SFs are periodic with a clear diurnal variation. The PC time series seems to have a more pronounced periodicity, probably because it is measured at a single station at Thule. The AE index has been derived from the PC index for 7.5 minutes ahead by different methods. All these predictions gav…
Analysis of spectral irradiance distribution for PV applications at high latitude
2020
The spectral distribution of global tilted irradiance measured in Grimstad, Norway, is analyzed in terms of the average photon energy ( $APE$ ) blue fraction ( $BF$ ) and useful fraction ( $UF$ ). The results based on eight months of recorded data show a general shift of the $APE,\ BF$ , and $UF$ values to higher values than reference AM1.5G spectrum, with 1.63 eV, 0.45, and 0.88 being the average indices, respectively. The statistical coefficient of variation ( $CV$ ) is used to determine the variation of indices. The $CV$ for $APE,\ BF$ , and $UF$ are calculated to be 20.1%, 26.1%, and 25.7%, respectively confirming the earlier findings on $APE$ being a more accurate index for the quantif…
Online Estimation of the Mechanical Parameters of an Induction Machine Using Speed Loop characteristics and Recursive Least Square Technique
2022
This paper presents a novel approach for estimation of mechanical parameters, inertia and friction coefficient of an Induction Machine (IM) using speed loop characteristics and Recursive Least Square (RLS) estimator. Using the 5th order dynamic equation for Induction Machine and the forgetting factor based RLS algorithm the technique herein proposed employs the speed of the machine and the torque as the inputs for the estimator. Results obtained compares the estimated parameters with the actual parameters under multiple step varying and exponentially varying scenarios. Upon analyzing the results, the validity and the effectiveness of the proposed identification technique is confirmed
Monetary policy and the redistribution of net worth in the U.S
2021
The view that expansionary monetary policy can exacerbate both income and wealth inequality by increasing asset prices has become increasingly popular. The aim of this paper is to study the distributive effects of monetary policy on wealth inequality. In the first part of this research, we develop a simple framework based on accounting identity to examine the redistributive repercussions of changes in monetary policy on net worth through different channels. Based on this framework, in the second part of the paper, we show empirical evidence concerning the effects of monetary policy on wealth inequality in the US. To derive this, we combined macro and micro data, and proceeded in two steps. …
Controlling diffusion of 3He by buffer gases: a structural contrast agent in lung MRI.
2006
Purpose: To study the influence of admixing inert buffer gases to laser-polarized 3 He in terms of resulting diffusion coefficients and the consequences for image contrast and resolution. Materials and Methods: The diffusion coefficient of 3 He was altered by admixing buffer gases of various molecular weights ( 4 He, N2, and SF6). The influence of the pulse sequence and the diffusion coefficient on the appearance of MRI of (laserpolarized) gases was analyzed by comparison of basic theoretical concepts with demonstrative experiments. Results: Excellent agreement between theoretical description and observed signal in simple gradient echoes was observed. A maximum signal gain can be predicted …
Estimating field-saturated soil hydraulic conductivity by a simplified Beerkan infiltration experiment
2012
Field-saturated soil hydraulic conductivity, Kfs, is highly variable. Therefore, interpreting and simulating hydrological processes, such as rainfall excess generation, need a large number of Kfs data even at the plot scale. Simple and reasonably rapid experiments should be carried out in the field. In this investigation, a simple infiltration experiment with a ring inserted shortly into the soil and the estimation of the so-called α* parameter allowed to obtain an approximate measurement of Kfs. The theoretical approach was tested with reference to 149 sampling points established on Burundian soils. The estimated Kfs with the value of first approximation of α* for most agricultural field s…