Search results for "estimation"
showing 10 items of 924 documents
An assessment of the Beerkan method for determining the hydraulic properties of a sandy loam soil
2014
Abstract Establishing the ability of the Beerkan Estimation of Soil Transfer parameters (BEST) procedure to reproduce soil properties is necessary for specific soil types. In this investigation, the BEST predictions for a sandy loam soil were compared with water retention data obtained by a standard laboratory method and with the saturated soil hydraulic conductivity, K s , obtained by both the Wu et al. (1999) method, applied to the BEST infiltration data, and the Simplified Falling Head (SFH) technique. When the original BEST-slope algorithm with the infiltration constants fixed at β = 1.9 and γ = 0.79 was applied, the agreement between the predicted and the measured retention data was sa…
A test of the Beerkan Estimation of Soil Transfer parameters (BEST) procedure
2014
Abstract The Beerkan Estimation of Soil Transfer parameters (BEST) procedure is attractive for a simple soil hydraulic characterization but testing the ability of this procedure to estimate soil properties is necessary. The BEST predictions were compared with soil water retention and hydraulic conductivity data measured in the laboratory and the field, respectively, at ten Sicilian field sites. Provided that BEST yielded physically possible scale parameters of the soil characteristic curves in most of the four replicated infiltration runs at a site, the measured water retention was satisfactorily predicted (i.e., not statistically significant differences between measurements and predictions…
Skimager for the objective erythema estimation in atopic dogs
2020
In this study, the severity of canine skin erythema was assessed objectively for the first time. Atopic dermatitis (AD) is a common canine inflammatory and pruritic skin disease associated with an allergic reaction to exogenous allergens. The monitoring of skin erythema over time with lesion severity scales like the CADESI-4 is an essential diagnostic and research tool, especially for clinical trials. Currently, the erythema assessment is subjective due to visual estimation. In our study, we calculated the erythema index (EI) in 14 atopic dogs based on the analysis of multispectral skin images taken with the Skimager device. The relationship between the EI and a visual erythema estimation w…
Revisión de las formas abreviadas de la Escala de Inteligencia de Wechsler para Adultos
2016
RESUMEN: El presente trabajo tiene como objetivo presentar una revisión teórica de las principales formas abreviadas que han sido desarrolladas por varios autores a partir de las distintas versiones de la Escala de inteligencia de Wechsler para adultos que han ido surgiendo a lo largo del tiempo. El desarrollo de formas cortas ha ido creciendo en paralelo a la aparición de las nuevas versiones de la escala completa. Una forma abreviada permite estimar la capacidad intelectual con un tiempo de administración menor, por lo que puede ser de gran utilidad si el objetivo de evaluación es obtener una medida general de la capacidad intelectual.Wechsler Adult Intelligence Scale: Review of short for…
Automatic analysis of multiple Beerkan infiltration experiments for soil Hydraulic Characterization
2013
The BEST (Beerkan Estimation of Soil Transfer parameters) procedure of soil hydraulic characterization appears promising for intensively sample field areas with a reasonable effort both in terms of equipment and time passed in the field. Two alternative algorithms, i.e. BEST-slope and BEST-intercept, have been suggested to determine soil sorptivity and field-saturated soil hydraulic conductivity from a simply measured cumulative infiltration curve. With both algorithms, calculations have to be repeated also many times, depending on the number of collected infiltration data, that should vary between eight and 15. The need to consider a varying number of infiltration data is related to the fa…
Testing a new automated single ring infiltrometer for Beerkan infiltration experiments
2015
International audience; The Beerkan method along with BEST algorithms is an alternative technique to conventional laboratory or field measurements for rapid and low-cost estimation of soil hydraulic properties. The Beerkan method is simple to conduct but requires an operator to repeatedly pour known volumes of water through a ring positioned at the soil surface. A cheap infiltrometer equipped with a data acquisition system was recently designed to automate Beerkan infiltration experiments. In this paper, the current prototype of the automated infiltrometer was tested to validate its applicability to the Beerkan infiltration experiment under several experimental circumstances. In addition, t…
Multi-scale Modelling of Segmentation
2016
While listening to music, people often unwittingly break down musical pieces into constituent chunks such as verses and choruses. Music segmentation studies have suggested that some consensus regarding boundary perception exists, despite individual differences. However, neither the effects of experimental task (i.e., real-time vs. annotated segmentation), nor of musicianship on boundary perception are clear. Our study assesses musicianship effects and differences between segmentation tasks. We conducted a real-time experiment to collect segmentations by musicians and nonmusicians from nine musical pieces. In a second experiment on non-real-time segmentation, musicians indicated boundaries a…
A Space-Vector State Dynamic Model of the Synchronous Reluctance Motor Including Self and Cross-Saturation Effects and its Parameters Estimation
2018
This paper proposes a space-vector dynamic model of the Synchronous Reluctance Motor (SynRM) including both self-saturation and cross-saturation effects and selecting as state variables the stator currents. The proposed dynamic model is based on an original function between the stator flux and stator current components, and relies on 8 coefficients (fewer than other models in the scientific literature), presenting an interesting physical interpretation. Starting from this approach, both the static and dynamic inductances expressions of the model have been analytically developed, so that the reciprocity conditions for the cross saturation is satisfied. This paper presents also a technique fo…
State Estimation of a Nonlinear Unmanned Aerial Vehicle Model using an Extended Kalman Filter
2008
An Extended Kalman Filter is designed in order to estimate both state variables and wind velocity vector at the same time for a non conventional unmanned aircraft. The proposed observer uses few measurements, obtained by means of either conventional simple air data sensors or a low cost GPS. To cope with the low rate of the GPS with respect to the other sensors, the EKF algorithm has been modified to allow for a dual rate measurement model. State propagation is obtained by means of an accurate six degrees of freedom nonlinear model of the aircraft dynamics. To obtain joint estimation of state and disturbance, wind velocity components are included in the set of the state variables. Both stoc…
Descriptor-type Kalman Filter and TLS EXIN Speed Estimate for Sensorless Control of a Linear Induction Motor.
2014
This paper proposes a speed observer for linear induction motors (LIMs), which is composed of two parts: 1) a linear Kalman filter (KF) for the online estimation of the inductor currents and induced part flux linkage components; and 2) a speed estimator based on the total least squares (TLS) EXIN neuron. The TLS estimator receives as inputs the state variables, estimated by the KF, and provides as output the LIM linear speed, which is fed back to the KF and the control system. The KF is based on the classic space-vector model of the rotating induction machine. The end effects of the LIMs have been considered an uncertainty treated by the KF. The TLS EXIN neuron has been used to compute, in …