Search results for "RESOLUTION"
showing 10 items of 1928 documents
ATLAS
2020
The book provides a comprehensive overview of high-resolution and high-definition anorectal manometry (HRAM/HDAM), showing the possible benefits of a wider use of these techniques in clinical practice, as well as their limitations. Although these techniques provide fresh insights into anorectal function and offer a new perspective on the pathophysiologic mechanisms of many defecation disturbances, there is a need to clarify whether their use has beneficial effects on clinical management compared to conventional manometry. There is still a considerable way to go to gain the clinical diffusion of esophageal HRM, which has become the gold standard in studying esophageal motility. Indeed, many …
Accretion shock on CTTSs and its X-ray emission
2009
High spectral resolution X-ray observations of classical T Tauri stars (CTTSs) demonstrate the presence of plasma at T~2-3×10^6 K and ne~10^11-10^13 cm-3. Stationary models suggest that this emission is due to shock-heated accreting material. We address this issue by a 1-D hydrodynamic model of the impact of the accretion flow onto a chromosphere of a CTTS with the aim of investigating the stability of accretion shock and the role of the chromosphere. Our simulations include the effects of gravity, radiative losses from optically thin plasma, the thermal conduction and a detailed modeling of the stellar chromosphere. Here we present the results of a simulation based on the parameters of the…
Estrategias emocionales en educación física a través del aprendizaje servicio: aplicación del programa siente jugando en alumnado de primaria
2019
Las emociones, la inteligencia emocional y la competencia socioemocional son algunos de los contenidos transversales que podemos desarrollar desde la Educación Física escolar. El juego motor es una fuente de estímulos y vivencias que favorece el desarrollo de las estructuras físicas y cerebrales que el alumnado de Primaria utilizará en su presente y futuro. El objeto de este estudio fue analizar las estrategias utilizadas para la resolución de conflictos tras la puesta en práctica de un programa de intervención denominado “Siente Jugando”, haciendo uso de la metodología Aprendizaje Servicio. La muestra estuvo formada por 93 participantes de Educación Primaria Obligatoria (EPO), de edades co…
Multi-temporal and Multi-source Remote Sensing Image Classification by Nonlinear Relative Normalization
2016
Remote sensing image classification exploiting multiple sensors is a very challenging problem: data from different modalities are affected by spectral distortions and mis-alignments of all kinds, and this hampers re-using models built for one image to be used successfully in other scenes. In order to adapt and transfer models across image acquisitions, one must be able to cope with datasets that are not co-registered, acquired under different illumination and atmospheric conditions, by different sensors, and with scarce ground references. Traditionally, methods based on histogram matching have been used. However, they fail when densities have very different shapes or when there is no corres…
Synergistic integration of optical and microwave satellite data for crop yield estimation
2019
Developing accurate models of crop stress, phenology and productivity is of paramount importance, given the increasing need of food. Earth observation (EO) remote sensing data provides a unique source of information to monitor crops in a temporally resolved and spatially explicit way. In this study, we propose the combination of multisensor (optical and microwave) remote sensing data for crop yield estimation and forecasting using two novel approaches. We first propose the lag between Enhanced Vegetation Index (EVI) derived from MODIS and Vegetation Optical Depth (VOD) derived from SMAP as a new joint metric combining the information from the two satellite sensors in a unique feature or des…
Interpolation and Gap Filling of Landsat Reflectance Time Series
2018
Products derived from a single multispectral sensor are hampered by a limited spatial, spectral or temporal resolutions. Image fusion in general and downscaling/blending in particular allow to combine different multiresolution datasets. We present here an optimal interpolation approach to generate smoothed and gap-free time series of Landsat reflectance data. We fuse MODIS (moderate-resolution imaging spectroradiometer) and Landsat data globally using the Google Earth Engine (GEE) platform. The optimal interpolator exploits GEE ability to ingest large amounts of data (Landsat climatologies) and uses simple linear operations that scale easily in the cloud. The approach shows very good result…
Intrapulmonary 3He Gas Distribution Depending on Bolus Size and Temporal Bolus Placement
2008
OBJECTIVE: Dynamic ventilation (3)He-MRI is a new method to assess pulmonary gas inflow. As differing airway diameters throughout the ventilatory cycle can influence gas inflow this study intends to investigate the influence of volume and timing of a He gas bolus with respect to the beginning of the tidal volume on inspiratory gas distribution. MATERIALS AND METHODS: An ultrafast 2-dimensional spoiled gradient echo sequence (temporal resolution 100 milliseconds) was used for dynamic ventilation (3)He-MRI of 11 anesthetized and mechanically ventilated pigs. The applied (3)He gas bolus was varied in volume between 100 and 200 mL. A 150-mL bolus was varied in its application time after the beg…
Improving the performance of acousto-optic tunable filters in imaging applications
2010
Acousto-optic tunable filters (AOTFs) can be used as spectral filters for the implementation of multispectral imaging systems. However, obtaining quality images is challenging. In this work, we propose several improvements that enable the use of these systems in quantitative spectroscopic imaging applications. The improvements are based on three pillars: 1. a finer spectral bandpass shaping by dynamically optimizing the radio frequency (rf) driving signal, 2. an extensive calibration process, and 3. careful image preprocessing that uses calibration data to correct some well known AOTF issues in imaging applications. A novel multispectral imaging instrument is built using commercial off-the-…
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…
Continuous Refocusing for Integral Microscopy with Fourier Plane Recording
2018
Integral or light field imaging is an attractive approach in microscopy, as it allows to capture 3D samples in just one shot and explore them later through changing the focus on particular depth planes of interest. However, it requires a compromise between spatial and angular resolution on the 2D sensor recording the microscopic images. A particular setting called Fourier Integral Microscope (FIMic) allows maximizing the spatial resolution for the cost of reducing the angular one. In this work, we propose a technique, which aims at reconstructing the continuous light field from sparse FIMic measurements, thus providing the functionality of continuous refocus on any arbitrary depth plane. Ou…