Search results for "Mach"
showing 10 items of 3360 documents
A Cloud masking algorithm for the XBAER aerosol retrieval using MERIS data
2017
Abstract To determine aerosol optical thickness, AOT, and other geophysical parameters describing conditions in the atmosphere and at the earth's surface by inversion of remote sensing measurements from space based instrumentation, it is necessary to separate ground scenes into cloud free and cloudy or cloud contaminated. Identifying the presence of cloud in a ground scene and establishing an accurate and adequate cloud mask is a challenging task. In this study, measurements by the European Space Agency (ESA) MEdium Resolution Imaging Spectrometer (MERIS) have been used to develop a cloud identification and cloud mask algorithm for preprocessing prior to application of the new algorithm cal…
Global Sensitivity Analysis of Leaf-Canopy-Atmosphere RTMs: Implications for Biophysical Variables Retrieval from Top-of-Atmosphere Radiance Data.
2019
Knowledge of key variables driving the top of the atmosphere (TOA) radiance over a vegetated surface is an important step to derive biophysical variables from TOA radiance data, e.g., as observed by an optical satellite. Coupled leaf-canopy-atmosphere Radiative Transfer Models (RTMs) allow linking vegetation variables directly to the at-sensor TOA radiance measured. Global Sensitivity Analysis (GSA) of RTMs enables the computation of the total contribution of each input variable to the output variance. We determined the impacts of the leaf-canopy-atmosphere variables into TOA radiance using the GSA to gain insights into retrievable variables. The leaf and canopy RTM PROSAIL was coupled with…
Comparing methods for computation of run-up heights of landslide-generated tsunami in the Northern Sicily continental margin
2018
The North Sicily continental margin is a very active region located in the Central Mediterranean. Strong seismicity, active tectonics and volcanism, fluid escape, high sediment supply, and widespread mass movements historically have exposed this region to marine geohazards, with a potential for tsunami generation. Morpho-bathymetric analysis revealed that one of the most common mechanisms associated with marine geohazards is due to submarine mass failure processes, genetically linked to the other processes active in this margin. With the aim to assess the risks associated with landslide-generated anomalous waves, we selected two sectors of this margin, Gulf of Palermo to the west and Patti …
Entorno 3D para el análisis y la recreación virtual de las actuaciones arqueológicas en Cueva de la Cocina (Dos Aguas, Valencia, España)
2017
Con este trabajo pretendemos presentar nuestro procedimiento de digitalización de información de campo (gestión de datos) y su imbricación en la reconstrucción estratigráfica virtual (virtualización) de la Cueva de la Cocina (Dos Aguas, Valencia, España). La herramienta principal para la implementación del Sistema de Información Geográfica (SIG) ha sido OpenJUMP, mientras que para la recreación tridimensional (3D) del entorno virtual de la cueva se han utilizado MeshLab, ParaView, CloudCompare y R. De acuerdo con los datos recuperados durante las excavaciones de los últimos años en la cueva -2015 y 2016-, se presenta el estado actual de la virtualización de la estratigrafía en los sectores …
Systematic revision of the Late Miocene sabre-toothed felid Paramachaerodus in Spain
2010
Abstract: A systematic revision of the sabre-toothed cat genus Paramachaerodus Pilgrim, 1913 is presented. Two species are recognized within Paramachaerodus, Pa. orientalis, and Pa. maximiliani, and the genus Promegantereon Kretzoi, 1938 is retrieved to include Promegantereon ogygia. Material from the Turolian Spanish localities of Crevillente-2 (MN 11, Alicante) and Las Casiones (MN 13, Teruel), which was previously assigned to Paramachaerodus, is now included in the tribe Metailurini. The exceptional discoveries at the Spanish Vallesian (MN 10, Madrid) fossil site of Batallones-1 have made it possible to characterize the dentition and cranial anatomy of a previously very poorly known mac…
Cannibalism facilitates gigantism in a nine-spined stickleback (Pungitius pungitius) population
2016
Cannibalism is a taxonomically widespread phenomenon that can fundamentally affect the structure and stability of aquatic communities, including the emergence of a bimodal size distribution (“dwarfs” and “giants”) in fish populations. Emergence of giants could also be driven or facilitated by parasites that divert host resources from reproduction to growth. We studied the trophic ecology of giant nine-spined sticklebacks (Pungitius pungitius) in a Finnish pond to evaluate the hypotheses that gigantism in this population would be facilitated by cannibalism and/or parasitic infections by Schistocephalus pungitii cestode. Stomach content analyses revealed an initial ontogenetic dietary shift f…
Potential use of machine learning methods in assessment of Fusarium culmorum and Fusariumproliferatum growth and mycotoxin production in treatments w…
2021
Abstract The use of Fusarium-controlling fungicides is necessary to limit crop loss. Little is known about the effect of commercial antifungal formulations at sub-lethal doses, and their interaction with abiotic factors, on Fusarium culmorum and F. proliferatum development and on zearalenone and fumonisin biosynthesis, respectively. In the present study different treatments based on sulfur, trifloxystrobin and demethylation inhibitor fungicides (cyproconazole, tebuconazole and prothioconazole) under different environmental conditions, in Maize Extract Medium (MEM), are assayed in vitro. Then, several machine learning methods (neural networks, random forest and extreme gradient boosted trees…
Evaluation of image processing technique as an expert system in mulberry fruit grading based on ripeness level using artificial neural networks (ANNs…
2020
Abstract Image processing and artificial intelligence (AI) techniques have been applied to analyze, evaluate and classify mulberry fruit according to their ripeness (unripe, ripe, and overripe). A total of 577 mulberries were graded by an expert and the images were captured by an imaging system. Then, the geometrical properties, color, and texture characteristics of each segmented mulberry was extracted using two feature reduction methods: Correlation-based Feature Selection subset (CFS) and Consistency subset (CONS). Artificial Neural Networks (ANN) and Support Vector Machine (SVM) were applied to classify mulberry fruit. ANN classification with the CFS subset feature extraction method res…
Resource polymorphism in European whitefish: Analysis of fatty acid profiles provides more detailed evidence than traditional methods alone
2019
Published version, licensed CC BY-NC-ND 4.0. , available at: http://dx.doi.org/10.1371/journal.pone.0221338 Resource polymorphism—whereby ancestral generalist populations give rise to several specialised morphs along a resource gradient—is common where species colonise newly formed ecosystems. This phenomenon is particularly well documented in freshwater fish populations inhabiting postglacial lakes formed at the end of the last ice age. However, knowledge on how such differential exploitation of resources across contrasting habitats might be reflected in the biochemical compositions of diverging populations is still limited, though such patterns might be expected. Here, we aimed to assess …
Calibrating Expert Assessments Using Hierarchical Gaussian Process Models
2020
Expert assessments are routinely used to inform management and other decision making. However, often these assessments contain considerable biases and uncertainties for which reason they should be calibrated if possible. Moreover, coherently combining multiple expert assessments into one estimate poses a long-standing problem in statistics since modeling expert knowledge is often difficult. Here, we present a hierarchical Bayesian model for expert calibration in a task of estimating a continuous univariate parameter. The model allows experts' biases to vary as a function of the true value of the parameter and according to the expert's background. We follow the fully Bayesian approach (the s…