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A phenomenon is defined as any state or process known through the senses rather than by intuition or reasoning, and thus is an observable event, especially something special or unusual. A geophysical phenomenon in the context of geoscience data can be characterized as a spatial region which is significantly different from the rest of the image; having higher/lower than average background intensity...
Reflectance pattern and spatial pattern characterize the geospatial data. Current semantic-enabled framework retrieval system extract primitive features based on color, texture (Spatial Gray Level Dependency - SGLD matrices), and shape from the segmented homogenous region. This system can use only three bands (true color or false color) at a time to capture color information as it converts RGB space...
Geospatial content-based image retrieval (CBIR) systems can be used to query for visually similar images by identifying similar patterns between a query image and those in the database. When several different classes of features are used, some queries require that each class should be given a different degree of weight; to this end, CBIR indexes are built for each class of features. This paper proposes...
After the great success of the Tropical Rainfall Measuring Mission (TRMM), Global Precipitation Measurement (GPM) started as an international mission and follow-on mission of the TRMM project to obtain more accurate and frequent observations of precipitation. The accurate measurement of precipitation will be achieved by the DPR installed on the GPM core satellite. In order to estimate accurate precipitation...
Assessments on the performance of dual-frequency (13.6/35.5 GHz) precipitation radar (DPR) rain retrieval techniques are performed through simple vertical rain profiles synthesized with arbitrarily defined and disdrometer-measured raindrop size distribution (DSD) data. A DPR inversion technique (DPR-IT) with the estimates of differential attenuation (DA), which used to resolve the path-integrated...
Radar polarimetry radar Interferometry and polarimetric SAR interferometry represent the current culmination in 'microwave remote sensing' technology, but we still need to progress very considerably in order to reach the limits of physical realizability. Whereas with radar polarimetry the textural fine-structure, target orientation, symmetries and material constituents can be recovered with considerable...
Entropy, alpha and anisotropy (H/alpha/A) of the polarimetric target decomposition of Cloude and Pettier has been an effective and popular tool for polarimetric SAR image analysis and geophysical parameter estimation. However, multi-look processing can severely affect the values of these parameters. In this paper, a Monte Carlo method is used to evaluate the multi- look effect on these parameters...
The presence of speckle noise in Synthetic Aperture Radar images prevents a correct interpretation, as well as, the information retrieval processes. It has been recently demonstrated that speckle noise may introduce biases into the retrieved physical information when multidimensional data is considered. In case of multidimensional SAR systems, for single-look data, it has been proved that speckle...
This paper analyzes the worsening effects the sea surface can induce on vessel classification algorithms working with SAR imagery. Two issues will be tackled, the complex motion history of ships and the polarimetric scattering mechanisms generated by the sea-hull interaction. Both can modify the information that allows to infer the geometry of ships dropping the classification capability. The current...
In this paper, a study of the temporal evolution of the elements of 3 x 3 covariance matrix using an X-band polarimetric ground-based SAR sensor is proposed. Although the heterogeneity of the scenario allows to select different target typologies, the study is mainly focused on the analysis of azimuthally symmetric distributed targets. The fluctuations of the most representative elements of [C] as...
The elephant-in-the-room: It's so obvious, why didn't we see it before? In the context of "dual-polarized radar", especially Earth-observing synthetic aperture radar, the elephant is simply the relative phase between the two image outputs of a "dual-polarized" SAR. Capture the elephant-which for certain systems may be a minimal-cost transformation-to realize nearly a dozen quantitative...
Selective application of herbicide in agricultural cropping systems provides both economic and environmental benefits. Implementation of this technology requires knowledge of the location and density of weed species within a crop. In this study, two image classification techniques (neural networks and maximum likelihood) are compared for accuracy in weed/crop species discrimination. In the summer...
In this paper, we propose a new scheme to extrapolate wavelet features with respect to the resolution. By explicitly taking into account the acquisition process of satellite images, we compute how wavelet features behave when the resolution changes. This approach is validated by classifying satellite images with different resolutions.
This paper shows how to obtain a binary change map from similarity measures of the local statistics of images before and after a disaster. The decision process is achieved by the use of a zz-SVM in which a stochastic kernel has been defined. Stochastic kernel includes two similarity measures, based on the local statistics, to detect changes from the images: 1) A distance between maginal probability...
In this paper are described some enhancements for a straightforward method recently developed by the authors for evaluating post flood damages using Landsat TM/ETM+ data integrated with digital terrain models (DTMs) and based on the principal components transform (PCT). In particular, the main updates refer to the computational scheme in deriving the flood extension map with the use of the minimum...
A series of Landsat TM, ETM and radar data were used to establish land cover and flood risk maps as a function of land cover in Bac-Hung-Hai region in Northern Vietnam. Land cover in one key parameter which has an influence on the occurrence of inundation in that region. Both spectral and textural features were considered in order to improve land cover classification. The radar data was used to reduce...
Many features of interest in remote sensing imagery, such as roads, rivers, clouds, trees, and buildings can have high spectral, structural, and textural variability due to variations in reflectance, resolution, intrinsic shape, etc. Nevertheless they have distinctive qualitative properties of their own from the point of human perception. For instance, clouds are typically fluffy or wispy, roads have...
After reviewing and discussing the difficulties of dealing with automatic interpretation methods in SAR imagery, the advantages of using a multiscale time-frequency framework will be established. Then, a specific technique for automatic spot detection, based on the Wavelet Transform (WT), will be presented and justified. The performance of the proposed algorithm will be tested, validated and compared...
The limiting factor to the use of Frequency Modulated Continuous Wave (FMCW) technology with Synthetic Aperture Radar (SAR) techniques to produce lightweight, cost effective, low power consuming imaging sensors with high resolution, is the well known presence of non-linearities in the transmitted signal. This results in contrast and range resolution degradation, especially when the system use is intended...
One example of an application of EOS science data is the computation of aerodynamic roughness for momentum and its ultimate application to meteorological and atmospheric transport modeling. Currently, data products derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and other sensors such as Landsat and ASTER are being used to estimate vegetation and urban (non-vegetated) aerodynamic...
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