A5072888687- Synthetic Aperture Radar (SAR) Applications and Techniques
- Soil Moisture and Remote Sensing
- Cryospheric studies and observations
- Arctic and Antarctic ice dynamics
- Geophysical Methods and Applications
- Precipitation Measurement and Analysis
- Climate change and permafrost
- Structural Health Monitoring Techniques
- Landslides and related hazards
- Data-Driven Disease Surveillance
- Geography and Environmental Studies
- Public Relations and Crisis Communication
- Rock Mechanics and Modeling
- Indoor and Outdoor Localization Technologies
- Dam Engineering and Safety
- Geophysics and Gravity Measurements
- Seismology and Earthquake Studies
- Big Data Technologies and Applications
- Image and Object Detection Techniques
University of Lisbon
2011-2020
National Laboratory for Civil Engineering
2014
Lusíada University of Lisbon
2011
Abstract In this work we present a methodology for the mapping of Snow Water Equivalent (SWE) temporal variations based on Synthetic Aperture Radar (SAR) Interferometry technique and Sentinel-1 data. The shift in interferometric phase caused by refraction microwave signal penetrating snow layer is isolated exploited to generate maps variation SWE from coherent SAR interferograms. main advantage proposed with respect those inversion backscattering models its simplicity reduced number required...
In this work, we exploit the integration of an advanced synthetic aperture radar (SAR) interferometry technique and application finite-element method for assessment interpretation a localized subsidence phenomenon that took place within specific area Lisbon, Portugal. SAR images over Lisbon city, covering different time intervals in period 1995-2010, were acquired processed by means persistent scatterers (PSs) technique. Results clearly reveals subsidence, limited to 2 km × 1.5 wide, which...
The safety control and structural analysis of Portuguese large dams has been using, for many decades, small triangulation networks to monitor the horizontal displacements a carefully selected set target points on dams. recent surge in use motorised tacheometers, which enable automatic measurement angles distances, is changing traditional into combined angles/distances networks. This paper addresses estimation weights adjustment distances.
The increase of social media use in recent years has shown potential also for the identification specific trends data that could be used to locate earthquakes. In this work, we implemented a pipeline uses Twitter identify locations earthquakes and information trigger EO analysis. We tested almost year over Japan, an area where earthquake events are frequent, as well population. Here, show results discuss development such procedures. future, considering rapid satellite constellations aimed at...
Synthetic Aperture Radar (SAR) interferometry is currently providing displacement measurements over large areas and recently also maps of water vapor in atmosphere. However, the interferometric phase can capture tiny contributions due to soil moisture. In this work results obtained a 1-year experiment with in-situ moisture agricultural area, flat land around Tagus river, Lisbon, Portugal, are presented. We analyze two models for estimation from SAR images. Sentinel-1 images C-band used their...
In this work we present the results of an experiment aiming to measure a ground subsidence in city Lisbon, Portugal, possibly related works for building city's subway infrastructure. A time series 46 ERS SAR images, acquired between May 1995 and January 2001, is interferometrically processed using Persistent Scatterers (PS) technique terrain deformation velocities estimated at location PS. The interferometric (InSAR) estimates are compared topographic measurements carried out 1976, 1996 2010.
In this work we study the problem of mapping soil moisture by means Synthetic Aperture Radar (SAR) images. A test site has been set in Companhia das Lezirias, close to Lisbon, Portugal. The main advantage using SAR images is their capability map at a very high spatial resolution. This opens interesting perspectives for agricultural applications, where can abruptly change across field boundaries depending on practices. area characterized flat topography, large areas and sparse vegetation....
In this paper we summarize the results of an experiment aiming to compare soil moisture estimates obtained by Sentinel-l interferometric data with in-situ measurements. The study area, located close Lisbon in Companhia das Lezirias, Portugal is characterized a flat topography, large agricultural areas and sparse vegetation. test site, four sensors were deployed was measured (at depth 5 cm) for period 7 months hourly basis. For same interval time temporal resolution 6 days C-band SAR images...
<p>We have recently investigated the use of SAR interferometry for mapping Snow Water Equivalent (SWE) temporal variations using Sentinel-1 data [1]. Maps changes SWE, measured with a sub-centimetre accuracy and updated every six days been obtained over study area in Finland. This methodology relies on shift interferometric phase caused by refraction microwave signal penetrating snow layer. In this work, we investigate inconsistencies [2] sets three interferograms from images...