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The tsunami disaster triggered by a huge 9.0 magnitude earthquake strikes Japan on March 11th, 2011. It motivates us to get involved in a research work in tsunami topics of Taiwan and to simulate an impact of the tsunami on the coast of Taiwan. Tsunami propagation is often modeled by the shallow water equations. These equations are derived from conservation of mass and momentum equations. By adding...
Malaysia situated within the buffer zone of the Pacific Ring of Fire, is vulnerable to seismic hazards as a result of the prevalence of geodynamic activities in Southeast Asia within the past decade particularly since the 8.9 Mw Megathrust in 2004. Prolonged plates activities have been resulting in the on-land lineament along the mid-ridges of the peninsular since the Paleozoic period. In this study,...
Fourier techniques are often used in radar imaging and feature extraction of ISAR data. One drawback is the appearance of artifacts due to scatterer interactions within the target. This paper defines a modified bicoherence, based on a specific target scattering model, to distinguish target scattering centers from target interactions and develop target-specific features for identification. Third-order...
A technique combined CFAR and EF detection method is presented to improve the power transmission tower detection in synthetic aperture radar (SAR) image. CFAR can detect power transmission tower as the point like targets used the intensity information. EF features is sensitive to target geometric feature, which can consider the shape of power transmission tower. The paper takes advantage of intensity...
Collection of ground truth to validate remote sensing classification and/or detection algorithms is rarely accounted for due to the inaccessibility of the sites or the elevated costs of such operations. In this paper some of the opportunities behind crowd-sourcing are explored through the description of a remote sensing project on water quality monitoring in Africa where the ground truth was collected...
In this paper, we use the MODIS thermal anomaly product (hotspots data) to study the temporal and spatial patterns of vegetation fires in the western part of Insular Southeast Asia for a decade from 2001 to 2010. Fire occurrence exhibits a negative correlation with rainfall, and is more severe overall during the El-Nino periods. However, not all regions are equally affected by El-Nino. In Southern...
Validation of AMSR-E soil moisture product (AE_Land3) over densely vegetated areas in a tropical region (Peninsular Malaysia) has been conducted in this study. The daily AE_Land3 soil moisture product at 25km spatial scale were compared with the ground data over a period of 2 years (2008 and 2009), collected at Pasoh Forest Reserve (PSO), Malaysia. The validation was built separately on the relationship...
Due to the active collision between Eurasian and Philippine Sea tectonic plates, the rocks of Taiwan are highly fractured and vulnerable to slope failures. In addition, Taiwan lies in the track of severe tropical cyclones known in East Asia as typhoons. Deep-seated landslides caused by heavy rainfall are usually catastrophic. One of the most catastrophic disaster is Hsiaolin Slide triggered by typhoon...
Northwest Himalaya is one of the seismically most active regions of the world. For seismic hazard assessment, it is important to calculate the seismicity parameters for every source zones. Homogenous earthquake catalog is a basic input for seismic hazard calculation. General orthogonal regression relation is used to convert different magnitude scales into a single moment magnitude scale. Declustering...
In this paper we present a radio technique for detecting and measuring the extent of hydraulic fractures in subsurface rock layers using MF band. The method is based on transmission measurements among elements of vertical and horizontal arrays in the borehole before and after fracking process. To realize this system a novel super-miniaturized borehole antenna operating at 2MHz is also presented. The...
GPR imaging often uses contours of constant wave travel time or electrical path length to determine possible locations of buried targets. The intersection points of two contours triangulates the target. If the GPR is above the ground, rays from the source refract at the ground interface as they enter the ground, and as such yield non-intuitive loci of constant travel time. A simple method is presented...
The unsteadiness of the low altitude platforms leads to uneven light and shade in the azimuth of synthetic aperture radar (SAR) images. The traditional method for the azimuth intensity adjusting of SAR images has two important disadvantages. The first is its discontinuity of the normalization factor, and the second is its inapplicability on regions with broken terra of very weak or very strong back...
The HyperSpectral Imager for Climate Science (HySICS) is a spatial/spectral spectrometer for viewing Earth scenes with the ∼0.2% (1-σ) radiometric accuracy needed for climate studies. Covering the reflected solar spectral region from 350 to 2300 nm with 6 nm resolution, this instrument will provide 0.5 km spatial resolution while covering a 100 km ground swath from low Earth orbit. A single focal...
Aboveground (AG)-biomass was estimated from a field biomass collection and LiDAR observations for a natural forest in Indonesia. The derived AG-biomass data were plotted against full polarimetric parameters calculated from Polarimetric and Interferometric Airborne Synthetic Aperture Radar L2 (Pi-SAR-L2) and PALSAR data. The α°-AG-biomass curve shows saturation by around 100 tons/ha, while for entropy,...
We presents a new method for retrieving tropical cyclone vector winds using C-band dual-polarization SAR observations. The co-polarized geophysical model function (CMOD5.N) and a cross-polarized wind speed retrieval model for dual-polarization (C-2POD) are employed to construct a cost function. minimization of the cost function allows optimum estimates for the wind speeds and directions. The wind...
In this paper, a new way of integration of SAR geometric correction and radiometric rectification named radar-coding method has been put forward for the improvement of accuracy and efficiency in SAR image classification in glacierized district. A radar-coding look up table has been constructed based on geometric correction, which can be used for generating the simulated SAR. Then radiometric rectification...
Snow water equivalent have been retrieved from passive microwave instruments for many decades. Current SWE products from NSIDC and GlobSnow are achievements of traditional spectral difference method and newly developed assimilation algorithm combining model estimates with ground-based weather station data. In this paper, validation analysis show that GlobSnow SWE possess less RSM errors in each month...
The paper considers the detection of beetle infestations in North American pine forests using high temporal resolution, coarse spatial resolution MODIS remotely sensed satellite images. Two methods are proposed to detect beetle infestation, both applying a triply modulated cosine model. The first method uses an Extended Kalman Filter (EKF) for estimating model parameters, and the second a Least Squares...
Spectral mixture analysis is an important technique to extract desired information from the mixed remotely sensed data. However, current spectral mixture analysis techniques suffered from the endmember variability. Quantitative assessment of SMA techniques with simulated data is critical to understand the influence of endmember variability. For that reason, this study has compared five typical spectral...
In this research, we propose an unsupervised change detection methodology for synthetic aperture radar (SAR) images. By analyzing the goodness of fit, it is found that pixels in no change area in the change image generated by normalized difference ratio (NDR) operator better fit with normal distribution. Based on this assumption, we identify the pixel range that fits the normal distribution better...
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