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The lack of availability of historical and reliable river water level information is an issue that can be overcome through the exploitation of modern satellite remote sensing systems. This research has the objective of contributing in solving the information-gap problem of river flow monitoring through a synthetic aperture radar (SAR) signal processing technique that has the capability to perform water flow elevation estimation. This paper proposes the application of a new method for the design of a robust procedure to track over the time double-bounce reflections from bridges crossing rivers to measure the gap space existing between the river surface and bridges. Specifically, the difference in position between the single and double bounce is suitably measured over the time. Simulated and satellite temporal series of SAR data from COSMO-SkyMed data are compared to the ground measurements recorded for three gauges sites over the Po and Tiber Rivers, Italy. The obtained performance indices confirm the effectiveness of the method in the estimation of water level also in narrow or ungauged rivers.

The lack of availability of historical and reliable river water level information is an issue that can be overcome through the exploitation of modern satellite remote sensing systems. This research has the objective of contributing in solving the information-gap problem of river flow monitoring through a synthetic aperture radar (SAR) signal processing technique that has the capability to perform water flow elevation estimation. This paper proposes the application of a new method for the design of a robust procedure to track over the time double-bounce reflections from bridges crossing rivers to measure the gap space existing between the river surface and bridges. Specifically, the difference in position between the single and double bounce is suitably measured over the time. Simulated and satellite temporal series of SAR data from COSMO-SkyMed data are compared to the ground measurements recorded for three gauges sites over the Po and Tiber Rivers, Italy. The obtained performance indices confirm the effectiveness of the method in the estimation of water level also in narrow or ungauged rivers.

We obtained accurate, detailed motion distribution of glaciers in Central Asia by applying digital elevation model (DEM) assisted pixel-tracking method to L-band synthetic aperture radar imagery. The paper firstly introduces and analyzes each component of the offset field briefly, and then describes the method used to efficiently and precisely compensate the topography-related offset caused by the large spatial baseline and rugged terrain with the help of DEM. The results indicate that the rugged topography not only forms the complex shapes of glaciers, but also affects the glacier velocity estimation, especially with large spatial baseline. The maximum velocity, 0.85 m∙d−1, was observed in the middle part on the Fedchenko Glacier, which is the world’s longest mountain glacier. The motion fluctuation on its main trunk is apparently influenced by mass flowing in from tributaries, as well as angles between tributaries and the main stream. The approach presented in this paper was proved to be highly appropriate for monitoring glacier motion and will provide valuable sensitive indicators of current and future climate change for environmental analysis.

Bare PWB test systems require an exhaustive TP (test point) list to process the test operation. As not all CAD and CAM users talk to each other using intelligent data transfer, test information is usually lost. This is true as most systems today support only the Gerber format. Smart CAM tools have thus been developed to extract test information. The TP research is based on Gerber flashes. Software puts a TP everywhere a flash is plotted. Unfortunately, over 50% of SMT pads are drawn and not flashed due to their small width or because they represent network extremities. The current solution is to manually reconvert drawn pads to flashes before TP extraction. On one hand, the software is unreliable, while on the other, the intervention of an operator can inconvenience the exhaustive TP list generation and is in any case time consuming and expensive. TIMA laboratory and IMD Test Systems Div. have developed an alternative: new software based on image processing and pattern recognition to automatically extract full test data, including the netlist. In essence, this software converts the Gerber file to a bitmap image, and then does an intelligent vectorization by tracking net by net (a net is an object of connected pixels) while running pattern recognition to extract TPs. The main advantages of this original method are that tracking connected pixels on the bitmap avoids the mistakes of vectorial calculations (nets are always correct) and the software is not limited by drawn pads as it does not use flash information (no need to convert draws to flashes). Test data are thus complete and the netlist is correct.