Large reservoirs along rivers regulate downstream flows to generate hydropower but may also store water for irrigation and urban sectors. Reservoir management therefore becomes critical, particularly for transboundary basins, where coordination between riparian countries is needed. Reservoir management is even more important in semiarid regions where downstream water users may be totally reliant on upstream reservoir releases. If the water resources are shared between upstream and downstream countries, potentially opposite interests arise as is the case in the Syrdarya river in Central Asia. In this case study, remote sensing data (radar altimetry and optical imagery) are used to highlight the potential of satellite data to monitor water resources: water height, areal extent and storage variations. New results from 20 years of monitoring using satellites over the Syrdarya basin are presented. The accuracy of satellite data is 0.6 km 3 using a combination of MODIS data and satellite altimetry, and only 0.2 km 3 with Landsat images representing 2-4% of average annual reservoir volume variations in the reservoirs in the Syrdarya basin. With future missions such as Sentinel-3A (S3A), Sentinel-3B (S3B) and surface water and ocean topography (SWOT), significant improvement is expected. The SWOT mission's main payload (a radar interferometer in Ka band) will furthermore provide 2D maps of water height, reservoirs, lakes, rivers and floodplains, with a temporal resolution of 21 days. At the global scale, the SWOT mission will cover reservoirs with areal extents greater than 250 × 250 m with 20 cm accuracy.

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Vertical InGaN multiple quantum wells light-emitting diodes (LEDs) with through-holes structure were transferred from Si(111) substrate onto the electroplating copper submount successfully. The additional series resistances induced by the AlN buffer layer and other interlayer were shorted by the metals filled through-holes. The LED with through-hole structure shows a low vertical conducting operating voltage and a small series resistance. Combining with substrate removal and copper electroplating technique, the operating voltage at 350 mA and series resistances of the LED were reduce from 5.6 to 5.1 V and 7 to 4 , in comparison with through-hole LED before substrate removal. At the same time, the light output intensity was improved by 75%, which was mainly attributed to both the removal of light absorptive substrate and the substitution for highly thermal conductive copper submount with metal reflector. #

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