In the 36th World Conference on Space Science, Wuhan University of Surveying and Mapping State Key Laboratory of Remote Sensing Information Engineering Director, Chinese academicians Deren pointed out that satellite navigation and positioning data processing is relatively mature in automated, intelligent and real-time,data communications, real-time wide area differential GPS and other technology to meter-scale accuracy of spatial orientation, and even a centimeter decimeters.America's GPS performance is improved through the upgrade, the European Union is redoubling its efforts to promote the 30 satellites of the Galileo program, China's second-generation navigation systems will be 12 satellites, on a wider geographical provide real-time satellite navigation and positioning servicesI hope 2020 can be built into a similar independent global navigation positioning system.
Li Deren introduced, formed in the eighties and nineties of the last century of geo-spatial information science, the future direction of the "four modernizations", that space-time access to information integration and globalization on the world, processing and handling automation, intelligent and real-timetechnology, management and distribution of grid and service popularity.This earth observation satellite technology development and a higher requirement.
Photogrammetry and Remote Sensing as an authoritative scientist, Li Deren 80 years since the last century played a major error in measurement theory and treatment research; first test after the variance estimates derived from the gross errors in electoral power iteration method, called the international measurement of academic"Deren method."He pointed out that in order to 3S technologies, global positioning system (GPS), geographic information systems (GIS), remote sensing (RS) as the representative, including communication technology, computer technology, including new discipline - geospatial information science, geographic information isan important part of science, the basis for Digital Earth.
"Meteorological satellites, oceanic satellites, land resources satellites, mapping satellites, on the form, features varying on the effective use of Earth observation satellites can help people effectively solve the ever growing population, resources, environment and natural disasters and other issues."Deren said.
It is understood that China's vast population, land resources survey, land protection and land-use change detection is a very important regular work.Since the reform and opening up, who spent 10 years had a large 1:1 million land use survey.At present, mainly rely on high-resolution (2 meters to 10 meters) of satellite images and 3S, in the "Eleventh Five-Year" for the second largest national land survey, and the establishment of China's "digital territory"; space flight on the 250meter resolution "of Resolution Imaging Spectrometer" (MODIS) and 1-km resolution, "improved very high resolution radiometer" (AVHRR) remote sensing data, due to the high time resolution can be used to produce standardized vegetationIndex (NDVI), for land cover change and crop growth monitoring.Annual 2 m to 10 m resolution optical satellite images using image fusion techniques can be used to change the annual land survey.
Earth observation technology in China will be used for many years forest fires, droughts and floods, ice flood / sea ice such as early warning and disaster prevention, urban mountain landslide and subsidence monitoring, vegetation changes, urban expansion of the research, as well as urban and rural planningto promote national economic development and improvement of living standards.In recent years, China's use of aerial remote sensing for environmental monitoring of the application of several tests, the environmental quality of cities and pollution levels were analyzed and evaluated, including the urban heat island, smoke spread, water pollution, green cover index and the trafficsuch as monitoring, have achieved important results.
Remote sensing data are very useful in disaster prevention.Li Deren, China's flood disaster in the calendar year, the Canadian RadarSat satellite and the European ERS1 / 2, ASAR satellite data and reflect the annual water level of the optical image, rapid delineation of flooded areas.He pointed out that the use of nine major river basins of the digital elevation model data, can flood simulation and analysis; use of MODIS and other moderate-resolution satellite images, can the drought, the Yellow and Bohai Bay in the ice for real-time disaster monitoring; 1 km resolutionrate of meteorological satellites, can provide 20 minutes to 1 hour per satellite images to monitor the occurrence of dust storms and spread out.In addition, the possibility of using satellite remote sensing thermal infrared images observed temperature anomalies before earthquakes earthquake prediction is still a research value of complex issues.