| Satellitic thermal infrared remote sensing has become a promising technique for monitoring fault activities and earthquake precursors for its many advantages, such as a wide field of vision, high spatial resolution, short observation period, and also owing to its good reflection to thermal infrared anomalies of some major earthquakes. However, the thermal thermal infrared radiation of the earth’s surface is influenced by the external non-seismic factors, such as cloud layers, terrain, object styles, and weathe. All the non-seismic factors cannot be excluded only with the satellite data in a period around the earthquake. A general research on the historic satellite data of at least two years using temporal and spatial compositive analysis of statistics is of great necessity to find out the universal features. For seismic thermal infrared remote sensing, the time resolution of the geostationary satellite is higher than that of the polar-orbiting satellite (a panorama graph which covers about 1/3 of the whole earth can be captured each half hour during the flood season or each hour during the non-flood season), which is favorable to generating short period and high quality brightness temperature data over all the surface of China and capturing the earthquake precursor information. Nevertheless, the lack of the seismology oriented extensive satellite data processing system and a massive professional data warehouse needed by seismologists has seriously restricted the research. The observation and application technology with satellitic thermal infrared remote sensing has been listed in the medium- and long-term program for the development of science and technology in China and the plans for earthquake prevention and disaster reduction. Moreover, the satellitic thermal infrared remote sensing, the ground application system, the technology for processing the space-earth Integration observation data, and the means for recognizing and extracting the seismic information have been listed in the program for the development of seismic science and technology published by the five ministries and commissions as an important field to develop and a prior research subject.A meteorological satellite receiving system has been established since August 2007, and the satellite data received everyday is up to 3G. Hence, about 1000G original data will be received every year which are a large database in addition with 3TB original data received from January 2006 to August 2007. The workload would be extensive if these data were preprocessed in receiving, correcting, backup, and generating images for specific purposes only by manual guard, so it is difficult to ensure the timeliness and reliability of satellite data. This thesis suggests for a model of calibrating the differences of the surface brightness temperature of the geostationary satellite generated by time zone differences, the algorithm of short-period eliminating cloud, the precision orientation algorithm of geostationary satellite image, and resolves the problems of automated noise and cloud elimination, data correction, encoding, decoding and geo-info processing. The studies include processing algorithms, researching, developing and applying the means for processing the geostationary satellite data. Based on the researches, a quasi-real time satellite data auto-processing system has been developed and through the operation of the system, a massive cloud-eliminated database and a suited imagery info database have been set up, containing data from 2006 up to the present.The quality of the thermal infrared surface brightness temperature data has been the first limitation to the research of seismicity by thermal infrared anomalies. The first important problem to be solved is the noise and interference lines to the original data during the application of automated processing. Aiming at this, this thesis researches and develops the algorithm of automated recognizing and eliminating noise and interfering lines. The second problom is the interference of the cloud layer. If the earth surface is covered by the cloud layer, the thermal infrared information probed by the satellite will be the information of the cloud layer instead of the earth surface. At present, the main means for eliminating the interference of the cloud layer is to compare and analyze the multi-temporal graphs of the same region during a period (e.g. 10 days). Assuming that a region has the weather of cloudless during this period, the image of this period can be used as a part to generate a composite image. For the polar-orbiting satellite used for seismic thermal infrared monitoring, only two-night images (with a remote possibility of three images)for the same region in China one day can be used because of its long revisiting period (the revisiting period is 24 hour for a single satellite). So it will take 10 days to synthesize a large area cloud-eliminated land surface Brightness temperature image,such as the whole China area(for the same receiving point), but hardly including the western region(because the elevation angle of the receiving antenna is small ). Meanwhile, a fewer images for some local areas for pixel comparing lead to the lower quality of cloud-eliminated synthetic image. Thus the consecutive national synthetic land surface brightness temperature images with high quality and a short period are hard to be made. Based on the characters of high time resolution and broad covering scope of the geostationary satellite, this work makes use of the pixel of a larger NE value to replace the pixel of of a smaller NE value according the 2nd thermal channel with the satellite data between 0:00 and 3:00 a.m. every 3-5 days (the influences from sun elevation angle, relative azimuth angle, sunshine and cooling down time are generally the same), and realize the concrete algorithm. The result shows that it is better to synthesize a cloud-eliminated image with every 5 days’satellite data. For the thermal infrared channels, although they are in an atmosphere window, the atmosphere effects still exist(mainly presented as the water absorption), so as to weak the thermal infrared radiation energy received by the satellite sensor. The thesis inverses land surface brightness temperature with the total 211 images at 4:00 a.m. from September 18, 2007 to August 15, 2008 in 9 regions by the split-window method. The result of inversion shows that the atmospheric effects on land surface brightness temperature are about -12~8K. The database of land surface brightness temperature in the mainland of China and adjacent areas is obtained by the above method.The thesis realizes the transparent gateway with double-export-link based on the Netfilter/Iptables technique according to the need of data sharing system and remote computing, and thus improves visit speed to sharing center of the earthquake geological and seismic dynamics data and reduces network congestion. The new idea of the ArcIMS and. NET Platform integrated development programmes by the use of ArcIMS Servlet Connector connectors is put forward. The advantages are as follows: 1. It retains the development mode of using ArcIMS Servlet Connector; 2. The Asp.net server powerful functionality is integrated into make the user achieve a higher value analysis and calculation; 3. It greatly enhances the development efficiency. The thesis realizes the distributed remote sensing image release and sharing system on the basis of WebGIS according this solution based on the data warehouse formed by the geostationary satellite automatic processing system.With the developments of information technology, it becomes possible to obtain the magnanimity seismic observation data of high precision, digitization and network. It is the intensively rich Earth’s information which promotes earthquake prediction research and Earth science research. By using the modern network information technology, the observation systems, scientific computing systems, database systems and infrastructure resources are connected and shared with each other. The information technology environment of network real-time collaborative study, experiment instrument remote use and resource sharing formed by building the modern earthquake network computing application and network scientific environment platform will enhance scientific and technological innovation capability of earth sciences and earthquake prediction efforts. It is also a part of the national network technology environment and provides information and experiences for its construction. Based on the framework of the state earthquake network computing application system, relying on the network remote computing sub node of Institute of Geology, and daily running of the near-real time processing system of geostationary satellite which is developed independently by ourselves, the thesis builds a data warehouse covering historical magnanimity data, a center of data exchange and data services, and designs the integration framework of Web Service and WebGIS system, develops a remote computing service system for geostationary satellite brightness temperature field and realizes the computing model and computing applications of brightness temperature field of any region for the network client. With the above research, the observation systems, scientific computing systems, database systems and infrastructure resources are connected and shared with each other.The primary research results are of this work as follows:(1) It realized the quasi-real time processing system of geostationary satellite with independent intellectual property rights by developing from the bottom with Vc++ platform, and effectively improved the data quality of thermal infrared land surface brightness temperature by realizing the automatic de-noising algorithm, the short-period synthesis eliminating cloud algorithm and the precision orientation algorithm of geostationary satellite image.(2)It realized the brightness temperature field of geostationary satellite remote computing service, developed the algorithm of extracting brightness temperature data of dynamic area, and provided the computing model and applications of brightness temperature field of any region for the network client by designing the integration framework of Web Service and WebGIS system. The current more mature Web Service and grid computing were preliminarily integrated.(3) A model of calibrating the differences of the brightness temperature of geostationary satellite generated by time zone differences is suggested for the first time. A total of 16 curves of four positions in four different stages are given through sample statistics of brightness temperature of every 5 days synthetic data which are from four different time zones. The above four stages are made of January -March (Winter), April-June (Spring), July-September (Summer), October-December (Autumn). Three kinds of correct situations and correct formulas based on curves change are able to better eliminate brightness temperature rising or dropping caused by time zone differences.(4) It gained the brightness temperature changing along with time evolution and spatial distribution through studying on the brightness temperature of 9 monitoring areas data from 2006 to 2008 with data warehouse concept and statistical methods. It presents case study on the earthquake in Yutian, Xinjiang. The result shows that the brightness temperature value at the Kangxiwa fault nearly the epicenter began to increase 35 days before the event. Eight days prior to the shock, this value became much higher than the surroundings, reaching maximum 263.36K 7 days before the event. And 4 hours to the seismic occurrence, this value tended to decline. After the earthquake, it continued to drop by about 4K. The average value of 2008 is 1.1-6.84K higher than 2006 and 3.8-14.2K higher than 2007 in the same period 25 days prior to the shock.(5) The observation systems, scientific computing systems, database systems and infrastructure resources are connected and shared with each other, by establishing technology environment and platform of seismic network computing applications, and researching how the quasi-real time processing system of geostationary satellite, the remote sensing image release system based on WebGIS, and the remote computing service system cooperate with each other. |
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