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The paper reviews the characteristics of geological disasters in Three Gorges reservoir area and the bandwidth of the communication lines, as well as the functions and the effects of emergency rescue system. The thesis briefly describes the target and content of the monitoring and prediction of the emergent geological disasters commanding platform, and also gives the data flow analysis of its subsystems emergency — commanding car, upon which the overall system block diagram design of the commanding car can be achieved. According to the mainly indexes of the system requirements, we analyze the functions of its sub-modules, and finally implement the system. The spot test shows that the design of this system is reliable, security and strong, of which the voice is clear, the images are smooth, the data transmission is stable.

The emergency command system is an important part in the project of warning, monitoring and geologic disasters prevention in the Three Gorges Reservoir Area, because it can provide a reliable technical guarantee. This paper describes a multimedia emergency command system based on satellite IP link. The characteristics include an on-the-spot information collection and transmission, an integrated emergency communications, an emergency commanding, an emergency dispatching and strategic decision analysis. The system can meet the need of emergency mobile command and is effective and practical. It enhances the efficiency of working for establishing interconnection of the discrete resources and realizing the commanding of emergency.

A blind audio watermarking algorithm in the time domain is proposed. The audio signal is divided into frames and the watermark is inserted on a frame by frame basis. The proposed algorithm detects the watermark using a signal processor based on the stochastic resonance mechanism. The watermark detection does not need the original audio. The parameter-induce stochastic resonance in audio watermarking is observed and the interpretation to this phenomenon is given. For the synchronization attack, the experimental results show that the stochastic resonance signal processor can catch up and surpass the performance of the matched filter. This reveals a robustness superiority of the stochastic resonance signal processor, compared to the matched filter operating outside its strict nominal conditions, which is especially helpful for the audio watermarking.

The paper addresses the noise image which adopts the embedded zerotree wavelet coding algorithm to compress and then results in decreasing the amount of the zerotree and increasing the amount of the alone-zero, which will affect the compression effect. Therefore this paper brings forward the characteristic directional median filter to reduce noise before the noise image compression; aim at solving the insufficiency of the scope table order frequent adjusts in the EZW algorithm, we proposes to adopt adaptive depth first search strategy through definition floating threshold. The result shows that the new image compression scheme has improved better than traditional EZW algorithm in the aspects of image quality, compression effect and compression coding efficiency.

Due to the problem of detecting weak signal in strong noise, a method of pulse signal detection was put forward which is based on multiresolution wavelet analysis. According to Parserval theorem, the frame of signal space decomposition and energy distributing was established by this method, and a complete orthogonal multi-resolution description is defined, the design of floating threshold of multiresolution wavelet analysis was discussed, and the removing noise algorithm has been given. The result of experiment and emulation shows that multi-band wavelet analysis is able to extract the weak and unclear pulse signal from white noise. This method is applied to laser pulse exploration system, and which has better effect.