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For real-time simulation of wave and its three-dimensional characteristics, an effective method is presented. Firstly, the LOD quadtree method is taken for high-precision grid drawing and improved Gerstner model is used for water height field modeling. Secondly, use P-M spectral theory to determine the upper and lower waves frequency limits. Then solve amplitude with integration method and extend it to arbitrary spectral sampling. Finally, after determine waveform parameter based on wave spectrum, we realize simulation of high-precision and large scale dynamic of real-time ocean waves.

For the complexity of the ship feature classification and sensitivity of optical sensor to weather, airspace, illumination and other marine environment, we propose a new unsupervised multi-ship image segmentation algorithm of remote sensing platforms, including separation from the target area of the adaptive multi threshold criterion, algorithm based on multiscale Ncut hierarchical, multi-objective analysis of ship motion. Finally, through verification and analysis by experiment, comparing with other relevant segmentation methods, our method has better robustness and recognition effect.

Wave simulation is the key technology in building model library of virtual combat platforms at sea, which directly affect the fidelity and feasibility. we firstly analyze regular waves model simulation. Then discuss the simulation of irregular waves and its three-dimensional generation algorithm using linear wave superposition method and wave spectrum theory. Through establishment of the sea regular grid and calling the OpenGL library, We reach the simulation results and provide a technical solution for virtual maritime combat platforms.

A stable long-distance quantum key distribution system which has been just completed in our laboratory is demonstrated in this paper. The idea of “plug and pl ay" was adopted to automatically compensate the polarization mode dispersion and phase shift. A symmetrical capacitance-balance technique and magic-T network were used in the single-photon detection module, wherein a detection efficiency of more than 5% and a dark count probability of lower than 29×10-6/p ulse were achieved. As a result, we have realized stable (longer than 12 h) quantum k ey distribution experiment in 506 km single mode fiber with mean photon number of 007 and quantum bit error rate of 4%.