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To solve the problem of high computational complexity and real-time poor of the SIFT(Scale Invariant Feature Transform) algorithm, a parallel data streams RGF-SIFT(Recursive Gaussian Filter-SIFT) algorithm based on DSP multi-core processor is proposed. The proposed algorithm uses the forth-order recursive Gaussian filter to replace the linear Gaussian filtering of the SIFT algorithm. Then the four modules of RGF-SIFT computing tasks are assigned to multiple DSP core for parallel processing, and implemented synchronization for multicore processor through inter-processor communication (IPC) and other technologies. Experimental results show that the parallel RGF-SIFT algorithm detects feature point more than the algorithm of SIFT, and the repetition rate of the correct feature point is very high. At execution time, the parallel RGF-SIFT algorithm has higher speedup ratio.

This paper analyze the choice on organizational form of business model from three different perspectives. The transaction cost theory perspective pays attention to ‘behavior uncertainty’ while the core competence perspective analyzes the ‘demand uncertainty’ and the real options theory perspective focuses on ‘capacity uncertainty’. The decision maker should synthesize these three different perspectives to make the right decision.

A feedback canceller model was built to cancel the feedback interference which caused by the coupling paths between the antennas of the transmitter and receiver in on-channel repeater. The normalized delay least square mean algorithm was presented to improve the capability of feedback canceller. The improved method could not only cancel echo signal in a low processing delay when relaying, but also get a fast convergence rate and better maladjustment performance. With this algorithm, on-channel repeater may be applied in many wireless broadcasting systems with different guard intervals. Simulation results show that, when the antenna isolation is lower than the gain of repeater, the improved feedback canceller could eliminate the multi-path echo signal to an allowable level, and it could increase the antenna isolation above 20dB.