Fu Maosheng

A new texture image segmentation algorithm

The relations between synthesis technology and image fusion are generalized, and some key questions are analyzed when using quotient space granularity synthesis in image segmentation. Furthermore the granularity synthesis method of quotient space is applied to analyze and processing of texture images and a new image segmentation algorithm of image segmentation is given. Firstly texture features of coarseness and directionality are extracted to form the different granularity spaces respectively. Then the quotient space synthesis method is adopted to segment the texture image. Experimental results demonstrate that the algorithm of granularity synthesis is useful and valid.

Three-phase four-leg inverter based on current positive feedback control

The power quality of grids has been influenced by the mounting number of asymmetric loads. Recently, the three-phase four-leg inverter which adds a bridge to three-phase three-bridge inverter has been researched because of the merit of the compact structure, small bulk and high efficiency. The three-phase four-leg inverter has subsequently brought vigor into the power system with broad application prospects but its control method becomes much more complex than ever and difficult to achieve. Therefore, a new control method has been proposed in this paper based on positive feedback of current control and three-dimensional space vector modulation (SVM). Through analyzing the four-leg inverter system, three-phase unbalanced current is introduced from the three-phase voltage feedback control. Furthermore, the amount of imbalance is increased through positive feedback in order to control the balanceness of three-phase output voltage more quickly and accurately. The simulation showed the feasibility and effectiveness of the method proposed in this paper.