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It is very important to level foundation bed by riprap in water and soil engineering. In this paper, a real-time feedback convergence control method is proposed to control the position and heading angle of the riprap leveling ship. The wind, wave, current and hydrodynamic parameters are obtained by empirical formula; the tension of four cables is calculated according to the balance equation of six degrees of freedom, and then the cable deformation is obtained. According to the deformation of the cable, the length of the cable in a certain equilibrium state can be obtained. The length of four cables can be lengthened or shortened by comparing the length of cables at two balanced positions. The length of cables can be controlled by winch to complete the anchoring and positioning control of leveling ship.

Based on projection twin support vector machine (PTSVM) and its extensions, this paper describes an updated PTSVM (UPTSVM) for classification. Compared with existing PTSVMs, UPTSVM has its own advantages. First, similar to the standard support vector machine (SVM), UPTSVM maintains the consistency of the optimization problems in the linear and nonlinear case, which results in the nonlinear formulations can be directly turned into the linear ones. Nevertheless, the existing PTSVMs lose the consistency because of using empirical kernel to construct nonlinear formulations. Second, UPTSVM avoids the inverse of kernel matrixes in the course of solving dual problems, which indicates it can not only reduce computing time but also save storage space. Third, UPTSVM can be practically proved equivalent to the PTSVM with regularization (RPTSVM). Experimental results on lots of data sets show the virtue of the presented method.