Abstract. Vibration fault diagnosis of hydroelectric unit was investigated using method of least square support vector machine (LS-SVM) and Dempster-Shafer theory (D-S Theory). Spectrum and amplitude characteristic was acted as eigenvector of learning samples to train the constructed LS-SVM regression and classifier for realizing mapping relationship between the fault and the characteristic. Information fusion was realized after completing local diagnosis, and then fault diagnosis was achieved. Experiments show that the method has a rapidly diagnostic process and generalization performances. It is suitable for the vibration fault diagnosis of hydroelectric unit.

This paper proposes a new single-end impedance based fault location method for power distribution systems. Based on direct three-phase circuit analysis, the authors have devised a generalized fault-location formulation in phase domain utilizing the fault admittance matrix. Newton-Raphson method is used for the solution of fault-location formulation. In order to eliminate the capacitive effect of feeders, the proposed algorithm adopts π model of line for the calculation of voltage and current in iterative process. The validity of the algorithm is tested with IEEE 34 Node Test Feeder using PSCAD-EMTDC. Simulation results have demonstrated that the method has high accuracy and good robustness.

On the basis of nonlinear features analysis of restoring torque, damping torque and especially hull deformation, a nonlinear roll equation of rotary-molded boats has been established. The equation includes elastic deformation term which makes the equation different from existing ones for steel boats. This paper dissected its dynamic characteristic of rolling motion from different aspects by using time domain diagram, phase graph, Poincare map, as well Lyapunov exponential spectrum. And then, an exact feedback linearization controller was designed using closed-loop gain shaping algorithm to make the boat get rid of chaotic state. Through numerical simulation, it is found that the roll frequency and velocity increase when elastic deformation occurs; i.e., the roll stability margin shrinks, and the chaos phenomenon is much more remarkable. This conclusion laid the foundation for controlling or restraining the boat's rolling and can be used as the basis of how to amend the evaluation criteria on rotarymolded boat stability.

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A fuzzy logic approach was proposed to regulate the number of vehicles entering a freeway entrance point during rush traffic times. The basic structure of a fuzzy logic controller was analyzed and the fuzzy control algorithm was formulated. The membership functions were developed and the fuzzy logic entrance ramp controller was designed based on such traffic information as the flow, speed, occupancy, and ramp queue length. These variables were each measured by several sensors built into the upstream, downstream, and entrance ramp portion of the freeway. Simulation research was carried out by taking full advantage of a computer. Simulation results show that such an approach is practical and effective. It can avoid traffic jams and congestion on the mainline, improve the passing capability, and make the vehicles travel more efficiently and safely.