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In this paper, a numerical model is set up to solve the mild slope equation proposed by Berkhoff using the finite element method. The computational result of wave run-up on a single non-submerged vertical cylinder matches well with the analytical solution, verifying the validity of the numerical model. The effect of the spacing between two cylinders on wave run-up is discussed. The results show that the position of maximum and minimum wave run-up on the upstream cylinder is almost the same with that of a single cylinder, but when the spacing is odd or even times of one quarter of incident wavelength, the secondary maximum or minimum wave run-up appears at the both sides of the cylinder. The curves of wave run-up on the downstream cylinder is similar but smaller than that of a single cylinder.

The chaotic characteristics of time series of five partial discharge (PD) patterns in oil-paper insulation are studied. The results verify obvious chaotic characteristic of the time series of discharge signals and the fact that PD is a chaotic process. These time series have distinctive features, and the chaotic attractors obtained from time series differed greatly from each other by shapes in the phase space, so they could be used to qualitatively identify the PD patterns. The phase space parameters are selected, then the chaotic characteristic quantities can be extracted. These quantities could quantificationally characterize the PD patterns. The effects on pattern recognition of PRPD and CAPD are compared by using the neural network of radial basis function. The results show that both of the two recognition methods work well and have their respective advantages. Then, both the statistical operators under PRPD mode and the chaotic characteristic quantities under CAPD mode are selected comprehensively as the input vectors of neural network, and the PD pattern recognition accuracy is thereby greatly improved.

The continuous test on oil impregnated pressboard insulation with internal void defect was developed and the phase resolved partial discharge (PRPD) pattern of partial discharge (PD) signals during the electrical aging process was measured. Two different void structures which have different void volume were used in this experiment. It shows that the PD pattern could be classified into five stages and a great diversity in the first four stages is observed. The larger void volume leads to larger PD magnitude. The computer numerical simulation model which is based on a physical discharge process was used and the causes of PD pattern change were interpreted by comparison with computer numerical simulation results. The initial values and change tendency of gas pressure and surface conductivity were determined through experiment. The model parameters in different stages have been studied as well as the insight into the physical changes in the void during electrical aging. The results provide rules for the identification of the electrical aging stage through the partial discharge measurements.

The wave coupling theory with analytic solution for mutual action of optical activity and Pockels effect in birefringent crystals is developed, which is based on Maxwell's equations and the second-order polarizations responsible for the two effects. We take the crystalline quartz as an example to demonstrate the applications of the theory and some typical results for different propagation directions and different external electric fields are presented. Besides, we find out the directions of pure electro-optic delay in the optically active crystals belonging to different point groups. Along these directions both the optical activity and electro-optic coupling are absent. These will facilitate the use of an optically active medium as an electro-optic modulator.

Previous studies of Alfven wave heating which employed kinetic theory are extended in order to take into account antenna configurations, in cylindrical geometry, consisting of arbitrary shell currents and their associated radial feeders. For each Fourier component of the form exp [-i(lζ-mθ)], the shell current consists of a divergence-free part having the helicity of the mode (l, m), plus an orthogonal part requiring the feeders. It is shown, both analytically and by including the full current in the numerical code, that only the divergence-free part of the current contributes significantly to the plasma response and antenna loading. The important effect of the feeders is to cancel the contribution from the surface current perpendicular to the helicity. This explicitly verifies results reported previously.