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Taking advantage of the hyperbolic characteristics of the telegrapher equations, this paper applies the Lax-Wendroff technique, usually used in fluid dynamics, to transmission line analysis. A second-order-accurate Lax-Wendroff difference scheme for the telegrapher equations for both uniform and nonuniform transmission lines is derived. Based on this scheme, a new method for analyzing lossy multiconductor transmission lines which do not need to be decoupled is presented by combining with matrix operations. Using numerical experiments, the proposed method is compared with the characteristic method, the fast Fourier transform (FFT) approach, and the Lax-Friedrichs technique. With the presented method, a circuit including lossy multiconductor transmission lines is analyzed and the results are consistent with those of PSPICE. The nonlinear circuit including nonuniform lossy multiconductor transmission lines is also computed and the results are verified by HSPICE. The proposed method can be conveniently applied to either linear or nonlinear circuits which include general transmission lines, and is proved to be efficient.

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Adjusting the agricultural planting structure is one of the important means to realize agricultural water-saving, especially in arid inland river basin. In this paper, taking Shiyang River Basin as an example, on the basis of determining the crop water production function, a multi-objective optimization model was constructed, which comprehensively considered the maximization of economic benefits, the green water utilization rate and ecological benefits. The optimized planting structure was obtained by using GAMS (General Algebraic Modeling System) model solver. The results showed that: The common features of the three level years after optimization is that the sown area proportion of wheat, tubers, vegetables, fruits and cotton all increased, of which the sown area of fruits increased most by 5.30 × 10 4 ha. However, the sown area proportion of corn and oil-bearing crops decreased, of which the sown area of corn decreased most by 8.90 × 10 4 ha. Comparing of three level years, it is found that the impact of climate change on planting structure adjustment was relatively weak. With the decrease of precipitation, it is suggested to slightly decrease the sown area of wheat but slightly increase the sown area of tubers. The optimization results of planting structure were different in different counties. The average contribution rate of planting structure adjustment to total water-saving was 73.32%, indicating that planting structure adjustment was the key to water-saving. The water consumption of the same crop was different in different counties.