Huangnishan hill is located in the southern area of Nantong City,Jiangsu Province. In this paper,we studied magnetic and granulometric characteristics of loess deposits from the Huangnishan hill and the origin of loess. The sediments are dominated by silty clay,and finer than those of both the Xiashu loess in Zhenjiang and the loess in the Chinese Loess Plateau. Huangnishan loess is similar to Xiashu loess in magnetic property,implying that the Huangnishan loess is the same as the Xiashu loess in Zhenjiang area,which is of aeolian origin. The fluctuation of magnetic parameters indicates that paleoenvironmental changes were recorded in the loess,too. The lower content of fine-grained ferrimagnetic minerals and higher S-100 values of the deposits in comparison to the Xiashu loess suggest that the Huangnishan loess experienced a lower degree of pedogenic alteration than that of the Xiashu loess in Zhenjiang.
The paper presents a design technique using adaptive backstepping method for the aircraft longitudinal flight path control laws. This control method constructs the Lyapunov function using backstepping loops, and designs on-line GCMAC neural networks used to study and compensate the unknown aerodynamic uncertainties in the plant model. Then, the neural network weights turn laws are designed based on Lyapunov approach, which guarantee the states tracking error of the nonlinear system and the approximation errors of neural network converge to zero. This control method is used to design the flight path angle control system and aircraft longitudinal automatic landing control system which only consider gliding and leveling phase. The simulation results show that the adaptive backstepping controller has a good tracking performance and robustness.
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