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Aiming at the non-linearity and uncertainty of patient spastic disturbance in the trajectory tracking control of upper limb rehabilitation robot, an iterative learning control algorithm is proposed based on RBF neural network. This paper considers repetitive nature of the rehabilitation robot system, the algorithm combines a single hidden layer feedforward neural network with iterative learning. In the upper limb rehabilitation process, the algorithm accelerate the convergence speed of the trajectory tracking error, and quickly suppress the interference in the interference environment. The Lyapunov stability theory is used to prove the globally asymptotic stability of the closed-loop system, then simulation proves the feasibility and effectiveness of the proposed algorithm.

Due to hostile and rigorous environment, the copper pipe is subject to pits occurring on the external surface of the pipe. It is crucial and highly demanded to noninvasively detect and evaluate this flaw which has posed a severe threat to integrity of copper pipes. In light of the advantages of gradient-field pulsed eddy current technique (GPEC), this paper intensively investigates the detection and evaluation of subsurface pits in copper pipes via GPEC. A GPEC probe consisting of a bobbin-type excitation coil and array of magnetic sensors has been proposed for efficient pipe inspection. A new feature extracted from the differential signal of gradient-field is utilized for localization and assessment of pits distributing circumferentially and axially. Through a series of experiments, it can be found that the subsurface pit of ixQ.imm2 in diameterxdepth can be localized and quantitatively evaluated by using GPEC which is also found advantageous over conventional pulsed eddy current technique (PEC) in terms of higher efficiency and sensitivity to subsurface pits in copper pipes.

Based on analysis of the two main deficiencies of the current evaluation methods of carbonic acid erosion of groundwater to the concrete in China: a), the carbonic acid erosion indexes [CO2]s of different water samples have no comparability with each other; b). It is difficult to draw carbonic acid erosion partitioning map, a universal 'discriminant of groundwater' was deduced in this article. By employing special compiled 'calculation procedure of discriminant of carbonic acid erosion', not only calculation of the newly defined 'discriminant of carbonic acid erosion' has been completed, but also the calculation of carbonic acid erosion indexes [CO2]s by artificial table checking and interpolation in the past has been realized in computer. With the help of the discriminant and the calculation procedure proposed in this paper, not only horizontal comparison of the carbonic acid erosion between water samples is feasible, but also the partitioning map of the carbonic acid erosion can be compiled quantitatively. Furthermore, the two main deficiencies of the current evaluation method and the feasibility of drawing carbonic acid erosion partitioning map quantitatively by the discriminant in this paper the are shown in cases.