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In this paper, the tracking control problem of a class of fuzzy approximation-based noncanonical nonlinear systems with hysteresis inputs is investigated, where the fuzzy weight matrix is not available for measurement, and the hysteresis nonlinearities are modeled by the Prandtl–Ishlinskii operator. Due to the coupling effects, the plant input containing hysteresis is unknown. To solve the problem, two adaptive control schemes are developed. The first is a Lyapunov-based scheme, and the second is a gradient-based scheme. For convenience, only the relative-degree-one case is taken into account in design and analysis. With the proposed schemes, it can be proved that all signals in the closed-loop system are bounded, and the tracking error converges to a small region around zero. Simulation results show that the maximum steady-state error converges to [ − 0.0131 , 0.0183 ] μ m and [ − 0.0139 , 0.0161 ] μ m with two control schemes, which confirms the obtained results. [ABSTRACT FROM AUTHOR]

Background: The oligophagous potato tuber moth (PTM), Phthorimaea operculella, and the polyphagous beet armyworm (BAW), Spodoptera exigua, are two destructive pests of potato, and infestations can lead to serious reduction in potato yield. However, potato plant responses to the two herbivories are only poorly understood. Endogenous jasmonoyl‐isoleucine (JA‐Ile) is a signal responsible for the induction of plant anti‐herbivore defenses. Elevation of JA‐Ile by blocking its catabolism is considered to be an effective and sustainable approach to enhance plant resistance to insect pests. However, it is not clear whether this approach can enhance potato resistance to PTM and BAW. Results: We demonstrated that the transcriptional changes induced by simulated PTM and BAW feeding overlap to a large extent, and that 81.5% of the PTM‐ and 90.5% of the BAW‐responsive genes were commonly regulated. We also generated potato transgenic lines, irStCYP94B3s, in which the three JA‐Ile hydroxylases were all simultaneously silenced. These lines exhibited enhanced resistance only to BAW, but not to PTM, although levels of JA‐Ile and its downstream induced defensive chemicals, including caffeoylputrescine, dicaffeoylspermidine, lyciumoside II, and the nicotianosides I, II, and VII, were all present at higher levels in PTM‐infested than in BAW‐infested irStCYP94B3s lines. Conclusion: Our results provide support for the hypothesis that StCYP94B3 genes are able to act as potential targets for the control of polyphagous insect pests in potato, and reveal that the oligophagous PTM has evolved an effective mechanism to cope with JA‐Ile‐induced anti‐herbivore defenses. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this paper, a new tuning function backstepping control scheme is proposed for a class of parametric strict feedback nonlinear systems to accommodate actuator failures/faults and dead-zone constraints, where the failures/faults are uncertain in time, pattern, and values, and the dead-zone parameters are not available. Roughly speaking, such a scheme is developed in two steps below. First, by using an adaptive smooth inverse function to compensate for the dead-zone nonlinearity, we separate the coupling actuator dynamics into two parts, i.e., the dead-zone compensation errors and the nominal failure dynamics. Afterward, we further handle these two parts based on the techniques of robust adaptive approach and parametrization method. With our scheme, the global boundedness of the signals in the closed-loop system are ensured, and the tracking error is steered to zero asymptotically. These results have also been verified through simulation studies.