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Wood vinegar is formed by the condensation of smoke produced during the production of biochar. It mainly contains acetic acid, butyric acid, catechol, and phenol. Wood vinegar has a compound effect of promoting crop growth similar to plant growth regulators and is environmentally friendly. Moreover, it can enhance the biological and abiotic resistance of crops. In this study, foliar spraying was carried out systematically in the field with the hybrid variety of Huayouza 9 for two years to study the effects of wood vinegar and its compounds on the growth of rapeseed (Brassica napus L.). We applied four treatments with tap water as a control (CK), namely wood vinegar diluted 400-fold (M), M mixed with gibberellin (T1), M mixed with sodium D-gluconate (T2), and M mixed with melatonin (T3). They were sprayed in the seedling stage and overwintering stage, respectively. The results showed that the seed yield, the leaf area index, and the number of pods per plant of rapeseed treated with M increased by an average of 9.58%, 23.45%, and 23.80% in two years as compared to the CK, respectively. Compared with M, the seed yield of rapeseed treated with T1, T2, and T3 increased by an average of 7.88%, 6.90%, and 1.32% in two years, respectively. The treatments also improved the quality of rapeseed. In particular, the glucosinolate content of rapeseed treated with T2 and T3 decreased by an average of 12.83% and 6.72% in two years compared to the CK, respectively. The four treatments selected in the current study improved the resistance of rapeseed at the low temperature of 2–6 °C by increasing the activity of superoxide dismutase and proline and soluble protein contents, as compared to the CK. Besides, all treatments containing M reduced the incidence of Sclerotinia sclerotiorum and Peronospora parasitica (downy mildew) in rapeseed. More specifically, the T3 treatment significantly decreased the infection rate of these two diseases mentioned above by an average of 17.33% and 12.14% in two years compared to the CK, respectively. Therefore, the study and application of wood vinegar due to its compound effects on crop growth and yield is of great importance to sustainable agriculture, crop ecology, and environmental protection.

In this paper, a novel adaptive fault-tolerant slidingmode control scheme is proposed for high-speed trains, where the longitudinal dynamical model is focused, and the disturbances and actuator faults are considered. Considering the disturbances in traction force generated by the traction system, a dynamic model with actuator uncertainties modelled as input distribution matrix uncertainty is established. Then, a new sliding-mode controller with design conditions is proposed for the healthy train system, which can drive the tracking error dynamical system to a pre-designed sliding surface in finite time and maintain the sliding motion on it thereafter. In order to deal with the actuator uncertainties and unknown faults simultaneously, the adaptive technique is combined with the fault-tolerant slidingmode control design together to guarantee that the asymptotical convergence of the tracking errors is achieved. Furthermore, the proposed adaptive fault-tolerant sliding-mode control scheme is extended to the cases of the actuator uncertainties with unknown bounds and the unparameterized actuator faults. Finally, case studies on a real train dynamic model are presented to explain the developed fault-tolerant control scheme. Simulation results show the effectiveness and feasibility of the proposed method.Index Terms-Actuator faults, fault-tolerant sliding-mode control, adaptive control, actuator uncertainty, high-speed train.

This paper considers incipient sensor fault detection issue for a class of nonlinear systems with "observer unmatched" uncertainties. A particular fault detection sliding mode observer is designed for the augmented system formed by the original system and incipient sensor faults. The designed parameters are obtained using LMI and line filter techniques to guarantee that the generated residuals are robust to uncertainties and that sliding motion is not destroyed by faults. Then, three levels of novel adaptive thresholds are proposed based on the reduced order sliding mode dynamics, which effectively improve incipient sensor faults detectability. Case study of on the traction system in China Railway High-speed is presented to demonstrate the effectiveness of the proposed incipient senor faults detection schemes.

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This paper proposes a design method of robust fault reconstruction for a 3‐DOF helicopter with actuator faults and disturbance. The model of the 3‐DOF helicopter considered in this paper is an affine nonlinear system. An adaptive sliding mode observer is firstly proposed such that the actuator fault can be reconstructed through the adaptive law online. Then, based on linear matrix inequalities (LMI), a feasible algorithm is explored to solve the designed parameters. Finally, a simulation study of the 3‐DOF helicopter is presented to show the effectiveness of the scheme.