In this paper, a robust adaptive finite-time (FT) tracking control scheme is proposed for Euler-Lagrange systems (ELSs) subject to nonparametric uncertainties, unknown disturbances and input saturation. In the design procedure, a Gaussian error function is utilized to approximate the input saturation nonlinearity. Following that, by employing the natural property that the upper bound of model parameters uncertainties is linear-in-parameters, the lumped uncertain term that caused by uncertain model parameters and external disturbances is formulated by a linear-parametric form with a single parameter. And then, a novel robust adaptive tracking control law is designed to resolve the tracking control problem of uncertain ELSs. The proposed control scheme is featured by FT convergence rate, and robustness against uncertainties and unknown disturbances. Furthermore, the robust adaptive FT tracking control scheme is insensitive to the character of the uncertainties, and is with low computational burden and easy to implement in engineering applications. And its rigorous stability is analyzed with the aid of the Lyapunov stability theory, and its effectiveness is verified by simulation results and comparison.

No abstract

No abstract

A facile and simple method has been developed for the condensation of 1,2-diaminobenzenes with α-bromoketones to form quinoxalines with good yields using cetyltrimethyl ammonium bromide (CTAB) in aqueous media. The efficiency of this reaction was demonstrated by the compatibility with nitro, methyl, methoxy, fluoro chloro bromo and furanyl groups. The important features of the methodology are broad substrate scope, simple workup, and no requirement for metal catalysts.