Scientific Research Publishing

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52827#.VKn7FsnQrzE Author(s)   Baishun Liu * Affiliation(s) Academy of Naval Submarine, Qingdao, China . ABSTRACT This paper proposes two kinds of nonlinear general integral controllers, that is, one is generic and another is practical, for a class of uncertain nonlinear system. By extending equal ratio gain technique to a canonical interval system matrix and using Lyapunov method, theorems to ensure regionally as well as semi-globally asymptotic stability are established in terms of some bounded information. Moreover, for the practical nonlinear integral controller, a real time method to evaluate the equal ratio coefficient ...

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52211#.VIj4jsnQrzF Author(s) Ankita Sharma * , A. J. Shaiju Affiliation(s) Department of Mathematics, Indian Institute of Technology Madras, Chennai, India . ABSTRACT In this article, affine-quadratic control problems are studied. Error bounds are derived for the difference between the performance indices corresponding to the optimal and a class of suboptimal controls. In particular, it is shown that the performance of these suboptimal controls is close to that of the optimal control whenever the error in estimating the costate initial condition is small. KEYWORDS Affi...