This paper applies nonlinear 3t, control techniques to linear systems with actuator nonlinearities. In [3], this was treated under the certainty equivalence assumption. The control design produces a finite dimensional measurement feedback controller which is computable online provided certain conditions are met. In this paper, we do not use certainty equivalence theory. Instead, we use the more...

In this paper we address the problem of wave dynamics in presence of concentrated nonlinearities. Given a vector field V on an open subset of C and a discrete set Y ⊂ R with n elements, we define a nonlinear operator ∆V,Y on L (R) which coincides with the free Laplacian when restricted to regular functions vanishing at Y , and which reduces to the usual Laplacian with point interactions placed ...

This paper documents the dynamic properties of national output, its components, and the current account for five OECD countries. There is strong evidence of conditional volatility for almost all time series as well as significant deviations from normality. The deviations are detected particularly in GDP, net exports, investment time series. JEL Codes:

This paper describes a new gain scheduling algorithm for handeling the problem of hard nonlinearities like input rate and magnitude saturations. The proposed algorithm was originally designed for stabilization of integrator chains with input rate saturation. Here it is shown that the gain scheduler also is eeective for rudder roll control systems. The approach is to reduce the controller gains ...

The ability of photorefractive crystals such as barium titanate and strontium barium niobate to record spatially phase shifted real time holograms with high diffraction efficiency is the basis of many new optical devices involving coherent amplification. Some examples are unidirectional ring resonators, passive phase conjugate mirrors and coherent image amplifiers. 1 While in the past, most att...

In order to construct the border solutions for nonsupersingular elliptic curve equations, some common used models need to be adapted from linear treated cases for use in particular nonlinear cases. There are some approaches that conclude with these solutions. Optimization in this area means finding the majority of points on the elliptic curve and minimizing the time to compute the solution in c...

Dedicated to the memory of my mother Acknowledgments I would like to express my sincere appreciation to my adviser, Prof. Jonathan W. Pillow for his support and friendship throughout my Ph.D.. His enthusiasm deeply motivated me to push myself hard to become a competent research scientist. I would also like to thank my co-adviser, Prof. Alan C. I would also like to thank my family and my best fr...

This paper shows the existence of Lur’e-Postkinov Lyapunov functions for the generalized multivariable discrete-time Popov criterion. The nonlinearities in the Lur’e system considered here are monotonic, sectorand slope-restricted. We discuss the cases where the nonlinearities are diagonal and non-diagonal. Our derivation is based on the discrete-time Kalman-Yakubovich-Popov (KYP) lemma and the...

In this paper we deal with Robin and Neumann parametric elliptic equations driven by a nonhomogeneous differential operator and with a reaction that exhibits competing nonlinearities (concave-convex nonlinearities). For the Robin problem and without employing the Ambrosetti-Rabinowitz condition, we prove a bifurcation theorem for the positive solutions for small values of the parameter λ > 0. F...