Linear quadratic Gaussian control of discrete-time Markov jump linear systems with horizon defined by stopping times

The linear quadratic Gaussian control of discrete-time Markov jump linear systems is addressed in this paper, first for state feedback, and also for dynamic output feedback using state estimation. in the model studied, the problem horizon is defined by a stopping time τ which represents either, the occurrence of a fix number N of failures or repairs (T N), or the occurrence of a crucial failure event (τ δ), after which the system paralyzed. From the constructive method used here a separation principle holds, and the solutions are given in terms of a Kalman filter and a state feedback sequence of controls. The control gains are obtained by recursions from a set of algebraic Riccati equations for the former case or by a coupled set of algebraic Riccati equation for the latter case. Copyright © 2005 IFAC.

Approximate controllability for the semilinear heat equation in RN involving gradient terms

We prove the approximate controllability of the semilinear heat equation in R^N, when the nonlinear term is globally Lipschitz and depends both on the state u and its spatial gradient Ñu. The approximate controllability is viewed as the limit of a sequence of optimal control problems. In order to avoid the difficulties related to the lack of compactness of the Sobolev embeddings, we work with the similarity variables and use weighted Sobolev spaces.

Existence of solutions for a class of degenerate quasilinear elliptic equation in R-N with vanishing potentials

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Multiplicity of solutions for a biharmonic equation with subcritical or critical growth

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vibrational-rotational analysis of supersingular plus quadratic A/r(4)+r(2) potential

Most work on supersingular potentials has focused on the study of the ground state. In this paper, a global analysis of the ground and excited states for the successive values of the orbital angular momentum of the supersingular plus quadratic potential is carried out, making use of centrifugal plus quadratic potential eigenfunction bases. First, the radially nodeless states are variationally analyzed for each value of the orbital angular momentum using the corresponding functions of the bases; the output includes the centrifugal and frequency parameters of the auxiliary potentials and their eigenfunction bases. In the second stage, these bases are used to construct the matrix representation of the Hamiltonian of the system, and from its diagonalization the energy eigenvalues and eigenvectors of the successive states are obtained. The systematics of the accuracy and convergence of the overall results are discussed with emphasis on the dependence on the intensity of the supersingular part of the potential and on the orbital angular momentum.

Geometric Integrability of the Camassa-Holm Equation. II

It is known that the Camassa–Holm (CH) equation describes pseudo-spherical surfaces and that therefore its integrability properties can be studied by geometrical means. In particular, the CH equation admits nonlocal symmetries of “pseudo-potential type”: the standard quadratic pseudo-potential associated with the geodesics of the pseudo-spherical surfaces determined by (generic) solutions to CH, allows us to construct a covering π of the equation manifold of CH on which nonlocal symmetries can be explicitly calculated. In this article, we present the Lie algebra of (first-order) nonlocal π-symmetries for the CH equation, and we show that this algebra contains a semidirect sum of the loop algebra over sl(2,R) and the centerless Virasoro algebra. As applications, we compute explicit solutions, we construct a Darboux transformation for the CH equation, and we recover its recursion operator. We also extend our results to the associated Camassa–Holm equation introduced by J. Schiff.

Kink stability, propagation, and length-scale competition in the periodically modulated sine-gordon equation

We have examined the dynamical behavior of the kink solutions of the one-dimensional sine-Gordon equation in the presence of a spatially periodic parametric perturbation. Our study clarifies and extends the currently available knowledge on this and related nonlinear problems in four directions. First, we present the results of a numerical simulation program that are not compatible with the existence of a radiative threshold predicted by earlier calculations. Second, we carry out a perturbative calculation that helps interpret those previous predictions, enabling us to understand in depth our numerical results. Third, we apply the collective coordinate formalism to this system and demonstrate numerically that it reproduces accurately the observed kink dynamics. Fourth, we report on the occurrence of length-scale competition in this system and show how it can be understood by means of linear stability analysis. Finally, we conclude by summarizing the general physical framework that arises from our study.

IDB and AFDF authorization : hearing before the Subcommittee on Foreign Assistance of the Committee on Foreign Relations, United States Senate, Ninety-fourth Congress, first session, on H.R. 9721 ... January 28, 1976.

Mode of access: Internet.

Hearings on H.R. 10451, Navy nuclear career incentive act, before the Subcommittee on Military Compensation of the Committee on Armed Services, House of Representatives, Ninety-fourth Congress, first session ...

Mode of access: Internet.

Amending Clayton Act by requiring prior notification of certain corporate mergers and for other purposes. Hearings, Eighty-fourth Congress, second session, on H.R. 6748, H.R. 7229, and H.R. 8332, bills to amend Clayton Act relating to mergers. January 16, 18, 20, 23, 1956.

"Serial No. 15"

National workers' compensation act of 1975 : hearings before the Subcommittee on Manpower, Compensation, and Health and Safety of the Committee on Education and Labor, House of Representatives, Ninety-fourth Congress, second session, on H.R. 9431 ....

Hearings held in Washington, D.C., Feb. 4-May 20, 1976; in Miami, Fla., Mar. 29 ; and in Meriden, Conn., Apr. 3, 1976.

1977 NASA authorization [microform] : index for hearings before the Committee on Science and Technology, House of Representatives, Ninety-fourth Congress, second session, on H.R. 11573 (superseded by H.R. 12453) ...

Reuse of record except for individual research requires license from Congressional Information Service, Inc.

Payment of interest on public demand deposits : hearings before the Committee on Banking, Housing and Urban Affairs, United States Senate, Ninety-fourth Congress, second session, on S. 3163 ... H.R. 3035 ... July 20 and 21, 1976.

Mode of access: Internet.

Federal farm loan act. Hearings before the Committee on banking and currency of the House of representatives, Sixty-seventh Congress, fourth session, on H.R. 13125 (as revised and numbered H.R. 14041) To amend sections 3, 4, 9, 12, 15, 21, 22, and 25 of the Act of Congress approved July 17, 1916, known as the Federal farm loan act. December 21, 1922; January 4, 5, 9, 10, 11, and 15, 1923 ....

Louis T. McFadden, chairman.