Showing papers in "Systems & Control Letters in 1981"

TL;DR: In this paper, a notion of structurally fixed modes is introduced in the framework of decentralized control systems to identify the modes that cannot be shifted by decentralized feedback regardless of the numerical values of system parameters.

TL;DR: In this paper, necessary and sufficient conditions for various types of stochastic controllability of the linear system of the form d x = Ax d t + Bu d t+ C d w r, x(0) = x 0 are given.

TL;DR: In this article, an observer which can estimate a linear function of the state of the system is proposed for the purpose of implementing a feedback control law, and the relation between the observer and the Smith predictor is also discussed.

TL;DR: In this article, the definition of symmetries and conservation laws for autonomous (i.e. without external (cases) Hamiltonian systems are generalized to Hamiltonian system with inputs and outputs).

TL;DR: In this article, the authors show how in the particular case of diagonal compensators or similarity transforms, there is a very easy way, based on Perron-Frobenius theory, of obtaining optimal reduction in the off-diagonal elements.

TL;DR: Conditions for the existence of (f,g) invariant distributions in nonlinear systems and a procedure for the construction of the corresponding feedback control law is given in this article, where the authors also consider the problem of feedback control.

TL;DR: In this article, it was shown that a dynamical system which is unobservable with respect to any sample program consisting of 1 n samples does not necessarily have a small perturbation of the dynamics and does not destroy the nonobservability.

TL;DR: This work gives a graph-theoretic characterization of structured systems, which generically can be decoupled into single-input, single-output systems by state feedback.

TL;DR: In this article, the Cauchy problem of stochastic partial differential equations considered in nonlinear filtering problems is studied and the main result is the existence, uniqueness and exact formula of the solution in case the elliptic operator appearing in the equation is degenerate.

TL;DR: In this article, the finite escape of Riccati differential equations is studied and it is shown that periodic solutions, if they exist, are ither always finite or always infinite.

TL;DR: A new class of variable structure feedback systems capable of rejecting a persistent disturbance is developed which has structure similar to the linear multivariable servomechanism.

TL;DR: In this article, the conditions of overall deterministic stability of the adaptive control schemes which may be obtained by associating any usual identification and control methods (e.g., Recursive Minimum Square, Stochastic Approximation, Extended Kalman Filter, for Identification; Model Reference, Pole Placement, Quadratic Optimization, for Control).

TL;DR: In this paper, the problem of stabilization of systems by means of stable compensations is considered, and results are derived for systems using observer�controller structures, for system using a cascade structure, and for nonlinear systems.

TL;DR: Three different versions of a stochastic Stackelberg closedloop dynamic game are presented and solved and it is shown that these problems can be reduced to a single solvable generic problem.

TL;DR: In this article, the authors use Laplace's method of steepest descent to study bifurcation in the presence of small noise, and apply it to the study of the dynamics of noisy, constrained or implicitly defined dynamical systems.

TL;DR: In this article, the absolute stability of single-input, single-output (SISO) singularly perturbed systems with a time varying feedback element is examined via the Popov-Kalman-Yakubovich (PKY) lemma.

TL;DR: In this article, a minimum principle for stochastic control problems with output feedback was derived by applying Bismut's minimum principle to the Kushner-Stratonovitch equation describing the controlled evolution of the conditional density of the state.

TL;DR: A local version of this result is obtained here for nonlinear systems which are affine in control by use of appropriate feedback.

TL;DR: In this paper, a new algebro-analytic approach to the theory of linear systems and filters is presented, based on the Heaviside-Mikusinski operational calculus and algebraic and differential-algebraic function fields.

TL;DR: Given a (nonlinear) filtering problem there is associated to it a Lie algebra L (Σ) of differential operators which is the Lie algebra generated by the two operators occurring in the Zakai equation for the unnormalized conditional density of the problem.

TL;DR: In this paper, the (C,A )-invariant subspaces of a given observable pair (c,A) are parametrized via their uniquely determined Kronecker-Hermite bases.

TL;DR: In this paper, it is shown that many of these concepts are directly related to the index of a system, and that the index is directly related with the order of the system.

TL;DR: This paper presents some thoughts on the potential and the pittfalls of the interactive use of computers in control system design, and its consequences on the engineering profession.

TL;DR: The controllability of nonlinear discrete-time systems is related to Ritt's formal differential groups as mentioned in this paper, which is a well-known property of discrete time systems. But it is not applicable to nonlinear continuous-time nonlinear systems.

TL;DR: An optimal pointwise control problem for systems governed by a parabolic equation is studied and a transposed Galerkin type method is used for approximating this equation.

TL;DR: In this paper, the continuity of the closed-loop poles of a linear multivariable system with respect to a multidimensional polynomial family of direct output gains was discussed.

TL;DR: In this paper, the authors define a weak solution of the Hamilton-Jacobi-Bellman equation as the maximum of all subsolutions and present an iterative scheme for the computation of the weak solution.

TL;DR: For linear time-varying discrete-time systems, left, right, weak left, and weak right ivnertibility is defined in this paper, and it is shown that left and weak left invertibility are dual D right and strong right invertivity respectively.

TL;DR: In this article, the transfer function of a system with input, state and output delays is defined using a (local) MacMillan-Smith form for meromorphic matrices, and some of their properties are investigated.