APPROXIMATE CONTROLLABILITY OF THE STOKES EQUATIONS WITH BOUNDARY CONDITION ON THE PRESSURE

In this paper, some properties of three-dimensional Stokes equations with boundary condition of pressure on parts of boundary are studied. By use of these properties, approximate controllability by tangent boundary controls acting on a subboundary is studied. In addition, the controllability problem is considered when its controls act on a subdomain.     

A global Carleman inequality and exact controllability of parabolic equations with mixed boundary conditions

This paper establishes a global Carleman inequality of parabolic equations with mixed boundary conditions and an estimate of the solution. Further, we prove exact controllability of the equation by controls acting on an arbitrarily given subdomain or subboundary.     

Kaplansky Density and Kadison Transitivity Theorems for Irreducible Representations of Real C＊-Algebras

We prove analogs of the Kaplansky Density Theorem and the Kadison Transitivity Theorem for irreducible representations of a real C＊-algebra on a real Hilbert space. Specifically, if a C＊-algebra is acting irreducibly on a real Hilbert space, then the Hilbert space has either a real, complex, or quaternionic structure with respect to which the density and transitivity theorems hold.     

COMPOSITION OPERATORS ON BERGMAN SPACES＊＊＊

The authors obtain function theoretic characterizations of the compactness on the Standard weighted Bergman spaces of the two operators formed by multiplying a composition operator with the adjoint of another composition operator.     

Exact Boundary Controllability for a Coupled System of Wave Equations with Neumann Boundary Controls

This paper first shows the exact boundary controllability for a coupled system of wave equations with Neumann boundary controls.In order to establish the corresponding observability inequality,the authors introduce a compact perturbation method which does not depend on the Riesz basis property,but depends only on the continuity of projection with respect to a weaker norm,which is obviously true in many cases of application.Next,in the case of fewer Neumann boundary controls,the non-exact boundary controllability for the initial data with the same level of energy is shown.     

Long-time Dynamics for Thermoelastic Bresse System of Type Ⅲ

This paper considers the thermoelastic beam system of type Ⅲ with friction dissipations acting on the whole system. By using the methods developed by Chueshov and Lasiecka, we get the quasi-stability property of the system and obtain the existence of a global attractor with finite fractal dimension. Result on exponential attractors of the system is also proved.     

ON THE BEST APPROXIMATION MATRIX PROBLEM AND MATRIX FOURIER SERIES

In this paper the concept of positive definite bilinear matrix moment functional. acting on the space of all the matrix valued continuous functions defined on a bounded interval [a,b], is introduced. The best approximation matrix problem with respect to such a functional is solved in terms of matrix Fourier series. Basic properties of matrix Fourier series such as the Kiemann -Lebesgue matrix property and the bessel-parseval matrix inequality are proved. The concept of total set vjith respect to a positive definite matrix functional is introduced , and the totallity of an orthonormal sequence of matrix polynomials with respect to the functional, is established.     

SPECTRAL MAPPING THEOREM FOR ASCENT,ESSENTIAL ASCENT,DESCENT AND ESSENTIAL DESCENT SPECTRUM OF LINEAR RELATIONS

In [7], Cross showed that the spectrum of a linear relation T on a normed space satisfies the spectral mapping theorem. In this paper, we extend the notion of essential ascent and descent for an operator acting on a vector space to linear relations acting on Banach spaces. We focus to define and study the descent, essential descent, ascent and essential ascent spectrum of a linear relation everywhere defined on a Banach space X. In particular, we show that the corresponding spectrum satisfy the polynomial version of the spectral mapping theorem.     

The Semantical Completeness of the Extensions Ln^＊ to the System L^＊ ＊

The terminology of “fuzzy logic” has been formed and employed with different meanings by a large number of researchers soon after Zadeh published his initiate paper (see [1]), but perhaps the most serious work on fuzzy logic is the Pavelka‘s series papers (see [2]) which provided a systematical theory of fuzzy logic mathematically and profoundly, and hence has been accepted by scholars as a standard theory in developing their researches on fuzzy logic.     

Exact Controllability and Asymptotic Analysis for Shallow Shells

The authors consider the exact controllability of the vibrations of a thin shallow shell, of thickness 2εwith controls imposed on the lateral surface and at the top and bottom of the shell. Apart from proving the existence of exact controls, it is shown that the solutions of the three dimensional exact controllability problems converge, as the thickness of the shell goes to zero, to the solution of an exact controllability problem in two dimensions.     

An algorithm for reconstructing controls in a uniform metric

The problem of the dynamic reconstruction of unknown controls acting on a non-linear vector differential equation is discussed. Two regularizing algorithms are presented that enable these controls to be reconstructed in a uniform metric synchronously with the development of the processes considered. The algorithms are stable to information noise and errors in the calculations.     

Exact Controllability with Internal Controls

For first-order quasilinear hyperbolic systems with zero eigenvalues, the author establishes the local exact controllability in a shorter time-period by means of internal controls acting on suitable domains. In particular, under certain special but reasonable hypotheses, the local exact controllability can be realized only by internal controls, and the control time can be arbitrarily small.     

Exact Controllability with Internal Controls for First-Order Quasilinear Hyperbolic Systems with Zero Eigenvalues

For first-order quasilinear hyperbolic systems with zero eigenvalues, the author establishes the local exact controllability in a shorter time-period by means of internal controls acting on suitable domains. In particular, under certain special but reasonable hypotheses, the local exact controllability can be realized only by internal controls, and the control time can be arbitrarily small.     

Exact controllability for 1‐D quasilinear wave equations with internal controls

For 1‐D quasilinear wave equations with different types of boundary conditions, based on the theory of the local exact boundary controllability, using an extension method, the author establishes the exact controllability in a shorter time by means of internal controls acting on suitable domains. In particular, the exact controllability can be realized only by internal controls, and the control time can be arbitrarily small. Copyright © 2016 John Wiley & Sons, Ltd.     

Optimal Control for an SEIR Epidemic Model with Nonlinear Incidence Rate

The objective of this paper is to explore possible impacts of nonlinearity of functional responses and a number of compartments of an infection disease model on principal qualitative properties of the optimal controls. To address this issue, we consider optimal controls for an Susceptible‐Exposed‐Infectious‐Removed (SEIR) model of an endemically persisting infectious disease. We assume that the incidence rate is given by an unspecified nonlinear function constrained by a few biologically motivated conditions. For this model, we consider five controls (which comprise all controls that are possible for this model) with a possibility of acting simultaneously, and establish principal qualitative properties of the controls. A comparison with a similar SIR model is provided.     

LOCAL EXACT BOUNDARY CONTROLLABILITY FOR A CLASS OF QUASILINEAR HYPERBOLIC SYSTEMS

InroductionLet us consider the following irst order quaslllnear hyperbolic     

Asymptotic analysis of Neumann periodic optimal boundary control problem

An optimal boundary control problem in a domain with oscillating boundary has been investigated in this paper. The controls are acting periodically on the oscillating boundary. The controls are applied with suitable scaling parameters. One of the major contribution is the representation of the optimal control using the unfolding operator. We then study the limiting analysis (homogenization) and obtain two limit problems according to the scaling parameters. Another notable observation is that the limit optimal control problem has three controls, namely, a distributed control, a boundary control, and an interface control. Copyright © 2016 John Wiley & Sons, Ltd.     

Exact controllability of nodal profile for 1‐D first order quasilinear hyperbolic systems with internal controls

For 1‐D first order quasilinear hyperbolic systems without zero eigenvalues, based on the theory of exact boundary controllability of nodal profile, using an extension method, the exact controllability of nodal profile can be realized in a shorter time by means of additional internal controls acting on suitably small space‐time domains. On the other hand, using a perturbation method, the exact controllability of nodal profile for 1‐D first order quasilinear hyperbolic systems with zero eigenvalues can be realized by additional internal controls to the part of equations corresponding to zero eigenvalues. Furthermore, by adding suitable internal controls to all the equations on suitable domains, the exact controllability of nodal profile for systems with zero eigenvalues can be realized in a shorter time.     

Adaptive Robust Tracking for Flexible Spacecraft in Presence of Disturbances

The paper deals with trajectory tracking for a flexible spacecraft, subject to a gravity-gradient disturbance, under parameter uncertainties. The controls are gas jets and reaction wheels, and the measured variables describe the attitude and angular velocity of the rigid part. The flexible dynamics is treated as an additional disturbance acting on a rigid structure. First, an adaptive control is designed with only the gravity-gradient disturbance acting on the spacecraft; second, it is proved to be effective also in the presence of disturbance due to the flexibility, provided that appropriate robustness conditions on the controller gains are satisfied. These conditions use partial knowledge of the parameters describing the elastic dynamics. Simulations show the good performance of such control scheme and demonstrate its applicability even in the presence of input saturation.