Least-Squares Solution (LSS) of a linear matrix equation and Ordinary Least-Squares Estimator (OLSE) of unknown parameters in a general linear model are two standard algebraical methods in computational mathematics and regression analysis. Assume that a symmetric quadratic matrix-valued function φ(Z) = Q − ZPZ′ is given, where Z is taken as the LSS of the linear matrix equation AZ = B. In this ...

Abstract We consider an initial value problem for a Hamilton–Jacobi equation with quadratic and degenerate Hamiltonian. Our Hamiltonian comes from the dynamics of N -peakon in Camassa–Holm equation. It is given by form singular positive semi-definite matrix. Such does not fall into standard theory viscosity solutions. Also viability related results, sometimes used to deal Hamiltonians, do seem ...

The linear quadratic optimal regulator problem on a wave equation in a bounded subset of R n for n = 2; 3 with boundary damping and pointwise control input is formulated as a linear quadratic control problem with unbounded input/output operators using a variational approach. A dual control system is deened which allows us to investigate the regularity of the solution of the generalized wave equ...

The T-palindromic quadratic eigenvalue problem (λB + λC + A)x = 0, with A,B,C ∈ Cn×n, C = C and B = A, governs the vibration behavior of trains. One way to solve the problem is to apply a structure-preserving doubling algorithm (SDA) to the nonlinear matrix equation (NME) X + BX−1A = C and “square-root” the matrix quadratic involved. In this paper, we generalize the SDA for the solution of (odd...

it is proved that by using bounds of eigenvalues of an interval matrix, someconditions for checking positive de niteness and stability of interval matricescan be presented. these conditions have been proved previously with variousmethods and now we provide some new proofs for them with a unity method.furthermore we introduce a new necessary and sucient condition for checkingstability of interv...

The linear quadratic optimal regulator problem on a wave equation in a bounded subset of R for n = 2; 3 with boundary damping and pointwise control input is formulated as a linear quadratic control problem with unbounded input/output operators using a variational approach. A dual control system is de ned which allows us to investigate the regularity of the solution of the generalized wave equat...

The optimal control problem in a finite time horizon with an indefinite quadratic cost function for a linear system subject to multiplicative noise on both the state and control can be solved via a constrained matrix differential Riccati equation. In this paper, we provide general necessary and sufficient conditions for the solvability of this generalized differential Riccati equation. Furtherm...

in cite{p}, park introduced the quadratic $rho$-functional inequalitiesbegin{eqnarray}&& |f(x+y)+f(x-y)-2f(x)-2f(y)| && qquad le  left|rholeft(2 fleft(frac{x+y}{2}right) + 2 fleft(frac{x-y}{2}right)- f(x) -  f(y)right)right|,  nonumberend{eqnarray}where $rho$ is a fixed complex number with $|rho|andbegin{eqnarray}&& left|2 fleft(frac{x+y}{2}right) + 2 fleft(frac{x-y}{2}r...