Constrained regular LQ-control problems

G Stefani, P Zezza - SIAM journal on control and optimization, 1997 - SIAM
In this paper we give a complete description of how the Jacobi theory of conjugate points
can be extended to a regular linear-quadratic control problem where the state end-points …

Discrete optimal control: second order optimality conditions

R Hilscher, V Zeidan - The Journal of Difference Equations and …, 2002 - Taylor & Francis
In this paper, we present a survey and refinement of our recent results in the discrete optimal
control theory. For a general nonlinear discrete optimal control problem (P), second order …

An invariant second variation in optimal control

A Agrachev, G Stefani, P Zezza § - International Journal of Control, 1998 - Taylor & Francis
For an optimal control problem we define a second variation which is invariant under
change of coordinates, and realize it as a linear-quadratic problem. When the strong …

Symplectic difference systems: variable stepsize discretization and discrete quadratic functionals

R Hilscher, V Zeidan - Linear algebra and its applications, 2003 - Elsevier
Discrete quadratic functionals with variable endpoints for variable stepsize symplectic
difference systems are considered. A comprehensive study is presented for characterizing …

Nonnegativity and positivity of quadratic functionals in discrete calculus of variations: survey

R Hilscher, V Zeidan - Journal of Difference Equations and …, 2005 - Taylor & Francis
In this paper we provide a survey of characterizations of the nonnegativity and positivity of
discrete quadratic functionals which arise as the second variation for nonlinear discrete …

Time scale embedding theorem and coercivity of quadratic functionals

R Hilscher, V Zeidan - Analysis, 2008 - degruyter.com
In this paper we study the relation between the coercivity and positivity of a time scale
quadratic functional J, which could be a second variation for a nonlinear time scale calculus …

Geometrical and topological methods in optimal control theory

SA Vakhrameev - Journal of Mathematical Sciences, 1995 - Springer
The present article will appear 30 years after Hermann's report [840] was published; in that
report, the foundations of a new direction in optimal control theory, later called geometrical …

Quadratic functionals with general boundary conditions

Z Došlá, O Došlý - Applied Mathematics and Optimization, 1997 - Springer
The purpose of this paper is to give the Reid``Roundabout Theorem''for quadratic
functionals with general boundary conditions. In particular, we describe the so-called …

Coupled intervals in the discrete calculus of variations: necessity and sufficiency

R Hilscher, V Zeidan - Journal of mathematical analysis and applications, 2002 - Elsevier
In this work we study nonnegativity and positivity of a discrete quadratic functional with
separately varying endpoints. We introduce a notion of an interval coupled with 0, and …

[PDF][PDF] Diagonalization approach to discrete quadratic functionals

M Bohner, O Došlý, R Hilscher, W Kratz - Arch. Inequal. Appl, 2003 - mst.edu
Archives of Inequalities and Applications 1 (2003) 1-7 DIAGONALIZATION APPROACH TO
DISCRETE QUADRATIC FUNCTIONALS 1. INTRODUCTIO Page 1 Archives of Inequalities and …