We discuss the numerical solution of linear quadratic optimal control problems for descriptor systems. The classical solution approach for these problems requires the computation of deeating subspaces of structured pencils. We extend the recently developed methods 6] for Hamiltonian matrices to the general case of embedded pencils as they arise in descriptor systems.

Numerical integration of stiffness matrices in finite element analysis can represent a significant portion of the overall computational effort. To improve computational efficiency, it has become a practice of some analysts to 'underintegrate' the various element stiffnesses. i,e. to employ a numerical quadrature rule of an order less than that required to yield exact values for polynomial integ...

We discuss a number of novel issues in the interdisciplinary area of numerical linear algebra and control theory. Although we do not claim to be exhaustive we give a number of problems which we believe will play an important role in the near future. These are : sparse matrices, structured matrices, novel matrix decompositions and numerical shortcuts. Each of those is presented in relation to a ...

In the present paper an active control mechanism for the control of laminar separation bubbles on airfoils is investigated by means of direct numerical simulation and linear stability theory. Boundary layer instabilities excited by periodic oscillations are utilized to control the size and length of the separation bubble and to make it finally disappear when desired. Unlike traditional vortex g...

Abstract: This paper reports about progress in the development of numerical tools for adaptive aerodynamic configuration design. We try to illustrate the use of new software components allowing for the parameterized modelling of boundary conditions and the simulation of compressible steady and unsteady viscous flows including a computational flow control model. A coupling of these tools and the...

We numerically investigate the sense in which an adaptive control law achieves internal model control of Hammerstein plants with Prandtl–Ishlinskii hysteresis. We apply retrospective cost adaptive control to a command-following problem for uncertain Hammerstein systems with hysteretic input nonlinearities. The only required modeling information of the linear plant is a single Markov parameter. ...

Optimal control theory is applied to a system of ordinary differential equations modeling a two-strain tuberculosis model. Seeking to reduce the latent and infectious groups with the resistant-strain tuberculosis, we use controls representing two types of treatments. The optimal controls are characterized in terms of the optimality system, which is solved numerically for several scenarios.

Based on the mechanism and characteristics of measles transmission, we propose a susceptible-exposed-infectious-recovered (SEIR) measles epidemic model with vaccination and investigate the effect of vaccination in controlling the spread of measles. We obtain two critical threshold values, lc1 and lc2, of the vaccine coverage ratio. Measles will be extinct when the vaccination ratio l > lc1, end...

In this study an observer-based novel design of robust control system with an estimate scheme of sensor states to accommodate extended bounded-sensor faults is proposed. The sensor faults are, in general, modeled as polytopic bounds in robust control framework and are usually given as a priori assumption. But, in practice, the sensors that are subject to faults are especially vulnerable to vari...