比利时vs摩洛哥足彩
,
university of california san diego
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computational and applied mathematics seminar
emre mengi
ucsd
a backward approach for model reduction
abstract:
the differential equation $\dot{x}(t) = ax(t) + bu(t)$ coupled with the
algebraic equation $y(t) = cx(t) + du(t)$ where $a\in\mathbb{c}^{n\times n}$,
$b\in\mathbb{c}^{n\times m}$, $c\in\mathbb{c}^{p\times n}$ is
called a state space system and commonly employed to represent
a linear operator from an input space to an output space in control
theory. one major challenge with such a representation is that
typically $n$, the dimension of the intermediate state function $x(t)$,
is much larger than $m$ and $p$, the dimensions of the input
function $u(t)$ and the output function $y(t)$. to reduce the order of
such a system (dimension of the state space) the traditional
approaches are based on minimizing the $h_{\infty}$ norm of the
difference between the transfer functions of the original system and
the reduced-order system. we pose a backward error minimization
problem for model reduction in terms of the norms of the
perturbations to the coefficients $a$, $b$ and $c$ such that the
perturbed systems are equivalent to systems of order $r
june 5, 2007
11:00 am
ap&m 5402
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