這篇文章提出了一些估計 $mu$-norm 上界的數值方法。 由一些文獻中可知，計算 $mu$-norm 及其下界為 NP-hard 的問題。 因此在本文中我們專注於 $mu$-norm 上界的估計。

In this paper, some numerical algorithms for the
computation of an upper bound of the $mu$-norm are proposed. Some
literature have shown that the computations for $mu$-norm and its
lower bound are NP-hard problems. Hence, in this paper, we
concentrate on the computation of an upper bound of $mu$-norm.

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