A class of linear systems described by rational transfer functions with interval parameters and fixed time-delay values is considered in this study. The ranges of variation of the interval parameters depends on the total range of perturbations. A sufficient frequency criterion for robust modality is formulated. This criterion is determined by the inclusion of all the roots of a system characteristic quasi-polynomial to the region located to the left of the given position of the vertical boundary. The advantage of the developed criterion in comparison with similar ones is the possibility of refusing to analyze the set of characteristic quasi-polynomials of the system, as well as refusing to analyze the nominal system. This provides by constructioning and studying only two hodographs. In special cases, the developed criterion coincides with the known frequency criteria for system analysis.

中文翻译：

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一类具有时滞的线性系统鲁棒模态的频率判据

本研究考虑了一类由具有区间参数和固定时延值的有理传递函数描述的线性系统。区间参数的变化范围取决于扰动的总范围。制定了鲁棒模态的足够频率标准。该标准是通过将系统特征拟多项式的所有根包含到位于垂直边界给定位置左侧的区域来确定的。与同类准则相比，所开发准则的优点是可以拒绝分析系统的特征拟多项式集，也可以拒绝分析标称系统。这仅通过构建和研究两个全线图来提供。在特殊情况下，