继发于支气管和细支气管阻塞的空气潴留可产生局部低衰减带，后者应用呼气相ct可增强其表现。

Air trapping secondary to bronchial or bronchiolar obstruction may produce focal zones of decreased attenuation, an appearance that can be enhanced by using expiratory ct.

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因此，它在带外衰减与带内幅度特性和带内群时延特性之间有了一个较好的折中。

Therefore, there is a perfect compromise between attenuation in stopband and group delay or loss variation in passband.

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此软件能根据一定的技术指标要求(如带宽、带外衰减等)，优化出双工器最佳参数。

According to the designing demands, such as bandwidth, stop-band attenuation, the optimization software can optimize the diplexers.

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