Yunnan is a seismic active region.

云南是一个地震活动区。

A first active region in the semiconductor substrate;

位于所述半导体衬底中的第一有源区；

The active region of lasers have been designed and optimized.

结合材料生长条件,对激光器的有源区进行了优化设计,为激光器的研制打下了基础和提供了理论依据.

And a second active region in the semiconductor substrate and of an opposite conductivity type than the first active region.

位于所述半导体衬底中并具有和所述第一有源区相反导电类型的第二有源区；

The main characteristics of the perturbations can be explained by the variations of the ionizing sources which were located in the solar active region.

利用当时太阳活动区离化源的变化可以解释扰动的主要特征。

The sand area in Yulin lies in the southeast of the Maowusu desert, which is the most active region, where the Maowusu desert migrates to the southeast.

榆林沙区地处毛乌素沙地的东南部，属毛乌素沙地向东南移动的最活跃地段。

For an SOA with an active region with a wide material gain spectrum, an optimal antireflection coating helps to realize an SOA-based incoherent optical source with a high bandwidth and good flatness.

而在采用具有宽带材料增益谱的有源区基础上，结合抗反膜的优化设计，则可以获得既宽又平坦的非相干光源。