The properties of long period gratings in photonic crystal fibers (PCFLPG) are systematically analyzed by the improved full-vector effective index model and the coupled mode theory.

将修正的矢量等效折射率模型和耦合模理论相结合，系统地研究了光子晶体光纤长周期光栅(PCFLPG)的特性。

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Compared with the traditional subjective judgments of administrative staff and single evaluation index model, DEA model has offered a more effective method in appraising advertisement effect.

同传统的管理人员主观判断和单一评价指标相比，DEA模型提供了一种更为有效的广告效果评价方法。

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After defining a effective index for process similarity, an analogue model, which is suitable for doing similarity forecast for a time series, was established.

通过寻找过程相似的有效指标，建立了一个适合于时间序列分析的相似预报模式。

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