Two models of 2d photonic crystal of line defects and nonperiodic dielectric rods are established. The finite-difference-time-domain method is developed for the study of bandgap.

构建了介质柱间距变化的变周期结构以及介质柱半径线缺陷两种二维光子晶体模型，并将时域有限差分法用于其能带特性研究。

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As with a faulty assembly line, when defects go unspotted until the end of the process it is usually too late to fix them.

ECONOMIST: Education

These measurement systems provide real-time analysis that can identify errors and defects on an assembly line.

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There is nothing to be gained from tolerating defects on the production line or mistakes in the operating theatre.

ECONOMIST: Schumpeter