After that we studied several Post-processing models based on PDE of Anisotropic Diffusion, including Directional Diffusion and Self-Snake model.

进而深入研究了经典的基于偏微分方程的后处理方法，包括方向扩散，自蛇模型等非线性扩散方程。

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Similarly, when an octopus changes skin color in self-defense, such as by mimicking a poisonous sea snake, the decision may come not from central command but from the skin itself.

WSJ: The Brains of the Animal Kingdom