The concept of differential uniformity was recently extended to the $c$-differential uniformity. An interesting problem in this area is the construction of functions with low $c$-differential uniformity and a lot of research has been done in this direction in the recent past. Here, we present three classes of (almost) perfect $c$-nonlinear permutations over finite fields of even characteristic.

翻译：差异统一的概念最近扩大到了美元差异统一的概念,这个领域一个有趣的问题是,在构建功能时,美元差异统一性较低,最近在这方面进行了大量研究。 我们在这里提出了三种(几乎)完美(近似)的美元-非线性对等(c$-非线性)对甚至具有特征的有限领域的影响。