This paper is concerned with the existence results for generalized transition waves of space periodic and time heterogeneous lattice Fisher-KPP equations. By constructing appropriate subsolutions and supersolutions, we show that there is a critical wave speed such that a transition wave solution exists as soon as the least mean of wave speed is above this critical speed. Moreover, the critical speed we construct is proved to be minimal in some particular cases, such as space-time periodic or space independent.

中文翻译：

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具有时间和空间依赖性的格Fisher-KPP方程的过渡波

本文研究空间周期和时间异质格Fisher-KPP方程的广义跃迁波的存在性结果。通过构造适当的子解和超解，我们表明存在临界波速，使得一旦波速的最小均值高于该临界速度，就会存在过渡波解。此外，我们构建的临界速度在某些特定情况下被证明是最小的，例如时空周期性或空间无关。