For time-domain electromagnetics, the choice of time scheme is very pivotal. Usually, an explicit time scheme has the stability constraint on small grid size. Though the implicit time scheme is unconditionally stable, it has a necessary expense of computing the global system at each time iteration. To alleviate the expensive computational cost, a new explicit-implicit hybridizable discontinuous Galerkin time-domain method that combines the explicit DGTD (exDGTD) method and our former imHDGTD method will be proposed for the first time. Here let’s call it exDGTD-imHDGTD (ex-imHDGTD). This letter gives its implementation, including a new transmission condition. Unlike the traditional explicit–implicit methods, imHDGTD is used to replace traditional implicit algorithms for the refined region, which leads to a remarkable reduction of degrees of freedom (DOFs) and a better matrix solving ability. Numerical results show that the proposed ex–imHDGTD is very effective both on accuracy and performance.

中文翻译：

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一种新的显式-隐式可杂化不连续 Galerkin 时域电磁学方法

对于时域电磁学，时间方案的选择非常关键。通常，显式时间方案对小网格尺寸具有稳定性约束。尽管隐式时间方案是无条件稳定的，但它在每次迭代时都需要计算全局系统。为了减轻昂贵的计算成本，将首次提出一种结合显式DGTD（exDGTD）方法和我们以前的imHDGTD方法的新的显式-隐式可混合不连续Galerkin时域方法。这里我们称它为 exDGTD-imHDGTD (ex-imHDGTD)。这封信给出了它的实现，包括一个新的传输条件。与传统的显式-隐式方法不同，imHDGTD 用于替代传统的精化区域隐式算法，这导致自由度（DOF）的显着降低和更好的矩阵求解能力。数值结果表明，所提出的 ex-imHDGTD 在准确性和性能方面都非常有效。