The mathematics of crystalline structures connects analysis, geometry, algebra, and number theory. The planar crystallographic groups were classified in the late 19th century. One hundred years later, ...

It has been shown previously that homogeneous time-invariant systems produce exponential outputs in response to similar exponential inputs, but that the concepts of "impulse response" and "frequency ...

K. Uhlenbeck, Generic Properties of Eigenfunctions, American Journal of Mathematics, Vol. 98, No. 4 (Winter, 1976), pp. 1059-1078 ...

We propose a Koopman operator-based surrogate model for propagating parameter uncertainties in power system nonlinear dynamic simulations. First, we augment a priori known state-space model by ...