Extracting governing equations from data is a central challenge in many diverse areas of science and engineering. Data are abundant whereas models often remain elusive, as in climate science, ...

This example illustrates the use of the MODEL procedure for nonlinear ordinary least-squares (OLS) regression. The model is a logistic growth curve for the population of the United States. The data is ...

We introduce mountain-pass type arguments in the context of orbital instability for Klein-Gordon equations. Our aim is to illustrate on two examples how these arguments can be useful to simplify ...