For centuries, humans have lived underground. Today, that ancient practice is under dire threat—even as cave life makes more ...

That’s exactly what happens at Indian Echo Caverns in Hummelstown, Pennsylvania – a subterranean wonderland that somehow remains one of the state’s best-kept secrets despite being, well, absolutely ...

As an illustration of how the SOS method can be used, the region of attraction (ROA) in a nonlinear polynomial system is analyzed in detail. The method of determining decision variables is given in ...