Thanks for the link. This is a typical example of how a simple idea can be presented in an insanely complex way to become a scientific article.
It seems to me that this idea is familiar to me, perhaps from diode functional converters with a segment approximation... or from my LED voltage indicato
This is an example of artificially created differential resistance. Actually it is "over dynamic resistance" (I have explained it in en.wikibooks.org/wiki/Circuit_Idea/…). Cheers!
Bob DuHamel is an amazing phenomenon. It gives me great pleasure to watch it.