I also have problems with a lot of the other recategorisation you have done to these articles, but I won't revert any more until I hear from you.  Taking <url> as an example: why have you removed it from <url> when it clearly is a linear filter; why remove it from <url> when it forms part of image parameter theory; why does an article which discusses electronic designs not belong in <url>; why remove it from <url> when, obviously, it is a term?