An "intelligence" is " a system to handle all of the calculations from crude inputs through to overt actions in an adaptive way so as to maximize some measure of performance over time" (P. J. Werbos, IEEE Trans. Systems, Man, and Cybernetics, 1987, pg 7) This intelligence might be the brain of a robot which operates in the real world. An example of such a system would be my Asa H (see, for example, my 10 Feb. 2011 blog).
"Knowledge" is then the set of patterns learned by such a system and used by it to "live." (see, for a simple example, my 22 Nov. 2010 blog or the examples in chapter 1 of my book TWELVE PAPERS, amazon ASIN: B005SVVEYC) In general this knowledge is approximate and fallible.