Three types of commercially-available electric (415 V, three-phase) catering hobs, namely the [`]induction', [`]halogen' and conventional resistance hot plates have been tested. For each, assessments have been made of: 1. (i) the rate of energy consumption; 2. (ii) controllability and...

We consider k-regular graphs with loops, and study the Lovasz O-numbers and Schrijver O-numbers of the graphs that result when the loop edges are removed. We show that the O-number dominates a recent eigenvalue upper bound on the stability number due to Godsil and Newman [C.D. Godsil and M.W....