A List of Notations Table 1: Notations and their meanings Notation Meaning C = { C, C2

Based on Minkowski's inequality for sums [2] with order 2: Using Eq. 1 and 3, Eq. 4 can be proved. Using Eq. 3, 10, and 2, we have the following distance(o Eq. 6 can be proved. Similar to proof in C, Theorem 4 can be proved. Theorem 1, 2 and Theorem 3, 4 can be generalized to Minkowski distance with order q, q > 1. Using Eq. 11 and 3, Eq. 4 can be proved.