It is easy to verify that the chromatic polynomial of a graph with order at most 4 has no non-integer real zeros, and there exists only one 5-vertex graph having a non-integer real chromatic root. This paper shows that, for 66 n6 8 and n¿ 9, the largest non-integer real zeros of chromatic polynomials of graphs with order n are n − 4 + =6 − 2= , where = ( 108 + 12 √ 93 )1=3 , and ( n− 1 +√(n− 3)...

Multi-objective optimization is the simultaneous consideration of two or more objective functions that are completely or partially inconflict with each other. The optimality of such optimizations is largely defined through the Pareto optimality. Multiple objective integer linear programs (MOILP) are special cases of multiple criteria decision making problems. Numerous algorithms have been desig...

let g be a transitive permutation group on a set ? and let m be a positive integer. if no element of g moves any subset of ? by more than m points, then |? | [2mp i (p-1)] wherep is the least odd primedividing |g |. when the bound is attained, we show that | ? | = 2 p q ….. q where ? is a non-negative integer with 2 < p, r 1 and q is a prime satisfying p < q < 2p, ? = 0 or 1, i i n. furthermore...

data envelopment analysis (dea) has been widely studied in the literature since its inception with charnes, cooper and rhodes work in 1978. the methodology behind the classical dea method is to determine how much improvements in the outputs (inputs) dimensions is necessary in order to render them efficient. one of the underlying assumptions of this methodology is that the units consume and prod...