Proper Pareto Optimality In Nonconvex Problems - Characterization With Tangent And Normal Cones

Study of proper Pareto optimality in multiobjective optimization means that we concentrate on solutions with bounded trade-oos. Henig and Buchanan have generalized in Mathematical Programming 78(3), 1997 the concept of trade-oos in convex multiobjective optimization problems. With the help of tangent cones they deene a cone of trade-oo directions. Here we generalize these tangent cones and their polar cones, normal cones, into nonconvex problems with the help of Clarke's nonconvex analysis. We also study the relationships between tangent and normal cones and proper Pareto optimality.