The paper introduces the worst-case portfolio optimization models within robust framework for maximizing return through either mean or median metrics. risk in is quantified by Gini difference. We put forward under mixed and interval+polyhedral uncertainty sets. proposed turn out to be linear integer programs set, semidefinite program set. performance comparison of on listed stocks Euro Stoxx 50...

Cyclically Indecomposable Triple Systems that are Decomposable Martin Grüttmüller Institut für Mathematik, Universität Rostock In this talk, we construct, by using Skolem-type and Rosa-type sequences, cyclically indecomposable two-fold triple systems TS2(v) for all admissible orders. We also investigate exhaustively the cyclically indecomposable triple systems TSλ(v) for λ = 2, v ≤ 33 and λ = 3...

In 2000, Rees and Shalaby constructed simple indecomposable two-fold cyclic triplesystems for all v ≡ 0, 1, 3, 4, 7, and 9 (mod 12) where v = 4 or v ≥ 12, using Skolem-type sequences.We construct, using Skolem-type sequences, three-fold triple systems having theproperties of being cyclic, simple, and indecomposable for all admissible orders v, withsome possible exception...