March 2015 – Page 6 – Optimization Online

On the closure of the completely positive semidefinite cone and linear approximations to quantum colorings

Published: 2015/03/02

Linear, Cone and Semidefinite Programming, Polyhedra chromatic number, copositive programming, nonlocal games, quantum entanglement, quantum graph parameters, trace nonnegative polynomials, von neumann algebra

We investigate structural properties of the completely positive semidefinite cone, consisting of all the nxn symmetric matrices that admit a Gram representation by positive semidefinite matrices of any size. This cone has been introduced to model quantum graph parameters as conic optimization problems. Recently it has also been used to characterize the set Q of … Read more

Asymptotic optimality of Tailored Base-Surge policies in dual-sourcing inventory systems

Published: 2015/03/02, Updated: 2016/04/20

David A. Goldberg

Linwei Xin

Dynamic Programming, Stochastic Programming, Supply Chain Management asymptotic optimality, dual-sourcing, inventory, lead time, steady state, tailored base-surge policy (tbs)

Dual-sourcing inventory systems, in which one supplier is faster (i.e. express) and more costly, while the other is slower (i.e. regular) and cheaper, arise naturally in many real-world supply chains. These systems are notoriously difficult to optimize due to the complex structure of the optimal solution and the curse of dimensionality, having resisted solution for … Read more