We propose a new way to derive tractable robust counterparts of a linear program by using the theory of Beck and Ben-Tal (2009) on the duality between the robust ("pessimistic") primal problem and its "optimistic" dual. First, we obtain a new convex reformulation of the dual problem of a robust linear program, and then show how to construct the primal robust solution from the dual optimal solution. Our result allows many new uncertainty regions to be considered. We give examples of tractable uncertainty regions that were previously intractable. The results are illustrated by solving a multi-item newsvendor problem. We also apply the new method to the globalized robust counterpart scheme and show its tractability.

Factory Gate Pricing (FGP) is a relatively new phenomenon in retail distribution. Under FGP, products are no longer delivered at the retailer distribution center, but collected by the retailer at the factory gates of the suppliers. Owing to both the asymmetry in the distribution networks (the supplier sites greatly outnumber the retailer distribution centers) and the better inventory and transport coordination mechanisms, this is likely to result in high savings. A mathematical model was used to analyze the benefits of FGP for a case study in the Dutch retail sector. Extensive numerical results are presented to show the effect of the orchestration shift from supplier to retailer, the improved coordination mechanisms, and sector-wide cooperation.

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We consider models of polling systems where switching times between channels are composed of two parts: walking times required to move from one channel (station) to another, and switch-in times that are incurred -only when the server enters a station to render service.We analyze three Gated-type systems: (i) Cyclic polling with Gated regime, (ii) Cyclic polling with Globally-Gated regime, and (iii) Elevator-type polling with Globally-Gated regime. In all systems, the server visits station i if and only if the number of customers