Popular branchings and their dual certificates

Mathematical Programming - Let G be a digraph where every node has preferences over its incoming edges. The preferences of a node extend naturally to preferences over branchings, i.e., directed...     

Protection of flows under targeted attacks

We present a new robust optimization model for the problem of maximizing the amount of flow surviving the attack of an interdictor. Given some path flow, our model allows the interdictor to specify the amount of flow removed from each path individually. In contrast to previous models, for which no efficient algorithms are known, the most important basic variants of our model can be solved in poly-time. We also consider extensions where there is a budget to set the interdiction costs.     

Polarographisches Verhalten von Dicyanmethanidooxoanionen

The polarographic behaviour of the anions nitrosodicyanmethanide and nitrodicyanmethanide is described. Contrary to the homologous oxoanions nitrite and nitrate the dicyanmethanidooxoanions are reduced, hydroxylamine being formed as an intermediate product, The results are discussed, assuming an influence of the asymmetric structure of the anions.