Rank inequalities and separation algorithms for packing designs and sparse triple systems

Packing Steiner Trees: Separation Algorithms

In this paper we investigate separation problems for classes of inequalities valid for the polytope associated with the Steiner tree packing problem , a problem that arises, e. g., in VLSI routing. The separation problem for Steiner partition inequalities is NP-hard in general. We show that it can be solved in polynomial time for those instances that come up in switchbox routing. Our algorithm ...

Algorithms to Approximate Column-Sparse Packing Problems

Column-sparse packing problems arise in several contexts in both deterministic and stochastic discrete optimization. We present two unifying ideas, (non-uniform) attenuation and multiple-chance algorithms, to obtain improved approximation algorithms for some well-known families of such problems. As three main examples, we attain the integrality gap, up to lower-order terms, for known LP relaxat...

Algorithms for Packing and Scheduling

This is the Second Year Progress Report for the “Algorithms for Packing and Scheduling” Ph.D. project. In this report, we give the aims of the project, a summary of the current results obtained, we address the questions raised in the Postgraduate Workshop, and we conclude with possible future work and a timetabled research plan. The project is concerned with the study, design, and analysis, of ...

Iterative algorithms for families of variational inequalities fixed points and equilibrium problems

Further 6-sparse Steiner Triple Systems

We give a construction that produces 6-sparse Steiner triple systems of order v for all sufficiently large v of the form 3p, p prime and p ≡ 3 (mod 4). We also give a complete list of all 429 6-sparse systems with v < 10000 produced by this construction.