Principal structure of submodular systems and hitchcock-type independent flows


This paper discusses the principal structure of submodular systems due to S. Fujishige. It is shown that the principal structure is the coarsest decomposition that is finer than any decomposition induced by the principal partition with respect to a minimal nonnegative superbase. The concept of “Hitchcock-type independent flow” is introduced so that previously known results on the principal structures for bipartite matchings, layered mixed matrices and independent matchings can be understood as applications of the present result.

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Iwata, S. Principal structure of submodular systems and hitchcock-type independent flows. Combinatorica 15, 515–532 (1995).

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Mathematics Subject Classification (1991)

  • 05 B 35
  • 90 C 27