This paper will discuss and characterise the cardinality of boolean (crisp) and fuzzy relations. The main result is a Dedekind inequality for the cardinality, which enables us to manipulate the cardinality of the composites of relations. As applications a few relational proofs for the basic theorems on graph matchings, and fundamentals about network flows will be given.


Distinct Element Transitive Closure Fuzzy Relation Graph Matchings Univalent Relation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Yasuo Kawahara
    • 1
  1. 1.Department of Informatics, Kyushu University 33FukuokaJapan

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