TY - JOUR A1 - Möller, Bernhard T1 - Towards antichain algebra T2 - Lecture Notes in Computer Science N2 - We use an algebra of preference strict-orders to give a formal derivation of the standard Block-Nested Loop (BNL) algorithm for computing the best or maximal objects w.r.t. such an order. This derivation is presented in terms of antichains, i.e., sets of mutually incomparable objects. We define an approximation relation between antichains that reflects the steps taken by the BNL algorithm. This induces a semilattice and the operator computing the maximal objects of a subset can be viewed as a closure operator in an associated pre-ordered set and hence yields a characterisation of antichains in terms of a Galois connection. Y1 - 2015 UR - https://opus.bibliothek.uni-augsburg.de/opus4/frontdoor/index/index/docId/58734 UR - https://nbn-resolving.org/urn:nbn:de:bvb:384-opus4-587347 SN - 9783319247038 SN - 9783319247045 SN - 0302-9743 SN - 1611-3349 VL - 9348 SP - 344 EP - 361 PB - Springer International CY - Cham ER -