in this paper the class of n-ary hypergroups is introduced and several properties are found andexamples are presented. n-ary hypergroups are a generalization of hypergroups in the sense of marty. on theother hand, we can consider n-ary hypergroups as a good generalization of n-ary groups. we define thefundamental relation β* on an n-ary hypergroup h as the smallest equivalence relation such tha...

Any belief function can be decomposed into a confidence and a diffidence components. Each components is uniquely decomposable into simple support functions that represent the impact of the simplest form of evidence, the one that only partially supports a given subset of the frame of discernment. The nature of the inverse of Dempster's rule of combination is detailed. The confidence component tr...

We prove that various concrete analytic equivalence relations arising in model theory or analysis are complete, i.e. maximum in the Borel reducibility ordering. The proofs use some general results concerning the wider class of analytic quasi-orders.

The paper presents a selection of recently developed and/or used techniques for equivalencechecking on infinite-state systems, and an up-to-date overview of existing results (as of September 2004).

We provide a very simple model of a reeective facility based on the pure-calculus, and we show that its theory of contextual equivalence is trivial: two terms in the language are contextually equivalent ii they are-congruent.

In this draft we extend the theoretical development in [1, Appendix C] to enable the Decomposition Algorithm to compute equilibria with arbitrary accuracy.

A method for partitioning shapes is described based on a global convexity measure. Its advantages are that its global nature makes it robust to noise, and apart from the number of partitioning cuts no parameters are required. In order to ensure that the method operates correctly on bent or undulating shapes a process is developed that identifies the underlying bending and removes it, straighten...

We highlight a question about binary necklaces, i.e., equivalence classes of binary strings under rotation. Is there a way to choose representatives of the n-bit necklaces so that the subposet of the Boolean lattice induced by those representatives has a symmetric chain decomposition? Alternatively, is the quotient of the Boolean lattice Bn, under the action of the cyclic group Zn, a symmetric ...

People usually regard algorithms as more abstract than the programs that implement them. The natural way to formalize this idea is that algorithms are equivalence classes of programs with respect to a suitable equivalence relation. We argue that no such equivalence relation exists.