Sémantique catégorique des constructeurs de types d'ordre supérieur
In [12] Trillas proved that (P(X),∩,U,-n) is a quasi-Boolean algebra if and only if its negation has an additive generator. In this paper such result is generalized to PJ(X) and the symmetry of J is analized.From the results of Esteva ([11]) weak negations on [0,1] are studied; it is proved that such functions are monotonic, non-increasing, left-continuous and symmetrical with respect to y=x. Their classification relative to C([0,1]) is also given and a canonical element of each class is found....
This paper presents some manner of characterization of Boolean rings. These algebraic systems one can also characterize by means of some distributivities satisfied in GBbi-QRs.
This paper represents a start in the study of epimorphisms in some categories of Hilbert algebras. Even if we give a complete characterization for such epimorphisms only for implication algebras, the following results will make possible the construction of some examples of epimorphisms which are not surjective functions. Also, we will show that the study of epimorphisms of Hilbert algebras is equivalent with the study of epimorphisms of Hertz algebras.
In this paper, we prove that Eulerian lattices satisfying some weaker conditions for lattices or some weaker conditions for 0-distributive lattices become Boolean.