Direct product decomposition of zero-product-associative rings without nilpotent elements
Directoids with an antitone involution
We investigate -directoids which are bounded and equipped by a unary operation which is an antitone involution. Hence, a new operation can be introduced via De Morgan laws. Basic properties of these algebras are established. On every such an algebra a ring-like structure can be derived whose axioms are similar to that of a generalized boolean quasiring. We introduce a concept of symmetrical difference and prove its basic properties. Finally, we study conditions of direct decomposability of directoids...
Discriminator order algebras
We prove that an order algebra assigned to a bounded poset with involution is a discriminator algebra.
Distributive ordered sets and relative pseudocomplements
Brouwerian ordered sets generalize Brouwerian lattices. The aim of this paper is to characterize (α)-complete Brouwerian ordered sets in a manner similar to that used previously for pseudocomplemented, Stone, Boolean and distributive ordered sets. The sublattice (G(P)) in the Dedekind-Mac~Neille completion (DM(P)) of an ordered set (P) generated by (P) is said to be the characteristic lattice of (P). We can define a stronger notion of Brouwerianicity by demanding that both (P) and (G(P)) be Brouwerian....
Distributive partially ordered sets
Edge theorem for finite partially ordered sets
Eine Bemerkung zum Kardinalprodukt
Einige Charakterisationen von Ketten
Embedding co-continuous posets in function spaces of domains.
Équilibre, équivalence, ordre et préordre à distance minimum d'un graphe complet
Les problèmes que nous traitons ici sont en partie familiers aux lecteurs de la revue. L'apport original consiste selon nous dans le fait d'avoir rapproché des problèmes classiques (équilibre d'un graphe, ordre à distance minimum) pour en souligner les analogies profondes et, du coup, plonger de manière féconde ces problèmes dans un ensemble plus large, en particulier en posant le problème de l'équivalence et du préordre à distance minimum d'un graphe complet. Notre exposé se présente donc comme...
Existence of prime ideals and ultrafilters in partially ordered sets
Extended blocker, deletion, and contraction maps on antichains.
Extension of topological homology theories to partially orderd sets.
Faserungen von Fahnenmengen
Field-independent representations of partially ordered sets.
Filters in partially ordered sets
Finite orders and their minimal strict completion lattices
Whereas the Dedekind-MacNeille completion D(P) of a poset P is the minimal lattice L such that every element of L is a join of elements of P, the minimal strict completion D(P)∗ is the minimal lattice L such that the poset of join-irreducible elements of L is isomorphic to P. (These two completions are the same if every element of P is join-irreducible). In this paper we study lattices which are minimal strict completions of finite orders. Such lattices are in one-to-one correspondence with finite...
Fixed edge theorems for complete lattices
Fixed point characterization of completeness on lattices for relatively isotone mappings
Fixed point results on a metric space endowed with a finite number of graphs and applications
In this paper, we consider self-mappings defined on a metric space endowed with a finite number of graphs. Under certain conditions imposed on the graphs, we establish a new fixed point theorem for such mappings. The obtained result extends, generalizes and improves many existing contributions in the literature including standard fixed point theorems, fixed point theorems on a metric space endowed with a partial order and fixed point theorems for cyclic mappings.