"255337" . . "Dualities in full homomorphisms" . . "Ball, Richard N." . . . . "1" . "31" . . "Dualities in full homomorphisms" . "RIV/00216208:11320/10:10081043" . "000271971000011" . "11320" . . . "graphs; homomorphism; Duality"@en . "[17386822B262]" . . . . "Ne\u0161et\u0159il, Jaroslav" . . "European Journal of Combinatorics" . . . "Pultr, Ale\u0161" . "P(1M0545), Z(MSM0021620838)" . "3"^^ . "RIV/00216208:11320/10:10081043!RIV11-MSM-11320___" . "In this paper we study dualities of graphs and, more generally, relational structures with respect to full homomorphisms, that is, mappings that are both edge- and non-edge-preserving. The research was motivated, a.o., by results from logic (concerning first order definability) and Constraint Satisfaction Problems. We prove that for any finite set of objects B (finite relational Structures) there is a finite duality with B to the left. It appears that the surprising richness of these dualities leads to interesting problems of Ramsey type: this is what we explicitly analyze in the simplest case of graphs."@en . "US - Spojen\u00E9 st\u00E1ty americk\u00E9" . . "0195-6698" . "2"^^ . . "14"^^ . "Dualities in full homomorphisms"@en . . "Dualities in full homomorphisms"@en . "In this paper we study dualities of graphs and, more generally, relational structures with respect to full homomorphisms, that is, mappings that are both edge- and non-edge-preserving. The research was motivated, a.o., by results from logic (concerning first order definability) and Constraint Satisfaction Problems. We prove that for any finite set of objects B (finite relational Structures) there is a finite duality with B to the left. It appears that the surprising richness of these dualities leads to interesting problems of Ramsey type: this is what we explicitly analyze in the simplest case of graphs." . .