Ringi Kim (김린기), The strong clique number of graphs with forbidden cycles
Room B232 IBS (기초과학연구원)The strong clique number of a graph
10 events found.
Seminars and Colloquiums
Pascal Gollin, Disjoint dijoins for classes of dibonds in finite and infinite digraphs
Room B232 IBS (기초과학연구원)A dibond in a directed graph is a bond (i.e. a minimal non-empty cut) for which all of its edges are directed to a common side of the cut. A famous theorem of Lucchesi and Younger states that in every finite digraph the least size of an edge set meeting every dicut equals the maximum …
Casey Tompkins, Saturation problems in the Ramsey theory of graphs, posets and point sets
Room B232 IBS (기초과학연구원)In 1964, Erdős, Hajnal and Moon introduced a saturation version of Turán's classical theorem in extremal graph theory. In particular, they determined the minimum number of edges in a
Sang-il Oum (엄상일), Survey on vertex-minors
Room B232 IBS (기초과학연구원)For a vertex v of a graph G, the local complementation at v is an operation to obtain a new graph denoted by G*v from G such that two distinct vertices x, y are adjacent in G*v if and only if both x, y are neighbors of v and x, y are non-adjacent, or at least one …
Seunghun Lee (이승훈), Leray numbers of complexes of graphs with bounded matching number
Room B232 IBS (기초과학연구원)Given a graph
Eun Jung Kim (김은정), Twin-width: tractable FO model checking
Room B232 IBS (기초과학연구원)Inspired by a width invariant defined on permutations by Guillemot and Marx , we introduce the notion of twin-width on graphs and on matrices. Proper minor-closed classes, bounded rank-width graphs, map graphs,
O-joung Kwon (권오정), Mim-width: a width parameter beyond rank-width
Room B232 IBS (기초과학연구원)Vatshelle (2012) introduced a width parameter called mim-width. It is based on the following cut function : for a vertex partition (A,B) of a graph, the complexity of this partition is computed by the size of a maximum induced matching of the bipartite subgraph induced by edges between A and B. This parameter naturally extends …
Hong Liu (刘鸿), Asymptotic Structure for the Clique Density Theorem
Room B232 IBS (기초과학연구원)The famous Erdős-Rademacher problem asks for the smallest number of r-cliques in a graph with the given number of vertices and edges. Despite decades of active attempts, the asymptotic value of this extremal function for all r was determined only recently, by Reiher . Here we describe the asymptotic structure of all almost extremal graphs. …
Huy-Tung Nguyen, The average cut-rank of graphs
Room B232 IBS (기초과학연구원)The cut-rank of a set X of vertices in a graph G is defined as the rank of the X×(V(G)∖X) matrix over the binary field whose (i,j)-entry is 1 if the vertex i in X is adjacent to the vertex j in V(G)∖X and 0 otherwise. We introduce the graph parameter called the average cut-rank …
Jiseung Kim (김지승), Hardness and concrete security in cryptography
Room B232 IBS (기초과학연구원)Computationally hard problems have been widely used to construct cryptographic primitives such as encryptions, digital signatures. For example, provably secure primitives are based on a reduction from the hardness problems. However, the concrete instantiation of primitives does not follow the results of hardness problems due to its efficiency. In this talk, we introduce cryptographic hardness …