A5086872673- Advanced Graph Theory Research
- Limits and Structures in Graph Theory
- Graph theory and applications
- Graph Labeling and Dimension Problems
- graph theory and CDMA systems
- Advanced Topology and Set Theory
- Complexity and Algorithms in Graphs
- Graph Theory and Algorithms
- semigroups and automata theory
- Algorithms and Data Compression
- Digital Image Processing Techniques
- Opinion Dynamics and Social Influence
- Mathematics and Applications
- Interconnection Networks and Systems
- Mathematical and Theoretical Epidemiology and Ecology Models
- Optimization and Packing Problems
- Complex Network Analysis Techniques
- Advanced Numerical Analysis Techniques
- Fullerene Chemistry and Applications
- Computational Geometry and Mesh Generation
- Mathematical Dynamics and Fractals
- Synthesis and Properties of Aromatic Compounds
- Mathematical Approximation and Integration
- Advanced Optimization Algorithms Research
- Data Management and Algorithms
Budapest University of Technology and Economics
2014-2024
Eötvös Loránd University
1992-2021
Hungarian Academy of Sciences
1972-2016
Institute of Automation
2016
Payame Noor University
2014
University of Kashan
2014
Budapest Institute
2000-2009
Ibaraki University
2001-2004
Hitachi (Japan)
2001-2004
Alfréd Rényi Institute of Mathematics
2001
A cyclic ordering of the vertices a k-uniform hypergraph is called hamiltonian chain if any k consecutive in form an edge. For = 2 this same as cycle. We consider several natural questions about new notion. The main result Dirac-type theorem that provides sufficient condition for finding chains hypergraphs with large (k − 1)-minimal degree. If it more than contains chain. © 1999 Wiley & Sons, Inc. J Graph Theory 30: 205–212,
Let be a family of subsets an n -element set. It is called intersecting if every pair its members has non-disjoint intersection. well known that satisfies the inequality | ≤ 2 −1 . Suppose |=2 + i Choose independently with probability p (delete them 1 − ). The new certain probability. We try to maximize this by choosing appropriately. exact maximum determined in paper for some small analogous problem considered families consisting k subsets, but solution obtained only when size exceeds one....
Hierarchical clustering methods like Ward's method have been used since decades to understand biological and chemical data sets. In order get a partition of the set, it is necessary choose an optimal level hierarchy by so-called selection algorithm. 2005, new kind hierarchical was introduced Palla et al. that differs in two ways from method: can be on which no full similarity matrix defined produce overlapping clusters, i.e., allow for multiple membership items clusters. These features are...
Let $t$ be a positive real number. A graph is called \emph{$t$-tough} if the removal of any vertex set $S$ that disconnects leaves at most $|S|/t$ components. The toughness largest for which $t$-tough. minimally $t$-tough and deletion edge from decreases toughness. \emph{chordal} it does not contain an induced cycle length least $4$. We characterize $t$-tough, chordal graphs all $t\le 1/2$. As corollary, characterization interval obtained
In [C. Xue, C. Yerger: Optimal Pebbling on Grids, Graphs and Combinatorics] the authors conjecture that if every vertex of an infinite square grid is reachable from a pebble distribution, then covering ratio this distribution at most $3.25$. First we present such with $3.5$, disproving conjecture. The in above paper also claim to prove any $6.75$. proof contains some errors. We few interesting distributions does not seem cover highlight other difficulties topic.
A cyclic ordering of the vertices a k-uniform hypergraph is called hamiltonian chain if any k consecutive in form an edge. For = 2 this same as cycle. We consider several natural questions about new notion. The main result Dirac-type theorem that provides sufficient condition for finding chains hypergraphs with large (k − 1)-minimal degree. If it more than contains chain. © 1999 Wiley & Sons, Inc. J Graph Theory 30: 205–212,
Let X be an n-element finite set, and 0 are pairs of disjoint k-element subsets (that is, {A1 = B1} {A2 B2} k, A1 \ B1 A2 B2 Define the distance between these by d(f A1;B1 g; f A2; g)=min fj - j + j; jg . Itisknown ([2]) that family all can paired (with one exception if their number is odd) in such a way any two at least k. Here we answer questions arising for distances larger than