Home > Search Results: Onduš, Daniel
Search:
Search Tips :: Advanced Search
Search collections:
Sort by: Display results: Output format:
National Repository of Grey Literature 2 records found  Search took 0.00 seconds. 
Partial representation extension for subclasses of interval graphs
 Onduš, Daniel ; Kratochvíl, Jan (advisor) ; Jelínek, Vít (referee)
The problem of extending partial representations for an interval graph asks, whether it is possible to extend a given representation of some vertices to a valid representation of the entire graph. In this thesis we extend the recent result of Klavík et al. who proved REPEXT can be decided for proper and unit interval graphs in polynomial time. We describe properties of PI± and U± graphs and their representations and present algorithms deciding REPEXT for these classes in polynomial time. In the process, we characterize relations between the K1,3's in a graph and show that we can decide the open vertex of every K1,3. We also define notions of representation of the same order type and locally similar representations as well as intervals forced and locally forced to be closed (open) that are essential for extending partial representations when multiple types of intervals can occur in the same representation. We characterize intervals forced and locally forced to be closed (open) in a U± graph using integer gaps in the pre-representation and we construct lower bounds for the rightmost endpoint of a component in polynomial time.
Detailed record
Three-Line Latin Rectangles and Associativity
 Onduš, Daniel ; Drápal, Aleš (advisor) ; Vojtěchovský, Petr (referee)
This thesis deals with properties of permutations and three-line latin rectan- gles. In the first part it offers solutions to several combinatorial problems and derrives formula for enumeration of three-line latin rectangles and its simplifica- tion based on articles by J. Riordan, but unlike Riordan's articles, without use of generating functions. In the second part it shows algebraic properties of permu- tation conjugation. Furthermore it provides an algorithm that constructs set of permutations commuting with a given permutation and enumerates orbits of the set of three-line latin rectangles when conjugating by the group of permutations Sn for small n.
Detailed record

Interested in being notified about new results for this query?
Subscribe to the RSS feed.
Digital Repository :: Search :: Submit :: Personalize :: Help
Powered by Invenio v1.1.2
Maintained by admin.invenio@techlib.cz
This site is also available in the following languages:
Česky  English