Labeled unranked trees are used as a model of XML documents, and logical languages for them have been studied actively over the past several years. Such logics have different purposes: some are better suited for extracting data, some for expressing navigational properties, and some make it easy to relate complex properties of trees to the existence of tree automata for those properties. Furthermore, logics differ significantly in their model-checking properties, their automata models, and their behavior on ordered and unordered trees. In this talk I survey logics for unranked trees.

Научная биография Леонида Либкина

Leonid Libkin has recently been appointed a Marie Curie Chair at the University of Edinburgh. He is currently a Professor of Computer Science at the University of Toronto, and prior to joining Toronto in 2000 he was a member of research staff in the Computing Sciences Research Center at Bell Laboratories in Murray Hill. He received his MSc degree in Moscow, Russia, and his PhD from the University of Pennsylvania in 1994. His research interests are in the areas of databases and applications of logic in computer science; in the past he also worked in lattice theory and universal algebra. He has (co)authored 3 books and over 120 technical papers. He was the recepient of Premier's Research Excellence Award in 2001, and three best paper awards. He has given a dozen invited conference talks, has served on over 25 program committees, three of which he chaired, and is serving on several editorial boards.