Gyula O.H. Katona – författare

Discrete mathematics, including (combinatorial) number theory and set theory has always been a stronghold of Hungarian mathematics. The present volume honouring Vera Sos and Andras Hajnal contains survey articles (with classical theorems and state-of-the-art results) and cutting edge expository research papers with new theorems and proofs in the area of the classical Hungarian subjects, like extremal combinatorics, colorings, combinatorial number theory, etc. The open problems and the latest results in the papers inspire further research.

The volume is recommended to experienced specialists as well as to young researchers and students.

This book constitutes the thoroughly refereed post-proceedings of the Second International Workshop on Semantics in Databases, held in Dagstuhl Castle, Germany, in January 2001.

The 10 revised full papers presented together with an introduction by the volume editors were carefully selected during two rounds of reviewing. Among the aspects of database semantics discussed are semantic constraints, paraconsistency, logic foundations of databases, ER modeling, type hierarchies, null values, consistency enforcement, logic-based pattern languages, and semantic classification of queries. Among the classes of databases dealt with are deductive databases, relational databases, distributed information systems, and tree-structured data.

Hungarian mathematics has always been known for discrete mathematics, including combinatorial number theory, set theory and recently random structures, combinatorial geometry as well.

The recent volume contains high level surveys on these topics with authors mostly being invited speakers for the conference "Horizons of Combinatorics" held in Balatonalmadi, Hungary in 2006. The collection gives a very good overview of recent trends and results in a large part of combinatorics and related topics, and offers an interesting reading for experienced specialists as well as to young researchers and students.

Discrete mathematics and theoretical computer science are closely linked research areas with strong impacts on applications and various other scientific disciplines. Both fields deeply cross fertilize each other. One of the persons who particularly contributed to building bridges between these and many other areas is László Lovász, a scholar whose outstanding scientific work has defined and shaped many research directions in the last 40 years. A number of friends and colleagues, all top authorities in their fields of expertise and all invited plenary speakers at one of two conferences in August 2008 in Hungary, both celebrating Lovász’s 60th birthday, have contributed their latest research papers to this volume. This collection of articles offers an excellent view on the state of combinatorics and related topics and will be of interest for experienced specialists as well as young researchers.