This thesis deals with approximation algorithms for the Maximum Independent Set and the Minimum Hitting Set problems on hypergraphs. As a hypergraph is a generalization of a graph, the question is whether the best known approximations on graphs can be ...

One of the research areas of great importance in Computer Science is the study of the semantics of concurrent reactive systems. These are systems that compute by interacting with their environment, and typically consist of several parallel components, ...

Structural Operational Semantics (SOS) is one of the most natural ways for providing programming languages with a formal semantics. Results on the meta-theory of SOS typically (but not solely) say that if the inference rules used in writing the semantic ...

Vincular and covincular patterns are generalizations of classical patterns allowing restrictions on the indices and values of the occurrences in a permutation. In this paper we study the integer sequences arising as the enumerations of permutations ...

In the recent years, formal modeling and verification of realtime systems have become very important. Difficult-to-use modeling languages and inefficient analysis tools are the main obstacles to use formal methods in this domain. Timed actor model is ...

This dissertation is composed of two parts. In the first part, performance evaluation and verification of safety properties are provided for real-time actors. Recently, the actor-based language, Timed Rebeca, was introduced to model distributed and ...

The aim of General Game Playing (GGP) is to create intelligent agents that automatically learn how to play many different games at an expert level without any human intervention. One of the main challenges such agents face is to automatically learn ...