EMSO-Definability of Some Languages with Event Structures

Languages of words, trees, and pictures with related event structures are considered. An event structure is defined for a word (tree, picture) from the event structures of individual letters and homogeneous relations between the events of letters on neighboring positions. The main problem considered is the problem of EMSO-definability of two language classes: the class of languages with cyclic event structures and the class of languages with acyclic event structures. Bibliography: 5 titles.