The wiki pages about chabots mention that statistical methods, keyword search and precompiled answers are used for the chatbots. But I feel that there should exist different - semantical approach for constructing chatbots. There are formal semantics of natural language (recent results in http://www.springer.com/gp/book/9783319504209) that expresses natural language into lambda calculus and translates those expressions into further logical expressions like deontic logic expressions. And then there is discourse representation theory. So - in essence one can imagine the conversational process as interactive logical inference process in which conversational agent as Belief-Desire-Intention agent strives to achieve some goals by producing texts using formal semantics of natural language and the logical inference (inference control).
So - are there research efforts or research trends along the described lines? Google gives nothing important for joined phrases 'discourse represenation theory and chatbot', etc. But Google is not helpful in many many cases in which scientific endeavours uses completely different keywords. So - I am asking for keywords and maybe some reference works.