We overview some perspectives on the concept of servicebased computing, and discuss the motivation of a small set of modeling abstractions for expressing and analyzing service based systems, which have led to the design of the Conversation Calculus. Distinguishing aspects of the Conversation Calculus are the adoption of a very simple, context sensitive, local message-passing communication mecha...

This paper presents a new hierarchical mode segmentation of the observed driving behavioral data based on the multi-level abstraction of the underlying dynamics. By synthesizing the ideas of a feature vector definition revealing the dynamical characteristics and an unsupervised clustering technique, the hierarchical mode segmentation is achieved. The identified mode can be regarded as a kind of...

Propagating scattered context grammars, introduced in [3], represent an important type of semi-parallel rewriting systems. Since their introduction, however, the exact relationship of the family of languages they generate to the family of context-sensitive languages is unknown. The language family generated by these grammars is included in the family of context-sensitive languages; on the other...

Theoretical results on HTN planning are mostly related to the plan existence problem. In this paper, we study the structure of the generated plans in terms of the language they produce. We show that such languages are always context-sensitive. Furthermore we identify certain subclasses of HTN planning problems which generate either regular or context-free languages. Most importantly we have dis...

We consider the language consisting of all words such that it is possible to obtain the empty word by iteratively deleting powers. It turns out that in the case of deleting squares in binary words this language is regular, and in the case of deleting squares in words over a larger alphabet the language is not regular. However, for deleting squares over any alphabet we find that this language ca...

Let Q be the set of all primitive words over a finite alphabet having at least two letters. In this paper, we study the language D(1) of all non-overlapping (d-primitive) words, which is a proper subset of Q. We show that D(1) is a contextsensitive langauage but not a deterministic context-free language. Further it is shown that [D(1)]n is not regular for n ≥ 1. key words: primitive word, non-o...

Context-sensitive grammars in which each rule is of the forln aZfl-~ (-*Tfl are acyclic if the associated context-free grammar with the rules Z ~ 3' is acyclic. The problem whether an intmt string is in the language generated by an acyclic context-sensitive grammar is NP-conlplete.

By introducing the Regular Membership Constraint, Gilles Pesant pioneered the idea of basing constraints on formal languages. The paper presented here is highly motivated by this work, taking the obvious next step, namely to investigate constraints based on grammars higher up in the Chomsky hierarchy. We devise an arc-consistency algorithm for context-free grammars, investigate when logic combi...

This paper presents a novel approach to integrate mildly context sensitive grammar in the context of pre-ordering for machine translation. We discuss the linguistic insights available in this grammar formalism and use it to develop a pre-ordering system. We show that mildly context sensitive grammar proves to be beneficial over context free grammar, which facilitates better reordering rules. Fo...

As shown by Michaelis (2001a,b), Stablerian Minimalist Grammars (MGs) (Stabler 1997b, 1998, 2008) belong among the class of mildly context-sensitive grammar formalisms as, e.g., characterized in Joshi et al. 1991. Crucially, mild context-sensitivity depends on what may—somewhat loosely—be referred to as resource-sensitivity, i.e., strictly limited combinability of syntactic objects. Within MGs,...