In this paper we give an overview of context-aware middleware platforms. They are characterized in terms of properties such as communication, context management and adaptation. We present a description of different platforms and their properties. key words: context-awareness, middleware platform, pervasive computing.

We consider conditional context-free grammars that generate languages of nite index. Thereby, we solve an open problem stated in Dassow and PP aun's monograph on regulated rewriting. Moreover, we show that conditional context-free languages with context-free conditions of nite index are more powerful than conditional context-free languages with regular conditions of nite index. Furthermore, we ...

We study k-prefix-free, k-suffix-free and k-infix-free languages that generalize prefix-free, suffix-free and infix-free languages by allowing marginal errors. For example, a string x in a k-prefix-free language L can be a prefix of up to k different strings in L. Namely, a code (language) can allow some marginal errors. We also define finitely prefix-free languages in which a string x can be a...

The family of one-rule grid semi-Thue systems, introduced by Alfons Geser, is the family of one-rule semi-Thue systems such that there exists a letter c that occurs as often in the left-hand side as the right-hand side of the rewriting rule. We prove that for any one-rule grid semi-Thue system S, the set S(w) of all words obtainable from w using repeatedly the rewriting rule of S is a construct...

Pregroups had been conceived as an algebraic tool to recognize grammatically well-formed sentences in natural languages [3]. Here we wish to use pregroups to recognize well-formed chords of pitches, for a given definition of those chords. We show how a judicious choice of basic and simple types allows a context-free grammatical description. Then we use the robustness property to extend the set ...

For any context-free grammar, we build a transition diagram, that is, a finite directed graph with labeled arcs, which describes the work of the grammar. This approach is new, and it is different from previously known graph models. We define the concept of proper walk in this transition diagram and we prove that a word belongs to a given context-free language if and only if this word can be obt...

There is no free ride in enhancing context-awareness of artifacts as artifacts lack the ability to (re-) negotiate the meaning of particular situations. We therefore argue that research in context-awareness should be complemented by orthogonal research in what we call context-transparency.

We examine the relationship between context engines and content management systems, showing by means of an example application how these should mutually interact with each other to ensure the timely delivery of relevant information. We show how a content management system can use context information to enrich its functionality and also how a general and abstract approach to content management c...

This paper investigates whether surprisal theory can account for differential processing difficulty in the NP-/S-coordination ambiguity in Dutch. Surprisal is estimated using a Probabilistic Context-Free Grammar (PCFG), which is induced from an automatically annotated corpus. We find that our lexicalized surprisal model can account for the reading time data from a classic experiment on this amb...

In this paper, we present a hybrid grammar formalism designed to learn structured models of natural iconic gesture performances that allow for compressed representation and robust recognition. We analyze a dataset of iconic gestures and show how the proposed Featurebased Stochastic Context-Free Grammar (FSCFG) can generalize over both structural and feature-based variations among different gest...