In this paper, we extend previous work on geographic random forwarding (GeRaF) by considering a more efficient paradigm whereby on/off cycles are exploited and every node can participate to packet relaying, as long as it wakes up during any handshake procedure. The protocol is fully distributed, as routing decisions are made hop by hop based on geographic metrics and using a joint channel acces...

This paper presents and analyzes an integrated, cross-layer protocol for wireless ad hoc networking that utilizes position location (e.g., through an onboard GPS receiver) and jointly performs the operations of network-layer relaying and link-layer ARQbased error control. The protocol is a modified version of the hybrid-ARQ-based intra-cluster geographically-informed relaying (HARBINGER) protoc...

Ingewikkeld beleidsonderzoek kan veel opleveren, maar simpel ook de nodige bijdragen leveren aan beleidsontwikkeling. Bovendien een opstap zijn naar ingewikkelder beleidsonderzoek.

We propose a new data-structure, the generalized randomized k -d forest, or k -d GeRaF, for approximate nearest neighbor searching in high dimensions. In particular, we introduce new randomization techniques to specify a set of independently constructed trees where search is performed simultaneously, hence increasing accuracy. We omit backtracking, and we optimize distance computations, thus ac...

In this paper, we describe ways of enhancing concept mapping tools to facilitate representation and use of superimposed information. Superimposed information refers to new interpretation of existing information and involves working with information at various document granularities (sub-document, complete document, and multi-document). We illustrate our approach by showing how enhanced concept ...

Für viele Anwendungen war das Relationenmodell allerdings zu simpel. Seit etwa 1990 setzten sich in der Forschung objektorientierte, später als Kompromiss objektrelationale Datenbanksysteme durch. Mit Verbreitung des Webs wurden Markup-Sprachen zur Beschreibung von Dokumenten beliebt, die in Form von XML dann auch der nächsten Generation von Datenbanksystemen ein Pseudo-Datenbankmodell lieferte...