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In this chapter, we evaluate the feasibility of intelligent and distributed control of shared resources in user-managed networks. The user-managed network paradigm has become possible with the advent of broadband wireless networking technologies such as IEEE 802.11. [ABSTRACT FROM AUTHOR]

The high cost in acquiring data for populating Geographic Information Systems (GIS) was, in the past, one of the main obstacles for its wide diffusion. The Internet created a huge network where users, institutions and organizations can easily share information. However, if on one hand, this interchange offers a lot of benefits, on the other hand it generates the need to address the heterogeneities among the information obtained from distinct sources. [ABSTRACT FROM AUTHOR]

In open networked systems a varying number of nodes interact each other just on the basis of their own independent ontologies and of knowledge discovery requests submitted to the network. Ontology matching techniques are essential to enable knowledge discovery and sharing in order to determine mappings between semantically related concepts of different ontologies. In this paper, we describe the H-Match algorithm and related techniques for performing matching of independent ontologies in open networked systems. A key feature of H-Match is that it can be dynamically configured for adaptation to the semantic complexity of the ontologies to be compared, where the number and type of ontology features that can be exploited during the matching process is not known in advance as it is embedded in the current knowledge request. Furthermore, this number can vary, also for the same ontologies, each time a new matching execution comes into play triggered by a knowledge request. We describe how H-Match enforces this capabilities through a combination of syntactic and semantic techniques as well as through a set of four matching models, namely surface, shallow, deep, and intensive. Then, we describe the application of H-Match and its implementation for knowledge discovery in the framework of the Helios peer-based system. Finally, we present experimental results of using H-Match on different test cases, along with a discussion on precision and recall. [ABSTRACT FROM AUTHOR]

Music description is nowadays considered an important matter in Information and Communication Technology. The encoding formats commonly accepted and employed are often characterized by a partial view of the whole problem: they describe music data or metadata for score, audio tracks, computer performances of music pieces, but they seldom encode all these aspects together. In this paper, we present the MX formalism that aims to address this limitation of the existing formats, by providing a Semantic Web compatible representation of music information in terms of structural and semantic features, by means of XML and OWL. [ABSTRACT FROM AUTHOR]

Autonomous off-road navigation is central to several important applications of unmanned ground vehicles. This requires the ability to detect obstacles in vegetation. We examine the prospects for doing so with scanning ladar and with a linear array of 2.2 GHz micro-impulse radar transceivers. For ladar, we summarize our work to date on algorithms for detecting obstacles in tall grass with single-axis ladar, then present a simple probabilistic model of the distance into tall grass that ladar-based obstacle detection is possible. This model indicates that the ladar "penetration depth" can range from on the order of 10 cm to several meters, depending on the plant type. We also present an experimental investigation of mixed pixel phenomenology for a time-of-flight, SICK ladar and discuss briefly how this bears on the problem. For radar, we show results of applying an existing algorithm for multi-frequency diffraction tomography to a set of 45 scans taken with one sensor translating laterally 4 cm/scan to mimic a linear array of transceivers. This produces a high resolution, 2-D map of scattering surfaces in front of the array and clearly reveals a large tree trunk behind over 2.5 m of thick foliage. Both types of sensor warrant further development and exploitation for this problem. [ABSTRACT FROM AUTHOR]