Refine
Year of publication
- 2010 (18) (remove)
Document Type
- Part of Periodical (17)
- Study Thesis (1)
Has Fulltext
- yes (18) (remove)
Keywords
- ontology (2)
- Annotationsmodell (1)
- Ausstellung (1)
- Authentisierung (1)
- Common Annotation Framework (1)
- Context-aware processes (1)
- Core Ontology on Multimedia (1)
- Datenschutz (1)
- Description Logic (1)
- Description Logics (1)
Institute
- Fachbereich 4 (18) (remove)
In dieser Arbeit wird ein Mehrbenutzer-Annotationssystem namens myAnnotations vorgestellt, das mit Hilfe von sogenannten "Shared In-situ Problem Solving" Annotationen auf beliebigen Webseiten kollaborative Lern- und Arbeitsszenarien unterstützt. Hierbei wird insbesondere auf die Einsatzmöglichkeiten von "Shared In-situ Problem Solving" Annotationen beim kollaborativen Bearbeiten eines Textes und bei kollaborativen Lernerfolgskontrollen eingegangen.
Hybrid automata are used as standard means for the specification and analysis of dynamical systems. Several researches have approached them to formally specify reactive Multi-agent systems situated in a physical environment, where the agents react continuously to their environment. The specified systems, in turn, are formally checked with the help of existing hybrid automata verification tools. However, when dealing with multi-agent systems, two problems may be raised. The first problem is a state space problem raised due to the composition process, where the agents have to be parallel composed into an agent capturing all possible behaviors of the multi-agent system prior to the verification phase. The second problem concerns the expressiveness of verification tools when modeling and verifying certain behaviors. Therefore, this paper tackles these problems by showing how multi-agent systems, specified as hybrid automata, can be modeled and verified using constraint logic programming(CLP). In particular, a CLP framework is presented to show how the composition of multi-agent behaviors can be captured dynamically during the verification phase. This can relieve the state space complexity that may occur as a result of the composition process. Additionally, the expressiveness of the CLP model flexibly allows not only to model multi-agent systems, but also to check various properties by means of the reachability analysis. Experiments are promising to show the feasibility of our approach.
Conventional security infrastructures in the Internet cannot be directly adopted to ambient systems, especially if based on short-range communication channels: Personal, mobile devices are used and the participants are present during communication, so privacy protection is a crucial issue. As ambient systems cannot rely on an uninterrupted connection to a Trust Center, certiffed data has to be veriffed locally. Security techniques have to be adjusted to the special environment. This paper introduces a public key infrastructure (PKI) to provide secure communication channels with respect to privacy, confidentiality, data integrity, non-repudiability, and user or device authentication. It supports three certiffcate levels with a different balance between authenticity and anonymity. This PKI is currently under implementation as part of the iCity project.
Dieses Dokument schlägt ein Konzept für eine Personal Key Infrastruktur in iCity vor. Über ein Trust Center (TC) ausgestellte Zertiffkate gewährleisten einen sicheren Schlüsselaustausch mit nachweisbarer Authentisierung des Kommunikationspartners, Abhörsicherheit sowie Unverf älschtheit und Nachweisbarkeit der Nachrichten. Das gemeinsam vertrauensw ürdige TC muss während der Kommunikation nicht erreichbar sein. Es erhält lediglich öffentliche Informationen. Das Konzept stellt mehrere Sicherheitsstufen vor, die sichere Identiffkation und Anonymität unterschiedlich gewichten.
The novel mobile application csxPOI (short for: collaborative, semantic, and context-aware points-of-interest) enables its users to collaboratively create, share, and modify semantic points of interest (POI). Semantic POIs describe geographic places with explicit semantic properties of a collaboratively created ontology. As the ontology includes multiple subclassiffcations and instantiations and as it links to DBpedia, the richness of annotation goes far beyond mere textual annotations such as tags. With the intuitive interface of csxPOI, users can easily create, delete, and modify their POIs and those shared by others. Thereby, the users adapt the structure of the ontology underlying the semantic annotations of the POIs. Data mining techniques are employed to cluster and thus improve the quality of the collaboratively created POIs. The semantic POIs and collaborative POI ontology are published as Linked Open Data.
Femto is a programming environment designed to run on an ATmega based computing platform with VGA video output and a PS/2 keyboard interface. It consists of a simple text editor and an interpreter. With Femto it is possible to write and run small programs directly on the microcontroller. The interpreted language is called Femtoscript and is similar to Javascript. It was developed as part of this project. The interpreter is written in C and can be ported to other platforms with relatively small effort.
Ontologies play an important role in knowledge representation for sharing information and collaboratively developing knowledge bases. They are changed, adapted and reused in different applications and domains resulting in multiple versions of an ontology. The comparison of different versions and the analysis of changes at a higher level of abstraction may be insightful to understand the changes that were applied to an ontology. While there is existing work on detecting (syntactical) differences and changes in ontologies, there is still a need in analyzing ontology changes at a higher level of abstraction like ontology evolution or refactoring pattern. In our approach we start from a classification of model refactoring patterns found in software engineering for identifying such refactoring patterns in OWL ontologies using DL reasoning to recognize these patterns.
In dieser Arbeit wird ein Datenmodell für Shared Annotations vorgestellt. Basierend auf einem bereits existierenden Datenmodell für Annotationen, wird dieses erweitert um die Möglichkeit der Modellierung von Shared Annotations. Daraufhin werden Funktionen von Shared Annotations erläutert, die über das neue Annotationsmodell möglich sind.
