The Semantic Web is based on accessing and reusing RDF data from many different sources, which one may assign different levels of authority and credibility. Existing Semantic Web query languages, like SPARQL, have targeted the retrieval, combination and reuse of facts, but have so far ignored all aspects of meta knowledge, such as origins, authorship, recency or certainty of data, to name but a few. In this paper, we present an original, generic, formalized and implemented approach for managing many dimensions of meta knowledge, like source, authorship, certainty and others. The approach re-uses existing RDF modeling possibilities in order to represent meta knowledge. Then, it extends SPARQL query processing in such a way that given a SPARQL query for data, one may request meta knowledge without modifying the query proper. Thus, our approach achieves highly flexible and automatically coordinated querying for data and meta knowledge, while completely separating the two areas of concern.

This volume contains those research papers presented at the Second International Conference on Tests and Proofs (TAP 2008) that were not included in the main conference proceedings. TAP was the second conference devoted to the convergence of proofs and tests. It combines ideas from both areas for the advancement of software quality. To prove the correctness of a program is to demonstrate, through impeccable mathematical techniques, that it has no bugs; to test a program is to run it with the expectation of discovering bugs. On the surface, the two techniques seem contradictory: if you have proved your program, it is fruitless to comb it for bugs; and if you are testing it, that is surely a sign that you have given up on any hope of proving its correctness. Accordingly, proofs and tests have, since the onset of software engineering research, been pursued by distinct communities using rather different techniques and tools. And yet the development of both approaches leads to the discovery of common issues and to the realization that each may need the other. The emergence of model checking has been one of the first signs that contradiction may yield to complementarity, but in the past few years an increasing number of research efforts have encountered the need for combining proofs and tests, dropping earlier dogmatic views of their incompatibility and taking instead the best of what each of these software engineering domains has to offer. The first TAP conference (held at ETH Zurich in February 2007) was an attempt to provide a forum for the cross-fertilization of ideas and approaches from the testing and proving communities. For the 2008 edition we found the Monash University Prato Centre near Florence to be an ideal place providing a stimulating environment. We wish to sincerely thank all the authors who submitted their work for consideration. And we would like to thank the Program Committee members as well as additional referees for their great effort and professional work in the review and selection process. Their names are listed on the following pages. In addition to the contributed papers, the program included three excellent keynote talks. We are grateful to Michael Hennell (LDRA Ltd., Cheshire, UK), Orna Kupferman (Hebrew University, Israel), and Elaine Weyuker (AT&T Labs Inc., USA) for accepting the invitation to address the conference. Two very interesting tutorials were part of TAP 2008: "Parameterized Unit Testing with Pex" (J. de Halleux, N. Tillmann) and "Integrating Verification and Testing of Object-Oriented Software" (C. Engel, C. Gladisch, V. Klebanov, and P. Rümmer). We would like to express our thanks to the tutorial presenters for their contribution. It was a team effort that made the conference so successful. We are grateful to the Conference Chair and the Steering Committee members for their support. And we particularly thank Christoph Gladisch, Beate Körner, and Philipp Rümmer for their hard work and help in making the conference a success. In addition, we gratefully acknowledge the generous support of Microsoft Research Redmond, who financed an invited speaker.

Es wird erklärt, was ein Beschreibungsmodell ist, wie IT-Sicherheitsmodelle grundsätzlich aufgebaut sind und welchem Zweck sie dienen. Zur Illustration werden vier verschiedene IT-Sicherheitsmodelle vorgestellt, die historisch zu unterschiedlichen Zeiten entstanden sind. Sie passen zu vier verschiedenen typischen Anwendungsumgebungen und charakterisieren die zugehörigen Sicherheitsanforderungen. Vorgestellt werden das Bell-LaPadula-Modell zum Vertraulichkeitsschutz in hierarchischen Institutionen, das Clark-Wilson-Modell zum Integri-tätsschutz von Geschäftsanwendungen, das Chinese-Wall-Modell zum Konkurrentenschutz von Unternehmen und das Gleichgewichtsmodell zum Schutz verbindlichen Handelns im offenen Internet.

Ziel des Verbundprojektes 3D-RETISEG ist es, ein optimiertes echtzeitfähiges Soft- und Hardwarepaket zur 2D/3D-Segmentierung und Klassifizierung basierend auf hierarchischen Inselstrukturen, und zur schnellen Volumenvisualisierung sehr großer Volumendaten aus komprimierten Datensätzen zu entwickeln. Die Entwicklungen sollen in konkreten Anwendungsfällen der Forschung und der Wirtschaft als marktreifes Modul in das Softwarepaket VGStudioMax integriert werden. In der Medizin, speziell bei der Segmentierung von Volumendatensätzen, die durch unterschiedliche Tomographietechniken (z.B. CT und MRI) erzeugt werden, liefern zweidimensionale Verfahren häufig eine unzureichende Qualität aufgrund der anisotropen Berücksichtigung der Rauminformationen. Bisher entwickelte dreidimensionale Verfahren sind, neben der der schlechten Verfügbarkeit ihrer Implementierungen, häufig nur für bestimmte Fragestellungen dediziert und daher für andere Anwendungsfälle schlecht adaptierbar. Weiterhin benötigen Verfahren, die gute Ergebnisse liefern, meist eine hohe Laufzeit. Dies ist aber speziell in medizinischen Anwendungen von großem Nachteil, da hier die Qualität der Ergebnisse in letzter Instanz von einem Experten beurteilt wird. Damit das Ergebnis schnell zu benutzerdefinierten Optimierungen durch Veränderung der Verfahrensparameter zur Verfügung steht, sollte ein Verfahren nur sehr kurze Rechenzeiten benötigen. Weist ein Verfahren eine geringe Laufzeit auf, so kann es außerdem intra-operativ eingesetzt werden. Der hier im Projekt verwendete 3D-Color-Structure-Code verspricht, ein besseres und generisches Verfahren zu ermöglichen.

In this paper we describe a network for distributing personalized information within a pervasive university. We discuss the system architecture of our Bluetooth-based CampusNews-system, both, from the administrator and the user viewpoint. We furthermore present first statistical data about the usage of the partial installation at the Koblenz campus together with an outlook to future work.