Semantic Web Engineering

"The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation" (Tim Berners-Lee et al). Following the explosive initial growth of the Web, we are faced now with a vast universe of more or less organized information resources.

Databases play a crucial role in this universe. Beyond the billion of static Web pages indexed by search engines, there is a "Deep Web" of database contents that is not indexed due to its dynamically generated responses. It is estimated that the Deep Web exceeds the commonly defined World-Wide Web by a factor of 500 in data volume (source: www.completeplanet.com).

The course is subdivided into four parts. After a brief introduction, case studies are investigated, with emphasis on data intensive scientific applications, in particular Grid and geo services. Next, Web Services and the Semantic Web are introduced by inspecting the pertaining standards. The third part is dedicated to selected database concepts and techniques which contribute to the quest of efficiently adding more semantics to the Web.

Goal is to make students familiar with the state of the art in Web-enabled information systems so that they will be successful database/Internet professionals in IT industry or, alternatively, have a sound knowledge base to specialize towards a scientific career in the field.

News

see the course mailing list:

Slides

Introduction: [ introduction | Web Services ]
Raster Services
Web Engineering: [ XML, DTD, XML Schema | SOAP | SOAP revisited by Ryan | WSDL | UDDI | UDDI criticism | REST | AJAX | Web Services wrapup ]
Semantic Web: [ introduction | RDF | Ontologies | Daml+Oil+Owl | logics refresher | OMDoc overview | Logic | Semantics & Web services ]
Outlook: [ Corporate knowledge management | Where to go? | Wrapup ]

Project

Projects are embedded into our work on geo service standardization and the implementation of these standards. Consequently, specifications heavily make use of UML and XML with XML Schema, Java (servlets), JavaScript, AJAX, etc., in combination with further appropriate tools.
A core of tasks is common to all projects: Understanding the specifications sufficiently, implement, document, and demo them. Demonstration data will be provided.

Topics:

the WCPS language as a WPS
Comprehensive PetaScope performance evaluation
WCS 2.0 draft (implementation & test & demo; incl. XPath, WSDL)
Formal model of an extended WCS
A Web-based, platform independent, cross-dimensional raster visualization toolkit
Semantic Description (Catalogue) for WCPS Services and Data
This is to investigate how to describe a WCPS service within a semantic web services framework so that other semantically-described geospatial web services can connect to it. .i.e. writing a OWL-S for WCPS. This may first involve investigating some "established" geopatial data/serivices RDF/Ontology, establishing how useful they are and whether there is a need to extend/restructure them, and then, describing a WCPS services and data within such a framework.
On the other hand, this same topic can be viewed as establishing an RDF/ontology for only WCPS services and data, and implementing a catalogue for them.
Semantic Description (Catalogue) for WPS Services and Data
This is the same as above, but the focus of this will be on WPS. My motivation for suggesting this topic is that in some WCPS query decomposition, some the orchestration engine my want to pass some operations to a WPS to execute. In this project, the semantics of the operations of WCPS query will need to be described in a RDF together with the semantics of WPS.
On-the-fly deployment of BPEL scripts for orchestrating geopsatial web services
Currently, to execute a BPEL script, one has to set up a deployment infrastructure on the server. Also, there is the problem of orchestrating OGC web services using BPEL (to which a number of solutions has been proposed). This project thus will attempt to address the following problem but with special emphasis on WCPS. The goal here is that, one should be able to upload a BPEL script (for orchestrating OGC services) from a browser to a server, and the server should be able to execute it.
WCS 2.0
The OGC Web Coverage Service (WCS) is a standard for basic functionality to access large, multi-dimensional geo raster data. Currently it is being reworked completely by our group for a version 2.0 which has more compatibility with other OGC standards and is easier to understand. A draft specification is already available. Goal of this project is to develop and fine-tune the GML schema and to implement a WCS server. This will be based on the existing petascope implementation which already encompasses a WCS 1.1.2 and further interfaces. Feasibility of the implementation is to be shown by running the service on top of our demo database, EarthLook. The deproject must be completed by the end of November to allow for presenting the results to the OGC standardizationbody for voting on the new standard. The final report, however, can be submitted by the end of the semester.

The visible human as a web service
The Visible Human is a 3-D tomogram of a human body available for research in the life sciences. Many services have been established using this data set, including this one. Goal of this project is to import these data into our rasdaman database and offer it via an interactive Web service in the spirit of EarthLook to show feasiblity of the WCPS geo service standard for life science applications. Notably, functionality should go distinctly beyond mere slicing along the x/y/z axis. By inspecting other services it is expected that new, advanced functions will be developed as queries, such as slicing in any angle, and implemented using current Web technology like JavaScript.

Further topics can be negotiated - contact me if you have a cool idea!

A project consists of several phases (due dates announced during first class unit):

phase 1: source material evaluation
deliverable: report (~5 pages)
phase 2: specification
deliverable: specification document; should normally include the sections: overview; service specification (including justification of features selected, in case of a subset); architecture; interfaces; demonstration scenarios (including sample requests).
phase 3: implementation
deliverable: documented code, ready for installation at some other place; individual handover appointments will be arranged.
phase 4: presentation and final report
deliverable: presentation in class (~20min), including live demonstration, and final report (will be based on the specification document, but extend it with a description and discussion of the results obtained).

Individual deviations might be possible, due to the individuality of the projects. If you want to deviate then agree with your supervisor until the end of phase 1 at the latest.

Grading

...will be done as announced in class, see 1st slide set.

Literature

Web Services:
- Ethan Cerami: Web Services Essentials, O'Reilly, February 2002, ISBN: 0-596-00224-6 (free Safari reading, accessible from Jacobs campus only)
- Jason Hunter, Wiliam Crawford: Java Servlet Programming, O'Reilly, April 2001, ISBN: 0-596-00040-5
Web:
- James Gillies, Robert Cailliau: How the Web was born: the story of the World Wide Web. Oxford University Press, 2000.
  history facets about the WWW
- Janet Abbate: Inventing the Internet.
  history facets about the Internet
- Robert E. Molyneux: The Internet under the hood: an introduction to network technologies for information professionals. Westport, Conn.: Libraries Unlimited, 2003.
  a condensed visit to the lower IP stack elements
- Jeffrey Xu Yu [et al.] (eds.): Advanced Web technologies and applications.. 5th Asia-Pacific Web Conference, APWeb 2004, Hangzhou, China, April 14-17, 2004, LNCS 3007, Springer-Verlag, 2004.

Links

[Semantic] Web Service Conferences:
- Liang-Jie Zhang, Mario Jeckle (eds.): Web services. European conference, ECOWS 2004, Erfurt, Germany, September 27-30, 2004, LNCS 3250, Springer, 2004.
- Sheila A. McIlraith, Dimitris Plexousakis, Frank van Harmelen (eds.): The Semantic Web--ISWC 2004. Third International Semantic Web Conference, Hiroshima, Japan, November 7-11, 2004, LNCS 3298, Springer-Verlag, 2004.
- Christoph Bussler [et al.] (eds.)The Semantic Web : research and applications. First European Semantic Web Symposium, ESWS 2004, Heraklion, Crete, Greece, May 10-12, 2004, LNCS 3053, Springer, 2004.
- Christoph Bussler [et al.] (eds.): Web information systems. WISE 2004 International Workshops, Brisbane, Australia, November 22-24, 2004, LNCS 3307, Springer, 2004.
Web Database Conferences
- Karl Aberer, Manolis Koubarakis, Vana Kalogeraki (eds.): Databases, information systems, and peer-to-peer computing. First international workshop, DBISP2P 2003: Berlin, Germany, September 7-8, 2003, LNCS 2944, Springer, 2004.
Grid Service Conferences:
- Mario Jeckle, Ryszard Kowalczyk, Peter Braun (eds.): Grid services engineering and management. first international conference, GSEM 2004, Erfurt, Germany, September 27-30, 2004, LNCS 3270, Springer, 2004.
- Mokrane Bouzeghoub ... [et al.] (eds.): Semantics of a networked world. Semantics for grid databases, first international IFIP conference, ICSNW 2004, Paris, France, June 17-19, 2004, LNCS 3226, Springer-Verlag, 2004.