Abstract. For the past two years the Moving Pictures Expert Group (MPEG), a working group of ISO/IEC, have been developing MPEG-7 [1], the "Multimedia Content Description Interface", a standard for describing multimedia content. The goal of this standard is to develop a rich set of standardized tools to enable both humans and machines to generate and understand audiovisual descriptions which can be used to enable fast efficient retrieval from digital archives (pull applications) as well as filtering of streamed audiovisual broadcasts on the Internet (push applications). MPEG-7 is intended to describe audiovisual information regardless of storage, coding, display, transmission, medium, or technology. It will address a wide variety of media types including: still pictures, graphics, 3D models, audio, speech, video, and combinations of these (e.g., multimedia presentations). MPEG-7 is due for completion in October 2001. At this stage MPEG-7 definitions (description schemes and descriptors) are expressed solely in XML Schema [2-4]. XML Schema has been ideal for expressing the syntax, structural, cardinality and datatyping constraints required by MPEG-7. However it has become increasingly clear that in order to make MPEG-7 accessible, re-usable and interoperable with other domains then the semantics of the MPEG-7 metadata terms also need to be expressed in an ontology using a machine-understandable language. This paper describes the trials and tribulations of building such an ontology represented in RDF Schema [5] and demonstrates how this ontology can be exploited and reused by other communities on the semantic web (such as TV-Anytime [6], MPEG-21 [7], NewsML [8], museum, educational and geospatial domains) to enable the inclusion and exchange of multimedia content through a common understanding of the associated MPEG-7 multimedia content descriptions. 1.

This paper describes the latest version of the ABC metadata model. This model has been developed within the Harmony international digital library project to provide a common conceptual model to facilitate interoperability between metadata vocabularies from different domains. This updated ABC model is the result of collaboration with the CIMI consortium whereby earlier versions of the ABC model were applied to metadata descriptions of complex objects provided by CIMI museums and libraries. The result is a metadata model with more logically grounded time and entity semantics. Based on this model we have been able to build a metadata repository of RDF descriptions and a search interface which is capable of more sophisticated queries than less-expressive, object-centric metadata models will allow.

The success of collaborative hypermedia systems in business, engineering, or humanities heavily depends on the discursive nature of knowledge creation. Informing systems that assist crossdisciplinary communities of practice in these fields should therefore be able to capture, to visualize, and to support the ongoing scientific discourse to keep participants informed and committed to the knowledge creation process. We present a solution for this issue, using the MECCA discourse support system for a movie research community as an example. MECCA integrates research processes with teaching processes in the humanities. Our study demonstrates that knowledge creation discourses involve a lot of re-“writing ” (transcription) of discourse artifacts within or across media. We introduce an underlying formal technique to support flexible and adaptable transcription on hypermedia artifacts in the community. Our approach includes a linkage of knowledge to action which aims at seamless de-contextualization from action and recontextualization into action. Keywords: Hypermedia, discourse support, humanities, MPEG-7, CSCL.

Web Services are designed for loosely coupled systems, which means that in many cases it is not possible to synchronously upgrade all peers of a Web Service scenario.

INTRODUCTION Digital interchange is a growing activity that is beginning to be accompanied by attention to preserving content for periods that exceed practical technology lifetimes and sometimes human lifetimes. What might someone a century from now want of information created today? For some applications, people will want evidence that the information they depend on is authentic. [Bearman 2] [Gladney 2] Consider what some user might want of a century-old digital object, and of any object it depends on: (1) A copy of the bit-string representing the object should have survived and be accessible. (2) The content should be comprehensible for human reading or correctly executable if it is a procedure. (3) Associated metadata should identify the purpose, historical context, and limitations of the content. (4) Consumers should be enabled to determine whether content received is trustworthy. I.e., their should be evidence that the object is what it purports to be and that it has not been alt

This article is part of a Trustworthy 100-Year Digital Objects series . The titles and themes of the series members will be: #1 Executive Summary of a Digital Preservation Proposal puts into perspective, with a minimum of technical detail, the ideas suggesting a complete technical solution for digital preservation---everything that computers can do and no more . #2 Durable Encoding For When It's Too Late to Ask treats a single question: how can data files and programs be encoded so that their potential future users can exploit them as their authors intend? #3 Evidence Even After Every Witness is Dead treats two questions: how should information be packaged to be maximally reliable in the distant future, and what infrastructure does such packaging depend on? #4 Syntax and Semantics---Tension between Facts and Valueswill treat the boundary between what can be specified precisely and automated and what must forever remain issues of human values, opinions, and imperfectly communicated intentions. This philosophic distinction is critical to issues of trust and of authenticity of preserved information. #5 What's Authentic? Essential and Accidental in Documentswill treat the limits of communicating authors' semantic intent and how deliberate redundancy can help. These semantic issues are critical to understanding the role of ontologies. #6 How Might Evolving Economics Affect Digital Archive Designwill suggest the effect of cost and quantity trends on digital repository architecture and on the roles and methods of archiving institutions. #7 End User Interfaceswill describe the design of programs suggested by 5.6 below. #8 Preservation Requirements and Architecture is an evolving top-down analysis of digital preservation requirements, prior work, and the design of our proposed s...

2. State of the Art on Multimedia data and metadata standards.................................................7 2.1 Multimedia data standards overview................................................................................7 2.1.1 Video standards..................................................................................................................7

Reading prerequisites: Because KO is a broader and more abstract context to TMs, before reading on you should have acquainted yourself with the more technical chapters on TMs in this book, i.e. with the core concepts and some examples. Suggested reading path for practitioners: Sections "Introduction", "KO, Knowledge Structures, and TMs", "Some Definitions: What Is and Does KO? To What End KO?", the example in "Key Ingredients of KO Theory, and an Introductory Example", the in-text summary in "Overview: Problems and Principles", "KO in Practice", and from "KO as a Use Case for TMs " on completely to the end. As the section "What is KO"? discusses