Heiko Thimm

A Mail-Based Teleservice Architecture for Archiving and Retrieving Dynamically Composable Multimedia Documents

In this paper, a teleservice for archiving and retrieving multimedia documents using public networks is described. This teleservice encourages a broad range of commercially applicable multimedia archiving applications suitable for an asynchronous access mechanism. It is based on an integrated architecture comprising stand alone archive clients and a multimedia archive server which is realized using a database management system. Archive clients access the archive server via an extended X.400 Multimedia Mail Teleservice. This teleservice reflects the specific requirements of dealing with multimedia documents in a networked environment by supporting a global reference mechanism. The archive server can dynamically compose new versions from an original archived multimedia document including extractions of subsequences of continuous data streams, coding and quality transformations. Thus, users can retrieve multimedia documents that explicitly reflect his individual workstation environment,information needs, and preferences. Since this feature allows to determine in advance the data volume to be retrieved and transmitted, users have more control over their service charge. The concept, architecture, and functionality of the teleservice as well as a sample instantiation of the proposed architecture showing an application called multimedia calendar of events are described. A comprehensive discussion of this prototypical implementation provides our experiences.

/spl delta/-sets for optimized reactive adaptive playout management in distributed multimedia database systems

A novel database system service called a playout management service, which performs multimedia presentations was proposed by the authors recently [1st Int. Workshop on Multimedia Database Mgmt. Systems, pp. 38-47, 1995]. In distributed multimedia database systems without end-to-end guarantees, such a playout management service faces the potential problem that system performance can become insufficient when realizing a stored presentation. This problem can be overcome by making the playout management service reactive, such that it balances the amount of data to be fetched from a remote multimedia database with the system performance that is available. For the users, this means that a running presentation is adapted by the playout management service. In this paper, we propose the concept of a /spl delta/-set to adapt the execution of arbitrary multimedia presentations in an optimized way. We present a heuristic scheme to identify the most adequate /spl delta/-set with respect to (1) the actual system state, (2) the user preferences, and (3) the specific properties of multimedia presentations.

A Multimedia Enhanced CSCW Teleservice for Wide Area Cooperative Authoring of Multimedia Documents

This paper presents the concept and general architecture of a multimedia enhanced CSCW teleservice that controls and monitors cooperative multiauthoring processes for possibly multimedia documents. Involved authors can be worldwide geographically dispersed. The instantiation of such a process is performed by submitting a workflow specification including multimedia directives which informally describe corresponding authoring activities. Document components completed in preceding authoring activities can be specified as activity input. The document data are fully incorporated within the workflow artifacts. The central component is a multimedia archive that provides integrated workflowand document management functionality. A multimedia mail teleservice designed for public networks is used as communication means. Using the proposed CSCW teleservice, authoring processes can be completed in a smooth, reliable, and timely manner. Authors are relieved from tasks that bear a high potential for workflow violations and delay.

Managing adaptive presentation executions in distributed multimedia database systems

The paper describes recent progress in research on database system support for executing multimedia presentations. It proposes the general concept of reactive playout management to adjust multimedia presentations. This adjustment can be required due to performance fluctuations as in the absence of end-to-end quality of service guarantees, cost constraints specified by the user and other reasons. A concrete concept to realize performance-based reactive playout management in distributed multimedia database systems is proposed. This covers the identification of respective components in distributed database system architectures along with corresponding algorithms.

Playout management-an integrated service of a multimedia database management system

Playout management subsumes lower and higher level system tasks necessary to execute stored multimedia presentations. For multimedia database management systems, we propose the integration of a respective playout management service. On one hand, this provides optimal database management support for multimedia applications. On the other, this makes the handling of multimedia data within a multimedia database management system more efficient since the storage, retrieval, buffering, and playout management is performed by one consistent system. As an example, we introduce the integrated playout management service of the AMOS system, a distributed object-oriented multimedia database management system. An extension toward reactive adaptive playout management making the multimedia database management system able to overcome insufficient system performance while realizing multimedia presentations is also briefly discussed.

Optimization of adaptive data-flows for competing multimedia presentational database sessions

Multimedia database systems must accommodate the capability to adapt the resource demand of executing presentations. This concerns adaptations across components of presentations as well as across concurrent sessions adhering to the individual needs of content providers and viewers. This paper describes the general concept of Reactive Playout Management (RPM) which provides an application-independent service for adaptive multimedia presentations. Furthermore, it proposes the PYLOT scheme (PlaYout Load OpTimization scheme) to enable RPM in best-effort architectures. In particular the global resource allocation routine of PYLOT is elaborated which manipulates the load proportions such that minimal total adjustment costs and maximal total adjustment profit are achieved, respectively. This linear programming based optimization is demonstrated by experimental results.

A DBMS-Based multimedia archiving teleservice incorporating mail

In this paper, a teleservice for archiving and retrieving multimedia documents using public networks is described. This teleservice encourages a broad range of multimedia archiving applications. The described implementation is based on standardized multimedia mail and suitable for an asynchronous access mechanism. The originality of this work is the integration of multimedia mail with simple standalone archive clients for heterogeneous platforms and an archive server which is based on an object-oriented DBMS. The modeling of the server is described indepth showing the contributions of object-oriented database technology for the realization of generic electronic archives that deal with structured multimedia documents. Helpful hints and important design suggestions for the implementation of advanced archive functionality are provided. Furthermore, functionality for efficient access on the client side is outlined. A sample application showing a Multimedia Calendar of Events is sketched as well.

An information support service for moderators of SME company networks

Purpose – This paper aims to investigate the management process in company networks. A new information support service can assist network managers in the complex task of orchestrating members of the network to so‐called network actor sets (NAS) that deliver the “best fit” for incoming inquiries.Design/methodology/approach – A corresponding conceptual framework and system approach is developed. The proposed system employs a pragmatic two‐phase multi‐criteria scoring scheme for orchestrating NAS under consideration of the specific needs of inquiries and, too, the company network as a whole.Findings – The research indicates that the orchestration of NAS may be effectively performed by a corresponding information technology (IT) support service. Through the service orchestration decisions may become less influenced by human factors. The service will also lead to better transparency, traceability, and analytical possibilities regarding the inquiry management process. Networks with a high number of members and ...

Cloud-Based Collaborative Decision Making: Design Considerations and Architecture of the GRUPO-MOD System

The complexity of many decision problems of todays globalized world requires new innovative solutions that are built upon proven decision support technology and also recent advancements in the area of information and communication technology ICT such as Cloud Computing and Mobile Communication. A combination of the cost-effective Cloud Computing approach with extended group decision support system technology bears several interesting unprecedented opportunities for the development of such solutions. These opportunities include ubiquitous accessibility to decision support software and, thus, the possibility to flexibly involve remote experts in group decision processes, guided access to background information, and facilitation support to direct group decision processes. The architects of such future solutions are challenged by numerous requirements that need to be considered and reflected in an integrated architectural approach. This article presents a thorough analysis of major design considerations for software solutions for collaborative decision making from a broad range of perspectives especially including the business process management perspective and the Cloud Computing perspective. The proposed architectural approach of the GRUPO-MOD system demonstrates how one can address the requirements in one integrated system architecture that supports different deployment options of Cloud Computing. A refinement of the high-level system architecture into a corresponding implementation architecture that builds on widely adopted standards such as OSGi and industry proven technology such as the Eclipse platform is also given in the article.

Playout Management in Multimedia Database Systems

The presence of multiple multimedia data streams, e.g., an audio data stream in conjunction with several video data streams within a complex advertisement show, which presentation must proceed in a mutually synchronized manner, is one of the unique features that distinguishes digital multimedia data from traditional, conventional, alphanumeric data. Sample applications in which this property of digital multimedia is especially important are electronic publishing, digital libraries, computer-based training or teaching (edutainment), advertisement, entertainment, and infotainment. Here, to form modularly structured presentations, multimedia information is “glued” together by designers (i.e., presentation authors) in a preorchestration phase. While some standards relevant for this phase such as SGML/HyTime [18] or MHEG [30] are more oriented towards multimedia/hypermedia documents, others such as PREMO [17] and ScriptX [47] emphasize more time-based multimedia presentations. The result of this phase is a predefined/preorchestrated multimedia presentation for which it is assumed that its realization is requested many times by many different (possibly simultaneous) users. Many multimedia application domains such as those mentioned before need to support a pool of such preorchestrated multimedia presentations. Support of user interactions is an important property to be provided within this context (“interactive multimedia”). It provides for users flexibility in presentation control by offering the possibility to adapt the presentation realization phase to the individual needs.