Harald Kosch

A data generator for cloud-scale benchmarking

In many fields of research and business data sizes are breaking the petabyte barrier. This imposes new problems and research possibilities for the database community. Usually, data of this size is stored in large clusters or clouds. Although clouds have become very popular in recent years, there is only little work on benchmarking cloud applications. In this paper we present a data generator for cloud sized applications. Its architecture makes the data generator easy to extend and to configure. A key feature is the high degree of parallelism that allows linear scaling for arbitrary numbers of nodes. We show how distributions, relationships and dependencies in data can be computed in parallel with linear speed up.

Towards an easy to use authoring tool for interactive non-linear video

With growing bandwidths in the Internet and seemingly unlimited storage capacities on web servers, media became more and more important in the daily use of the World Wide Web. While about ten years ago only text and images with small file sizes (and as a result small resolutions) could be used, it is possible to watch high quality multimedia presentations nowadays. But those rarely exist because of tedious to learn authoring tools. A specialization to one main medium, in our case video, allows creating efficient authoring tools using well known paradigms. This work introduces an authoring tool called SIVA Producer. An iterative process for improving the usability of the authoring tool is described. Furthermore, a distinction of the terms “interactive video”, “annotated video”, “non-linear video” and “hypervideo” is given.

SIVA suite: authoring system and player for interactive non-linear videos

In this paper, an intuitive authoring system and player for interactive non-linear video called SIVA Suite is presented for demonstration. Such videos are enriched by additional content. Possible forms of additional content are plaintext, richtext, images and videos. Interactivity is implemented based upon selection buttons which allow the user to follow different plotlines. Additional forms of interactivity are realized as clickable objects in the video and a table of contents for the video. The software provides a tool for manually cutting videos and an automated shot detection. The non-linear flow of the video can be designed using a scene graph with fork nodes. Editors for text and images support the user in adding information to the video. A finished video project is exported to an XML file with a specific schema and Flash video (flv) files. The player processes the XML file, plays the interactive video and shows additional contents. It can be customized to the requirements of the presentation of the video and the corporate design of the homepage the video is embedded in.

Extracting User Interests from Search Query Logs: A Clustering Approach

This paper proposes to enhance search query log analysis by taking into account the semantic properties of query terms. We first describe a method for extracting a global semantic representation of a search query log and then show how we can use it to semantically extract the user interests. The global representation is composed of a taxonomy that organizes query terms based on generalization/specialization (“is a”) semantic relations and of a function to measure the semantic distance between terms. We then define a query terms clustering algorithm that is applied to the log representation to extract user interests. The evaluation has been done on large real-life logs of a popular search engine.

Efficient and Flexible XML-Based Data-Exchange in Microcontroller-Based Sensor Actor Networks

One of the critical challenges in embedded sensor actor networks is the communication between the diversity of widespread nodes. XML-based message formats are already widely adopted in other IT domains such as the Web and would be perfectly suited for data exchange in heterogeneous environments. Despite all its strengths, the common markup language cannot be adopted on small embedded devices with limited resources due to its verbosity and associated processing overhead. The paper describes an innovative source code generation technique by means of W3Cs Efficient XML Interchange (EXI) format that enables the efficient usage of XML-based messages on small devices with limited resources. The outcome is an EXI Processor that allows an end-to-end XML-based communication between systems ranging from powerful workstations to microcontroller-based systems. Particularly, the paper emphasizes the flexibility with regard to alter an exchange format and its minimal adaption efforts due to the generated EXI Processor. An example application proves the applicability of the proposed approach and demonstrates a real life show-case for XML-based Web service communication on microcontroller-based devices.

AIR: Architecture for interoperable retrieval on distributed and heterogeneous multimedia repositories

Nowadays multimedia data is produced and consumed at an ever increasing rate. Similarly to this trend, diverse storage approaches for multimedia data have been introduced. These observations lead to the fact that distributed and heterogeneous multimedia repositories exist whereas an unified and easy access to the stored multimedia data is not given. This paper presents an architecture, named AIR, that offers the aformentioned retrieval possibilites. To ensure interoperability, AIR makes use of recently issued standards, namely the MPEG Query Format (MPQF) (multimedia query language) and the JPSearch transformation rules (metadata interoperability).

Efficient XML Interchange for rich internet applications

The tremendous acceptance of web applications, or more specifically, rich media applications are about to be extended to embedded devices such as mobile phones, digital picture frames or TV sets. The Extensible Markup Language (XML) is one important pillar when we deal with such internet applications. XML is known as the interchange language of the web. Besides its outstanding features, in the domain of embedded devices, XML is difficult to handle due to the processing overhead and the verbosity associated with its use. This paper evaluates the efficient access of rich internet applications especially in the domain of resource limited embedded devices such as digital picture frames. For this purpose, typical XML source information models for rich internet applications, such as Silverlight and SVG, are evaluated. In this context, the new Efficient XML Interchange (EXI) format is applied and studied. Finally a generic adaption of the EXI format is developed to even increase the efficiency. The paper concludes with the proposal for further studies on an integration of EXI-based typed interfaces to reduce the processing complexity for rich media applications on embedded devices.

Balloon Fusion: SPARQL rewriting based on unified co-reference information

While Linked Open Data showed enormous increase in volume, yet there is no single point of access for querying the over 200 SPARQL repositories. In this paper we present Balloon Fusion, a SPARQL 1.1 rewriting and query federation service build on crawling and consolidating co-reference relationships in over 100 reachable Linked Data SPARQL Endpoints. The results of this process are 17.6M co-reference statements that have been clustered to 8.4M distinct semantic entities and are now accessible as download for further analysis. The proposed SPARQL rewriting performs a substitution of all URI occurrences with their synonyms combined with an automatic endpoint selection based on URI origin for a comprehensive query federation. While we show the technical feasibility, we also critically reflect the current status of the Linked Open Data cloud: although it is huge in size, access via SPARQL Endpoints is complicated in most cases due to missing quality of service.

A mobile player for interactive non-linear video

With rapid improvements in available bandwidth and processing power of smart phones, the presentation of interactive non-linear video became possible. Web players for these form of video already exist, they usually have a video area and one or more annotation areas. Most of them can not be used for mobile phones because of their space consuming representation. This work presents a player to display interactive nonlinear videos on Android smart phones. The small display size and the possibility to switch between portrait and landscape mode have been taken into account. The player also provides functions to manage a library of downloaded interactive videos for off line use as well as bookmarks.

Standardized interoperable image retrieval

Digital still images are generated, distributed and stored worldwide at an ever increasing rate. Yet, the large number of available metadata description formats prevents consistent and efficient access to image repositories. Standardized solutions for unifying the access and the retrieval of image repositories are therefore strongly needed. The ISO/IEC SC29 WG1 (more commonly known as JPEG) established the JPSearch project, which aims to standardize interfaces of an abstract image retrieval framework. In this context, the paper introduces our contribution consisting of a reference metadata model, which in combination with the JPEG query format improves interoperable image retrieval for users. Second, a transformation rule declaration language for query reformulation is presented, which contributes to interoperability at the repository side.