Quality interoperability within digital libraries: the DL.org perspective

Quality is the most dynamic aspect of DLs, and becomes even more complex with respect to interoperability. This paper formalizes the research motivations and hypotheses on quality interoperability conducted by the Quality Working Group within the EU-funded project DL.org (<a href="http://www.dlorg.eu">http://www.dlorg.eu/</a>). After providing a multi-level interoperability framework – adopted by DL.org - the authors illustrate key-research points and approaches on the way to the interoperability of DLs quality, grounding them in the DELOS Reference Model. By applying the DELOS Reference Model Quality Concept Map to their interoperability motivating scenario, the authors subsequently present the two main research outcomes of their investigation - the Quality Core Model and the Quality Interoperability Survey

Collections and Access Policies of the Digital Material of Ten National Libraries

We examine and analyze the access policies of the digital collections of ten national libraries. We classify the implemented access policies, according to their characteristics, and we show their differences. We generalize the diversified access policies, by combining the varying parameters and other relevant emerging ones. Most national libraries prefer digitizing or make digitally available, part of their material, the one that is simpler in accessing restrictions, which was simpler to implement and more appropriate to do first. As this process evolves and matures, the libraries want to make more material available, and this will force them to handle material that is more complex in terms of copyright and access. Thus, we should predict and standardize new access policy variations. We propose a generalized access policy, on which, we classify the users up to four groups that have non-increasing access abilities, as will be defined by the implemented policy. We also propose new charging and delivery parameters for use or reproduction of the non-free and copyrighted digital material

Architectures for QoS based Retrieval in Digital Libraries

Introduction Digital Libraries will have a major influence on the design of future information systems. They will form the cradle from which future complex information technologies will emerge to provide "transparent" services to a variety of users. In Digital Libraries[1], many real-world agents will participate for various economic reasons. For example, publishers of books will place their collections in a digital format to reduce production costs and increase profit margins. Many other types of economic entities will flourish for reasons of lower costs and higher revenue. With the rapid advances in computer and networking technology, thousands of heterogeneous computers can be interconnected to provide a large collection of computing and communication resources. Such a collection will be used by Digital Libraries to house various information objects such as text, audio, video and image, and provide various information access services (quali

A Performance Framework for QoS based Searching and Retrieval in Digital Libraries

In this paper, we investigate the issues of performance management and Quality of Service in large scale, autonomous and federated Digital Library systems consisting of many hundreds of servers performing the tasks of indexing, searching and retrieval of information objects. Our contributions are the following: we present a distributed performance management framework for measurement, monitoring and QoS based searching in Digital Library Systems. We designed and implemented our performance monitoring framework and measurement mechanisms over a testbed of NCSTRL based Dienst servers. We defined relevant parameters for investigating the performance of the servers. Using these parameters and the framework, we developed novel load balancing algorithms for distributed searching over a network of Index servers. In addition, we propose mechanisms for dynamic timeout adaptation for the distributed searches. We studied the performance of one of the load balancing algorithms via simulations. T..