The NDLTD Union Catalog: Issues at a Global Scale

Conferencia realizado del 12 al 14 de setiembre en Lima, Peru del 2012 en el marco del 15º Simposio Internacional de Tesis y Disertaciones Electrónicas (ETD 2012). Evento aupiciado por la Universidad Nacional Mayor de San Marcos (UNMSM) y la Universidad Peruana de Ciencias Aplicadas (UPC).The NDLTD Union Catalog is an international collection of ETD metadata that is harvested from various institutional, regional and cross-institutional collections. The Union Catalog has grown substantially in the 10 years since its launch and now contains almost 2 million records. However, various issues have surfaced during the maintenance of the Union Catalog and its downstream service providers. For example, at this scale, the well-known best practice of the OAI-PMH to restrict the size of a response to 100 records or 1MB has a severe impact on harvesting time. This paper describes this problem and other issues that are relevant to the Union Catalog and similar projects. For each such issue, solutions are discussed. Together these present a set of guidelines not only for large union catalogues but also for the design of large digital library collections in general

A component assembly approach to digital library systems

With the advent of the Internet came the promise of global information access. In keeping with this promise, Digital Libraries (DLs) began to emerge across the world as a method of providing structured information to their users. These DLs are often created using proprietary monolithic software that is usually difficult to customise and extend. The Open Digital Library (ODL) project was created to demonstrate that DLs can be built as a network of components instead of as monolithic systems. Although the ODL approach has largely been embraced by the DL community, it is not without a few shortcomings. This paper introduces a graphical user interface and its associated framework for creating DLs from distributed components, consequently addressing a number of the limitations of ODL-like systems, as well as presenting a novel and generic approach for creating component-based systems. This system was subject to a user-based evaluation to confirm its utility and provide insights into possible extensions

Beyond Harvesting: Digital Library Components as OAI Extensions

Reusability always has been a controversial topic in Digital Library (DL) design. While componentization has gained momentum in software engineering in general, there has not yet been broad DL standardization in component interfaces. Recently, the Open Archives Initiative (OAI) has begun to address this by creating a standard protocol for accessing metadata archives. It is proposed that this protocol be extended to act as the glue that binds together various components of a typical DL. In order to test the feasibility of this approach, a set of protocol extensions was created, implemented, and integrated as components of production and research DLs. The performance of these components was analyzed from the perspective of execution speed, network traffic, and data consistency. On the whole, this work has simultaneously revealed the feasibility of such OAI extensions for component interaction, and has identified aspects of the OAI protocol that constrain such extensions

Metadata Editing by Schema

Metadata creation and editing is a reasonably well-understood task which involves creating forms, checking the input data and generating appropriate storage formats. XML has largely become the standard storage representation for metadata records and various automatic mechanisms are becoming popular for validation of these records, including XML Schema and Schematron. However, there is no standard methodology for creating data manipulation mechanisms. This work presents a set of guidelines and extensions to use the XML Schema standard for this purpose. The experiences and issues involved in building such a generalised structured data editor are discussed, to support the notion that metadata editing, and not just validation, should be description-driven

Why should African academics care about Open Access?

Prof Hussein Suleman, Associate Professor in Computer Science at the University of Cape Town was the main speaker at this Open Access Seminar. In his presentation he discussed : Arguments against Open Access, the Open Access movement - in South Africa and worldwide, the development of the UCT CS Research Document Archive and its evaluation and lastly the benefits of Open Access and why African researchers should support it.Open Access Seminar for postgraduate students and researchers, presented on Friday, 11 May 2012, in the Library auditorium, Level 3, Merensky Library II, University of Pretoria.cp201

Managing Digital Library Components

Digital library systems based on components can provide advantages such as extensibility and flexibility, but at the cost of increased complexity. High-level tools can be used to manage this complexity but only if there are appropriate machine interfaces to the pool of components. This paper discusses the facilities that were deemed absolutely necessary in order to support a wide range of independently-developed high-level functions in supporting a DL system. The common thread underlying these management interfaces suggests extensions that could be incorporated into future open interfaces for digital library components, with minimal increases in complexity, thereby maintaining the advantages of a simple component model

Utility-based high performance digital library systems

Many practical digital library systems have had to deal with scalability of data collections and/or service provision. Early attempts at enabling this scalability focused on data/services closely coupled with or tightly integrated with various high performance computing platforms. This inevitably resulted in compromises and very specific solutions. This paper presents an analysis of current high performance systems and motivates for why utility computing can subsume existing models and better meet the needs of generic scalable digital library systems

Reflections on Three Years of Archiving Research Output

While "Open Access" and "institutional repositories" have received some attention in South Africa in recent years, very few tertiary institutions and departments have made a commitment to opening up access to their research. The Department of Computer Science at UCT was one of the first departments in the country to adopt the notion of an institutional repository, albeit localized, because of a strong open access tradition within the discipline. This repository of published and working papers and reports has evolved over a period of three years to become a core part of the operations of the department. It is arguably a successful implementation of an institutional repository. As such, this paper presents an analysis of the development of the archive and its use, providing anecdotal and statistical evidence to demonstrate that such projects are indeed feasible and result in substantial visibility of research for South African institutions and their academic departments

Simple DL: A toolkit to create simple digital libraries

Digital library systems are not always successfully implemented and sustainable in low resource environments, such as in poor countries and in organisations without resources. As a result, some archives with important collections are short-lived while others never materialise. This paper presents a new toolkit for the creation of simple digital libraries, based on a long trajectory of research into architectural styles. It is hoped that this system and approach will lower the barrier for the creation of digital libraries and provide an alternative architecture for experiments and the exploration of new design ideas