On the Effective Manipulation of Digital Objects: A Prototype-Based Instantiation Approach

Abstract. This paper elaborates on the design and development of an effective digital object manipulation mechanism that facilitates the gen-eration of configurable Digital Library application logic, as expressed by collection manager, cataloguing and browsing modules. Our work aims to resolve the issue that digital objects typing information can be cur-rently utilized only by humans as a guide and not by programs as a digital object type conformance mechanism. Drawing on the notions of the Object Oriented Model, we propose a “type checking ” mechanism that automates the conformance of digital objects to their type defini-tions, named digital object prototypes. We pinpoint the practical benefits gained by our approach in the development of the University of Athens Digital Library, in terms of code reuse and configuration capabilities.

Investigating the effectiveness of client-side search/browse without a network connection

Search and browse, incorporating elements of information retrieval and database operations, are core services in most digital repository toolkits. These are often implemented using a server-side index, such as that produced by Apache SOLR. However, sometimes a small collection needs to be static and portable, or stored client-side. It is proposed that, in these instances, browser-based search and browse is possible, using standard facilities within the browser. This was implemented and evaluated for varying behaviours and collection sizes. The results show that it was possible to achieve fast performance for typical queries on small- to medium-sized collections

On the effective manipulation of digital objects: A prototype-based instantiation approach

This paper elaborates on the design arid development, of an effective digital object manipulation mechanism that facilitates the generation of configurable Digital Library application logic, as expressed by collection manager, cataloguing and browsing modules. Our work aims to resolve the issue that digital objects typing information can be currently utilized only by humans as a guide and riot by programs as a digital object type conforniance mechanism. Drawing on the notions of the Object Oriented Model, we propose a "type checking" mechanism that automates the conformance of digital objects to their type definitions, named digital object prototypes. We pinpoint the practical benefits gained by our approach in the development of the University of Athens Digital Library, in terms of code reuse and configuration capabilities. © Springer-Verlag Berlin Heidelberg 2005

Digital object prototypes: An effective realization of digital object types

Digital Object Prototypes (DOPs) provide the DL designer with the ability to model diverse types of digital objects in a uniform manner while offering digital object type conformance; objects conform to the designer's type definitions automatically. In this paper, we outline how DOPs effectively capture and express digital object typing information and finally assist in the development of unified web-based DL services such as adaptive cataloguing, batch digital object ingestion and automatic digital content conversions. In contrast, conventional DL services require custom implementations for each different type of material. © Springer-Verlag Berlin Heidelberg 2006

Introducing Pergamos: A fedora-based DL system utilizing digital object prototypes

This demonstration provides a "hands on" experience to the "internals" of Pergamos, the University of Athens DL System. Pergamos provides uniform high level DL services, such as collection management, web based cataloguing, browsing, batch ingestion and automatic content conversions that adapt to the underlying digital object type-specific specialities through the use of Digital Object Prototypes (DOPs). The demonstration points out the ability of DOPs to effectively model the heterogeneous and complex material of Pergamos. Special focus is given on the inexpensiveness of adding new collections and digital object types, highlighting how DOPs eliminate the need for custom implementation. © Springer-Verlag Berlin Heidelberg 2006