Experience with the Maxwell System

      The Maxwell System (Pontifícia Universidade Católica do Rio de Janeiro. Maxwell Project) is a product of LAMBDA - Laboratório de Automação de Museus, Bibliotecas Digitais e Arquivos (http://www. lambda.ele.puc-rio.br/). It was developed taking into consideration the 20 items mentioned previously. It integrates a digital library, a learning environment and the administrative and technical functions that support them. It is multilingual since its database is neutral and can receive items in as may languages as desired. Currently it is implemented in Portuguese, Spanish and English. The Maxwell System is compatible with the university’s administrative systems and can identify information coming from these.

      The digital library portion contains all the programs to catalog and upload the LO’s. No LO is used in the system if it is not included in the library. Authors are not allowed to upload objects into the system. The cataloging is done using more than 20 metadata; there are authors, publishers and languages tables. All metadata are stored in the system database and their generation occurrs prior to uploading the objects. The metadata related to the logical part are created when the content (the logical identification) is cataloged and the ones concerning the instance are written when the object (instance) is uploaded. There are five levels of access control and four levels for sharing control; the levels of both controls are stored in the database because they belong to the metadata set. There is control of versions and of translations.

      When a digital instance of a physical object is cataloged, metadata describe the publisher, the ISO identification, the institution where it exists, the library system where the cataloguing was generated and the corresponding call number. This situation applies for instance to electronic theses and dissertations which were presented in paper before going digital.

      The architecture of the system includes only one catalogue server but there can be as many object servers as necessary. Currently there are two object servers. The identification of the object servers are stored in the instance metadata. There is no object duplication. The use of more than one object server came from the requirement of MatMídia (Pontifícia Universidade Católica do Rio de Janeiro, Mathematics Department) a laboratory in the Math Department where learning objects devoted to teaching mathematics are developed. The MatMídia team wanted the LO’s to be stored on their server. The concept and the implementation were developed to be general and include servers in any place.

      The library has query and search/retrieve programs that allow the user to find the contents independently of the courses they are used in. There are searches by author, title and keywords, besides queries by type of content.

      Since most authors allow the use of their courseware in courses that other faculty are teaching, the experience has shown that many contents are used by different instructors in the same courses or in different courses (Cardoso & Pavani 2000). Sometimes the author uses the same content in different courses he/she is teaching. This is possible since the instances are stored in the digital library, course contents are discriminated in tables on the database by their number and the system retrieves them from the storage using programs.

      Another positive experience with the digital library supporting the system is the effective maintenance of contents and storage space this provide. Both are consequence of the uniqueness of each instance in the system.