Nick Carroll

Abstract: ePortfolios and the learning artifacts they contain must be portable and accessible for the purpose of supporting life-long learning experiences. In this paper, we identify that ePortfolios must also maintain the credibility of the learning artifacts, especially assessment artifacts that are used as evidence by the learner for demonstrating a particular competency. These assessment artifacts are vulnerable to modification or alteration during transfer between distributed ePortfolio systems. As a result, we propose the use of certified assessment artifacts to detect these vulnerabilities. We also present a distributed architecture for a virtual learning environment that incorporates the sharing of certified assessment artifacts between a learning management system, and an ePortfolio system called dotFOLIO that we are currently developing.

Citation: Nicholas L. Carroll and Rafael A. Calvo. “Certified Assessment Artifacts for ePortfolios”. To be published in, Proceedings of the International Conference on Information Technology and Applications (ICITA’05), July 2005, IEEE Computer Society.

Abstract: Database systems are an essential component in multi-tiered web applications. These applications increasingly interact with others using web services. In this paper, we describe and compare two architectures for integrating web services into web applications, and perform performance benchmarks using the Google web service. For one of the architectures we contribute a SOAP interface to the PostgreSQL Relational Database Management System, implemented as a user-defined function that allows developers to make service calls from within the database. We show that SQL can be used to easily query data provided by web services, and therefore as a way of accessing and using web services in a database-driven web application.

Citation: Nicholas L. Carroll and Rafael A. Calvo. “Integrating Web Applications and Web Services”. To be published in, Proceedings of the 5th International Conference on Web Engineering (ICWE ’05), July 2005.

Abstract: In this paper we study the integration of Web services in an object-relational database system. This allows a database to import data from live data feeds or remote heterogeneous database systems on demand. We first describe how we have added a SOAP interface to the PostgreSQL database system, implemented as a user-defined function that allows developers to make service calls from within the database. Secondly, we show that SQL can also be used to query data provided by Web services, which introduces a novel way of accessing and using Web services in a database-driven web application. Finally, we compare the performance of two architectures for consuming Web services with a benchmarking procedure using the Google Web service API.

Citation: Nicholas L. Carroll, Rafael A. Calvo. “Querying Data from Distributed Heterogeneous Database Systems through Web Services“. In Proceedings of The Tenth Australian World Wide Web Conference (AUSWEB’04), July 2004.