Judith S. Rodríguez

Educational metadata and brokerage for learning resources

The learning technology standardization process is one of the key research activities in computer-based education. Institutions like the IEEE, the US Department of Defense and the European Commission have set up committees to deliver recommendations and proposals in this area. The objective is to allow the reuse of learning resources and to offer interoperability among heterogeneous e-learning systems. The first part of this paper is devoted to the presentation of an up-to-date survey on one of the most prolific fields of the learning technology standardization: educational metadata. The second part shows how these data models are applied by actual software systems to facilitate the location of learning resources. Educational brokerage is a promising field that lets learners find those computer-based training resources that best fit their needs. We identify the main actors involved, their roles, and open issues and trends.

Observing Standards for Web-Based Learning from the Web

Learning technology standardization is a lively process that will last for years until a clear and precise set of recommendations are identified. So far, there is only one official standard and some final specifications in different ar- eas. Most documents are working drafts that are still in their development proc- ess before being approved and, most important, accepted by the global e- learning community. Currently, many institutions collaborate to produce new updates almost every week. In this situation it is really hard to get familiar with the learning technology standardization process and, even worse, to keep up- dated. The Workshop for Learning Technologies, within the European Com- mittee for Standardization (CEN/ISSS WS-LT), produced the Learning Tech- nology Standards Observatory, a web portal where those interested in this proc- ess can get familiar with it, learn the main differences between related specifi- cations, follow what is going on, what is planned for the near future and fur- thermore participate in the process itself. This paper presents the main function- alities and content areas within this site and how users can benefit from its use.

Architecting CORBA-based frameworks to support distributed and interoperable training systems in large enterprises

Enterprise software systems are mainly distributed. Distribution promises better efficiency, scalability, and availability, specifically of large-scale systems. This is also true for the computer-based training systems used by training departments. This paper addresses interoperability and reusability issues that appear as a consequence of the heterogeneous nature of the resources used for training. We propose a CORBA-based framework to develop distributed object computing systems to support enterprise training. This proposal is based on ongoing work by institutions like the US Department of Defense and the aviation industry in the learning technology standardization area. Our framework also identifies open software interfaces among distributed components and a systematic methodology to develop new systems from them. Therefore, architects are provided with a software product line to develop standards-driven interoperable distributed training systems.

An Online Environment Supporting High Quality Education in Computational Science

Education in Computational Science is a demanding task, especially when online support is required. From the learners point of view, one of the most challenging issues is to get used to the supporting tools, especially with the computing devices employed (e.g. DSPs). For this, students need to understand concepts from the Computer Architecture area. This paper presents a WWW-based virtual laboratory that provides learners with a suitable environment where Computer Architecture concepts, needed to face Computational Science education, can be acquired. Our contribution can be described as an open distributed platform to provide practical training. Services offered support the seamless integration of simulators written in Java, and include features like student tracking, collaborative tools, messaging, task and project management, or virtual file repositories. A CORBA-based distributed architecture to access real computer systems, available in labs at University facilities, is also described.

Standardisation in telE-learning: A critical analysis

Over the last few years there has been a proliferation of many heterogeneous tele-learning systems. This outcome has been a consequence of the increased use of the internet and its technological capabilities as the supporting environment for this kind of system. This heterogeneity means that, in most cases, different systems cannot interoperate, and learning resources developed for one system cannot be reused in another. To overcome these disadvantages it is necessary to look at a standardisation process. This paper presents an upto-date critical survey of the work in the main institutions involved in this process, together with the presentation and analysis of the most outstanding outcomes.

A web services broker for e-learning

Brokerage enriches the traditional searching services to include resource acquisition, distribution and billing and perfectly adapts to a scenario like e-learning where multiple, independent content providers and service providers exist. Brokerage offers a suitable framework where customers, mainly learners, can get in touch with providers. On the one hand, customers can locate, select and access the resources and services offered by providers in an efficient way. On the other hand, providers can benefit from services as marketing, customizable publicizing, or even accounting and billing. This paper proposes a brokerage architecture for Web-based E-learning services. It facilitates the integration of individual software components providing specific services to compose a complete E-learning environment.

A distributed object computing approach to e-learning

We present a preliminary proposal towards a CORBA domain facility for e-learning. This proposal may be seen as an initial contribution to the definition of an object-oriented distributed architecture for this domain. E-learning is one of the killer applications in the new information society. Many e-learning systems have been developed, targeted to specific learning scenarios and execution environments. In most cases, properties like interoperability or scalability were not taken into consideration when developing these applications, and as a consequence, systems with similar functionalities were developed again and again. To address this problem, two actions are possible: the standardization of this domain, and the definition of reference models and architectures that facilitate software reuse and the development of scalable and interoperable systems. These two actions complement each other, and our proposal is based on available results from the e-learning standardization process.

Modeling Metadata-Enabled Information Retrieval

We introduce a proposal to theoretically characterize Information Retrieval (IR) supporting metadata. The proposed model has its foundation in a classical approach to IR, namely vector models. These models are simple and implementations are fast, their term-weighting approach improve retrieval performance, allow partial matching, and support document ranking. The proposed characterization includes document and query representations, support for typical IR-related activities like stemming, stoplist application or dictionary transformations, and a framework for similarity calculation and document ranking. The classical vector model is integrated as a particular case in the new proposal.

Moving the business logic tier to the client: cost-effective distributed computing for the WWW

The Internet and the WWW have encouraged the adoption of a three‐tiered architectural style as the general framework for distributed computing. The thin client concept associated with this model is the most suitable for the WWW, because it can be easily mapped to the browser concept. Additionally, the separation of business logic (middle tier) and back‐end services enable further flexibility for the design of this kind of service. Nevertheless, the advent of platform‐independent software models like Java and the availability of common off‐the‐shelf services, like FTP or HTTP, offer new opportunities to more classical distributed computing models. In this paper we revisit the two‐tiered model for Internet environments, and show that the fat client (user interface plus business logic) may still be valid, at least in some environments. We propose two solutions to provide full FTP access from a Java applet. Copyright

A focal access point to follow the standardization of learning technologies

The Workshop for Learning Technologies, within the European Committee for Standardization (CEN/ISSS WS-LT), produced the Learning Technology Standards Observatory, a Web portal where those interested in the LT standardization process can get familiar with it, learn the main differences between related specifications, follow what is going on, what is planned for the near future and furthermore participate in the process itself. This paper presents the main functionalities and content areas within this site and how users can benefit from its use.