A Grid-based Architectural Framework for Composition and Execution of Complex Learning Processes Jorge Torres Cesar Cárdenas Tecnológico de Monterrey, Mexico jtorresj@itesm.mx, ccardena@itesm.mx Juan Manuel Dodero Ignacio Aedo Universidad Carlos III de Madrid, Spain dodero@inf.uc3m.es, aedo@ia.uc3m.es Abstract Educational Modeling Languages (EML) are currently used to design and specify complex learning process that adapt the demands of a particular learning setting. LPCEL (Learning Process Composition and Execution Language) is a formal language used to specify complex learning scenarios. From a software architectural point-of-view, a service-oriented architecture (SOA) provide an important approach in order to implement dynamically learning environments from diverse, distributed and heterogeneous learning resources and services, these can be hardly synchronized and coordinated through an EML specification. Based upon SOA principles, Grid-Computing offer a powerful environment to use of resources such as processing power, disk storage, applications and data. This work presents a grid-based architectural framework that enable the dynamic and unanticipated composition of distributed learning services. 1. Introduction Educational Modeling Languages (EML) are currently used to design and specify learning processes that adapt the demands of a particular learning setting [1]. Although EML are driving significant improvements, they are merely descriptive languages that explicit a given learning design [2]. Nevertheless, an EML specification is usually decoupled from the run-time environment in which it is to be deployed and executed (e.g. IMS-LD) [2]. With the exception of learning flow descriptions, EML provides limited expressiveness to describe and guide the execution of a learning process. Additionally, if the learning process includes the execution of a number or heterogeneous learning
services, these can be hardly synchronized and coordinated through an EML specification. In order to solve these issues, the Learning Process Composition and Execution Language (LPCEL) has been defined [2]. LPCEL is used to describe the execution of a learning process and to orchestrate the services and resources that are needed to carry it out. It facilitates the integration of external applications and services with a pedagogical objective. LPCEL is not only a language but the core element of a service-oriented architecture that is intended to facilitate the access to a set of decentralized services, which users can successfully integrate, compose, and execute within a complex learning process (CLP) [3]. Sometimes, to execute a rich learning scenarios it is necessary to have a set applications (i.e. services) that require a high-capacity and high-performance (e.g. processing power, data storage, applications, memory, and network, among others) [11][12][13]. Grid-computing has been developed a way to solve this highly complex problem [6]. The objective of our work is: (1) to provide a overview of LPCEL; and (2) to define a grid-based service-oriented architecture framework for the composition and execution of learning processes that can be used as a general framework where that language can be implemented. The rest of the paper is structured as follows: section 2 describes the part of the LPCEL that can be applied to describe the learning activity execution of a CLP; section 3 outlines the concept of grid-computing, discussing as Grids are facilitated by the use of middleware technologies (i.e. SOA); in section 4 the grid-based architectural framework are presented; and finally some conclusions are provided in section 5.
Eighth IEEE International Conference on Advanced Learning Technologies
978-0-7695-3167-0/08 $25.00 © 2008 IEEE
DOI 10.1109/ICALT.2008.292
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