Abstract:

Online assessments are an important component of any online learning system. Recently, XML standards like the IMS Question and Test Interoperability (IMS-QTI) have emerged for specifying, sharing and rendering online assessments. Like many e-Learning standards, IMS-QTI has been primarily designed for conventional browser-based applications. However, assessments are increasingly being incorporated into mobile and ubiquitous learning systems. In addition, such platforms are also being used in the context of novel pedagogical paradigms like game-based learning. For example, asking children to use mobile phones to explore a historical district incorporating location as a context is a classical example of ubiquitous learning. This means that IMS-QTI assessments have to be delivered not only on a variety of heterogeneous hardware and software platforms (different types of mobile phones), but also need to be embedded within a variety of pedagogical orientations (game-based learning). Re-implementing or modifying the IMS-QTI engine for each such unique situation from scratch can be expensive and time consuming. This is especially true for ubiquitous learning that may incorporate novel sensors, micro-controllers and actuators in addition to using various non-Internet architectures like the Zigbee or RFID protocols, for example. One software engineering approach that has emerged over the recent years to address exactly this problem is software product-line engineering. Rather than “reinventing the wheel”, product line engineering organizes development in a manner that systematically accommodate the changing needs of customers into new products by structuring and using software assets in a structured manner. A software product line is a set of software-based systems that share a common and managed set of features satisfying the specific needs of a market segment. These various products are developed from a common set of core assets in a prescribed way. The economic potentials of software product line have long been recognized in software industry. A variety of large scale projects (for example, ARES, ARESESAPS, PRAISE, Café, FAMILIES and SEI Product Line System Program etc.) have played a key role in exploring this research area and have provided significant technical knowhow and support to adopt product line approach in industrial settings. Finally, many organizations, including Philips, Hewlett-Packard, Nokia, Raytheon, and Cummins, are using this approach to achieve extraordinary gains in productivity, development time, and product quality. We have also explored the software product line approach for conventional learning objects. This paper develops a specific software product-line framework for IMS-QTI assessment engines. In specific, software product line architecture, the core underlying architectural features, product common features and product variable features are developed by using product requirement analysis, product variability analysis and product commonality analysis. This product line framework is validated by applying it to a variety of target platforms including mobile platforms using a conventional browser, mobile platform using Adobe Flash, a Zigbee-based ubiquitous wearable learning platform called Prête-à-apprendre+, a role-playing game (RPG) engine (Neverwinternights) and an RFID-based ubiquitous learning platform.

Keywords:

QTI, Software product line, ubiquitous learning, mobile learning, game-based learning.