Utilising a Multi-Agent System to Support the Deployment of Contextualised mLearning Services

Damien Meere, Ivan Ganchev, Mairtin O’Droma Telecommunications Research Centre,

University of Limerick, Limerick, Ireland. Email: damien.meere@ul.ie, ivan.ganchev@ul.ie, mairtin.odroma@ul.ie

Abstract — Enhancement of an InfoStation-based multi-agent architecture is presented. The focus of the enhancement is the system’s capability to facilitate the contextualisation of delivered service content. It adapts to varying operating environments inherent to this type of wireless access architecture, and to service delivery modes dictated by, or matched to, the personal context of the user. The educational opportunities thereby created such as support for dispersed distance learning and enriched learning environment are discussed.

Keywords- InfoStations; Multi-Agent System (MAS); Contextualisation; JADE; WURFL; mobile eLearning;

I. INTRODUCTION For the entirety of human history, educational

practices have largely maintained a certain status-quo, with educators delivering information face to face with students. However, as technological innovations have revolutionised so many aspects of life, from an individual level right up to the societal level, so too have they revolutionised modern educational practices. The field of eLearning began with the introduction of Computer-Based Training (CBT) [1] within a corporate environment, which was seen as a method of replicating the traditional educational setting. It was not long until eLearning eventually grew to incorporate a medium which would ensure its proliferation throughout the world, the Internet. As the Internet revolutionised the delivery of information, so too did it revolutionise the delivery of educational solutions. Advances in Information and Communications Technologies (ICT) have enabled eLearning, through the advent of tools such as Virtual Learning Environments (VLEs), blogs, computer aided assessments, podcasts, discussion boards and various other web-based materials, to become one of the critical core components of modern educational course delivery both within formal and informal settings. Indeed, with the continued technological advancement of ICT, eLearning has evolved from its initial utilisation as a supplementary aid to the traditional face-to-face learning paradigm, to the point where it’s now seen as viable stand-alone alternative to more traditional educational practices, particularly in the realm of distance learning. As the technologies underpinning the Internet itself have evolved and matured, so too have the strategies for applying these technologies

to meet educational goals as part of a stand-alone approach, as with distance learning, but also in more traditional educational environments. The need for a compromise between the conventional face-to-face sessions and online learning lead towards a new approach to teaching and learning, a so called hybrid or blended learning [2]. Blended learning represents a fundamental re-conceptualisation and re-organisation of the teaching and learning dynamic, starting with various specific contextual needs and contingencies (e.g., discipline, developmental level, and resources) [3].

From a student’s perspective, a blended approach can provide a great many advantages, in particular, enabling the student to foster a more personalised learning experience. Every individual has their own learning style, and the utilisation of eLearning technology in a blended environment enables the student to take a more self-paced approach to the assimilation of presented information. Blended learning enables students to step away from the static nature of traditional learning and access learning material at a time when it best suits them in their schedule. In Ireland, the shift towards the delivery of more blended learning environments has assumed even greater importance, due in no small part, to the large expansion of the Irish third-level education system over the past twenty years. Indeed, this expansion has continued for a variety of reasons. Initially the Irish government’s expansion policy on higher education indicated a goal of 72% of the 17-18 year old cohort entering higher education by the year 2020 [4]. Currently over 65% of school leavers are entering higher education [5]. This expansion has become far more rapid than expected due to high levels of unemployment in Ireland and the population as a whole turning to further education and re-training in order to become more employable. While expansion within this system may be viewed as progression and development, it also leads to a very diverse group of students in the third-level classroom. This diverse group of students requires a thorough re-evaluation of traditional teaching and learning strategies. The traditional didactic ‘jug and mug’ model of teaching and learning is no longer appropriate for many third-level classrooms, as the wide variety of mixed ability students enter the lecture hall with their own prior knowledge, experiences and learning styles. In the last number of years, the majority of the young students entering both secondary and tertiary education can be said

to be born of a digital era, or “Digital Natives” [6]. These students have grown up entirely in a connected world, where the use of technology, in various forms, is a central part of their lives. Likewise, as more and more people return to education, very often in attempt to re-skill, adapting to modern educational environments and practice can be a daunting prospect. The utilisation of eLearning in a blended learning environment is well suited to meeting the varying needs of such a diverse cohort, aiming at replacing old-fashioned time/place/content predetermined learning with a just-in-time/at-work-place/customised/on-demand process of learning [7]. However, while studies on the use of blended learning and online learning advocate technology adoption, they have also sought to recognise a number of possible pitfalls. For example, in order for the students to fully engage with the learning experience, it is vital that the focus be kept on the material being delivered, rather than the attention being drawn on the novelty of the technological medium used to convey the learning material. The technology must, in essence, act as a transparent medium through which the educational materials may be delivered. Key to an enhanced student experience is a tool that is capable of meeting both the students’ and the lecturers’ needs and one that is reliable and easy to use [3]. This calls for the utilisation of technology which can be seamlessly integrated in the students’ lives and the lessons. A possible solution, it seems, is already in the pockets of many students.

Mobile devices exhibit major potential for integration in the spheres of learning, enhancing campus-wide communication and the social inclusion/cohesion of society as a whole. As mobile technologies become the dominant mode of access to the Internet [8], what has commonly been known as eLearning, is enhanced by the new communicative potential that is mLearning. The utilisation of mobile technologies can enable higher education to extend its reach, no longer constrained by location or time, but offering true ‘anywhere-anytime-anyhow’ learning [9]. This utilisation of mobile technologies represents a huge resource that, for the most part has been left untapped as regards the delivery of learning content within educational institutions. Taking advantage of this continuing pervasiveness of modern multimedia capable technologies, mLearning represents the next step in the evolution of eLearning. Mobile technologies have the capability to revolutionise learning and provide discontinuous rather than incremental learning opportunities in libraries and campuses worldwide. The system presented in this paper seeks to harness the mobile phones carried by most students today, and facilitate a truly pervasive learning experience.

The rest of this paper is organised as follows. Section II describes the designed InfoStation-based multi-agent system and details the main components involved in facilitating the user access to services. Section III details the mechanisms incorporated into the system which facilitate the contextualisation of services, highlighting the use of both user- and service profiles. Section IV presents a detailed view of the interactions which take place

between the various system components in effectively delivery of services to users. Finally, section V concludes the paper.

II. INFOSTATION-BASED MULTI-AGENT SYSTEM ARCHITECTURE

The InfoStation-based multi-agent system detailed in this paper provides access to mLearning services, for users equipped with mobile devices, via a set of intelligent wireless access points, called Information Stations (InfoStations), deployed in key locations across a university campus [10-12]. The InfoStation paradigm was originally proposed to provide “many-time, many-where” [13] wireless data services. As opposed to facilitating ubiquitous coverage, within geographically intermittent pockets, InfoStations would offer high bit rate connectivity to broadband data and network services [14]. Our system seeks to enable registered users to access a range of eLearning services through a distributed network of InfoStations, situated at different locations (e.g. library, lecture theatres, laboratories etc). As discussed previously in [10, 15, 16], this architecture involves various entities operating within a 3-tier structure as depicted in Figure 1: user mobile devices, InfoStations, and an InfoStation Centre.

Figure 1: The 3-tier InfoStation-based network architecture.

The presented architecture harnesses the communicative potential of modern mobile devices in order to present learners with a more pervasive learning experience which can be dynamically altered and tailored to suit them. Whilst within range of an InfoStation, clients may gain access to various contextualised and personalised mLearning services and resources distributed throughout the system architecture. Due to the inherent mobility support of the system, a means of facilitating sufficient flexibility and adaptability – in overcoming issues related to the delivery of services within heterogeneous wireless deployment environments – was required. For this reason, an agent-oriented approach was adopted, which offered many benefits towards the implementation of this InfoStation-based system. Due to the target audience that this system is designed to cater for (mobile users), as well as the spatially discontinuous nature of the connectivity to the InfoStations, agents operate not just onboard the InfoStations, but also within the users mobile devices [17, 18]. These latter agents, acting as “Personal Assistants Agents” (PAA), function

autonomously in order to satisfy any user service requests they may encounter, while in or out of contact with other agents (installed on the InfoStations and/or InfoStation Centre). This agent autonomy facilitates the most efficient utilisation of the InfoStation’s often intermittent coverage. The PAA may initiate a service request, whilst within range of an InfoStation, and then pass out of the coverage area. The PAA must continue to function autonomously, adopting the functionality facilitated by the service until the user has completed the task. Once the mobile device enters within range of another InfoStation, the user profile and service information can be updated and synchronised to reflect any work completed by the user whilst outside of the system coverage area. The synchronisation of information is of paramount importance to the effectiveness of the system, as the adaptation and customisation of services depend greatly on an InfoStation having access to the most up-to-date information. Following this approach, intelligent agents operate throughout each tier of the system. Indeed the InfoStations and InfoStation Centre themselves take on the appearance of multi-agent systems (MAS). As well as the benefits of deploying agents within the client devices, the deployment of this infrastructure as a MAS also facilitates the dispersion of management functionality, whereby as additional services are required, new agents can be commissioned within the MAS to handle this functionality, without interfering with the operations of existing agents. [10, 19] describe the implementation of MAS, facilitated through the utilisation of the Java Agent DEvelopment (JADE) framework [20, 21] developed by the Telecom Italia Lab (TILAB). This software framework simplifies MAS implementation through the provision of a predefined set of services and management tools in addition to the runtime library and agent programming library.

The JADE architecture itself is completely modular. By utilising specific modules (or add-ons), JADE can be

configured to adapt to the requirements of a number of different deployment environments. This alteration of the platform is especially important within mobile environments, where the availability of resources such as processing power, memory and connectivity can have a much greater bearing on the effectiveness of JADE execution. Once of the main add-ons associated with JADE is the Lightweight Extensible Agent Platform (LEAP) module [22-24], which replaces various parts of the JADE kernel providing a modified light-weight run-time environment, enabling Foundation for Intelligent Physical Agents (FIPA)-compliant agents to execute on a wide range of Java-enabled mobile devices. For deployment of JADE-LEAP runtime environments on mobile devices with limited resources, the environment (container) can be split into two separate sections: (i) a FrontEnd which runs within the mobile device itself, and (ii) the BackEnd which runs within a fixed network entity (a mediator), as illustrated in Figure 2. This mediator is charged with instantiating and maintaining the BackEnds. Within this system, the InfoStations deployed throughout the campus take on this mediator role.

Within the InfoStation and InfoStation Centre, a set of interoperating agents, each of which fulfils various essential roles necessary for system management,

Figure 3: The InfoStation-based multi-agent environment incorporating data persistence mechanisms.

Figure 2: The JADE-LEAP split container execution.

communicate by passing ACL messages (FIPA’s [25] Agent Communication Language [26]). These various agents take responsibility for selecting (optimal mode) and establishing a client-server cross-platform connection, the conveyance of context information and the delivery of adapted and personalised service content, etc. Figure 3 illustrates the main components within this system, including the main agents involved in the service delivery, and the data persistence mechanisms incorporated into the system. The Connection Advisor Agent (CAAgent) performs the role of identifying the context of the user making the request for services from the InfoStation. The main task of this agent is to facilitate the user with a list of services directly applicable to them. When the user selects a particular service, they wish to access, the CAAgent is then tasked with supplying the location of the relevant service content to the user’s PAA, installed on the user’s mobile device, so as to enable the PAA to access the relevant service content. The list of applicable services is harnessed from the service database. Within this system implementation, the two main eLearning services offered from the InfoStation relate to the delivery of contextualised lecture content and testing materials. With this in mind, two agents are tasked with delivering these services to requesting users – the WALL Next Generation agent (WNGAgent) and the mTest delivery agent (mTDAgent). The primary task assigned to the WNGAgent is to facilitate the delivery of the requested service content to the user’s PAA. This process involves discerning the capabilities of the requesting device, in particular the file-types and mark-up supported, and then adapting the requested content to suit the operating environment onboard the requesting device. This process of contextualising the requested content is dealt with in further detail in the next section. The mTDAgent is charged with the delivery of mTests to requesting users. The mTest service [27] provides a means to evaluate the students acquired knowledge and provides valuable feedback, making the students aware of their progress in the assimilation of the presented course content, and highlighting the knowledge or skills they lack or may need to strengthen. This is achieved through the delivery of various forms of test content to the PAA [27].

III. CONTEXTUALISATION In the current market, the diversity in capabilities of

modern mobile devices and supported platforms mirrors the diversity in the personal characteristics of the individuals themselves. Indeed, with mobile technology playing such an inherently integral role in this mLearning system, the device capabilities and features may have a major bearing on not only service delivery, but also on the overall learning experience of the system users. Therefore, in order for the services supported within this architecture to achieve their full educational potential and to accommodate the huge diversity and dynamicity of the environments within which these services are to be delivered, the service content must be adapted to a highly contextualised and personalised configuration, ensuring that the proper information is delivered in the optimal

format to maximise its effectiveness. To facilitate the harnessing and utilisation of device capability and preference information (CPI), the WURFL, the Wireless Universal Resource FiLe [28] and its associated Wireless Abstraction Library by Luca (Passani) – Next Generation (WNG) [29, 30] were incorporated into the system’s WNGAgent so as to facilitate the service content contextualisation. WURFL is itself essentially a database containing information pertaining to the capabilities and features of a vast multitude of mobile devices. This database, and its associated API, enables service facilitators / adaptation entities –in this case the WNGAgent– to generate a specification of the capabilities and features for any requesting device based on a user agent string, which specifies some basic details about the device. Device capabilities of particular interest are those identifying the preferred content format for presentation within the browser of the device. WNG was created to address the issue of multi-serving web content in a number of formats without having to create multiple versions of content. Instead of building separate versions of certain content, a document is composed of information identified by WNG tags. The information tagged within this document can then be retagged in the relevant format, depending on the mark-up identified by the WURFL system [29]. By exploiting the WURFL’s ability to discern the capabilities of requesting devices, and the WNG’s functionality to determine the preferred mark-up of particular devices, the WNGAgent can render the requested content in the most appropriate format. As well as this, the WNGAgent also determines the device’s support for various file types. The lecturer may upload content in the form of PDF, audio, video files etc. By utilising the WURFL’s mechanism capability to determine the device’s level of support for particular file types, the WNGAgent can identify the content types to advertise to the requesting user, ensuring that the user is only presented with service content suitable to the device being utilised.

While it is essential that the context of the user’s mobile device be taken into account when adapting presented services, the user’s own personal context should also be considered when delivering these services. Indeed, within educational institutions, this particular aspect gains even greater credence. Within educational institutions, divisions already exist, segregating students within different faculties, within different courses of study, or indeed within different classes. These natural divisions provide an obvious method of classifying students and as such a means of targeting services to particular cohorts, as in many cases, the content of some services will only be applicable to certain small groups. Figure 4 illustrates the composition of user profiles within this system. All user information is stored within a DB4O (Database for Objects) database [31]. DB4O is an object-oriented database management system (DBMS), which supports the storage of pure Java objects. As this entire system is implemented in Java, this object-oriented approach was well suited to the storage of useful information, in this case relating to system users. When a new user profile is

created, it is created in the form of a Java object, which is itself an instance of simple User class.

The composition of the User class, as illustrated in Figure 4, consists of a number of useful elements. For the most part each profile consists of a number of simple string objects such as the userName, password etc. Each piece of information plays a vital role in the contextualisation and delivery of services, as well as the management of information within the InfoStation. When a user initiates the PAA, they supply the PAA with a number of pieces of information, which enable the PAA to initiate a service request. The userName and password play an obvious role in the Authentication, Authorisation and Accounting (AAA) procedure, which enables the InfoStation to validate an incoming service request. The InfoStation executes the AAA procedure before examining the academic information contained within a specific user profile. The userCourse and userYear attributes enable the InfoStation to discern the educational context of the user by gathering together a list of classes the user attends. Within this system, when a service instance is created, the specific applicable classes are also specified. Therefore, on receipt of a user service request, the InfoStation can cross reference the service list with the list of classes undertaken by the user, and as such, gather the list of services applicable to that individual user. This service offering is then provided to the user. Once the user selects the requisite service, the InfoStation ensures that any delivered service content is contextualised and adapted to suit the operating environment within the requesting mobile device. Within the following section, the system component interactions in delivering the mLecture service are detailed.

IV. MLECTURE SERVICE DELIVERY The mLecture service exists as one of the core

services within this system. While initially this service could be used as a supplementary tool to aid the traditional learning experience, it could also be utilised to facilitate more holistic/opportunistic distance learning. Within a traditional lecture setting, it is often the case that a lecturer will make various ancillary learning resources

available, in order to aid the students comprehension of the presented information, or indeed to enable them to pursue additional knowledge of their own volition. Usually these supplementary materials consist of sets of notes accompanying the lectures, or additional lab materials etc. In the case of the mLecture service facilitated through this system, a lecturer can upload these additional learning resources (e.g. text documents, audio or video files) pertaining to the lecture, perhaps supplying a pod-cast or video-cast of the lecture itself. This can serve to greatly assist the student’s assimilation of information, as students can regulate the pace at which they proceed through the information and if necessary re-cycle back through the lecture. This ability to moderate the pace at which they cycle through the presented information ensures that the presented material is more accessible for learners of varying learning styles.

As was discussed in the previous section, services are offered to students based on their own personal context

Figure 5: The mLecture service delivery.

Figure 4: The user profile composition.

(as specified within their associated user profile). This is particularly important within the educational domain. The sequence diagram in Figure 5 depicts the interactions between the functional entities involved in the mLecture service provision. The initial entity interactions, when the mobile user first enters within the range of an InfoStation, are concerned with the AAA processing of the user’s presented credentials, and subsequent selection of service. The PAA forwards the user’s service request to the InfoStation within a CFP ACL message. The Connection Advisor agent (CAAgent) within the InfoStation examines this request and sets about discerning the service applicable to that user. The list of applicable services passed to the PAA is based on the educational context of the user (as detailed in the previous section). On receipt of this list, the PAA displays the list to the user, who may then select relevant service. The format of the presented service content is detailed to the user giving them the opportunity to choose which format they wish to harness, whether through adapted web content, audio, video or indeed as a static document format, such as PDF. Again, the specification of these content formats within the service listing depends on the capabilities of the user’s accessing device. It is the responsibility of the InfoStation to discern the capabilities of the target device and offer the appropriate content. Once the user has selected the particular mLecture service content they wish to access, the PAA forwards on an ACCEPT_PROPOSAL ACL message containing the details of the service request. The InfoStation’s Content Adaptation Agent examines the user’s current device profile and discerns the optimal format in which to deliver the service content. This must be undertaken before performing any necessary adaptation procedures to ensure the content is in the optimal format for display on the target device.

V. CONCLUSION An InfoStation-based multi-agent system supporting

the delivery of contextualised mLearning services within educational environments together with enhancements of this architecture have been presented. This included an outline of its structure built upon the JADE platform and incorporating contextualisation mechanisms such as WURFL and WNG. In the discussion about the evolution of mLearning and its impact on teaching practices, particular attention was paid to the personalisation of services within an educational context. Finally, the delivery of an mLecture service was detailed, highlighting the main interactions between the agents involved.

VI. ACKNOWLEDGMENTS

The authors wish to acknowledge the financial support of the Irish Research Council for Science, Engineering and

Technology (IRCSET) and partially of the NPD of Plovdiv University under Grant No. NI11-FMI-004.

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