Sharing Distributed Resources in LearnWeb2.0 - Semantic Scholar

Sharing Distributed Resources in LearnWeb2.0 Fabian Abel, Ivana Marenzi, Wolfgang Nejdl, and Sergej Zerr L3S Research Center, Leibniz University Hannover, Germany {abel,marenzi,nejdl,zerr}@L3S.de

Abstract. The success of recent Web 2.0 platforms shows that people share information and resources within their social community and beyond. The use of these platforms in an e-learning context has been limited, though. One reason for this is the fact that most of these platforms only support specific media types, and teachers trying to assemble learning resources have to login to and use several Web 2.0 tools at once to access all relevant resources. In this paper, we present LearnWeb2.0, an integrated environment we implemented for sharing Web 2.0 resources, which improves support for learners and educators in sharing, discovering, and managing learning resources distributed across different platforms. LearnWeb2.0 integrates ten popular resource sharing and social networking systems, and provides advanced features for organizing and sharing distributed learning resources in a collaborative environment. Keywords: resource sharing, distributed learning resources, knowledge management, LearnWeb2.0.

1 Introduction The success of Web 2.0 and specific platforms such as YouTube, Flickr, and Delicious demonstrates that people are willing to share knowledge and resources with other people. Popular resource sharing systems allow users to upload and share content, but do not focus on educational resources. In [1], Petrides et al. point out that there is a need for platforms, which allow us to share open educational resources and inspire a culture of continuous improvement of these resources. In addition, sharing of educational material requires an environment, which permits the storage of resources in different formats. Typically, different Web 2.0 infrastructures focus only on particular media types, videos in YouTube, pictures in Flickr, or bookmarks in Delicious, even if these resources belong to one and the same context [2]. Thus, despite the variety of available resource sharing systems, linking distributed educational resources related to the same context is still difficult. In this paper, we present LearnWeb2.0, an environment for sharing educational resources by integrating existing Web 2.0 systems. In line with the findings presented in [3], which discusses how the integration of popular Web 2.0 services into learning processes can foster active participation, LearnWeb2.0 integrates popular resource sharing systems and social networking systems to provide an environment that improves support for learners and educators in sharing, discovering, and managing learning resources. Our main contribution is the LearnWeb2.0 platform and system, U. Cress, V. Dimitrova, and M. Specht (Eds.): EC-TEL 2009, LNCS 5794, pp. 154–159, 2009. © Springer-Verlag Berlin Heidelberg 2009

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which integrates ten popular Web 2.0 services to enable sharing, discovery, and management of distributed learning resources. LearnWeb2.0 provides various innovative features: 1) a personal learning space offering a seamless overview of the entire set of learning resources distributed across various Web 2.0 repositories, 2) sharing through standing queries, where users are notified whenever a new learning resource matches the query, 3) collaborative aggregation of different learning resources via an intuitive drag-and-drop interface, 4) integration of the user's social networks from different Web 2.0 services, 5) a browser plug-in that enables users to easily share learning resources via drag-and-drop operations.

2 LearnWeb2.0: Architecture and Functionalities 2.1 Architectural Design LearnWeb2.0 consists of a Web application, the LearnWeb2.0 platform, and the LearnWeb2.0 Browser Plug-in (Fig. 1). The Web application provides a Personal Learning Space which supports users in discovering, sharing, and organizing distributed resources. LearnWeb2.0 uses existing Web 2.0 services as storage infrastructure, which means that core functionalities implemented by the following modules are mapped to the services preferred by the individual user. The Search and Exploration module provides a uniform interface that enables the user to search and discover resources (videos, slides, textual documents, etc.), which are distributed across the integrated Web 2.0 services. The Annotation and Aggregation module enables users to organize learning resources, for example, by tagging or grouping these resources. The Upload and Sharing module enables users to store and

Fig. 1. (a) LearnWeb2.0 Web platform and (b) the LearnWeb2.0 browser plug-in

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share resources from their local Desktop or from the Web. Resources are stored in the Web 2.0 system, which is appropriate for the given media type and favored by the user. These modules are not only used by the LearnWeb2.0 platform, but are made available as web services so that other authorized applications, for example, our browser plug-in, can use this functionality. The Browser Plug-in facilitates upload and sharing of new resources as users can simply drag a resource from their Desktop or from the Web onto the plug-in icon to initiate the upload. Functionality provided by the modules described above is based on three further modules: The Web 2.0 Service Adapter module maps LearnWeb2.0 functionalities to specific Web 2.0 services. Currently, the system provides adapters for all 10 services. Further service adapters can be easily added. LearnWeb2.0 users do not have to login to each Web 2.0 system separately, but can authorize LearnWeb2.0 to access their preferred services (single sign on). The Authorization component is also used when third-party applications try to access LearnWeb2.0 Web services, and adheres to the OAuth5 protocol and REST principles. By integrating different Web 2.0 services, LearnWeb2.0 overcomes shortcomings of existing resource sharing systems. One important aspect is access control: if a user bookmarks a Web page at Delicious she can mark the bookmark as private or public. In this way users can share their bookmarks with selected LearnWeb2.0 users fulfilling a flexible set of constraints. 2.2 LearnWeb2.0 Functionalities LearnWeb2.0 is implemented using the PHP programming language and the CakePHP framework, which provides support for Web application development in accordance with the MVC paradigm. PHP wrappers are provided for many Web 2.0 system API's, but not for all: We had to implement new API’s for GroupMe! and Slideshare. Another complex issue is authentication. Not all tools provide token-based authentication mechanisms; Slideshare and Delicious for example directly need user credentials such as login and password to access the API functionality. To enable single sign on for those tools as well, we save these credentials in an encrypted form on our server and thus are able to provide a uniform authentication interface to all Web 2.0 tools through the LearnWeb2.0 GUI and Web services. To make the system scalable, we implemented a caching mechanism which dramatically reduces the number of API calls per user. It was also necessary to work around the usage constraints of some tools, e.g. Delicious, which only allow a limited number of calls to API methods. This made it possible to provide a seamless integration of the Web 2.0 applications, using the Web 2.0 Service Adapter as integration driver (authorization, search, upload and social network services for the integrated platforms) for the different Web 2.0 tools shown in Table 1. Search and Exploration of Learning Resources. LearnWeb2.0 provides users with a generic search interface for resource discovery across various Web 2.0 services, including LearnWeb2.0 itself. Uniform authorization provided by LearnWeb2.0 enables learners to pose queries to the resources distributed in Web 2.0 platforms in a similar way as with a desktop search engine on a local machine.


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Table 1. Core features of LearnWeb2.0 and Web 2.0 services used to realize the features

The Learnweb2.0 feature provides an integrated view on the search results obtained from all integrated Web 2.0 services. Using the advanced search functionality, the learner can select a set of resources based on a common property like a tag, a file type, a timestamp or combinations thereof. On the server side, search requests for the integrated services are generated from the user’s query so that they correspond to the search functionalities supported by the particular service (see Table 1). Responses from the different services are combined into a single RSS atom feed which is made available to the user along with a list of search results. LearnWeb2.0 preserves the presentation of search results as provided by the original services. Typically a search result contains a title, an image and optionally a more detailed description. The feed can be used as a standing query in any RSS reader so as to monitor the appearance of new resources responding to the query. These capabilities provide a seamless view on all resources stored in the various Web 2.0 accounts of users, thereby creating their Personal Web 2.0 Learning Space. In order to support collaborative searching, LearnWeb2.0 provides automatic resource annotation. Once a search result is displayed in LearnWeb2.0, it is automatically tagged with the corresponding query terms. These tags can then later be used by other users to search and explore the learning-resource space available in the LearnWeb2.0 environment. LearnWeb2.0 can also access a user’s social network information from the integrated Web 2.0 applications. A LearnWeb2.0 user’s social network is thus made up of all his/her connections specified in the different Web 2.0 systems integrated into LearnWeb2.0. This enables users to explore and gather additional resources by browsing the corresponding profile pages of their friends. Annotation and Aggregation of Learning Resources. References to selected resources are stored in the LearnWeb2.0 repository. In this repository, the user can annotate a resource with additional metadata in Dublin Core format. A reference to one and the same resource can be added to the repository in different learning contexts. To support resource aggregation, LearnWeb2.0 relies on GroupMe! functionality. Users can

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create groups of learning resources to bundle resources that belong to the same learning context. In order to support collaborative aggregation, it is possible for several users to share a group and contribute resources to this group. These groups are fully visualized, i.e. images include previews, videos can be directly watched from the system. Resources, and groups of resources, in LearnWeb2.0 can be bookmarked, tagged, rated and discussed by other users who are allowed to access them. Hence, the LearnWeb2.0 community can collaboratively identify the best learning resources for specific learning domains. Comments on learning resources can further be used by the authors to improve their resources. Upload and Sharing of Learning Resources. The Web is not the only place where users can find relevant materials. Useful resources can also be located on the user's computer or are acquired through other devices such as a camera. Using LearnWeb2.0 users can directly upload a resource from their computer or an external source to a suitable Web 2.0 tool and enrich it with useful annotations. Users can carry out resource upload either through the LearnWeb2.0 GUI or via the LearnWeb2.0 browser plug-in (currently supported for Firefox), both of which provide upload functionality as drag-and-drop activity from Desktop or Web resources to the LearnWeb2.0 plug-in icon included in the browser.

3 Related Work Web 2.0 and Education. The authors of [3] discuss how the integration of popular Web 2.0 services into education can stimulate active participation of learners in the learning process. In line with these findings and based on requirements identified in [4], LearnWeb2.0 integrates various Web 2.0 services to provide an environment for sharing educational resources. The demand of platforms that allow users to share open educational resources is discussed in [1]. LearnWeb2.0 provides such a platform but goes one step further as it supports (i) both kinds of users, educators and learners, and (ii) both traditional educational resources and resources originally not intended for education. As resources come in different formats, LearnWeb2.0 supports all appropriate media types, and does so in an integrated way, in contrast to mashUps such as Netvibes or iGoogle, which provide access to different Web 2.0 services in a single environment, but keep these services separated [5]. The need for assistance in multiple, flexible filing and searching facilities to offer enhanced attributes in users’ desktops was identified in [6]. LearnWeb2.0 expands this concept into a virtual desktop, spread over a number of Web 2.0 services that manage these resources. Search and Sharing. Recent studies have shown that social search techniques can improve the effectiveness of the Web search. SearchTogether [7] is such an interface for collaborative search. In LearnWeb2.0 we enable users to store, rate, comment, tag and reuse the most successful queries. By representing the search result page as an RSS feed, LearnWeb2.0 implements a standing query mechanism, useful for collaboration on common tasks. LearnWeb2.0 also enables users to share queries and other resources, and collaboratively organize and use them in groups [8].


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4 Conclusions and Future Work In this paper we presented the LearnWeb2.0 environment, which supports learners and educators in sharing, discovering, and managing learning resources that are spread across different Web 2.0 platforms. LearnWeb2.0 aggregates resources and uses functionalities from ten different Web 2.0 services and propagates LearnWeb2.0 actions back to these services. LearnWeb2.0 thus provides a personal learning environment offering a seamless overview of the entire set of relevant resources distributed over the different platforms. Collaborative aggregation of learning resources into groups is supported via simple drag-and-drop operations. Next steps include the evaluation of LearnWeb2.0 at our university, and the implementation of new features focusing on access control and notification of users as regards interesting resources, all of which improves awareness during collaborative search. Acknowledgments. The work on this paper has been partially sponsored by the TENCompetence Integrated Project. Contract 027087.

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Petrides, L., Nguyen, L., Kargliani, A., Jimes, C.: Open Educational Resources: Inquiring into Author Reuse Behaviors. In: Proc. of 3rd European Conference on Technology Enhanced Learning (EC-TEL), pp. 344–353. Springer, Heidelberg (2008) Demidova, E., Kärger, P., Olmedilla, D., Ternier, S., Duval, E., Dicerto, M., Mendez, C., Stefanov, K.: Services for knowledge resource sharing & management in an open source infrastructure for lifelong competence development. In: Intl. Conference on Advanced Learning Technologies (ICALT), Niigata, Japan (2007) Ullrich, C., Borau, K., Luo, H., Tan, X., Shen, L., Shen, R.: Why Web 2.0 is good for learning and for research: principles and prototypes. In: Proc. of 17th Intl. World Wide Web Conference (WWW), Beijing, China, pp. 705–714 (2008) Marenzi, I., Demidova, E., Nejdl, W., Zerr, S.: Social software for lifelong competence development: Challenges and infrastructure. International Journal of Emerging Technologies in Learning (iJET), 18–23 (2008) Thang, M., Dimitrova, V., Djemame, K.: Personalised Mashups: Opportunities and challenges for user modeling. In: Conati, C., McCoy, K., Paliouras, G. (eds.) UM 2007. LNCS (LNAI), vol. 4511, pp. 415–419. Springer, Heidelberg (2007) Bischoff, K., Herder, E., Nejdl, W.: Workplace learning: How we keep track of relevant information. In: Duval, E., Klamma, R., Wolpers, M. (eds.) EC-TEL 2007. LNCS, vol. 4753, pp. 438–443. Springer, Heidelberg (2007) Morris, M., Horvitz, E.: SearchTogether: An interface for collaborative web search. In: Proceedings of 20th ACM Symposium on User Interface Software and Technology (UIST), Newport, USA, vol. 3/12 (2007) Abel, F., Frank, M., Henze, N., Krause, D., Plappert, D., Siehndel, P.: GroupMe! Where Semantic Web meets Web 2.0. In: Aberer, K., Choi, K.-S., Noy, N., Allemang, D., Lee, K.-I., Nixon, L.J.B., Golbeck, J., Mika, P., Maynard, D., Mizoguchi, R., Schreiber, G., Cudré-Mauroux, P. (eds.) ASWC 2007 and ISWC 2007. LNCS, vol. 4825, pp. 871–878. Springer, Heidelberg (2007)