The Benefits of Geo-Tagging and Microblogging

in m-Learning: a Use Case

Christian Safran

Institute for Information Systems

and Computer Media

Graz University of Technology

Inffeldgasse 16c, A-8010 Graz,

Austria +43 (316) 873 5668

csafran@tugraz.at

Victor Manuel Garcia-

Barrios Institute for Information Systems

and Computer Media

Graz University of Technology

Inffeldgasse 16c, A-8010 Graz,

Austria +43 (316) 873 5640

vgarcia@iicm.edu

Martin Ebner

Social Learning / Computer and

Information Systems

Graz University of Technology

Inffeldgasse 16c, A-8010 Graz,

Austria +43 (316) 873 5640

martin.ebner@tugraz.at

ABSTRACT

The recent years have shown the remarkable potential use of Web 2.0 technologies in education, especially in the context of informal learning. The application of Wikis for collaborative work is one example for this theory applied. The support of learning in those fields of education, which are strongly based on visual location-based information, could also benefit from Geo-Tagging, a technique that has become popular lately. This paper presents first development results on the combination of these two

concepts into a geospatial Wiki for higher education, TUGeoWiki. Our solution proposal supports mobile scenarios where textual data and images are managed and retrieved during m-Learning in-

the-field as well as some desktop scenarios in the context of collaborative e-Learning. Within this scope, one critical issue arises while adding and updating textual information via the collaborative interface, which can be cumbersome in mobile scenarios. To solve this problem, we integrated another popular

concept into our solution approach, Microblogging. Thus, the information pushed via short messages from mobile clients or microblogging tools to our m-Learning environment enables the creation of Wiki-Micropages as basis for subsequent collaborative learning scenarios.

Categories and Subject Descriptors

H.3.5 [Information Storage and Retrieval]: Online Information Services – Web-based services

H.5.3 [Information Interfaces and Presentation]: Group and Organization Interfaces – Computer-supported cooperative work

K.3.1 [Computers and Education]: Computer Uses in Education – Collaborative learning

General Terms

Design, Experimentation.

Keywords

m-Learning, Wiki, microblogging, geotagging.

1. INTRODUCTION A remarkable movement towards geo-locating software has occurred in the last months, marking a renaissance of location-based mobile applications. One of the reasons is the availability of a variety of mobile devices providing integrated GPS1 receivers. Another reason is the rising number of mashup applications accessing freely available mapping material via Web services, and

thus providing added value for geospatial information. Almost in parallel, Geotagging appeared. This technique denotes the marking of a digital resource with geographical coordinates and is mostly used for images. In the case of images these coordinates can be integrated into the image by using a set of Exif2 Besides valuable discussion about privacy issues, this additionally marked information offers new possibilities for teaching and learning, especially in fields which strongly depend on geolocated data,

such as civil engineering, geosciences or archaeology. The combination of geotagging with other technologies connected to Web 2.0 provides a further contribution to e-Learning 2.0, as defined by Stephen Downes [1].

This paper gives a short overview on a solution to enhance learning by integrating (mobile) geotagging of images with collaborative authoring. The implementation of our solution proposal, called TUGeoWiki, supports m-Learning in reference to

two scenarios: (i) a mobile application scenario, which focuses on information retrieval and real-time sharing of resources, and (ii) a desktop application scenario, which supports informal e-Learning by providing a collaborative authoring tool. For the concrete fields of education mentioned above, TUGeoWiki represents a tool that

1 GPS - Global Positioning System 2 Exif – Exchangeable Image File Format

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supports field trips and excursions from the preparation phase, throughout the field trip itself and until the review.

It is worth mentioning at this point that so far, only using the Web-based collaborative interface for the provision of textual information in mobile scenarios has shown to be cumbersome.

Thus, to solve these user interaction problems within the mobile scenario, we propose to incorporate the novel Web 2.0 concept of Microblogging into the work with a Wiki.

The remainder of this paper is structured as follows. First some topics of interest in the context of this research are presented and discussed in relation with TUGeoWiki. Subsequently the development and functionality of the TUGeoWiki are presented and design decisions explained. The next chapter is focussed on

the expansion of the existing solution with the integration of microblogging. Finally a summary and some outlook on future work are given.

2. TOPICS IN CONTEXT The development of TUGeoWiki was based on related work from

three areas: geotagged images, Wikis for collaborative learning, and mobile learning.

In subjects like civil engineering, geosciences, architecture etc.

higher education is strongly based on visual information. As pointed out by Brohn, the “language of intuition is visual, just as

the language of analysis is abstract and symbolic” [2]. Taking civil engineering as an example for such a subject, several research activities have been able to point out the importance of visualisations, animations, as well as interactions for civil engineering [3-5]. Especially for explanations of highly complex engineering models, new technologies offered a completely

different way of teaching and learning. Still, visualisations lacked at one particular point: the connection of the abstract engineering model and the real world. The major competence of any practical engineer is assumed to be the capability of abstracting an appropriate model from nature in order to develop a quantifiable mathematical model. This allows us to state that the knowledge about the particular environment where a building will be placed is highly important. Hence, a connection of visualisations and real-world locations can be achieved by using geotagged images.

Considering another relevant topic, Wikis, as online collaboration tools, were introduced by Leuf and Cunningham in 1995 [6]. The

term itself is derived from the Hawaiian word wikiwiki, meaning quick. The technology has been designed to provide a simple tool for knowledge management, which places at the disposal of all users a smart possibility to mutually create and edit content online. In addition, individual users may use the functionality of version history to retrace all content modifications and, if desired, revert to earlier content versions. As such, a Wiki is an easy-to-use application for the collaborative management of online

content. These characteristics have made Wikis a tool of choice in informal learning [7]. The importance of Wikis in e-Learning has lead Stephen Downes to list them as one of the basic technologies of e-Learning 2.0 [1].

Mobile learning (abbreviated, m-Learning) is the combination of e-Learning and mobile computing, and promises the access to applications that support learning anywhere, anytime [8]. Meanwhile, due to technological progress, hardware is considered a solved problem. However, innovative, affordable and usable software remains the greatest challenge. Handhelds, for example,

should support project-based learning in context, that is, using the mobile device as an integral part of a learning activity [9]. One of the central advantages of mobile learning is ongoing assessment and possible feedback, as demonstrated in [10]. In higher education, m-Learning is especially interesting for fields of study

which rely on education on-site respectively in-the-field. One example for the use of mobile technologies for teaching purposes is the EU research project RAFT (Remote Accessible Field Trips), which was conducted from 2002 to 2005. The target of this project was the support of school classes with virtual excursions using portable Internet-conferencing tools [11].

3. A GEOSPATIAL WIKI FOR M-

LEARNING The previous chapters introduced two relevant aspects: the importance of visual information, particularly location-related visual information, for several fields of education as well as the advantages of collaborative learning with Wikis. Along these lines, this chapter introduces firstly the most relevant traits of the

proposed solution, and gives then an overview over the solution itself, TUGeoWiki.

3.1 Why lightweight, geotagged and mobile? In order to combine the two aforementioned technological aspects, we designed and developed a solution approach for a

lightweight, geotagging-based and mobile learning environment applying a geospatial Wiki.

The term lightweight expresses our efforts to implement only the

basic features of a geographical information system (GIS) for learning, namely (a) collecting, and (b) displaying geotagged data (also as map overlays). We consider further features of GIS, such as data analysis and modelling, to be out-of-scope, as they are only necessary for geosciences professionals. Moreover, our notion of lightweight embraces also our intent towards unobtrusive user interaction features based on well-known software practices. Especially as far as the technology acceptance

of mobile applications is concerned, lightweight also refers to the overall costs, as low-cost applications with low maintenance efforts have turned out to be best accepted [12].

Further, our solution proposal concentrates on location-related information, and thus on learning scenarios where such information is an essential part of the curriculum. In those cased, students can benefit from a clearly defined relation of learning material to a geographic location (geotagging-based).

Finally, the term mobile describes our intention to offer access to information and learning material “in-the-field” in order to enhance “on-site learning” whenever applicable. It is worth stating at this point that within the context of our solution approach, we focus on mobile phones and PDAs3 instead of other mobile technologies in order to stick with the primary goal of a

lightweight system, as such devices are widespread and handy to carry in the field. Moreover, the user of mobile technology should enable us to foster collaborative activities of learners wherever possible, whenever possible.

3.2 TUGeoWiki Our solution approach, the TUGeoWiki system, is a geospatial Web-based mobile application that aims at supporting the learning

3 PDA - Personal Digital Assistant

scenarios given so far. This section gives an overview on the main features of the system, for more details please refer to [13]. The TUGeoWiki system is based on the well-known open source MediaWiki implementation. We have chosen MediaWiki for two reasons.

First, it provides two well-defined mechanisms for extension of functionality: special pages and templates. Special pages are

pages without Wiki content, which are generated on demand and are used to provide additional tools for users, e.g., file upload [14]. Templates are pages created for transclusion purposes, and usually contain repetitive materials or blocks of information (e.g., infoboxes) [15].

And second, the user interface of MediaWiki is probably the best-known Wiki user interface, among others, due to the immensely broad use and high popularity of Wikipedia [16].

TUGeoWiki modifies the MediaWiki paradigm of pages for the individual entries in order to define places, which are relayed to geographical coordinates, and thus represent real-world locations. In our terminology place thus defines the entity in the system, while location denoted the actual geographical entity. This modification is achieved by using MediaWiki’s special pages to

create location-based entries as well as templates to display them. Figure 1 depicts the concept of creating a place. These templates are designed as mashups, thus extending the Wiki entries with mapping material from Google Maps or Microsoft Live Search Maps. Additionally, a hyperlink to the MediaWiki extension Geohack provides access to numerous other map sources [17].

Figure 1: General notion for creating places in TUGeoWiki

This Wiki application can be used in classroom or remote learning scenarios to provide a tool for collaborative activities on geospatial information, resulting in two application scenarios: a “desktop application scenario” and a “mobile application scenario”.

The desktop application scenario is based on collaborative authoring with the Wiki and fosters process-oriented learning and

task-based learning. Possible use cases in this context are the preparation for field trips as well as post-processing and review of the information gained in such an excursion. The focus of this scenario is set on collaborative authoring in order to support informal learning on the topics of such an excursion.

The mobile application scenario provides access to the learner’s current location by querying internal or external GPS sensors. The coordinates retrieved from the GPS sensors are used in

TUGeoWiki to search for places in the vicinity of the current location or to create a new place in the Wiki and start collaborative learning about the topics of the current location. The main goal behind this scenario is to satisfy an information-need just-in-time concerning the current location as well as enabling

real-time sharing of resources (mainly images) concerning the location. Due to the restrictions of the user interface (cf. i.e. [18]), collaborative authoring in this mobile scenario is a non-trivial task, and thus the editorial work on places has been restricted to

The mobile application scenario provides access to the learner’s current location by querying internal or external GPS sensors. The coordinates retrieved from the GPS sensors are used in TUGeoWiki to search for places in the vicinity of the current location or to create a new place in the Wiki and start collaborative learning about the topics of the current location. The main goal behind this scenario is to satisfy an information need

just-in-time concerning the current location as well as enabling real-time sharing of resources (mainly images) concerning the location. Due to the restrictions of the user interface (cf. i.e. [18]), collaborative authoring in this mobile scenario is a non-trivial task, and thus the editorial work on places has been restricted to the creation and annotation of so-called place stubs. Place stubs (also called article stubs) can be seen as temporary mini-place objects that learners use at their mobile devices, and after

submitting them to the Wiki server, they can be described in more detail. Additionally for the mobile application scenario, TUGeoWiki provides a feature to create geotagged images with the mobile phone’s camera and embeds the GPS coordinates in the Exif headers of the image files. In a separate step, these images (or images created with any other application for geotagging images) can be uploaded and relayed to existing places or used to provide an article stub for a new place in an arbitrary location around the corresponding coordinates.

We have stipulated these two aforementioned scenarios in order to improve learning activities in-the-field and on-site by supporting

several steps in such learning journeys, i.e., activities before and after the journey with the desktop scenario and activities during the journey with the mobile scenario.

The component architecture of the TUGeoWiki system as well as the interactions among the individual parts (with focus on the mobile scenario) is shown in Figure 2. The mobile device (mobile phone or PDA) is equipped with the TUGeoWiki client and a Web browser. The client retrieves the current coordinates of the device either from an internal GPS sensor, or, via Bluetooth, from an external sensor.

The client relays requests for upload of images to the mobile browser or directly to a server side application programming

interface (API). Requests for information about the current location or requests for creating a new place for the current

location are always relayed to the mobile browser. The browser is mainly used to access the adapted MediaWiki on the TUGeoWiki server side, which shares a common database with the API. For each new entry, the Wiki displays a place template, which embeds a Google Map, and links (relaying the place’s coordinates) to the Geohack extension as well as Google Maps and Microsoft Live Search Maps.

Figure 2: TUGeoWiki component architecture – mobile scenario

A first version of this mobile client has been implemented using

Java Mobile Edition (Java ME) to provide the basic functionality for a wide number of mobile devices. On the one side, this Java client provides access to internal GPS sensors or Bluetooth GPS sensors as well as to the mobile device’s camera, and on the other side, it forwards information about the current location of the device to the mobile browser. In turn, the mobile browser is used to access the TUGeoWiki server side application. The Java ME application acts only as a tool to provide data for the browser but does not access the TUGeoWiki server itself.

Additionally, native applications for Symbian OS (respectively the S60 platform) as well as Android have been implemented.

These applications provide the same features as the Java client, but are using a different software design. They access a server side API which is used to query, add and modify the Wiki data without the use of a Web browser, offering an alternative mobile user interface. An iPhone client for the TUGeoWiki system is currently under development.

4. MICROBLOG INTEGRATION In the previous chapter, the two possible application scenarios for TUGeoWiki, mobile and desktop, have been described. It has been shown that the mobile scenario is mainly focused on the satisfaction of ad-hoc learning needs as well as on proactive information push to the Wiki, rather than on collaborative editing of contents. So far, the examples given for such an information push were the creation of place stubs and the extension of places with geotagged images. However, this approach lacks of a possibility to easily share information about/across images via the

mobile application. For any textual information added to individual locations, the standard MediaWiki edit functionality must be accessed with the mobile browser. First evaluations with a small group of users showed that this functionality was perceived as cumbersome and avoided as far as possible. These reactions of the evaluation subjects are assumed to be a result of

the typical mobile phones limitations regarding their small screen

sizes and the complexity of writing with mobile or virtual keyboards. In order to solve this problem and to simplify the interactions with the Wiki, we propose the usage of an alternative technique, which is based on the principle of adding (small) notes to existing articles as a foundation for collaborative activities within our desktop application scenario. In analogy to the Microblog Paradigm, short messages are sent by the users and integrated into the Wiki, creating Micropages.

4.1 The Notion of Micropages Due to the fact that the number of mobile devices connected to the World Wide Web is growing incredibly fast, microblogging has become one of the most interesting innovative applications nowadays. Microblogging can be seen as a variant of blogging, where small messages, usually not longer than 140 characters, are posted instantly and on-demand to microblogging service. Microblogging can be defined as “a small-scale form of blogging,

generally made up of short, succinct messages, used by both

consumers and businesses to share news, post status updates, and

carry on conversation” [19]. As far as the user-intentions are concerned they can be categorized in the following four types: daily chatter, conversations, sharing information, and reporting news [20]. Further, research work has pointed out that microblogging is extremely useful for the fast exchange of thoughts, ideas and information sharing [21]. Considering the

growing importance of mobility and mobile applications, e.g., Twitter (the largest microblogging platform worldwide) became one of the prime examples for Mobile 2.0 [22].

To characterise the notion of Wiki pages that are based on small individual information pushes, we apply the term micropages. Thus, micropages are the Wiki analogy of microblogs, which describes our approach focusing on smaller parts of information.

Figure 3: Example for a TUGeoWiki micropage with one annotation

In a microblog, brief text updates are used as status messages to write up information for friends and other “followers”. By encouraging shorter posts, microblogging can fulfil a need for a faster form of communication [20]. Within the scope of this paper, we propose to use micropages as Wiki pages that are built out of short individual annotations on the topic of the page. In

TUGeoWiki, each of these topics is a location, and each page is a place. Figure 3 depicts one example for a micropage in TUGeoWiki containing one annotation.

The creation process of such a micropage by means of the Wiki’s special pages is depicted in Figure 4. A short message is created (usually on a mobile device) and geotagged with the user’s current location. A special page is used to find an appropriate place or create a new one, and to append the message at the end of the micropage.

Figure 4: General notion for creating micropages

The building parts of a TUGeoWiki micropage are derived from the received messages and always appended in chronological order (earliest on top) instead of in reverse chronological order (as in weblogs) to better address the Wiki page paradigm. These parts are furthermore tagged with some metadata, such as the author’s username, the date and time of the post.

Unlike microblogs, micropages are not intended to serve as means for synchronous communication, but to share only the concept of

information push of short messages. Further, a new micropage is not intended to represent a final content in the Wiki; rather (as for Wiki contents in general) it should be iteratively revised and improved to a final form via collaborative authoring. In concrete, micropages represent stubs for content in a Wiki, i.e., short annotations added to “sketch” the final page anytime, anywhere, and in the case of TUGeoWiki in-the-field and just-in-time.

4.2 Using Micropages with the Mobile Client Micropages are currently supported by TUGeoWiki’s Android and Symbian client. In both versions, the annotation attached to a

micropage has been implemented as for the upload of pictures. This process is described in the following.

In a first step, the user writes a message of 140 characters at most,

annotating her current location and chooses a distance from the current location for the search of suiting existing places. The client subsequently retrieves the current position from the built-in GPS sensor and relays it to the server, which returns the list of existing places within the chosen distance. On client-side, the user chooses either one of the existing places to annotate or creates a new place by entering a title. As previously mentioned, the message is then attached at the end of the place, accompanied by the user’s username as well as the date and time of the post.

Some sample screenshots of the TUGeoWiki Android client during the annotation workflow are shown in Figure 5. In the first

screenshot, at left side of the figure, a message is composed. The second screenshot shows the selection of the distance for searching existing places. The third screenshot displays the list of existing places retrieved. Finally, the fourth screenshot displays the message included in one of these places, in the Wiki at server side.

4.3 Integrating Microblogging Services Another possible source for the creation of micropages is the

integration of a so-called microblogging service. The analogy of micropages and microblogs inspired us to define an additional user interface. As stated before in this chapter, the annotation feature of the mobile client is purely intended for in-the-field and just-in-time annotations of geospatial information by sending short messages that describe the current location. Due to the fact that the location is determined via GPS coordinates, a later annotation of resources is not feasible. The problem in this

context arises when short annotations to already existing Wiki places are interesting for users after visiting the location, thus the following alternative user interaction might be of interest. In TUGeoWiki we integrated microblogging services that support Twitter posts. We have chosen the Twitter service because it is a well-known microblogging application with a well-defined API.

Figure 5: Screenshot of annotation feature of the mobile client

Taking into account this background, a very interesting aspect of

microblogging gained our attention: filtering information using a unique letter. This technique is referred to as hash tagging and has been introduced on several microblogging platforms. It is used for search queries or marking special content. Hashtags are a simple way of grouping messages with a “#” sign followed by a name or special code. [23]

Hashtags in microblogs are especially meaningful when used during a particular period of time, as “it not only allows

individuals to generate a resource based on that specific thematic,

while using the hashtag, but also bridges knowledge, and knowing, across networks of interest”. [23]

On the server side of the TUGeoWiki system, users may use a special page to mark a place as “microbloggable”. Moreover, individual users are provided a feature to append their Twitter

user names to their user profiles. This information is relayed to a Web service, which periodically scans the registered users’ microblogs for tweets containing the hashtag “#tgw”, indicating a TUGeoWiki annotation message.

This tweet must contain a second hashtag identifying the place via an URL. This hashtag is created using the URL shortening service bit.ly, which creates a 5-letter hash of an URL. So for example shortening the URL http://media.iicm.tugraz.at/geowiki/index. php/LKH_Klagenfurt_Neu results in the URL http://bit.ly/jBVbX. The corresponding hashtag, #jBVbX, is created for a place when marking it “microbloggable” and added to the TUGeoWiki template.

After identifying the TUGeoWiki-specific hashtags, the remainder

of the Twitter post is added to the corresponding TUGeoWiki place as a new annotation signed with the corresponding user name, date and time.

5. SUMMARY AND CONCLUSION Already during the phase of beginning to use Wikis for Education, it became rather clear that Wikis would generate a great benefit for collaborative activities among learner groups. A lot of research work has been carried out in order to show that process-oriented

learning is supported by Wikis in a very novel and smart way [24, 25]. The lack of existing tools to incooporate geotagged resources into learning in the field of civil engineering or architecture

lacking geographical information lead to the development of

TUGeoWiki. This approach provides a possibility to collaborate on geotagged information in a Wiki, based on the concept of places as individual articles. Moreover it provides means for learning in-the-field by uploading geotagged pictures and, with the help of microblogging, also geotagged messages.

In summary, it can be pointed out that our approach contributes to the enhancement of the collaborative activities between learners by enabling them to feed and compose geo-information with personal annotations (i.e., with the mobile part of the TUGeoWiki system) into a user-friendly environment for mutual authoring (i.e., the Wiki-based server side of our system).

In further studies and field experiments we will explore and evaluate how the underlying implementation framework finds applicability and usefulness in other research areas.

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Note: Blank parts in the submission are results of the blinding process for peer review.