ArchaeoApp Rome Edition (AARE): Making Invisible Sites Visible

e-Business Aspects of Historic Knowledge Discovery via Mobile Devices

Katharina Holzinger

, Gabi Koiner

, Primoz Kosec

, Markus Fassold

and Andreas Holzinger

Institute of Archaeology, Karl-Franzens University Graz, Graz, Austria

Research Unit Human-Computer Interaction, Institute for Medical Informatics, Statistics and Documentation, Graz, Austria

Keywords: Information Retrieval on Mobile devices, Knowledge Management, e-Business, Archaeology, Classics,

History, e-Business, Tourists.

Abstract: Rome is visited by 7 to 10 million tourists per year, many of them interested in historical sites. Most sites

that are described in tourist guides (printed or online) are archaeological sites; we can call them visible

archaeological sites. Unfortunately, even visible archaeological sites in Rome are barely marked – and

invisible sites are completely ignored. In this paper, we present the ArchaeoApp Rome Edition (AARE).

The novelty is not just to mark the important, visible, barely known sites, but to mark the invisible sites,

consequently introducing a completely novel type of site to the tourist guidance: historical invisible sites.

One challenge is to get to reliable, historic information on demand. A possible approach is to retrieve the

information from Wikipedia directly. The second challenge is that most of the end users have no Web-

access due to the high roaming costs. The third challenge is to address a balance between the best platform

available and the most used platform. For e-Business purposes, it is of course necessary to support the

highest possible amount of various mobile platforms (Android, iOS and Windows Phone). The advantages

of AARE include: no roaming costs, data update on demand (when connected to Wi-Fi, e.g. at a hotel, at a

public hotspot, etc. ... for free), automatic nearby notification of invisible sites (markers) with a Visual-

Auditory-Tactile technique to make invisible sites visible.

1 INTRODUCTION

1.1 Motivation for Research

Most sites that are described in tourist guides

(printed or online) are archaeological sites; we can

call them visible archaeological sites. Unfortunately,

even visible archaeological sites in Rome are barely

marked – and invisible sites are completely ignored.

The novelty of the ArchaeoApp Rome Edition

(AARE) is not just to mark the important visible but

barley known sites, but to mark the invisible sites,

consequently introduces a completely novel type of

site to the tourist guidance: historical invisible sites.

Moreover, AARE provides two modes: standard

tourist mode and a scavenger hunt modus, where it

makes use of powerful game-based learning

concepts (Mayo, 2009), (Hoffmann, 2009). This is

definitely an issue of e-Business since, according to

Marca et al. (2012), e-Business needs to cope with

the behaviour and requirements of Digital Natives

(Prensky, 2001), which is the generation growing up

with the Internet and having a great degree of

competence concerning the usage of mobile Web

services.

Consequently, digital natives are well informed

and assertive regarding products they want to buy

(Marca et al., 2012).

It is important to first understand the difference

between archaeological sites and historical sites. The

subject of Archaeology is to find and document

material of ancient cultures, including buildings,

houses, weapons, tools and even stuff that ancient

people threw away. However, the subject of History

is a different issue, namely the analysis of events

and actions. For that, historical sites are invisible

because they are one-dimensional. They only exist

in the fourth dimension, similar to an interface in a

Harris matrix (Harris, 1979). However, historical

sites are attached to special places.

A good example is the battle at the Milvian

Bridge (Speidel, 1986). This was the final battle

115

Holzinger K., Koiner G., Kosec P., Fassold M. and Holzinger A..

ArchaeoApp Rome Edition (AARE): Making Invisible Sites Visible - e-Business Aspects of Historic Knowledge Discovery via Mobile Devices.

DOI: 10.5220/0004074801150122

In Proceedings of the International Conference on Data Communication Networking, e-Business and Optical Communication Systems (ICE-B-2012),

pages 115-122

ISBN: 978-989-8565-23-5

 2012 SCITEPRESS (Science and Technology Publications, Lda.)

between the two rivals Maxentius and Constantine in

October of the year 312 AD. This battle is not only

significant as the start of the Constantinian Dynasty,

but can in some way also be seen as the beginning of

the rise of Christianity, for Constantine was the first

Emperor to equate Christianity completely with the

pagan religion. Interesting for us is that this battle

was a historical event with no archaeological

evidence left. However, there are reports of roman

writers, which allow us to reconstruct the battle site

– stretching from the town of Prima Porta to the

name giving bridge in Rome. Another brilliant

example is the route of the roman triumph, a circle

line through the city; or sites of events, such as the

murder of Julius Caesar, the murder of Tiberius

Gracchus, the site where the ritual declaration of war

took place. Our basic idea is to raise awareness for

such historical sites by marking them with

coordinates and to create a mobile application,

which alerts an interested visitor when reaching such

a site. Consequently, we built on previous work

(Holzinger et al., 2011a), (Holzinger et al., 2011b)

and designed, developed, implemented and tested a

so-called ArchaeoApp Rome Edition (AARE).

According to Marca et al. (2012) e-Business needs

to cope with the behavior and requirements of

“digital natives.” The generation of the digital

natives grew up with the Internet and has a great

degree of competence concerning the usage of

Internet services. Digital natives are well informed

and assertive regarding products they want to buy

1.2 Challenges and Approaches

The implementation of the AARE idea is not trivial

and there are several different approaches for a

solution.

(1) The first challenge is related to information

retrieval: How to bring the historical content to the

mobile device on site. One possibility is that experts

in classics prepare special content and put it on a

Web server, which can be accessed from the mobile

device on demand. The more charming possibility is

to make use of already existing content on

Wikipedia and, since it is an open site, that experts

in classics provide special content in Wikipedia

directly. The challenge is to crawl through the

existing sources and to retrieve relevant data for

display on the mobile device on site.

(2) This brings us immediately to the second

challenge: In commercial mobile telephone

networks, the call setup to an international roaming

subscriber is always routed through the home

network of the subscriber, which results in the usage

of two expensive international telephone trunks.

Apart from some technical solutions (Sardag, 2011),

(Yi-Bing et al., 2011), mostly, the tourists just

disable their Internet access. Our solution is to make

use of existing wireless access points as they are

available mostly in hotels, public places, or

restaurants (e.g. McDonalds).

(3) The third challenge is not less challenging:

Tourists have a variety of mobile devices. Based on

Gartner’s report for the 4

quarter in 2011, there was

an evident Android dominance (50.9%) of the

world-wide smartphone sales. The iOS ranked

second with 23.8% of sales, Symbian third (11.7%)

and Black Berry forth (8.8%). The truth is that

Android is growing faster due to the diversity of

manufacturers.Moreover, the AARE can be adapted

to two different levels: Standard Guiding Modus,

and Scavenger Hunt Play Modus; which brings us to

the fourth challenge.

(4) In our previous work, we made good

experiences with scavenger hunts (Holzinger et al.,

2011b), borrowing powerful concepts from game-

based learning – which, together with mobile

technologies offers enormous potential in the future,

especially from an e-Business perspective

(Bulander, 2010). It can be used for both educational

and play purposes. Essential elements of this play

(timed task, teamwork, mobility) can be used for a

collaborative problem-solving approach; such team

based learning was early recognized as important

(Hutchings et al., 1993): End-users are confronted

with a problem, which is usually more easily solved

by the collective intelligence of the whole group

(Massimi et al., 2007). Collective Intelligence is

currently of high interest among researchers, due to

the fact that there are effects regarding the

performance of individuals on a wide variety of

cognitive tasks (Woolley et al., 2010). Recent

research showed that different collaboration models,

strategies, as well as atmospheres could greatly

influence the performances of its members. In

collaboration, each individual can have better

learning effectiveness (Shih et al., 2010).

2 BACKGROUND

2.1 Milvian Bridge – Historical

Landmark for Christianity

We explain AARE on a first practical example:

Assume you are a historically interested visitor of

Rome. Assume you are just approaching the Milvian

Bridge (Figure 1). AARE automatically detects that

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Figure 1: The Milvian Bridge, as the visitor sees it today

(image taken from Wikipedia: http://en.wikipedia.org/

wiki/Battle_of_the_Milvian_Bridge).

Figure 2: Structured Information to the Battle of the

Milvian Bridge from Wikipedia (see link below Figure 1).

there was a historic event, because it checks

automatically for the coordinates from Wikipedia

(Figure 2) and retrieves it, because the coordinates

have been marked by a qualified historical and/or

archaeological expert as a so-called “invisible site”.

The end user is then reminded by vibration, visual,

or acoustic signal that she/he is in range of an

invisible site. Now the information will be displayed

directly on the smartphone (Figure 2).

The Milvian Bridge is located 41° 56’ 7.8’’ N,

12° 28’ 1.1’’ E.

The battle of the Milvian Bridge was a

significant event in late antiquity, because it was the

event that ended the war between Constantine and

Maxentius. Constantine was victorious, after he had

drawn the Christian symbol Chi Rho on his shields,

as commanded in a vision he had. Although

Constantine himself probably was no Christian, he

sympathized with Christianity and stood at the

beginning of its upraise.

2.2 Theatre of Pompey – The Site of

Caesars Murder

As further nice example for an invisible site we

present the Theatre of Pompey (Claridge, 2010) –

where it is not visible that here Caesar died. In

Figure 3, we clearly see that there is not much to see

today on this classical site. The Theatre of Pompey

is located at 41° 53’ 43’’ N, 12° 28’ 25’’ E.

The eastern end of this first century BC building,

is today located beneath the Via di Torre Argentinia.

In ancient times, there was an annex where Senate

meetings where held, further this is the very site

Julius Caesar was murdered on 15

March 44 BC.

The blue dot in Figure 3 marks the location

Caesars murder took place. It was at the eastern end

of the building, which once contained an annex

where Senate meetings were sometimes held. Today,

it lies under the Via di Torre Argentinia (Figure 4).

2.3 Selected Points of Interest

Here some points of interests as further examples:

 Domus Aurea 41° 53’ 29’’ N, 12° 29’ 43’’ E

This was the private house of Nero, which he

intended to build within the City of Rome. It was

never fully completed, because it was destroyed

shortly after Nero committed suicide. The fact that

this is a type of building not supposed to be built in

the centre of a city is the main cause why the people

of Rome hated Nero.

 Temple of Bellona 41.89’ 24’’N, 12.4799° E

In roman times it was important to justify a war in

front of the gods and declare it a bellum iustum.

ArchaeoApp Rome Edition (AARE): Making Invisible Sites Visible - e-Business Aspects of Historic Knowledge Discovery

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117

Figure 3: The archaeological site: The Theatre and

Porticus of Pompey as described in the Oxford

archaeological guide, the blue spot marking

the murder of Caesar (Claridge, 2010).

Figure 4: The visible site: To the beholder it is not clear

that A was the location of the murder of Caesar (Image

taken from Googlemaps).

For more information on Curia, assassination of Caesar:

http://en.wikipedia.org/wiki/Theatre_of_Pompey.

Very important was the ceremony of war

declaration; the ritual throwing of a wooden spear

across the enemy border to confirm the war. With

the expansion of the Roman Empire one was forced

to create a symbolic enemy territory within the city

of Rome.

 Circus Maximus 41° 53’ 10’’ N, 12° 29’ 9’’ E

It was probably the biggest arena of all times;

although the details on the capacity vary between

300,000 and 500,000 spectators. Throughout its

almost 1000 years of existence the Circus Maximus

was the site of countless historic events, the most

drastic probably would be the great fire of Rome,

which had its origin within one of the shops located

in the Circus.

 Solarium Augusti 41° 54’ 11.38’’ N 12° 28’

42.75’’ E

8This was the largest ancient sundial. It consisted of

a 30 meter high Egyptian Obelisk that Augustus had

erected in 10 BC, at the twentieth anniversary of the

conquest of Egypt. This solar meridian was designed

by the mathematician Facundus Novius. Its purpose

was to demonstrate the accuracy of the new

calendar, which had already been introduced by

Julius Caesar.

 Ara Pacis 41° 54’ 23’’ N, 12° 28’ 32’’ E

This Altar is the most famous example for Augustan

monumental sculpture in Rome. It was decreed by

the Senate on 4 July 13 BC to celebrate Augustus’

return after three years’ absence in Spain and Gaul.

Today the Altar is not at his original location but in a

separate museum. Originally it was on axis with the

great obelisk of Augustus solar meridian.

Very interesting is the Route of Triumph (see

Figure 5), consisting of the following POIs – used of

the AARE Scavenger hunt:

 Campus Martius 41° 53’ 52’’ N, 12° 28’ 38’’ E

 Circus Flaminius 41°53’ 34’’N, 12°28’ 39’’ E

 Forum Boarium 41° 53‘ 20‘‘ N, 12° 28‘ 52‘‘ E

 Circus Maximus 41° 53’ 10’’ N, 12° 29’ 9’’ E

 Forum Romanum 41° 53’ 31’’ N, 12° 29’ 12’’ E

 Kapitol (Rom) 41° 53’ 36’’ N, 12° 28’ 58’’ E

Figure 5: The route of the triumph processing for our

Scavenger hunt game (Image from (MIT, 2012)).

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3 SYSTEM ARCHITECTURE

According to a recent Gartner study

(www.gartner.com/it/page.jsp?id=1622614) Android

will command nearly half of the worldwide

smartphone operating system market by the end

2012. They predict that Apple’s iOS will remain the

second biggest platform worldwide through 2014.

Based on these predictions, we decided on the

Android platform, rather than the one used for the

previous ArcheoApp (Holzinger et al., 2011a),

(Holzinger et al., 2011b). There are two mode types

available in the AARE: tourists and scavenger hunt.

Both types include similar features; the difference is

in how the invisible sites or hints are shown.

3.1 Features Overview

The use of GPS has few disadvantages s.a. potential

failures (battery consumption) and ambiguity

(atmospheric conditions or buildings may prevent

accuracy); however the biggest advantage from the

business perspective is that it works at no cost.

There are two types of modes available in the

AARE as mentioned before:

(a) Standard Guiding Modus and

(b) Scavenger Hunt Play Modus,

both modes include similar features; the difference is

in how the invisible sites or hints are shown.

Table 1: Feature comparison of modes in AARE.

Tourists

Scavenger

Hunt

Map view



My location



All invisible sites



Next hint



Notification channels



Discovery radius



Multilanguage



Help



After the mode type has been selected, a map

view is shown to the user. The map view is based on

the Mapsforge (Mapsforge, 2012) toolbox for fast

on-device rendering of OpenStreetMaps data on the

Android platform. It is released under the free and

open source LGPL3 license.

Users can select their preferable language in the

preference area, which consequently affects the

notification channels (visual & audio). Moreover,

they can set the discovery distance (radius) of

invisible sites. A function for calculating the

discovery radius checks against the data and shows

Figure 6: Use case diagram of AARE application.

dynamically invisible sites on the map view.

In tourists mode users have an option to see

available invisible sites; however this features is

omitted in the Scavenger Hunt where users can

invoke the next hint button instead. The users get an

instructional description by invoking the help button.

3.2 Data Structure

All data (images, content and maps) are stored

externally on the Secure Digital (SD) card.

The descriptors of invisible sites are defined as

XML files and are structured as following:

 id (type: long) – unique identifier

 mode (type: text) – tourists or scavenger hunt

 language (type: text) – language of the text

 description (type: text) – description of the

invisible site

 image (type: text) – name of the image

 latitude (type: ) - latitude coordinate

 longitude (type: numeric) - longitude coordinate

In this way, a higher flexibility for further

releases was ensured (i.e. migrating to different data

storage, size of file system and performance wise).

3.3 Data Updates

A server-side Content Management System (CMS)

for authoring invisible sites is used by authors

(archeologists) who can create, edit, delete and

update invisible sites online.

ArchaeoApp Rome Edition (AARE): Making Invisible Sites Visible - e-Business Aspects of Historic Knowledge Discovery

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On the client-side, an update feature for

retrieving the data from the server-side handles the

synchronization process. When the AARE is

installed on a mobile phone, the update is automatic.

This procedure is shown on Figure 7. First the

AARE sends a request call to the server-side web

address and checks if a new version is available (1).

Next, a compressed package in a zip file format,

containing XML files, images and a map is pulled

down (2). At last the application unpacks the zip

package locally and structures the content

hierarchically (3). The hierarchy is based on folder,

wherein each folder represents an invisible site.

The data update on demand comes very handy

when travelling abroad. It lowers the costs since

users can use free Wi-Fi connections, for example at

a hotel or at public hotspots.

Figure 7: Procedure of data update in AARE.

3.4 User Mode: Tourist

Tourists can discover invisible archeological sites

based on the GPS location. The AARE application

first locates the user over GPS coordinates (gets the

latitude and longitude values from device) and

displays the user's location in a map view as shown

in Figure 8.

However, the invisible sites (presented as red

markers) are not visible immediately. Red markers

on the map become visible when the distance

between the user and the marker is inside the

discovery radius, in our case the default value of the

discovery radius is 500 meters but can be changed in

preferences. When this happens, the user is notified.

Notifications and information delivery can be set

in three ways, depending on the user’s preferences:

(a) Visual - tapping the marker on the map shows

an image with description of an invisible site

(b) Auditory - using the Android speech synthesis.

The Text-to-Speech (TTS) capability notifies

the nearest invisible site and read its description

The notification channels in the AARE represent

a novel approach and reflect similar characteristics

to Visual – Auditory – Kinesthetic – Tactile

(VAKT) learning styles (Boyles & Contadino,

1998). In this way, the users can select their

preferable notification channel according to their

needs for the newly acquired information.

Figure 8: A view on the AARE - blue circle represents the

user’s GPS location, the red pin is the nearest invisible site

which remains inside the discovery radius (500 m).

3.5 User Mode: Scavenger Hunt

The Scavenger Hunt uses the GPS location to unlock

further hints. The idea behind the Scavenger Hunt of

AARE is based on the concept of shade

(Ramachandran, 1988), revealing from the PC game

franchise Heroes of Might and Magic.

The principle of the shading conceptuality can be

seen in Figure 9, used originally in Warcraft I, II &

III, which is the most subscribed online game,

according to a paper from Science (Mayo, 2009).

Such games have potential to dramatically change

how people interact, navigate Web sites, and finally

conduct business (Mennecke et al., 2007), (Petrova

and Qu, 2007) so we took such examples very

serious.

Figure 9: Shading conceptuality (Gamespot, 2002) – there

is now no shading effect in World of Warcraft, since it

uses now a different playing paradigm.

The user in AARE discovers the map based on the

first destination hint. There are no markers visible on

the map at the start when the first hint is revealed

(usually a text-based description but it can also be a

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picture); however when the user starts moving, the

marker (next hint) becomes visible when the user is

inside the discovery radius. The Scavenger Hunt

requires a locked value of the discovery radius and

cannot be changed by the user. This is a security

precaution to prevent cheating.

4 E-BUSINESS ASPECTS

Similar to the ArchaeoApp (Holzinger et al., 2011b)

AARE can bring several benefits:

On a Business-to-Consumer level (B2C) there is

a mass market in tourist areas on a personal level,

where people can download AARE for a small fee.

In March 2012 Google announced the Google Play

digital content service, which represents a unified

marketplace for music, movies, books and

applications. Purchases can be made by using the

Google Wallet system (formerly known as Google

Checkout) for simplifying the payment process.

On a Business-to-Business level (B2B), AARE

can be interesting for a mass market in large towns

with a historic background (e.g. Rome, which is a

good example, due to its 7M+ visitors per year).

However, we emphasize that this might be of equal

interest for smaller towns, open-air museums or

archaeological finding places. A good example is

Carnuntum, formely in the Roman province of

Pannonia (now Lower Austria), where only a few

people know that it contains the largest

Amphitheatre, outside the City of Rome.

It is proven that customer interactions can create

opportunities for positive experiences leading to

long-term relationship building (Rose et al., 2011).

This can be especially relevant for tourism.

Moreover, by using AARE as an attractive

customer benefit, the circle is closed by offering the

big advantage of raising awareness for our cultural

heritage – thus combining both aspects: e-education

and e-business.

5 CONCLUSIONS

We tested AARE on a small scale and it worked

well – real-world demonstration will be given in

Rome. The novelty is in the automatic detection of

an invisible site whilst avoiding roaming costs. The

advantages of AARE are threefold:

First, it represents an automatic invisible site

detection based on Visual-Auditory-Tactile (VAT)

notification channels, where the origins can be found

in Visual-Auditory-Kinaesthetic-Tactile (VAKT)

learning styles. By using all three types of

notification channels (description-speech-vibration),

users have the ability to choose their preferable

channel when receiving the information.

Second, the invisible sites (or hints in scavenger

hunt mode) are revealed inside the discovery radius

by using the shading concept. Based on the user’s

GPS location the discovery radius calculates

dynamically the radial distance to nearest invisible

site and notifies the user if the invisible site has been

discovered. Furthermore, the shading concept gets

especially useful for collaborative problem-solving

assignments in scavenger hunt where users unlock

next hints with their GPS location.

Third, the AARE uses GPS services in

combination with offline maps, avoiding roaming

costs. The users need to update the application

before they travel or by using the wireless network

to get the latest data. In the current version of

AARE, the data are stored in the database manually

using the SQLite Database Browser visual tool,

which is used to administer database files

compatible with SQLite; however this process will

be replaced by a web-based administration. AARE

serves also as a nice example for context awareness

of m-Services, we follow the term context as

originally introduced by (Schilit, Adams & Want,

1994), and the relevance for e-Business described in

(Decker et al., 2006).

REFERENCES

Mayo, M. J. (2009) Video Games: A Route to Large-Scale

STEM Education? Science, 323, 5910, 79-82.

Hoffmann, L. (2009) Learning through games.

Communications of the ACM, 52, 8, 21-22.

Prensky, M. (2001) Digital game-based Learning. New

York, McGraw Hill.

Marca, D., Bulander, R., Kruslin, C., Shishkov, B. and

Sinderen, M. (2012) e-Business challenges and

directions. e-Business and Telecommunications, 3-35.

Harris, E. C. (1979) The laws of archaeological

stratigraphy. World Archaeology, 11, 1, 111-117.

Speidel, M. P. (1986) Maxentius and his Equites-

Singulares in the battle at the Milvian Bridge.

Classical Antiquity, 5, 2, 253-262.

Holzinger, K., Lehner, M., Fassold, M. & Holzinger, A.

(2011a) Ubiquitous Computing for Augmenting the

Learning Experience within an Urban Archaeological

Tour. In: Boerner, W. and Uhlirz, S. (Eds.) 15th Inter-

national Conference on Cultural Heritage and New

Technologies. Vienna, Stadtarchäologie, 348-356.

Holzinger, K., Lehner, M., Fassold, M. and Holzinger, A.

(2011b). Archaeological Scavenger Hunt on mobile

devices: from Education to e-Business: A triple

ArchaeoApp Rome Edition (AARE): Making Invisible Sites Visible - e-Business Aspects of Historic Knowledge Discovery

via Mobile Devices

121

adaptive mobile application for supporting Experts,

Tourists and Children. ICEB-2011, Sevilla,

SciTePress INSTICC, 131-136.

Sardag, A. (2011) A method wherein international

roaming costs are reduced. WO Patent

WO/2011/080637 (7 July 2011).

Yi-Bing, L., Ren-Huang, L., Yuan-Kai, C. and Chai-Hien,

G. (2011) A Handset-Based Solution for Reducing

International Roaming Costs. Wireless Communica-

tions, IEEE Transactions on, 10, 5, 1627-1635.

Bulander, R. (2010) A Conceptual Framework of Serious

Games for Higher Education: A Conceptual

Framework of the Game INNOV8 to Train Students in

Business Process Modelling. ICE-B 2010. Athens,

INSTICC, 1-6.

Hutchings, T., Hyde, M. G., Marca, D. & Cohen, L.

(1993) Process Improvements that lasts - an integrated

training and consulting method. Communications of

the ACM, 36, 10, 105-113.

Massimi, M., Ganoe, C. H. and Carroll, J. M. (2007)

Scavenger hunt: An empirical method for mobile

collaborative problem-solving. IEEE Pervasive

Computing, 6, 1, 81-87.

Woolley, A. W., Chabris, C. F., Pentland, A., Hashmi, N.

and Malone, T. W. (2010) Evidence for a Collective

Intelligence Factor in the Performance of Human

Groups. Science, 330, 6004, 686-688.

Shih, J. L., Shih, B. J., Shih, C. C., Su, H. Y. and Chuang,

C. W. (2010) The influence of collaboration styles to

children's cognitive performance in digital problem-

solving game "William Adventure": A comparative

case study. Computers & Education, 55, 3, 982-993.

Claridge, A. (2010) Rome: An Oxford Archaeological

Guide. Oxford, Oxford University Press.

MIT (2012), Roman Triumph Route. Online available:

http://web.mit.edu/course/21/21h.405/www/ArchesOf

Titus/triumph-route.html, last access: 2012-03-19

Mapsforge (2012), Online available: http://code.

google.com/p/mapsforge/, last access: 2012-03-17

Boyles, N. and Contadino, D. (1998) The learning

differences sourcebook. New York, McGraw Hill.

Ramachandran, V. S. (1988) Perception of shape from

shading. Nature, 331, 6152, 163-166.

Mennecke, B., Roche, E., Bray, D., Konsynski, B., Lester,

J., Rowe, M. and Townsend, A. (2007) Second Life

and other virtual worlds: A roadmap for research.

Communications of the Association for Information

Systems, 22, 20, 37-388.

Petrova, K. and Qu, H. (2007). Playing mobile games:

Consumer perceptions. ICE-B 2007, Barcelona, 209-

214.

Gamespot (2002), Heroes of Might and Magic IV. Online

available: http://www.gamespot.com/heroes-of-might-

and-magic-iv/, last access: 2012-05-10

Rose, S., Hair, N. and Clark, M. (2011) Online Customer

Experience: A Review of the Business-to-Consumer

Online Purchase Context. International Journal of

Management Reviews, 13, 1, 24-39.

Schilit, B., Adams, N. and Want, R. (1994). Context-

aware computing applications. IEEE, 85-90.

Decker, M., Schiefer, G. and Bulander, R. (2006). A SME-

friendly framework for the provision of mobile

services. ICMB '06. International Conference on

Mobile Business, Copenhagen, IEEE, 1-9.

ICE-B 2012 - International Conference on e-Business

122