Ioannis P Chochliouros
email: ichochliouros@oteresearch.gr

Rod Mccall
email: roderick.mccall@uni.lu

Andrei Popleteev
email: andrei.popleteev@uni.lu

Tigran Avanesov
email: tigran.avanesov@uni.lu

Tomas Kamarauskas
email: tomas.kamarauskas@uni.lu

Anastasia S Spiliopoulou
email: aspiliopoul@ote.gr

Evangelos Sfakianakis

Evangelia Georgiadou
email: egeorgiadou@oteresearch.gr

Nikoletta Liakostavrou

Ioannis Kampourakis
email: gkabourakis@ote.gr

Ioannis Stephanakis

Pervasive Gaming Educational and Entertainment Facilities via Interactive Video-to-Video Communication over the Internet, for Museum Exhibits

Keywords: Content management system (CMS), Internet, gamification, "mixed" reality game, pervasive game, video-to-video (v2v) communication

de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

(Semi-) Pervasive Gaming Educational and Entertainment Facilities via Interactive Video-to-Video Communication over the Internet, for Museum Exhibits

Introduction

Information and communication technologies (ICTs) can enable learning and educational activities and help people gain new skills in the modern digital-based economies and societies [START_REF]Education and Information Society: Linking European Policies[END_REF]. Among the core priorities for maximizing the social and economic potential of ICT [START_REF]Communication on Europe 2020: A strategy for smart, sustainable and inclusive growth[END_REF] should be the proper development & the dispersion -as widely as possible-of a variety of modern infrastructures and/or corresponding facili-ties, composing the so called "Future Internet" (FI) [START_REF]Future Internet Assembly (FIA): Position Paper[END_REF]. Thus, the future economy will be a network-based knowledge economy, with the Internet being at its center. This option will be critical to support growth and investments as well as to ensure citizens can access the content and services they want, occasionally via new modes and novel educational or communication means. The aim of the LiveCity ("Live Video-to-Video Supporting Interactive City Infrastructure") Project is to empower the citizens of a city to interact with each other in a more productive, efficient and socially useful way by using high quality video-tovideo (v2v) over the Internet. Video-to-video can be used for a variety of selected activities such as to save patients' lives, improve city administration, reduce fuel costs, reduce carbon footprint, enhance education and improve city experiences for tourists and cultural consumers. To realize its specific targets, LiveCity proposes certain well defined scenarios/use-cases and then it realizes, during its life-time, corresponding pilot actions with the involvement of multiple users. According to the original LiveCity context and conformant to the specific description of its WP4 ("City Cultural & Educational Experiences v2v Pilot"), two specific scenarios will be developed and the inclusion of live (interactive) v2v communication for use in schools and museums will be examined, respectively. In particular, one of the two essential scenarios is the "Museum Exhibit" which proposes the establishment a culturaloriented scenario and it is designed to allow the visitors at two defined locations to interact with one another in a "joint experience"; the related "locations" are the city of Athens (with the participation-involvement of OTE's Telecommunications Museum) and the city of Luxembourg (with the participation/involvement of the Post & Telecoms (P&T) Museum). LiveCity also aims to "promote" awareness of each city to visitors at both locations. The final design will use live interactive v2v as the "basis" for the interaction along with a multi-touch table and perhaps an external display, operated at both museums. Via this modern kind of application, "games" that are to be deployed will allow people playing together in real time, solving a number of puzzles and clues about related topics as well as promoting a variety of educational aspects for various potential categories of users -museum visitors (i.e.: pupils, students, teachers, educators and the public). Focusing upon an interactive v2v communication directly to the public via the LiveCity Project, can be a decisive option for the promotion of OTE's Telecommunications Museum collections to the Hellenic and/or the European public and for the proper and wider dissemination of its programs and/or other related (educational, informative, etc.) initiatives, towards supporting the effort for a more efficient digital cultural and scientific inclusion of local and virtual citizens; this is particularly important for LiveCity as this museum also intends to apply the corresponding facilities to educationally-oriented activities in cooperation with two schools of the Municipality of Vrilissia in Athens, also participating to the Live-City scope. Moreover, similar beneficiary options stand for the P&T Museum in the city of Luxembourg. The proposed activities and the related methodologies will also make all involved people learning more effectively and will support the acquisition of new skills, via the usage of v2v facilities, on a "pure" multimedia-based environment. This will help the effort for ensuring the effective use and exploitation of cultural resources by developing technologies and for making them widely available, usable and re-usable regardless of their form, location, time-sphere, etc. In the scope of LiveCity-based activities, it should be expected that either visitors of the involved museums or other potential users of the proposed innovative solutions may be able to have benefits, directly from the museum content delivery. This will also help to "disperse" cultural and scientific-technological knowledge in a broader multi-mediabased environment and will "trigger" or "challenge" new options for enhancing quality of experience (QoE) for the end-users.

Background

Modern Internet-based facilities have radically modified the way people can communicate, amuse or even make business (in a variety of sectors [START_REF] Amit | Value Creation in eBusiness[END_REF]) and this has become obvious in a variety of v2v platforms supporting such aspects. Digital distribution of cultural and creative content can enable content providers to reach new and larger audiences while this also permits users to enjoy new experiences. According to the actual EU policy [START_REF]Commission of the European Communities: Communication on A Digital Agenda for Europe[END_REF], Europe needs to "push ahead" with the creation, production and distribution (on all platforms) of digital content. Yet to date there is little bringing together of museums, cultural venues or twinned cities by using recent technologies. Within the scope of the LiveCity Project we have promoted the realization of a way of interactive v2v communication between citizens being at "twinned museum" sites, intending to support exchange of information and of experiences; museums can reside in different cities as well as in different European countries. This innovative manner of communication also focuses upon specific cultural and educational aspects with the aim of further enhancing interactivity between all potentially involved users. The challenge becomes greater as, apart from museums, other organizations such as schools, educational institutes or municipal authorities can also "join" the effort at later stages. In order to allow for the exhibit to be used after LiveCity has ended at other locations, a content management system (CMS) is being developed which will allow other venues or cities to "add" their own content to the standard deployed games. We have chosen to "base" the game on the underlying definition of "mixed" reality ([6], [START_REF] Benford | Performing Mixed Reality[END_REF]) which states that a "mixed reality is one where multiple devices allow views and interactions within a given context". This is in contrast to the mixed reality continuum [START_REF] Milgram | A Taxonomy of Mixed Reality Visual Displays[END_REF] which consists of two opposing "poles", real environments and virtual environments with augmented reality and augmented virtuality exisiting in between. Drawing on the first definition, a "game" could consist of mobile devices, fixed screens and tablet computers. Based on this approach we have developed a platform which embraces displays, multi-touch tables and allows the addition of tablet devices. Given the emphasis on supporting collaboration between two remote locations the game is known as "Twin Cities".

The inspiration for our work comes from two previous EC-funded projects, that is: IPerG 1 which developed the "epidemic menace game" and IPCity 2 which developed the mixed reality tent to allow improved participation in the urban redesign process. In the IPerG case, a control room consisting of multiple screens was used where players there could control -or provide-advice to players outside using mobile devices. In our system, there are two connected "control" rooms where visitors at each museum can play together a set of common games. From the IPCity scope we embraced the idea of using an interactive table-top and video display of a remote location and scouting. In the IPCity example, people move objects around on the interactive table and simultaneously these moves are represented on the large screen.

Pervasive Gaming Examples in the LiveCity Context

Pervasive games focus on a game play that is embedded in our physical world. Elements of the physical world are inherent parts of the game. Their characteristics and states are sensed and can influence the course of the game. Moreover, pervasive games allow for a game that can be potentially accessed at any time and from any location. Many of these games rely on mobile and pervasive computing technology, such as cellular phones and location sensors and focus on location-based aspects. The "Twin Cities" game is semi-pervasive in the sense that it extends two of three facets of pervasive gaming ( [START_REF] Montola | Exploring the Edge of the Magic Circle: Defining Pervasive Games[END_REF], [START_REF] Montola | Pervasive Games: Theory and Design[END_REF]), namely social and temporal expansion. For example, unlike traditional computer of board games, the "Twin Cities" lets anyone take part, thus making it a socially expanded game. Indeed, the only restriction on who can play relates to how many people can physically stand round the table, coupled with any legal considerations (e.g., legal age of consent to use such systems). Additionally, the public location of the game means that others can see and even partially participate in the experience. Due to the "shared nature" of the experience (which is to be outlined in the following parts) this lets people assume many roles [START_REF] Montola | Participant Roles in Socially Expanded Games[END_REF], including: (i) Player: someone who influences the game, e.g. someone who directly takes part by using the table ; (ii) Spectator: someone who is aware of the game and can influence it, (e.g. standing around but not directly playing the game); (iii) Bystander: Someone who is unaware of ongoing game, and has no ability to participate. (These could be other museum visitors who walk around the area but do not pay attention to the game).

In addition to the spatial expansion, "Twin Cities" also explores the use of temporal expansion in the context that while individual games can be played, they may take as long as the players wish or indeed be merged into a set of games in which the players collaborate or compete over a period of time -which again is undefined. At the time of writing the present paper, we are exploring how to let players save their scores and retain them for future use. This would allow them to return to the venues many times description of "pervasive games" -a radically new game form that extends gaming experiences out into the physical world. [http://iperg.sics.se/index.php.]. 2 IPCity (FP-2004-IST-4-27571) was an IP EU-funded Sixth Framework program on Interaction and Presence in Urban Environments. Its research aim was to investigate analytical and technological approaches to presence in real life settings. Analytically, this includes extending the approaches to presence accounting for the participative and social constitution of presence, the multiplicity and distribution of events in time and space. More information can be found at: http://www.ipcity.eu/.

and play against other potential users. We intend to explore the concept of "gamification" [START_REF] Deterding | Gamification: Using Game Design Elements in Non-Gaming Contexts[END_REF] where elements such as leader-boards or badges can be used to confer status on people and to encourage them to "remain" within the game. "Presence" is a critical component of the experience within the "Twin Cities" context, intending to allow people from different cultures to get together via a "game-like" environment. In our scope we can consider two main forms of presence [START_REF] Ijsselstein | Being there: The experience of presence in mediated environments[END_REF]: Social presence: The feeling of being with another person.

Physical presence: The feeling of being at another place. The "Twin Cities" framework targets the concept of social presence where the video feed is designed to make people feel like they are together [START_REF] Huizinga | Homo Ludens. A Study of Play Element in Culture[END_REF]. In particular, the emphasis is on improving communication through the use of tangible user interfaces such as the multi-touch table. Prior work in the IPCity context has identified that a shared table approach can be used to foster communication between different people and this encourages negotiation & discussion about relevant topics. Our approach extends this perspective to video communication and to remote locations.

Game Design

This section provides an overview of the selected game designs. Since both involved "parties" are Telecommunications/Post Museums (in Athens and Luxembourg) it would be desirable [START_REF] Salen | Rules of Play. Game Design Fundamentals[END_REF] to combine the following key factors: (i) Take advantage of live v2v infrastructure, where it is possible, to enhance the experience of the games within the participating museums; (ii) consider and promote awareness of the other museum's exhibits-collections, and; (iii) provide general information about telecommunications and/or related technical facilities. In order to perform an effective design and thus to ensure wider applicability-adoptability of the games, the latter have been designed in a way to be "as simple as possible" regarding their perceptive concept without necessitating any specific technical -or other-prior knowledge by the intended users-visitors of the museums. The related concept, per game, has been selected so that to be explicitly relevant to a collection of exhibits and/or to an event-activity promoted by the museum(s). Furthermore, a critical priority of the full game design process was to improve cultural and educational interactivity between users residing in different locations (i.e., cities or countries), in parallel with the inclusion of multiplayer setting so that to have, occasionally, many participating users.

Designing the games ( [START_REF] Piekarski | ARQuake: The Outdoor Augmented Reality Gaming System[END_REF], [START_REF] Björk | Patterns in Game Design[END_REF]) should also take under consideration the factors discussed as follows: 1) For both involved museums we have considered the next classification regarding visitors: a) School groups (i.e.: ages 5-15) cover 90% of visitors (school groups usually consist of teams of 20-35 students); b) Individual children (i.e.: ages 5-10) cover 5%, and; c) Adults (i.e.: ages 35-45) cover the remaining 5% of the visitors' population. 2) Some of the games should mainly address adults in order to "attract" this age group; in this context: a) There should be a co-operation mode between the visitors of the two museums; b) A game should be playable in both groups and by individuals; c) A game should encourage movement and discovery of the related museum's collections. Among the priorities that have influenced the game design process was the inclusion of "multi-player" involvement, although this also depends on other factors like the frequency of visits, any specific events that can attract more people in certain time-slots, etc. In order to overcome this restriction, it would be ideal if the game(s) could be considered as "operational" even in case of the absence of (remote) players ( [START_REF] Preece | Interaction Design: Beyond Human Computer Interaction[END_REF], [START_REF] Popleteev | Touch by Touch: Promoting Cultural Awareness with Multitouch Gaming[END_REF]). This simply implicates that it should be possible, for a museum's visitor to "access" a game being at a certain level of progress or to access a new one. The LiveCity platform supports a v2v-based game concept to fulfill this feature, together with the one of the "distant presence". In addition, appropriate equipment (such as cameras) is to be set-up in the participating museums to extend the proximity area of the multi-touch tables that are to be used for the games. The following sections discuss the selected game designs.

Game Conceptualization

As noted earlier, our work is predominantly focused on providing a degree of social presence between game players, our objective being to use multi-touch interaction and a live video feed between the two locations. Our initial game designs focus on supporting social presence from three main game design perspectives where video is used in different ways to encourage play, discussion and cross-cultural awareness. These are outlined in Table 1 below, with the top level "using video for awareness and communication" being the most basic through "Video as the Game", where the objective is to make the video component the goal. A brief description based on each game is provided in the following section; a more thorough description and additional rationale for the concepts used in some of the games can be found in [START_REF] Popleteev | Touch by Touch: Promoting Cultural Awareness with Multitouch Gaming[END_REF].

Table 1. Use of live video-to-video feeds in games

Level

Example Games Using video for awareness and communication Mosaic, memory and putting things in the right order and quiz and build it together Interacting with video Embedded video in mosaics or memory games Video as the game TV show with live video mixed with CMS content -create a live broadcast

Using Video for Awareness and Communication

These games use video to encourage discussion about the content on each multi-touch table. Rather than the video being the driving factor in the game, video is used passively where players at each location can see and hear the players at the other location while they take part either in local game (one museum only) or multi-player game (two museums playing together). This style of game play was conceived as a way to break down the usual "cultural divide" between twinned locations such as towns or museums where the actual inhabitants or visitors often never meet one another and instead it is on the officials or designated people who get a chance to meet. The approach is also designed to be relatively free form in the sense that while the games should encourage discussion about the content at both museums the visitors are in fact totally free to talk about whatever they wish as there are no content, time or participant restrictions. To a limited extent this allows for a semi-pervasive experience as both players and spectators can take part. Indeed, as the games are ongoing, spectators are free to interact as they wish, perhaps just waving to people or even talking to people at the remote locations. This, in turn, may shape players' behavior.

Fig.1. Mosaic/Jigsaw game example

For this game type content from each museum is placed in a jigsaw or mosaic which is then put into the wrong order (see Fig. 1). Players of the games are then asked to put re-assemble the contents to create the correct image. A more complex version of mosaic based on the "Interacting with Video" level is outlined later.

While mosaic/jigsaw mainly concentrate on visual content play, i.e. they are about reassembling an image the "putting things in the right order" concept operates on both this and the conceptual level. Alternatively, content can be placed in the right order based on conceptual details. For example, at the conceptual level in a telecoms museum, people could be asked to construct a telecoms network across Europe by connecting the correct components such as cables, switches and tele-houses in the right order. Alternative approaches to this include placing things in historical order (see Fig. 2).

Fig.2. Put-in-order game with telephone devices

The classic memory game is familiar to many people and is often played with a deck of cards where people turn over two cards and if they match they keep them facing up. The game is played until all cards have been matched in pairs. This approach is used within our system but with tiles, each tile consisting of a piece of relevant content for example telephones or stamps (see Fig. 3). The memory game can be played either on a visual basis or again on a conceptual one, where people are asked to memorize related concepts when turning over cards.

Quizzes are another popular format and are again applied with LiveCity, in the example (see Fig. 4) (know as "Whose phone is it?") players are asked to match the phone with the right person. In this case, multi-touch is used to drag the images around. While players may be able to guess some of the answers for this, other quizzes' players may also need to spend time finding out about contents in the museum. Additionally, this approach encourages the exchange of information between the two museums as players could be quizzed on content in the other museum. This would necessitate that players find out and discuss content together. The building together game starts by showing the players an image of an object (e.g.: a museum exhibit, art piece, building, or something else), which is then split into several parts which, in turn, are randomly rotated, resized and mixed. The objective is to "build" the original object from its parts. On the first floor of the OTE's Museum in Athens there is a wall-to-wall poster of Alexander Graham Bell, which consists of dozens of the Museum's exhibits and could be easily used for the purposes of this specific game (as shown in Fig. 5). Multi-touch interaction enables an arbitrary number of players to collaborate in the game. Collaboration with the remote players will be facilitated by the live v2v link between game sites. Multi-touch interaction enables an arbitrary number of players to collaborate in the game. Collaboration with the remote players will be facilitated by the live v2v link between game sites. The previous games use the multi-touch table and video feed from a static location in the museum which could result in people being drawn away from the museum content. This problem is not unique to our proposed games and has also been noted in [START_REF] Herbst | Interactive Time Travel with a Mobile Mixed Realty Game[END_REF] where authors suggest that care should be taken to integrate "more closely" real world elements with game content. Therefore, in order to encourage greater exploration of the museum itself, they could be combined with mobile devices so that people must search for information within the museum and take a video or picture in order to complete the game.

Interacting with Video

The majority of the games described in the previous section can also use live video as content. Under this scenario the live video feed becomes embedded to form all -or part-of that particular game. This approach means that players have to physically collaborate on both sides by, for example, remaining still in order for players at the other location so that they can correctly reassemble the mosaic. However, as video is relatively uncontrollable they may adopt other strategies such as using particular movements in order to play a game. These types of games have the potential to increase the level of embodied interaction among players which we hope will, in turn, raise their sense of involvement, engagement and social presence.

In the mosaic game, players at each location could see a live video feed of people from the other location; the video feed is then broken up incorrectly across the mosaic tiles. Under this scenario the players would be confronted with the choice of remaining still at each location -or if they are particularly competitive-perhaps moving around in order to confuse the people at the other location. Such an approach would allow for the exploration of collaborative versus co-operative forms of embodied interaction within such games. Related to this gaming concept is the memory game with a live video feed; under this scenario one of more of the tiles could contain live video from each location which players then have to match. In this setting one tile could represent one feed, or a feed could be spread across many tiles.

Video as the Game

This concept uses the video feed as the objective of the game. The objective of the TV broadcast game is to create an engaging gamified museum browsing experience which encourages visitors to browse more attentively, discover important, interesting or unusual exhibits selected by the exhibition curators, learn about them and share that knowledge via the live video stream with visitors at the other museum. This approach utilizes the v2v platform, multi-touch table and mobile devices. The game functions in the following way: The visitors of the connected museums can browse through the images of the other museums' exhibits by using multi-touch tables. If the visitors of the Museum A (Team A) want to learn more about a particular exhibit they click a "Show it" button. The multi-touch table at the Museum B displays a message that someone from the Museum A wants to see the particular object. The objective of the Museum B visitors (Team B) is to locate and present the object via live video stream by using provided mobile devices with the game application. Once the challenge is accepted the game starts. First, Team B has to locate the object and take the picture of it by using the mobile application. The picture is instantly displayed in the Museum A and its team confirms that the correct exhibit is photographed. Then Team B has up to 5 minutes to learn as much as possible about the object and prepare to present it. Meanwhile, Team A is shown a presentational video or audio guide based presentation about the same object, they can read additional information and see more images of the particular object. When Team B is ready (or when 5 minute time limit is reached), they start the "broadcast" and have up to 2 minutes to present the object through live video. The provided mobile camera-enabled devices -such as tablets-are used to capture the video, by using the game application. When 2 minutes run out the video is stopped, or can be done manually, if the team mentioned everything they wanted. While the presentation is running, people in Museum A see a live video stream and the list of facts about the object on the multi-touch table. If the broadcasting team mentions a certain fact or feature, the viewers have to tap on the button to confirm that the fact was mentioned correctly. Once the broadcast is over, the teams can swap and the presenter can request to present the object from the other museum too. The points are calculated for the least amount of time taken to locate the exhibit, and prepare for the presentation. Facts about the exhibit can have different point weight depending on their complexity (e.g. a player scores 1 point for mentioning that the object is a "light bulb and 5 points for mentioning "Thomas Edison"). Every participating museum can create or accept the challenges and the roles can be switched instantly once the running activity is finished.

Content Management

In order to let other twinned locations create similar experiences, a content management system has been developed which lets other venues use their content within the game templates.

Conclusion

In this paper we have presented a number of games which use video in different ways to promote cross-cultural awareness at twinned locations. Our work was based on the view that video-to-video is largely underutilized within the domain of game playing yet when combined with multi-touch and related forms of intuitive interaction it has a great potential to provide rich experiences. We have expanded upon this by providing three different levels of game which use video-to-video communication in different ways. This classification should provide a useful basis upon which future work can be based. Furthermore, the designs and classifications indicate that at a generic level video to video interaction offers a potential to improve interaction between people and in particular within the proposed cultural contexts.

Fig. 3 . 4 .

 34 Fig.3. Memory game example: stamps Fig.4. The quiz game concept

Fig. 5 .

 5 Fig.5. The Alexander Graham Bell "build together" game concept

IPerG (Integrated Project on Pervasive Gaming) was an EU-funded project (FP6 -004457) which started on 01.09.2004 and came to an end on

29.02.2008. Its aim has been the creation of entirely new game experiences, which are tightly interwoven with our everyday lives through the objects, devices and people that surround us and the places we inhabit. The approach has been through the exploration of several showcase games which come under the

Acknowledgments. The work presented in this paper is from the LiveCity project which is funded by the European Commission under DG CONNECT (FP7-ICT-PSP, Grant Agreement No.297291). Photographs of museum content are from the P&T Post/Musée (Luxembourg) and the OTE's Telecommunications Museum (Athens). We gratefully acknowledge the assistance of the staff from both museums.


Caterina Petrone
email: caterina.petrone@lpl-aix.fr

Francesca Carbone
email: carbonefrancesca@hotmail.itmaud.champagne-lavau@univ-amu.fr.

Maud Champagne-Lavau

Effects of emotional prosody on skin conductance responses in French

Keywords: emotional prosody, tempo, pitch range, Skin Conductance Response, French

This pilot study investigates the effects of emotional prosody in French, as resulting by listeners' electrodermal activity. Differently from responses to standard perception tasks, skin conductance responses (SCRs) are automatic, thus allowing evaluating spontaneous reactions of subjects to external stimuli in a non-invasive way. Based on an identification task on 20 listeners, a set of 4 sentences was selected for the skin conductance study. The sentences were composed of words whose meanings were not emotionally laden. They were uttered with four prosodic patterns each conveying four basic emotions (neutral, joy, anger, sadness). The corpus included 36 stimuli, i.e., 4 natural stimuli and 32 stimuli in which the tempo and pitch range of the whole utterances were independently manipulated. In the skin conductance study, ten listeners rated the arousal and valence of each stimulus a 5points Likert scale. At the same time, SCRs were collected. Results collected so far indicate that: (1) emotional prosody has an effect on the peripheral nervous system activity, even in absence of visual cues (e.g., images, facial expressions); (2) amplitude of SCRs is triggered by auditory stimuli varying both in valence and intensity and (3) SCRs are modulated by manipulation of the prosodic cues.

Introduction

When listening to our interlocutors, we use prosodic information not only for, e.g., parsing the continuous speech stream or recover the most prominent words. Prosodic characteristics of an utterance may also convey speakers' emotional state and listeners can experience an emotional response to them. We refer to this function as "emotional prosody". Emotional prosody might involve changes in listeners' behavior, even in absence of face-to-face interactions. For instance, angry prosody might signal a potential danger for the listener, who might rapidly adapt his behavior to the threatening situation [START_REF] Aue | Peripheral responses to attended and unattended angry prosody: A dichotic listening paradigm[END_REF]. A sad or a happy prosody can lead listeners to experience immediate emotional reactions such as tears. A great deal of work has been carried out so far on prosodic correlates of emotions, such as pitch, intensity, voice quality and speech rate [START_REF] Banse | Acoustic profiles in vocal emotion expression[END_REF][START_REF] Hammerschmid | Acoustical correlates of affective prosody[END_REF] Research has also discussed such prosodic characteristics along two main dimensions organizing emotional responses, i.e., valence (the intrinsic attractiveness or aversiveness of an emotion) and arousal (a state of physiological activation, i.e., how intensely an emotion is felt). For instance, it has been found that prosodic characteristics can be used by listeners to predict whether the speaker is about to give a happy or sad news, even in absence of lexical information [START_REF] Swerts | Prosodic predictors of upcoming positive or negative content in spoken messages[END_REF][START_REF] Rodero | Intonation and emotion: influence of pitch levels and contour type on creating emotions[END_REF]. Based on the level of arousal, researchers have distinguished two main prosodic patterns [START_REF] Pittam | Vocal expression and communication of emotion[END_REF]. The first pattern is characterized by high average of pitch, wide range and variability of pitch, high intensity and high speech rate, is typical of emotions with high arousal, like joy and anger. The second is characterized by low fundamental frequency, range and variability of intonation narrow, weak intensity and reduced speed, is typical of emotions with low arousal, like sadness [START_REF] Scherer | Vocal affect expression: A review and model for future research[END_REF][START_REF] Scherer | Vocal communication of emotion: A review of research paradigms[END_REF][START_REF] Banse | Acoustic profiles in vocal emotion expression[END_REF][START_REF] Swerts | Prosodic predictors of upcoming positive or negative content in spoken messages[END_REF]. It is possible that emotions which have the same level of arousal, share acoustic characteristics like pitch range and speech rate [START_REF] Bachorowski | Vocal expression and perception of emotion[END_REF][START_REF] Scherer | Vocal affect expression: A review and model for future research[END_REF]. In psychophysiological literature, it has been found that emotional arousal of the listeners is typically accompanied by changes at the level of the autonomic nervous system (ANS) such as heart rate, breathing and skin conductance responses (SCRs). In particular, SCRs are abrupt changes in skin conductance as an immediate response to, e.g., external stimuli or events ("phasic SCR"). SCR depends on the activity of sweat glands innervated by the ortosympathetic branch of the ANS. The most frequently used measure of phasic SCRs is amplitude [START_REF] Boucsein | Electrodermal activity[END_REF], which is measured from the baseline (level of skin conductance in absence of any external stimulus) to the peak (maximum value of SCR which takes place after presentation of an external stimulus and during a specified time). Another standard measure of SCRs is latency, which is the period between the stimulus onset and the SCR initiation. The latency window is usually between 1 and 3 seconds. SCRs are a reliable measure of emotional arousal in different domains than prosody, such as the visual domain and music [START_REF] Khalfa | Role of tempo entrainment in psychophysiological differentiation of happy and sad music?[END_REF]. These studies show that SCR amplitude increases with stimulus' arousal and that SCR amplitudes are higher in pleasant/unpleasant stimuli than in neutral ones. However, research on the effects of speakers' emotional prosody is rather scarce [START_REF] Aue | Peripheral responses to attended and unattended angry prosody: A dichotic listening paradigm[END_REF][START_REF] Bernat | Effect of picture content and intensity on affective physiological response[END_REF]. In this study, we explore for the first time the effects of emotional prosody and their prosodic cues on SCRs in French. We focus on the four basic emotions of Power & Dalgleish's model [START_REF] Power | Cognition and Emotion. From Order to Disorder[END_REF], i.e., fear, anger, happiness and sadness (see section 2) as they engage emotional responses varying in both valence (unpleasant vs. pleasant) and arousal (high vs. low). Two experiments were carried out. In an identification task, listeners were asked to identify the emotion conveyed by natural stimuli varying only in their prosodic pattern. The best identified stimuli were used for the second experiment, an EDA study. We hypothesized that SCR amplitude will be higher when listening to angry and happy prosody (as they are associated to emotions with high arousal level) than when listening to sad prosody (as it is associated to an emotion with low arousal level). A secondary aim of this experiment is to explore the contribution of tempo (in terms of speech rate) and pitch range on SCRs. The relevance of these two acoustic parameters is verified by their independent manipulation. We expect higher SCRs amplitude as a reaction to enhancement of both cues.

Methods

The stimuli used in the physiological experiment were selected from a small database of natural utterances produced by two French native speakers. The selection was based on the results of an identification task which was conducted prior to the skin conductance study.

Identification task

This study helped in the selection of the material. Listeners had to identify sentences produced with different emotional prosodic patterns in a forced choice task.

Corpus

The material was recorded in the anechoic room of the Laboratoire Parole et Langage (LPL). Two native female speakers of Southern French, i.e., a phonetician with a long training on prosody (Speaker 1) and a professional actress (Speaker 2) produced 3 sets of utterances composed of words whose meanings were not emotionally laden (e.g., set 1: Amélie a lu la lettre, "Amélie read the letter", set 2: Denise va parler avec lui, "Denise is going to speak with him"; set 3: Vincent va venir ici "Vincent is coming here"). Speakers produced them in a way that they intended to convey 6 emotions by means of prosodic variation (fear, joy, sadness, anger, surprise and neutral state). Sentences uttered with a neutral prosody served as a reference production for each speaker. Utterances conveying surprise were inserted as fillers to balance the number of positive and negative emotions, but they were not considered for the skin conductance study because produced with a different sentence type (incredulity questions). Each target utterance was preceded by an appropriate context aimed at eliciting the 6 emotions on the target sentences. Speakers read silently the contexts and then uttered the target sentences. In total, we collected 36 sentences (3 sets X 2 speakers X 6 emotions).

Procedure

Twenty native speakers of Southern French (10 F and 10 M), aged 20-50 y.o., were recruited for the experiment. They had to decide on the emotion conveyed by the speaker by pressing one of six keyboard buttons corresponding to the list of the six emotions appearing on the computer screen. The auditory stimuli were played from a laptop through the software PERCEVAL [START_REF] André | Perceval: a Computer-Driven System for Experimentation on Auditory and Visual Perception[END_REF]. Each stimulus was heard one times in 3 randomized blocks. The statistical analysis was performed on 720 obs. (20 listeners * 36 sentences). It included a series of logit models with mixed effects, in which the factors EMOTION (6 levels: neutral, happy, angry, sad, afraid), SET (3 levels: set1 "Amélie", set2 "Denise", set3 "Vincent") and SPEAKER (2 levels: speaker1, speaker2) were the fixed factors and LISTENER was the random intercept. Likelihoodratio tests were run comparing full models (e.g., which contained a fixed factor) with simpler ones (e.g., without that factor). This allowed estimating the main effects of the factors. The cutoff for significance is p <.05.

Results

The histograms show the perception of correct identification (y-axis) by the six emotions (x-axis), split by sentence set and speaker. Globally, emotions were relatively well identified both when uttered by Speaker 1 (mean across emotions and sentence sets: 64.4%) and by Speaker 2 (mean: 60.5%). However, there is strong variation in listeners' identification scores for each speaker across emotions and sentence sets. A series of likelihood ratio tests showed that dropping out the factor EMOTION (χ 2 = 212.12, p < .001), SPEAKER (χ 2 = 53.16, p < .001), SET (χ 2 = 172.41, p < .001) as well as their interactions (χ 2 = 149.59, p < .001) led to a significant decrease in model fitting, confirming significant main effects and interactions among the fixed factors. Sentences with neutral prosody were better identified for Speaker 1 (76.6%) than for Speaker 2 (58.3%) across sentence sets. The correct identification of neutral prosody was a crucial criterion to choose utterances by Speaker 1 for the skin conductance study. Indeed, the maximal amplitude of the SCR elicited by the other emotions is expected to be higher in comparison of that elicited by neutral prosody. For Speaker 1, SET 2 (based on the utterance Denise va parler avec lui) was the best identified sentence set. Hence, it was chosen as base for the corpus employed for the skin conductance study experiment. From this set, we discarded the stimulus uttered with fear, since listeners were not able to safely identify the intended emotion. To sum up, we selected 4 utterances from the SET2 and uttered by Speaker 1. These utterances were produced with angry, happy, sad and neutral prosody. The pitch range and duration of these stimuli is illustrated in Table 1.

Skin Conductance Response (SCR)

The goal of this experiment is to determine whether different emotional prosodies trigger SCRs in absence of visual cues. A preliminary analysis of the effects of speech rate and pitch range on peripheral autonomic responses is also offered.

Corpus

The corpus included 36 stimuli, i.e., 4 natural utterances and 32 stimuli in which the tempo and pitch range of the whole utterances were independently manipulated. This low number of stimuli minimized possible habituation effects, which are known to reduce SCRs [START_REF] Braithwaite | A guide for analysing electrodermal activity (EDA) & skin conductance responses (SCRs) for psychological experiments[END_REF]. All manipulations were done by means of Praat [START_REF] Boersma | Praat, a system for doing phonetics by computer[END_REF] In particular, we modified: 1) only tempo (fast, normal, slow); 2) only pitch range (expanded, normal, reduced) 3) and both tempo and pitch range (resulting in four combinations). Stimuli with normal tempo and normal pitch range corresponded to the natural utterances. For tempo manipulations, we first calculated the difference between the natural utterances with the longest (which corresponded to the stimulus with sad prosody) and the shortest duration (which corresponded to the stimulus with angry prosody). This difference is 37 ms. Hence, we got for each utterance a factor to increase tempo by adding 40 ms from the duration of the natural utterances divided by the duration of natural utterances. We then performed the same manipulations to reduce tempo by subtracting 40 ms from the duration of natural utterances divided by the duration of natural utterances.

For pitch, we either increased or decreased the pitch range of each utterance by 3 st. This criterion was chosen for two reasons. First, by trying to applying higher values than 3st, we changed the phonological make up of the sentences, thus resulting in unnatural sounding stimuli. Also, this value is midway between the highest (angry: 11.07 st) and the lowest pitch range (sad: 5.2 st) in the natural utterances.

Procedure

Twenty native speakers of Southern French (16 F and 4 M), aged 20-50 y.o., who did not participate in the identification task, were recruited. They were asked to listen to the stimuli and to rate the arousal and valence of each stimulus on a 5points Likert scale. Values ranged from 1 to 5 (with 1 meaning "very weak" and 5 "very strong" on the arousal scale; and with 1 meaning "very unpleasant" and 5 "very pleasant" on the valence scale). Sound presentation and rating task were accomplished through Eprime 2.0. [START_REF] Schneider | E-Prime User's Guide[END_REF]. At the same time, SCRs were recorded by means of the Biopac MP36R system and Acqknowledge software 4.4 [START_REF] Balconi | Appetitive vs. defensive responses to emotional cues. Autonomic measures and brain oscillation modulation[END_REF]. Evoked SCR were recorded with electrodes on the volar surface of the medial and distal phalanges of the fingers on the non-dominant hand. The experiment was run in a silent room and we asked the listeners to sit in a comfortable chair and to put on professional headphones. A short training session preceded the experiment, in which the listeners had to rate 3 unrelated utterances.

Listeners signed an informed consent form before the experiment.

Results

We report here preliminary results on ten listeners. The analysis of the remaining ten listeners is still in progress. Fig. 2 shows mean values of arousal (x-axis) and valence (y-axis) for the natural utterances, as rated by our listeners. Utterances with angry and happy prosody were rated more intense than utterances with neutral and sad prosody in the scale of arousal.

In contrast, utterances with neutral and sad prosody were judged more pleasant than the one with angry prosody, while happy prosody had the highest score on the valence scale.

Figure 2. Mean values of the rating task for the natural stimuli.

Concerning SCRs, Fig. 3 and Fig. 4 show the amplitude and latency values for the natural stimuli split by emotion. Utterances with angry, happy and sad prosody triggered higher amplitude than the utterance with neutral prosody. The highest amplitude is associated with sad prosody, suggesting that valence plays a major role compared to arousal. Moreover, latency values are lower for angry prosody, meaning that this emotion entails a faster SCR response than the other emotions.

Figures 34. Means and standard error for SCR amplitude (top) and latency (bottom) for the four natural utterances.

The results described so far indicate that listeners have different peripheral responses on emotional prosody, but are these responses modulated by changes in the acoustic parameters of emotional prosody? Although we do not have yet quantitative robust analyses, graphical exploration suggests that SCRs are sensitive to both tempo and pitch range manipulations. These results are illustrated in Fig. 5. At a normal pitch range, we found higher SCR amplitude in stimuli with either fast or slow tempo than in stimuli with normal tempo. The SCR amplitude progressively increases when normal or slow tempo is combined with expanded or reduced pitch, with stimuli characterized by fast tempo and reduced pitch triggering the highest SCR amplitude value. An interaction between tempo and pitch range emerges for utterances with fast tempo, since reduced pitch triggers lower amplitude compared with normal pitch.

Discussion

Concerning the rating task, we found that that angry and happy prosody are rated more intense and less pleasant, while neutral and sad prosody were considered more pleasant but less intense. This is in line with e.g., literature on music perception [START_REF] Amrhein | Modulation of event-related brain potentials during affective picture processing: a complement to startle reflex and skin conductance response?[END_REF]. As for the EDA study, we don't have yet quantitative robust analyses (the results so far are based only on ten listeners) which allow to draw conclusions. However, graphical exploration already suggests that skin conductance responses are sensitive measures of emotions induced by prosody. SCRs were in fact triggered in absence of any other verbal (e.g., emotionally laden words) and non-verbal (e.g., facial expressions) cues. Prosody could induce skin conductance responses depending on the underlying dimensions of emotions, i.e., valence and arousal. Specifically, sad, angry and happy prosody induced higher SCR amplitudes than neutral prosody, which was our baseline condition. The fact that sad and angry prosodies activated higher SCRs than happy prosody is quite surprising, since literature on music perception [e.g., 19], reported that emotions with high arousal level (happiness and anger) have a major impact on SCRs than emotions with low arousal level (sadness). Our preliminary result might be interpreted with respect to the study by Balconi on perception of affective pictures [21], who focused on anger and fear vs. happiness and connected this to "significance they have for the subjects' safeguard". He found higher SCR amplitude for visual stimuli with low valence (unpleasant pictures) than for stimuli with high valence (pleasant pictures) whatever the intensity of the stimuli. Moreover, we found an effect of the manipulation of the acoustic parameters on listeners' electrodermal activity. Speeding/slowing speech rate and expanding/reducing pitch range generally increased the SCR peak. The effect was visible when speech rate and pitch range were presented both as single or combined manipulated cues. Interactions between these two cues are also possible, in that stimuli with fast speech and reduced pitch range showed lower SCR amplitude than the unmanipulated counterparts. Moreover, SCR latency values are lower for angry prosody, meaning that this emotion entails a faster SCR response than the other emotions. Though latency is a standard measure of SCRs, few studies have investigated the changes of SCR latency in relation to emotional dimensions. [START_REF] Amrhein | Modulation of event-related brain potentials during affective picture processing: a complement to startle reflex and skin conductance response?[END_REF] found that there are no differences in SCR latencies when listeners are exposed to visual stimuli varying in valence, such as pleasant vs. unpleasant images. As far as we know, there are no studies on SCR latency in connection with arousal. There are at least two possible explanations to our results. First, anger is the negative emotion with the highest arousal. From both a phylogenetic and ontogenetic standpoint, angry prosody is of primary importance because it might signal a potential danger for the listeners. Listeners' rapid physiological adaptation is required to support rapid action preparation for the purpose of their own safeguard. Hence, it is possible that stimuli with angry prosody captured the highest degree of attention by the listeners. This might be independent of the involvement of voluntary processes, since SCRs are automatic. A second hypothesis concerns the phonetic and phonological aspects of the stimuli. It might be possible that stimuli uttered with angry prosody contained salient acoustic changes in pitch/rhythm (such as high pitch excursions or modulations in the durational patterns) or specific intonation contours (in terms, e.g., of number and type of pitch accents). Thus intrinsic prosodic properties might have drawn listeners' attention to stimuli with angry prosody compared to the other stimuli. Future experiments might help in deciding among these two hypotheses. For instance, the first hypothesis could be addressed by comparing different auditory stimuli signaling emotions with same arousal and valence as anger, such as fear. We should expect in fact similar SCRs latencies in both emotions. The second hypothesis might be addressed through a study in which the prosodic contour is more strictly controlled and acoustic variations in the signal are statistically correlated with SCRs. It is supposed that salient acoustic variations should affect SCR latency independent of the type of emotion. Finally, we would like to point out that this study has shown for the first time the effects of different emotional prosodies and prosodic cues on peripheral autonomic system. Hence, we suggest that skin conductance responses are a valid methodology to investigate psychophysiological effects of emotional prosody. Differently from verbal activity, electrodermal activity is automatic, which allows evaluating listeners' spontaneous reactions to external stimuli in absence of voluntary processes. Moreover, this technique is noninvasive which is another possible advantage compared to methods which directly evaluate brain activity. Hence, it might be easily applied to larger samples of subjects and across different populations, e.g., to study the effects of emotional prosody on patients with disorders of emotional experience.

Figure 1 .

 1 Figure 1. Participant's responses for utterances produced by speaker1 (top) and speaker2 (bottom), split by sentence set and emotion.

Figure 5 .

 5 Figure 5. Means and standard error for SCR amplitude (top) and latency (down) split by tempo (top) and pitch (down) manipulations. Data are collapsed across emotions.

Table 1 :

 1 Prosodic correlates of sentence "Denise va parler avec lui" uttered by phonetician.

	Emotion F0 range (st) Sentence duration (ms)
	tristesse	5.2	155
	neutre	10.7	143
	Joie	10.6	145
	colère	11. 07	118

Acknowledgements

We thank Daniel Hirst for technical help with Praat. This study is also supported by a grant of the Agence Nationale de la Recherche (ANR 107923) to the first author and by an Erasmus Placement grant for mobility offered by Pr. F.M. Dovetto (University of Naples) to the second author.


Perrine Pittet
email: ppittet@articque.com

Jérôme Barthélémy
email: jbarthelemy@articque.com

Experience of Formal Application Ontology Development to Enhance User Understanding in a Geo Business Intelligence SaaS Platform

Keywords: Cartes & Données, application ontology, ontology development, ontology evaluation, semantic annotation, geo business intelligence

This paper intends to share the development experience of the application ontology of the SaaS version of the decision statistical mapping and geomarketing software Cartes & Données (C & D). The ontology describing the C & D application domain was conceived for automation of semantic annotation of CD7Online's users data to help users better understand their data and make better selection and representation choices. We followed the application ontology development methodology of Noy and McGuinness, which we expanded with the mapping to an upper ontology and an additional ontology evaluation step according to user specific needs.

Introduction

Cartes & Données1 (C & D) is a decision statistical mapping and geomarketing software published by Articque2 that allows common users to obtain effective and interoperable maps, without being mapping specialists. As a business decision tool, it is a data analysis and visualization oriented application, which aims at helping people to take decisions via the maps they build upon the analysis of their geo-statistical data. Taking advantage of the new development cycle of the software-as-a-service (SaaS) version of C & D, i.e. CD7Online, Articque decided to improve users experience to help them build meaningful maps. CD7Online is self-served, and as such needs to be self explanatory, simple, clean and highly intuitive for users. This is one of the key points to its success and it concerns both Web application ergonomics, features and data levels. To improve user experience, a recent trend, in SaaS projects, is to increase user friendliness by building user profiles and adapting application interface and services to the users preferences and context [START_REF] Tsai | Oic: Ontology-based intelligent customization framework for SaaS[END_REF]. These advances have already been implemented in CD7Online, which embeds new user based features, personalized access, notably to manage user roles and rights policies, and suitable ergonomics.

However, although user profiling and ergonomics allow the user to better customize the interface of the platform and facilitate their navigation, they are not enough to help them better understand their data and better assimilate the business processes of CD7Online. Actually, to compute pertinent results, CD7Online relies on the users good knowledge of their data and their ability to choose the relevant analysis and representation tools to build relevant maps. Data understanding is therefore a critical point for the success of CD7Online. Foster human understanding regarding data on the Web is the main goal of the Semantic Web [START_REF] Berners-Lee | Semantic Web Stack[END_REF]. To achieve this, knowledge must be extracted from data or be added thereto using a formal explicit terminology, i.e. an ontology, shared by all the users of the considered information system. Today ontologies are considered as the backbone of Semantic Web because they bridge the semantic heterogeneity gap. Therefore, to solve the data understanding issue, we decided to integrate a semantic layer to CD7Online platform to extract and represent knowledge of CD7Online user data. One of the main features of this layer is to show the users the concepts related to their data and their semantic relations, and to allow them to intuitively navigate, compare and select compatible data to build relevant maps. Domain ontologies knowledge may however not be enough complete to describe these application specificities, because that knowledge strongly depends on the CD7Online platform specific uses and processes. This implies the development of a specific application ontology.

Within this context, this paper intends to share the development experience of formal application ontology in the industrial context of the C & D SaaS version commercial development and release. The rest of this paper is articulated in 3 sections. The second section describes the background of the CD7Online project, the reasons for the development of a formal application ontology and the criteria to take into account. The third section describes the development process within the CD7Online project and exposes the choices made at each step. The fourth section presents an analysis of the successes and drawbacks of this development experience regarding the industrial context of the project, and attempts to identify good practices for future projects.

Background

This section presents the background of the CD7Online project, such as the editor choices, the reasons of the introduction of a semantic layer and the criteria to take into account for the development of the associated ontology.

From C & D to CD7Online

C & D was first released more than 20 years ago with the main objective to make it very easy for cartographers and practitioners to build maps using their descriptive statistics data and base maps. For this purpose, a tool for building maps was implemented, in the form of a visual programming language. It enables graphically building an equivalent of the mental process used by cartographers. In the domain of mapping software, the idea was innovative in terms of ergonomics, and was already adopted in the domain of audio processing (Max/MSP3 ). The description of the tool is not the purpose of this paper. We just underline this concept has proven itself on this problem. Two years ago, in 2013, a survey was conducted with a significant panel of users of the software. For about 50% of users, the ease of use and ergonomics of the solution was the main reason for the choice of the software tool. Therefore, the ergonomics and the ease of use of the solution is not just an implementation detail for Articque, as a software publisher. It is one of the main design principles of this software tool, and even the most important one. However, the efforts done to develop ergonomics did not resolve the problem of data identification and compatibility, which solely relies on the user's knowledge. To bridge this gap, the C & D development team designed an online version of the C & D software tool, called CD7Online, with the idea of easing the understanding and access of the users workspace. To achieve this, a semantic layer supported by an ontology-based semantic annotation was designed to extract and represent the user data knowledge, as such as the application uses and processes, via metadata. The introduction of this layer aims at encouraging CD7Online users to improve their maps by guiding them to use the right descriptive statistics data with the correct base maps, choose the right analysis tools and the best representations -for instance, by providing suggestions of base maps or data relevant to the user map project. On the social and strategic aspects, the domain terminology homogenization can help CD7Online users to better understand each other when working on the same map project. Additionally these maps' semantic annotations, which are used to identify the semantic relations between maps, allow reinforcing the user community by suggesting working groups to users having published closely related maps.

Semantic Annotation in CD7Online and Application Ontology

Automatized semantic annotation of data is the process of automatically associating relevant metadata to data, so that each data is described by a set of semantic annotations. According to [START_REF] Kiryakov | Semantic annotation, indexing, and retrieval[END_REF], a practical semantic annotation is impossible without some particular knowledge modelling commitments. i.e. an ontology. They add that a system for semantic annotation should be complemented with extensive instance knowledge. In our case, the knowledge model must describe all the metadata used to annotate the C & D user data and the extension must contain all the corresponding instances. For example, GeographicalLevel is a metadata describing the geographical division level used by a map. Its definition, including semantic relations and logical rules, is stated by the knowledge model. Its instances, such as regional level, department level or city level, are used to annotate user data files, w.r.t. this definition. Also, in order to help users understand their data annotations, corresponding terms have to describe the application domain, uses and processes in an explicit and consensual way, so that they can be shared and used by all the users of the application. The definition of a formal application ontology as such knowledge model definitely suits this requirement. According to [START_REF] Malone | Reference and application ontologies[END_REF] an application ontology is an ontology engineered for a specific use or application focus and whose scope is specified through testable use cases.

For the purpose of this article, we rely on the ontology definition of [START_REF] Gruber | A translation approach to portable ontology specifications[END_REF]. Therefore, we define the application ontology as a formal explicit description of concepts of the C & D user data domain, properties of each concept describing various features and attributes of the concepts, and restrictions on properties. The ontology together with the set of individual instances constitutes the knowledge base designed for the automatized semantic annotation process. For example, a concept of DataIndicator represents all the data indicators, which can qualify descriptive statistics data of a user data storage. We can specify specific indicators as instances of this concept. For example, « rate » is an instance of the concept DataIndicator. A concept can have subconcepts representing concepts that are more specific than this concept. For example we can specialize the concept of UserData, into the subconcepts StatisticalData, GeographicalData and Maps. Properties describe properties of concepts and instances. For example, we can describe instances of StatisticalData as composed of DataColumn instances, which have a title, and are related to a DataIndicator instance. Here we have three properties: the column property describing a StatisticalData instance with an instance of DataColumn, the title and the dataIndicator properties describing a DataColumn instance with the respective values: a literal value and an instance of DataIndicator. For example, we can specify the instance ventes2014 of StatisticalData as a data file composed of three columns, which have for titles « City code», « Nb Inhabitants » and « Sales », and respectively have for related data indicators the instances city_code, population and turnover. We chose to specify the ontology in OWL DL language to keep the maximum expressiveness possible while retaining computational completeness, decidability and the availability of practical reasoning algorithms.

Ontology Development Methodology

Many methodologies have been proposed in the literature to help ontology developers as described in [START_REF] Corcho | Methodologies, tools and languages for building ontologies. Where is their meeting point?[END_REF], [START_REF] Subhashini | A survey on ontology construction methodologies[END_REF], and [START_REF] Suarez-Figueroa | The NeOn methodology for ontology engineering[END_REF]. Globally, besides the identification of some key development steps, ontology development appears to be a creative, iterative and collaborative process, which implies the participation of different people with different points of view on the domain to describe. Therefore the potential applications of the ontology and the designers' understanding and view of the domain undoubtedly affects ontology design choices. According to [START_REF] Noy | Ontology development 101: A guide to creating your first ontology[END_REF], in practical terms, developing an ontology includes: defining concepts in the ontology, arranging the concepts in a taxonomic hierarchy, defining properties and describing allowed values for these properties, and filling in the values for properties for instances. Then a knowledge base, defining individual instances of these classes filling in specific properties value information and additional property restrictions, can be created. Ontology correction and evolution is often required to adjust the terminological description to undetected or new requirements especially in the case of application ontologies. Also the choice of a specific ontology development methodology depends on the possible uses of the ontology (semantic heterogeneity resolution, domains fusion, inference, etc.), the level of detail (general, domain or application level) that is necessary for the application, personal preferences, and sometimes requirements for compatibility with other models (ontology integration).

Ontology Development Process

For CD7Online semantic annotation purpose, we chose to follow a simple knowledge engineering methodology proposed by Noy and McGuinness [START_REF] Noy | Ontology development 101: A guide to creating your first ontology[END_REF], dedicated to the development of application ontologies. The 7 steps of this methodology are described and illustrated through the presentation of the CD7Online application ontology development process in the following parts.

Determination of the domain and scope of the ontology

This step aims at determining the domain and scope of the ontology by answering the following questions: [START_REF] Tsai | Oic: Ontology-based intelligent customization framework for SaaS[END_REF] what is the domain the ontology will cover? [START_REF] Berners-Lee | Semantic Web Stack[END_REF] For what are we going to use the ontology? ( 3) For what types of questions the information's in the ontology should provide answers? (4) Who will use and maintain the ontology? For this first step, a pre-analysis of the domain was realized in partnership with the C & D domain experts: C & D development, product support, training, business, geomarketing, and cartography teams. This pre-analysis of the domain consisted in interviews with members of each team about its expert subdomain to delimit the domain the ontology will describe. We managed to gather many user feedbacks, which helped us to precise the applications of the ontology and therefore guide the ontology conception choices. We then answered the questions above: (1) the ontology will describe the CD7Online user data including descriptive statistics data files (tables of data), geographical data files (base maps) and maps projects (organization charts), but also the platform related business processes and uses; (2) this ontology will be used as a model for the automatized semantic annotation of the user data; (3) it should provide answers to the following questions: What do users data represent (in terms of the domain concepts)? What do they contain? How are they linked? What is their type? How are they used? What is their scope? How can these data be used?; (4) this ontology will be used by the CD7 online version of the C & D software tool for the automatized annotation of user data and recommendation of semantically related data, projects, groups. CD7Online users will only interact with the semantic annotations and recommendations. The ontology will be maintained by the application developers and supported by the application domain experts.

Consideration of the reuse of existing ontologies

We extended this second step of considering reuse of existing ontologies to searching out various representative dictionaries related to the domain of interest as recommended by [START_REF] Little | A Proposed Methodology for the Development of Application-Based Formal Ontologies[END_REF]. We identified two means of finding those relevant resources.

First we searched domain ontologies, embedding dictionaries with strong formal semantics, which have been developed with the goal of being reused by users of the domain they describe for their application needs. The domain to be covered by the C & D application ontology includes the definitions and relations between descriptive statistics data, geographical data (base maps), map projects and their usages within C & D. To cover this domain, we selected: indicators from the general statistics ontology STATO 4 , quantities, units, and dimensions from QUDT 5 ontology, geographical properties from GeoNames6 , and concepts of map representation and symbolization process from cartographic ontologies as presented in [START_REF] Iosifescu-Enescu | Towards cartographic ontologies or" how computers learn cartography[END_REF]. Second, we searched the CD7Online development project environment resources. With the help of the C & D development and cartography teams, we actually found knowledge models of public descriptive statistics data indicators and geographical data (base maps). Descriptive statistics data indicators are classified and available in the MapAndData7 frontend database. Their classification takes into account the geographic spaces, the geographic levels, the data projection, and the related themes.

The MapAndData database administrators have also built a dictionary of the corresponding data indicators for each theme and manually annotated them with the right data type, units and geographical levels. This dictionary of metadata on the public data contains the basic vocabulary and describes the basic relationships between metadata. User personal descriptive statistics data are expected to meet the same data indicators and themes if used in conjunction with these public data. Analysis of maps files created by C & D users, allowed extracting their structure, which is specific to C & D. A map contain an organization chart, which is a graph representing the modules used to bind data to base maps, process them and render them within a 2D visualization. Also, searching the C & D specifications, we found that all maps components and rules are already defined. Once relevant domain ontologies and resource models are identified, we manually sift through those dictionaries in order to extrapolate all of the relevant terms for that domain. We obtained a rough-draft, resource lexicon like recommended by Guarino [START_REF] Guarino | Formal ontology, conceptual analysis and knowledge representation[END_REF], which is a blend of other disparate sources of information.

Lexicon of important terms in the ontology

The third step consists in building a rough lexicon of important terms related to the domain. We chose to identify these terms by defining the application domain data and processes in natural language. In the following description, these terms are written in italic. As stated before, the application ontology focuses on the description of C & D user data. [START_REF] Little | A Proposed Methodology for the Development of Application-Based Formal Ontologies[END_REF], once the rough-draft lexicon was compiled, each term in that lexicon was examined in order to uncover merged or composite terms, whose definitions contain secondary terms which themselves require definition.

Definition of the concepts and concept hierarchy

Once the lexicon of terms is considered complete and consistent, we followed the recommendations of Little and Engineer [START_REF] Little | A Proposed Methodology for the Development of Application-Based Formal Ontologies[END_REF] and selected a set of inter-related upperlevel categories from the foundational ontology DOLCE [START_REF] Masolo | WonderWeb Deliverable D17. The WonderWeb Library of Foundational Ontologies Preliminary Report[END_REF]. This part of the ontology development process was not only a mapping exercise to this upper ontology. It provided the C & D ontology an abstract, philosophical basis, which is crucial for its design, implementation and reuse and under which every specific category within the ontology falls. Although the C & D ontology is not meant to be reused for the moment, we do not foreclose this eventuality in the future. We also believe this metaphysical foundation may ease the potential integration of other formal ontologies. We chose the DOLCE foundational ontology [START_REF] Masolo | WonderWeb Deliverable D17. The WonderWeb Library of Foundational Ontologies Preliminary Report[END_REF] (cf. Fig. 1) because it is a solid starting point for building new formal ontologies. The mapping consisted in three steps. We first identified the most general concepts among our list of terms: User and Component. Second, we defined them precisely: A User is a person who has a user account on the CD7Online platform; a Component is a component of any type, which can be related either to user data (DataComponent) either to the CD7Online specific application processes (CDComponent). Third we determined the categories under which they fall. User and Component are Endurant according to the DOLCE upper level categories because they are independent essential wholes. They are Non-physical object as they have no direct spatial qualities (no weight, etc.).They are both Social object as they are entities from the social world. Social object includes both agentive and non-agentive socially constructed objects.

User can be categorized as an Agentive social-object and more precisely as a Social Agent as a user is assumed to have intensions, beliefs and desires. Inversely, Component is a Non-agentive social object and more precisely as an Information object it can be realized by some entity, ordered by some system for information encoding. It can express a description, can be about any entity, and can be interpreted by an agent. Once the upper-level taxonomy in place, the domain and application-specific categories were derived from the ontology's lexicon. However, many of the domainspecific categories needed for the ontology were not exhaustedly defined by the set of terms within the lexicon. Many terms' definitions contain subsequent terms within them, which also needed to be categorized within the ontology. For instance, Statistical data is defined as user data, which have at least one id column and one data column. Below is the corresponding description logic definition [START_REF] Baader | Basic description logics[END_REF]:

StatisticalData ≡ UserData ⊓ ≥1 hasColumn.DataColumn ⊓ ≥1 hasIdColumn.DataColumn
This definition implies to define the UserData and DataColumn concepts. User data are data files owned by a user with a filename expressed as a string, and they can have a geographical level and/or a geographical space. Here is the corresponding definition:

UserData ≡ File ⊓ ≥1 ownedByUser.User ⊓ 1 filename.xsd:String UserData ⊑ 1 hasGeoLevel.GeographicLevel UserData ⊑ 1 hasGeoSpace.GeographicSpace
These definitions lead us to define the terms File, GeographicLevel and GeographicSpace, etc. All the terms' definitions describe a hierarchy of terms extending the upper-level categories hierarchy (cf. Fig. 1). For instance the following definition of Metadata, which are information of user data obviously specified or semantically extracted from UserData.

Metadata ⊑ DataComponent Metadata ≡ ColumnTitle ⊔ DataType ⊔ DataIndicator ⊔ Theme ⊔ Date ⊓ GeographicalLevel ⊔ GeographicalSpace ⊔ Unit
This definition implies an underlying concept hierarchy, represented in Fig. 2 below.

Properties Definitions and facets

Once the whole concept hierarchy was established, the properties domain and ranges, and their facets could be defined. For instance the ownedByUser property is an object property, which describes a relation of ownership between a file (domain) and a user (range). According to the notations used in [START_REF] Zhang | Using description logics in relation based access control[END_REF], the domain and range of the ownedByUser property are defined below:

∃ownedByUser.T ⊑ File ∃ownedByUser -.T ⊑ User Among the facets to define, the property cardinalities restrict the number of range or domain instances a property can respectively have for a same instance in the domain or a same instance in the range. For example, the ownedByUser property was restricted by:

File ⊑ ≥1 ownedByUser.User File ⊑ ≤n ownedByUser.User User ⊑ ≥0 ownedByUser -.File User ⊑ ≤n ownedByUser -.File

Creation of Instances

After defining the terminology, the remaining step was to create the required individual instances of concepts in the hierarchy to setup the knowledge base for our needs. Instances of the concepts WeightedWord, WeightedTerm, DataIndicator, Datatype, Themes, Units, GeographicalLevel, GeographicalSpace were required for the automatized semantic annotation process. For example, to identify and annotate a data column with a data indicator and a theme, the process evaluates the similarity of data cells content with weighted words, which are composed of weighted terms associated to data indicators, themselves classified in themes. Instances of all these concepts were stated according to the MapAndData database compilation. In addition to the ontology development steps listed by [START_REF] Noy | Ontology development 101: A guide to creating your first ontology[END_REF], we added another step that we believed important for our purposes: ontology evaluation.

Ontology Evaluation

As stated in [START_REF] Little | A Proposed Methodology for the Development of Application-Based Formal Ontologies[END_REF], ontology evaluation represents the most difficult step because it amounts to an elaborate feedback mechanism, nearly identical to the form of feedback found within life-cycle models in other areas of systems engineering. Subhashini and Akilandeswari [START_REF] Subhashini | A survey on ontology construction methodologies[END_REF] recommend evaluating the constructed ontology by taking some evaluation criteria. These criteria can be categorized into two types, namely generic criteria and specific criteria. The generic criteria deal with factors like clarity, consistency, and reusability. The specific criteria check the generated ontology against the purpose and user requirements. Concerning clarity, it has been assessed by the C & D teams members. Consistency was evaluated by the Pellet reasoner. Reusability was not measured as, for the moment, the ontology is only designed for C & D application semantic annotation purposes. To assess the ontology against specific criteria, we needed to deploy the ontology on an environment similar to the production one in order to test it on real data. As we said, ontology development is an incremental process, during which the ontology is refined until its condition allows it to achieve the purpose for which it was developed. Refining the ontology actually tended to increase the number of axioms and therefore the size of the ontology. Therefore, we had to load the ontology in a triplestore instead of loading the ontology in memory each time it has to be queried. We chose the Fuseki triplestore because of its compatibility and ease of use with both Java and PHP technologies, which are implemented in CD7Online. Within this environment several real case sets of data, base maps and maps have been tested after each semantic annotation process by assessing the annotations correctness and consistency such as data type, statistical indicator, unit, year, geographic level and geographic area. For instance the percentage of good annotation of data with statistical indicators obtained at the first evaluation round on a set of 571 data columns was 35.2 %. 38.4% data columns were not annotated because no indicator was identified or the system could not choose between several ones. 17.7% annotations were non-optimized and 8.8% wrong, because certain indicators were not modelled or too specific. The ontology was revised to obtain better results and we have fixed an objective of 80% good results. Also, regarding the business inherent necessity to obtain quick results within short deadlines, the ontology revision process had to be stopped and restarted several times to keep pace with the development runs. The last revision permitted to reach 82.5% of good annotations. Tests are not finished yet; the application ontology is integrated into a beta version of the CD7Online application, which is still tested by a limited set of users.

Conclusions and future works

In this paper, we first presented the CD7Online project and explained why it needs a semantic layer to help its users better understand their data and the platform features. We also justified the development of an application ontology to support the automated semantic annotation of the CD7Online user data. Second we presented the different phases of the application ontology development following the application ontology development methodology of Noy and McGuiness [9]. This experience exposed several issues concerning the development of a formal ontology in an industrial project, namely the lack of time. Ontology development is a collaborative labour-intensive manual task, which requires a meticulous analysis phase, comprising the study of various representative dictionaries related to the domain of interest, and a conceptual modelling phase with many refinement stages to increase the ontology soundness and completeness. We try to meet these requirements, in the context of the CD7Online product release, through the allocation of a full time resource on this task for several months. To improve and facilitate the evaluation of this ontology, we would recommend a specific benchmark embedding a corpus of diversified descriptive statistics data, base maps and maps dedicated to C & D software tool, and a list of evaluation criteria such as annotation correctness and consistency average, precision, scalability. Today CD7Online provides users with an interactive visualization tool designed for intuitively navigate through data via metadata, built on the top of the semantic layer. Beyond this first application, we envision in the future the development of a recommendation tool, aiming at sharing good practices, data or base maps, or working groups, the main idea being to make easier and more efficient the use of the CD7Online software tool.

Fig. 1 .

 1 Fig. 1. Upper level categories of CD7Online ontology reusing DOLCE

Fig. 2 .

 2 Fig. 2. Underlying concept hierarchy of Metadata

  Three types of user data are considered for semantic annotation: descriptive statistics data, geographical data and maps. The definition of the term user data required delving into other subordinate definitions such as user, data, statistical data, geographical data etc. Understanding the term user data therefore depends on understanding these related terms. Statistical data also called data tables are both public and user private statistics, which are owned by the users and stored on their data repository. These tables are composed of columns of data with at least one id column. Each column has a title and corresponding type and data indicator. A column can have a date but also a unit if its type is numeric. The id column name is a geographical code data indicator, which indicates the geographical level considered by the whole table data. Data results and column titles are obviously recognizable in tables whereas the extraction of other information requires a natural language processing extraction approach to be applied. We have chosen a structural data semantic annotation methodology, like proposed by[START_REF] Hignette | Annotation sémantique floue de tableaux guidée par une ontologie[END_REF] using semantic similarity rules, to decompose each table cell content into French lemmas, and compare them with weighted words, composing weighted terms used in the domain, and associated to data indicators. Geographical data also called base maps are also owned by the users and are used to represent descriptive statistics data results on a geographical map. They are specified in a proprietary format, which can only be processed by C &

D. Therefore their corresponding date, geographical space and level cannot be extracted from their content, but appears in their filename. Maps also called C & D projects are the result maps of the representation of statistical computations on base maps. Maps contain an organization chart composed of relations between modules. These relations enable binding statistical and geographical data with calculation, statistical and geographical operators and representations. A module takes a statistical or geographical data as input and display calculated descriptive statistics data, representations or visualizations in output. Modules are classified in C & D according to their use purpose (data sources, geographical, statistical and hybrid data operators, representations and visualizations). According to Little and Engineer

  Defining an individual instance of a concept requires (1) choosing a concept, (2) creating an individual instance of that concept, and (3) filling in the properties values. Below is an example of instances creation to setup the rate indicator for semantic annotation:

	WeightedWord(w_mortality0.2)
	WeightedWord(w_rate1.0)
	weight(w_mortality0.2, 0.2)
	weight(w_rate1.0, 1.0)
	text(w_mortality0.2, « mortality »)
	text(w_rate1.0, « rate »)
	WeightedTerm(t_mortality_rate)
	hasWeightedWord(t_mortality_rate, w_mortality0.2)
	hasWeightedWord(t_mortality_rate, w_rate1.0)
	DataIndicator(rate)
	associatedWeightedTerm(rate, t_mortality_rate)

http://www.articque.com/solutions/cartes-et-donnees/

http://www.articque.com/

http://en.wikipedia.org/wiki/Max_(software)

http://stato-ontology.org/

http://www.qudt.org/

http://www.geonames.org/ontology/documentation.html

http://www.mapanddata.com/