Joel E Fischer
email: joel.fischer@nottingham.ac.uk

Wenchao Jiang

Stuart Moran
email: stuart.moran@nottingham.ac.uk

AtomicOrchid: a Mixed Reality Game to Investigate Coordination in Disaster Response

In this paper, we draw on serious mixed reality games as an approach to explore and design for coordination in disaster response scenarios. We introduce AtomicOrchid, a real-time location-based game to explore coordination and agile teaming under temporal and spatial constraints according to our approach. We outline the research plan to study the various interactional arrangements in which human responders can be supported by agents in disaster response scenarios in the future.

Introduction

Disaster response (DR) typically include groups of human, canine, computational and embodied agents (such as robots) coordinating a response to a disaster such as an earthquake, a flood, a terrorist attack, an epidemic outbreak or a nuclear disaster. Responders may have to coordinate and perform their operations potentially under critical temporal and spatial constraints, with limited resources and personnel, where failure may cost human lives. Particularly, coordination is an essential requirement in DR in order that groups of people can carry out interdependent activities together in a timely and satisfactory manner [START_REF] Bradshaw | Human-Agent interaction[END_REF].

The ORCHID project 1 investigates the potential of human-agent collectives (HACs) in a DR scenario, where groups of humans and computational or embodied agents collaborate to achieve a common task. The critical nature of the DR domain makes it difficult to evaluate and study systems designed to support or enable HACs 'in the wild'. On the other hand, computational simulations of such scenarios are not only extremely difficult to construct, but the veracity of results may be impossible to verify [START_REF] Simonovic | Systems Approach to Management of Disasters: Methods and Applications[END_REF]. In particular, simulations may misconceive the emotional response induced in realistic settings, such as stress, fear or panic [START_REF] Drury | Everyone for themselves? a comparative study of crowd solidarity among emergency survivors[END_REF].

Conversely, reports of Mixed Reality Games (MRGs) have unpacked people's interaction 'in the wild', for example how they achieve spatially distributed coordination to orchestrate a game [START_REF] Crabtree | Orchestrating a mixed reality game 'on the ground[END_REF]. More specifically, 'serious' MRGs have been suggested as an approach for exploring scenarios that are typically hard to study in the wild, such as DR [START_REF] Fischer | Serious mixed reality games[END_REF]. To clarify, we do not interpret the prefix 'serious' to mean that the game itself is inherently serious -players could still find it fun to play -more that the underlying research objectives are 'serious'.

We apply this approach to study HACs 'in the wild' by situating both agents and participants in real world environments, and presenting them with compelling game scenarios analogous to disasters. The objective is to study coordination, interaction and communication amongst actors while also having greater confidence in the efficacy of behavioural observations.

A shared understanding and situation awareness are key requirements for coordination in settings that involve human-agent interaction [START_REF] Bradshaw | Human-Agent interaction[END_REF]. We are particularly interested in how the coordination of DR can be supported and designed for by studying and designing for coordination in MRGs. In particular, MRGs share a common set of characteristics with DR scenarios that we outline in the following section.

Coordination in DR and MRG

Drawing on related work, we now illustrate some key characteristics that highlight how coordination is achieved in MRGs, and how these key characteristcs are shared with DR.

1. Bridging the physical and the digital. Both DR as well as MRGs routinely bridge the phyiscal and the digital as part of their actors' coordination [START_REF] Benford | Bridging the physical and digital in pervasive gaming[END_REF]. While DR for example makes use of the twitterverse to inform the real world response [START_REF] Sarcevic | Beacons of hope" in decentralized coordination[END_REF], MRGs provide hybrid spaces to enable playful and artistic performances and public experience [START_REF] Flintham | Where on-line meets on the streets: experiences with mobile mixed reality games[END_REF], often across different media [START_REF] Lindt | Designing cross media games[END_REF]. 2. Orchestration. The work of managing a DR as well as MRGs are highly orchestrated activities. Authoring and orchestration tools 'behind the scenes' of an MRG as well as player interfaces provide managers, players and spectators with different temporal and spatial views of the game world in order to support the experience [START_REF] Crabtree | Orchestrating a mixed reality game 'on the ground[END_REF]. These settings are somewhat comparable to the 'control room' of a first response operation, if only in their collection of various technological arrangements to communicate and coordinate real-time information streams to create a holistic as possible picture of the setting of interest. 3. On-the-ground and online. In both DR as well as (many) MRGs people on the ground work with people online to solve a common problem [START_REF] Flintham | Where on-line meets on the streets: experiences with mobile mixed reality games[END_REF].

In [START_REF] Sarcevic | Beacons of hope" in decentralized coordination[END_REF], the authors show how an understanding of online content can help to understand medical coordination challenges in DR from pre-deployment to on-the-ground action. MRGs often leverage the fact that people on the ground and people online have different views of the world that are turned into different abilities within the game. For example, Uncle Roy All Around You [START_REF] Benford | Bridging the physical and digital in pervasive gaming[END_REF] involved online and physical players collaborating in order to achieve a common goal -finding the mysterious Uncle Roy in the back streets of London.

Despite not being a comprehensive list, these key characteristics illustrate the overlap between coordination in MRGs and DR that underlie our motivation to explore the approach of serious mixed reality games further.

As a test bed for HACs in DR we designed and implemented an MRG called AtomicOrchid, that we continue to describe in this paper. In the following sections, we describe the game scenario, gaming and authoring interfaces, and the research-driven design rationale behind the game mechanics.

Game scenario. AtomicOrchid is a location-based real-time MRG based on the fictitious scenario of radioactive explosions creating expanding and moving radioactive clouds that pose a threat to responders on the ground (the field players), and the targets to be rescued around the game area. Field responders are assigned a specific role (e.g. 'medic', 'transporter', 'soldier', 'ambulance') and targets have specific role requirements, so that only certain teams of responders can pick up certain targets. For example, an 'injured person' can only be picked up by an 'ambulance' and a 'medic'. Field responders must not expose themselves to radioactivity from the cloud for too long, else they risk becoming 'incapacitated'.

In their mission to rescue all the targets from the radioactive zone, the field responders are supported by (at least one) person in a centrally located 'headquarters' room.

Player interfaces. Field responders are equipped with a 'mobile responder tool' providing them with sensing and awareness capabilities (see figure 1). The app shows them a reading of radioactivity, their health level, and a GPS-enabled map of the game area with the targets to be collected and the 'safe' drop off zones for the targets. They can also use the tool to broadcast message to the other field responders, and to headquarters.

Headquarters (HQ) is manned by at least one player who has at their disposal an 'HQ dashboard' that provides them with an overview of the game area, including real-time information of the players' locations (see figure 1). HQ can also broadcast messages to all field responders (not shown), and can review the responders' exposure and health levels. Importantly, only headquarters has a view of the radioactive cloud. 'Hotter' zones correspond with higher levels of radioactivity.

Authoring. We have designed a simple graphical authoring interface for Atom-icOrchid that allows non-programmers to set up a game on the fly, including specifying GPS-locations of the game area, targets, and drop-off zones. An important feature is that the game can be played anywhere (in principle), which is an essential requirement for deployments 'in the wild'.

Design rationale. It is worth mentioning that certain game mechanics are designed to allow us to explore specific aspects of coordination in HACs. Sensing and awareness of the environment are necessary requirements for coordination in DR. However, in order to create the need for more communication amongst HQ and field responders, the spatial position and movement of the cloud is only known to HQ. Furthermore, the specifics of role-target allocation creates the requirement for field responders to form 'agile teams' -forming, disbanding, relocating and re-forming continously in order to complete the game objective. Agile teaming is seen as one of the key challenges of DR that can be supported by computational agents [START_REF] Ramchurn | Coalition formation with spatial and temporal constraints[END_REF].

While the described game scenario does not include computational or embodied agents specifically, the scenario allows the creation of complex role-target allocations that, together with spatial and temporal constraints, provide an interesting use case for computational agent support. We will elaborate the integration of agents in AtomicOrchid in the next section.

Platform. AtomicOrchid is based on the open-sourced geo-fencing game Map-Attack 2 that has been iteratively developed for a responsive, (relatively) scalable experience. It is essentially a client-server platform relying on real-time streaming of location data built using the geoloqi platform, Sinatra for Ruby, and state-of-the-art web technologies such as socket.io, node.js, redis and Synchrony for Sinatra3 . Open source mobile client apps that are part native, part browser based exist for iPhone and Android; we adapted the Android app to build the AtomicOrchid mobile responder tool.

Researching HACs with AtomicOrchid

Complexity in role-target allocation in AtomicOrchid can easily become a bottleneck for human decision making, given the critical temporal constraints. Field responders may struggle to decide on the order of 'targets' to save, and how to efficiently coordinate re-grouping in the required teams. 'Coalition formation with spatial and temporal constraints' is a well-defined and difficult problem in the multi-agent systems community, for which a computational solution efficient enough to be applicable in a real-time scenario has been proposed [START_REF] Ramchurn | Coalition formation with spatial and temporal constraints[END_REF].

As an exploration of human-agent interaction in AtomicOrchid, we plan to integrate a computational coordinator agent that instructs field responders on when to form coalitions and which targets to rescue based on real-time analysis of the location and distances of responders and targets on the ground. Through a series of deployments, we will explore the effects of different interactional arrangements. Initially we aim to explore the following arrangements:

-The agent 'instructs' only headquarters, detailing teaming and target allocations for all responders. This arrangement relies on HQ 'translating' and delivering the instructions to the field responders. -The agent directly 'instructs' the field responders individually, detailing teaming and target allocations on an individual basis.

Further configurations of these arrangements include whether the instructions are delivered initially as a 'one-off' plan for the entire game, or whether the instructions are delivered 'just-in-time' after the completion of a sub-task, i.e. after a target has been dropped off in the safe zone. The configuration of interactional arrangements allows us to explore various ways in which human responders can be supported by computational agents.

The 2x2 factor research design achieved through the combination of interactional arrangement (agent-HQ vs agent-responder) and delivery mechanism (one-off vs just-in-time) can be enriched by considering further research questions of human-agent interaction, such as -How (and when) does the agent need to present the information or instructions most effectively to supports the responders' tasks? -Where do agents fit into existing human disaster response practices? -What are the benefits and shortcomings of using a software agent to instruct and assist disaster response compared to a human coordinator? -How can people best respond to agent instructions and how can the agent improve/learn from the human response?

In this paper, we proposed the application of serious mixed reality games to explore and design for coordination in disaster response scenarios. We introduced AtomicOrchid, a real-time location-based game to explore coordination and agile teaming under temporal and spatial constraints. We outlined the research plan by which we will study the various interactional arrangements in which human responders can be supported by agents in order to enable HACs in disaster response scenarios in the future.

Fig. 1 .

 1 Fig. 1. Player interfaces in AtomicOrchid.

www.orchid.ac.uk

http://mapattack.org/

http://bit.ly/rf4pQ7

Acknowledgements. This work is supported by EPSRC grant EP/I011587/1.


Robert Walter

Maic Masuch

Mathias Funk
email: m.funk@tue.nl

2 nd Workshop on Game Development and Model-Driven Software Development

Keywords: Game Development, Model-Driven Software Development, Domain-Specific Languages, Game Modeling, Game Authoring, Tooling, Prototyping

Succeeding the 1 st Workshop on GD&MDSD at last year's ICEC, this event continues the exchange of both novices and experts in the fields of game development and model-driven software development (MDSD). The overall goal is to further consolidate a platform for researchers and professionals who are interested in the topics of modeling, domain-driven design, and domain-specific languages in the context of game development. This year, we want to focus on future requirements in game design and development and how they can be addressed by MDSD techniques. The workshop covers questions like "how can game design benefit from the language engineering process?", "what are the pros and cons of visual and textual modeling languages?", and "how can modelto-model and model-to-text transformations be used to streamline game development workflows?".

Relevance of Workshop Topic

Games are highly interactive media applications within a hard to define common scope. Developed in multidisciplinary teams, they combine the artistic challenges of multimedia productions with the engineering challenges of IT-productions [START_REF] Hight | Game Development Essentials: Game Project Management[END_REF]. Hence, we face ambitious demands regarding the overall development process. However, the growing complexity and scale were not encountered by refined game development methods for many years [START_REF] Petrillo | What Went Wrong? A Survey of Problems in Game Development[END_REF]. Only recently, agile project management methods like Scrum were applied successfully in several productions [START_REF] Esmurdoc | Postmortem: Behind The Scenes Of Brütal Legend (11[END_REF], [START_REF] Graft | Racing Evolution: Forza 3 and the Changing Driving Sim[END_REF], [START_REF] Nutt | Q&A: Valve's Swift On Left 4 Dead 2's Production[END_REF].

In the last decade, MDSD has successfully made the transition from the academic sphere to industrial-grade software development and it provides many advantages [START_REF] Stahl | Model-Driven Software Development: Technology[END_REF] game development could benefit from. Key features of a system are formally described on a higher level of abstraction (the problem domain), omitting distracting details like the technical realization on a distinct platform (the solution domain). This allows for a better integration of domain experts (e.g. game designers, game writers, concept artists) in the development process, faster iteration times, and implicit system documentation. Using code generation, the transition from problem space to solution space can be automated, which is more efficient and less error-prone than the manual implementation in a third generation language. Moreover, games feature characteristics of software product lines. Since product-line engineering is an explicit application field of MDSD [START_REF] Stahl | Model-Driven Software Development: Technology[END_REF], we see a perfect fit of game development and MDSD. By means of expressive and engaging software tools such as DSLs and generative tooling content authors and game designers are strongly integrated into the development process. That is why we think that game development and MDSD should get in touch in an ICEC workshop, which is an excellent setting for the much needed professional exchange of ideas, feedback from diverse experts, and lively discussions.

Workshop Objective

The workshop's main objective is to bring together researchers and professionals of both fields to identify how game development could benefit from MDSD and vice versa. This year, we focus on upcoming requirements in game development fields like novel authoring tools, scripting and programming languages, and agile workflows.

Proposed Form and Schedule

In order to accomplish the described objective, we plan to provide a full day workshop that is divided into five sections. 8:30 AM Introduction and Overview : We start with welcoming all participants, presenting the results of last year's workshop, and giving an overview on the workshop's schedule and goals. 9:00 AM Future Challenges and Possibilities: This section comprises two keynotes. One keynote is meant to illustrate the future challenges in game development. The second keynote will introduce current and upcoming developments in MDSD. Markus Vlter, author of several articles and books on MDSD (e.g. [START_REF] Stahl | Model-Driven Software Development: Technology[END_REF]), already expressed his interest in doing this keynote.

11:00 AM Position Papers: Selected researchers and industry professionals present their experiences and opinions on "model-driven game development", covering theories, techniques, tools, infrastructure, and boundaries of MDSD. In combination with the former section, this builds the basis for the upcoming panel discussion.

2:00 PM Panel Discussion: The panel discussion will be a moderated talk with two invited experts of each field (game development and MDSD). They will discuss the application possibilities of model-driven techniques in the context of future challenges in game development and how the agile development nature of games might influence MDSD techniques. The audience is meant to take an active part in the discussion, raising questions, commenting statements, and giving answers.

4:30 PM Retrospective: The first three sections are going to be protocolled by the workshop organizers. In the final section, they present the protocol to identify and evaluate the findings of the workshop together with the participants. As a result, this should lead to a compilation of valuable research and development questions.

5:00 PM Close.

Expected Workshop Outcome

The organizers will compile the results of the workshop, especially the identified research and development questions, in a white paper which will be published on the website of the workshop. In addition, the accepted position papers are published as part of the conference proceedings. The workshop website shall continue to be used as a means to connect the participants, facilitate further discussions and information exchange, and promotion of subsequent events. Another concrete result could be the planning of a special issue devoted to the workshop topic in a suitable journal such as Entertainment Computing or Computers in Entertainment.

Bio Information of Workshop Organizers

Robert Walter received a diploma in Software Engineering and a Master of Science in Computer Science. In his Ph.D. studies, he examines the game development process with a focus on the creation and processing of narrative game content, develops concepts for domain-specific languages (DSLs) 3 , and tools for an improved integration of all stakeholders-from game writers over artists and voice actors to localization studios-into the game development process. The goal is to find patterns that reduce development time, effort, complexity, and costs.

Maic

  Masuch holds the chair of Media Technology and Entertainment Computing at the Faculty of Engineering, Department of Computer Science and Cognitive Science at the University of Duisburg-Essen. He received his Ph.D. with a dissertation on computer animation at the University of Magdeburg and, in 2002, became Germany's first Professor for Computer Games. He founded two companies, researches in the field of game design and game development for over twelve years, and is one of the pioneers of German video game research.

"[A DSL is] a computer programming language of limited expressiveness focused on a particular domain."[START_REF] Fowler | Domain-Specific Languages[END_REF]

Mathias Funk is a Postdoctoral Researcher at the Designed Intelligence group in the Department of Industrial Design of the Eindhoven University of Technology (TU/e). After graduating from RWTH Aachen University in Computer Science he did a PhD at TU/e on the topic of adaptive data collection from commercial products in the field. He is cofounder of UXsuite, a startup company for product experience analytics software. Among others, his research interests are domain-specific languages for creative stakeholders, rapid prototyping, and user experience.

Further Information

Further information on the workshop can be found at the workshop site http: //gd-mdsd.blogspot.com/.


Larissa Müller

Svenja Keune

Arne Bernin

Florian Vogt

Emotional Interaction with Surfaces -Works of Design and Computing

Here we present three interactive artworks that showcase the abilities of active textured surfaces to enable new qualities of surface interactions. Giving the surfaces different sensing abilities, ways to act and behaviors, then allows us to explore emotional attributes and character perceived by an observer. The three designs reflect artworks emotional perception of the observer and the resulting effects on behavior. The surfaces sense it's surrounding in terms of physical presence by proximity and emotional state based on facial expression. The surface can express its emotion with a change in movement and sound. The three surface designs explore further combinations of textile surfaces, sensors and reactive actuation to draw on the emotion of observers.

Introduction

Surface interfaces are predestined for manual and visual interaction, since they merge the modalities of physical input and visual output. Now, commonly used multi touch screens, particularly for mobile applications, enable physical interaction with planar rigid surfaces. Recent works have developed deformable interaction surface systems, which allow the incorporation of passive material attributes with surfaces in the physical interaction to enhance tactile feedback [START_REF] Vogt | A malleable surface touch interface[END_REF][START_REF] Smith | Low-cost malleable surfaces with multi-touch pressure sensitivity[END_REF]. In our work we explore concepts of active surfaces, which are composed of interactive elements, inspired by repeating features in nature, in our case of animal scales, to find a trade-off between manufacturability and to form elaborate complex behavior of the overall surface structures. We see the potential to exploit these extended surface design spaces to form character, emotional attributes, and physical sensations to create compelling interaction.

We build on interactive works which combine emotional models and reactive objects based on facial [START_REF] Becker | Evaluating affective feedback of the 3d agent max in a competitive cards game[END_REF], characteristic [START_REF] Breazeal | Emotion and sociable humanoid robots[END_REF] and animalistic [START_REF] Wada | Analysis of factors that bring mental effects to elderly people in robot assisted activity[END_REF] physical artifacts. A number of emotional models have been developed to analyse human behavior and to create interactive systems. While in many existing works a strong association with prior experiences exists, we explore the mapping of behaviors. Less established associations are tread as degrees of freedom in a design space and let us guide by the affordances the designs provoke to find compelling mappings, with the goal to explore the ability of active surfaces to provoking and further respond to emotions of observers.

The works we developed are a part of an iterative process, based on the ideas from Mitch Resnick of a "'Lifelong Kindergarten"' [START_REF] Resnick | All i really need to know (about creative thinking) i learned (by studying how children learn) in kindergarten[END_REF]. A circle with the steps Imagine, Create, Play, Share and Reflect leads to fast prototypes. It also offers the possibility of creative working. The works we present consists of three different degrees of interaction. The first surfaces operates without any kind of sensor. The second one uses a distance sensor and the third is triggered by a visitors emotion, recognized from his face. We made tests with hundreds of visitors in which we were provoking some kind of interaction. 2 Description of three Surface Designs

In the following we describe the three interactive artworks: Estoban, Mocoleme, and Lomelia that were created by the authors team with design and computer science backgrounds in terms of design concepts and interaction technology. Estoban and Mocoleme are focused on a relationship between sound atmosphere, movement und textile surface. Estoban affects the atmosphere in different urban spaces (private or public), and also has presence, the communication with Mocoleme is very simple. The intention is to have an affect on urban spaces and private rooms. Nature and urban sounds are calming, better than silence, which is often perceived as unpleasant and better for concentration or worklife than music. She reacts to distance with emotions, which are expressed by sounds and movement. Lomelia is based on a more complex kind of communication between an object and its observer. She includes the emotions of the observer to the interaction.

Estoban -Urban Stories

Estoban tells stories with sound. He creates a relaxed atmosphere and tells about his adventures from time to time. He shows his emotions in a subtle way. The border between reality and virtuality becomes fluently blurred. A direct contact to his surrounding is not what he looks for. He deals perfectly well with minimal attention. The attention received by listening to his stories is quite surprising. We produced this first surface without any sensory input as an emotion backchannel. The displayed emotions are selected randomly. The output is using sound and movements to express and trigger emotions.

Mocoleme -Come Closer

Mocoleme likes to receive attention. If she feels neglected her mood changes quickly. She gives her opinions free running and is hardly affected. Once understood, you can play with Mocoleme in a wonderful way.

In this object we use distance as sensory input. The expression of emotions also appropriates sound and movements. The objective of this is to find out about preferences with respect to the input.

Lomelia -Emotional Dialogue

The emotions of an observer should not just be mirrored by the surface, but affect actions and emotions of visitors. It may get bored, for example, if a person is happy or be surprised following an anger outburst. She tries to frighten someone if the person is scared or gets annoyed by a lack of interest. The aim here is to express emotions by its movement.

The third surface, Lomelia, uses the SHORE library [START_REF] Kueblbeck | Face detection and tracking in video sequences using the modified census transformation[END_REF] from the Fraunhofer Institut of Integrated Circuits IIS as sensory input. This Software recognizes emotions from a visitors face. It gives a conclusion of the emotional states angry, happy, sad, or surprised. The camera placed on top of the surface is used to obtain an accurate picture of the current user. The servo motors are triggered by the assumed emotional states.

The overall system is separated into two modules with different functions: emotional display and emotional backchannel. The interfacing between these two modules is implemented via a central message broker that employs the publishsubscribe pattern. This enables the design to be flexible for further enhancements such as adding more modalities for input or output. The input module is implemented with infrared distance sensors and a camera that captures the faces of observers. The resulting images are emotion interpreted based on facial expressions implemented with the SHORE library [START_REF] Kueblbeck | Face detection and tracking in video sequences using the modified census transformation[END_REF]. The output module consists of a microcontroller to manage the servo motors of the interactive surfaces. All three active surfaces are constructed from fabric covered shell like base elements (Shown in Fig. 1c).

Summary

The three surface artworks demostrates the concept of active surface to facilitate the possibilities of emotional interaction. The benefit of our interactive installations is that they are made of textiles. By an invisible technique the observer becomes focused on haptic allure, physical qualities and movements. The degree of emotional perception of the artworks exhibited here allow different forms to engage the observer. Informal exhbits of the artworks have provided much positive feedback, demonstrating that active surfaces can produce emotional experiences. The concepts presented here show that emotional awareness interfaces, inspired by human-human communication, with basic expressions can be highly engaging for participants. This technology could be transfered to enterainment computing through the exchange with researchers in the field.

Fig. 1 :

 1 Fig.1: Emotional interaction triggered by: (a) random movements (degree one), (b) distance to the object (degree two), and (c) facial expression (degree three)

Acknowledgement

We thank Kai von Luck, Renata Brink, Gunter Klemke, Birgit Wendholt and Franziska Hübler for their feedback and their support for this work. Further we express our gratitude to the members of our EmotionLab for supporting the construction of the artworks. In addition, we thank the Fraunhofer Institute of Integrated Circuits IIS for providing the SHORE library.


Sandra Siegel
email: siegel@tzi.de

Jan Smeddinck
email: smeddinck@tzi.de

Adaptive Difficulty with Dynamic Range of Motion Adjustments in Exergames for Parkinson's Disease Patients

Keywords: serious games, parkinson's disease, motion-based games, exergames, difficulty adaptation, elderly entertainment

Motion-based video games offer great promise in the support of traditional physiotherapy and are currently explored in a growing number of research projects. With a focus on Parkinson's disease (PD) patients, their therapeutic needs and strong individual differences in capabilities, this work describes an approach to dynamic difficulty adjustments in an exergame tailored for PD patients. The automated ongoing adjustment of the required range of motion, the amplitude parameter, is introduced as an important aspect of such adaptations. Results from a first case study suggest that the approach is viable and appreciated by therapists, yet could benefit from increased flexibility.

Introduction

Parkinson's disease (PD) is characterized by a variety of motor and non-motor symptoms [START_REF] Goldenberg | Medical management of parkinson's disease[END_REF]. Regular physical activity in therapy sessions and auxiliary exercises at home play a central role in slowing down the progression of the neurological disease and in improving the patients' quality of life [START_REF]Parkinson's Disease Society: The Professional's Guide to PD[END_REF]. It is important to motivate patients to participate in these activities and to put effort into performing the often repetitive exercises. Exergames, as motion-based video games, offer great promise in augmenting existing therapy sessions and home exercising by providing additional guidance, feedback and motivation. Our work is based on the WuppDi! exergames suite for PD patients (cf. [START_REF] Assad | Motion-Based games for parkinson's disease patients[END_REF]). Evaluations of this project have shown that the chance of enriching the spectrum of tools around physiotherapy is appreciated by patients and therapists alike. However, the target group of PD patients has very specific requirements that are dominated by the need to cater for strong individual differences in the mental and physical abilities and limitations of the players that result from different states of disease and symptoms, effects of normal ageing and fluctuations over the course of a day [START_REF]Parkinson's Disease Society: The Professional's Guide to PD[END_REF]. Typical game-difficulty modes (e.g. easy, medium, hard) encompass multiple game-play variables and do not allow for the required finegrained control. We introduce a system that implements an ongoing adaptation of difficulty parameter settings for individual players, focusing on the automated adaptation of their range of motion (ROM). The system, which also adapts parameters for speed and accuracy, was tested in an initial case study over the course of three weeks, in order to determine whether the individual settings can successfully be adjusted over time, aiming for an improved range and quality of motion, while providing a positive game experience.

A Brief Overview of DDA for Exergames and a PD Specific Implementation

Dynamic Difficulty Adjustments (DDA) are an important matter of research in relation to motion-based games for the support of physiotherapy for PD patients.

The need for personalization in order to accommodate for strong differences in capabilities between individuals is a core requirement that has been identified in prior research [START_REF] Assad | Motion-Based games for parkinson's disease patients[END_REF] and related research with other heterogeneous target-groups, such as institutionalized older adults [START_REF] Gerling | Full-Body Motion-Based game interaction for older adults[END_REF] and stroke patients [START_REF] Alankus | Towards customizable games for stroke rehabilitation[END_REF]. This adaptation needs to be automated, because therapists cannot afford to make frequent manual adjustments for every individual patient. To date, related research seldom focused on the specific use-case of exergames for PD and largely omitted the aspect of automatic ROM adaptations, which we discuss here as the game-difficulty parameter amplitude. In addition to the more commonly studied difficulty parameters for speed and accuracy [START_REF] Alankus | Towards customizable games for stroke rehabilitation[END_REF][START_REF] Geurts | Digital games for physical therapy: fulfilling the need for calibration and adaptation[END_REF], the amplitude is an important aspect, since wide fluent movements are a crucial component of PD physiotherapy [START_REF] Assad | Motion-Based games for parkinson's disease patients[END_REF]. We implemented and tested DDA for Sterntaler, one of the WuppDi! games [START_REF] Assad | Motion-Based games for parkinson's disease patients[END_REF].

In the game, the player is tracked by a Kinect 1 sensor and follows differently shaped trails of stars with one hand. The position of the playing hand is mapped to a hand-shaped cursor that is used to collect the stars for points. Here, game difficulty is composed of the time available to collect all stars before they automatically disappear (speed ), the size of the cursor with which the player has to hit the stars (accuracy) and the amplitude of movements the player has to perform to reach all stars. The latter is controlled by a scale factor that is applied to the mapping of tracked movements to the cursor, making it easier or harder to reach stars further away from the player. The three difficulty parameters are automatically adapted after each game round based on the player's performance in that round and additionally slightly decreased for the first game of a new game session in order to provide for a warmup round. Speed and accuracy settings change based on the rate of collected to non-collected stars and the completion time. For the adaptation of the amplitude setting, the collection rate is weighted by the distance of stars from the rest position of the play hand. Additionally, the motion profile of the play hand is consulted for inferring if non-collected stars were not accessible or if they could have been reached by the player (i.e. the player has moved his hand to the respective position before). Optionally, a calibration based on three predefined poses can be performed to determine a suitable amplitude setting for the first game and to constrain dynamic amplitude adaptation to a reasonable maximum. This process must be monitored by therapists and the results can be manually adjusted to match therapeutic constraints or goals.

Case Study

The system was applied in a case study with three male PD patients aged 64, 76, and 76, spanning five sessions per participant over a period of three weeks. Each participant played 16 game rounds with either hand. The evaluation was based on observational data, self-reported ratings of participants concerning the perceived difficulty and their game experience, game logs (difficulty settings, performance data and motion profiles) and video recordings that were analyzed together with associated physiotherapists. Due to the limited scope of this paper we focus on presenting the results related to amplitude adaptation (cf. [START_REF] Siegel | Adaptive Difficulty in Exergames for Parkinsons Disease Patients[END_REF]). The course of the amplitude settings is depicted in figure 1. The starting settings applied in the first round were determined by calibration and settled 40cm below the calibrated amplitude. These settings are quite distinctive as they respond to the different motion capabilities of the three participants and their body height (ca. 1,7m for P1/P2 and 1.98m for P3). As expected, due to the easy start settings, the required ROM steadily increases in almost all cases during the first game rounds until the calibrated constraints are reached. P2 (right) differs from the general trend due to the participant's individual problems in raising his right arm vertically and reaching the central upper area of the screen. Physiotherapists, when analyzing video recordings at different amplitude levels, underlined the importance of the provided individual and dynamic amplitude settings. The high level settings were seen as increasingly suitable and effective as participants needed to fully stretch their arms and their back.

While the upward trend in amplitude settings clearly illustrates the adaptation mechanism at work and therapists confirm that the adaptation approach generally provided suitable amplitude settings for our participants, some issues remain that demand for more flexibility in the adaptation mechanics: For P2 raising his right arm vertically was difficult, while stretching it to the sides was well possible, resulting in a low amplitude setting that did not get him to exploit his whole horizontal ROM. P1 suffers from a severely flexed spine (camptocormia) and an important focus in his exercises lies on stretching his trunk. Therapists therefore recommend to select star trails that motivate vertical movements and require a large range of motion while restricting the range horizontal movements, since these could possibly compromise his balance.

Conclusion

DDA in exergames have the potential to make them more useful and efficient, especially for heterogeneous target-groups with shifting needs like PD patients. The case study illustrated how such adaptations can work based on heuristic performance measures and highlighted the importance of an amplitude parameter in exergames for PD patients. However, the data analysis and therapist comments suggest that the system needs to be more flexible and allow for finegrained control to encompass individual strengths and weaknesses (e.g. vertical vs. horizontal ROM). A more distinctive area-based performance analysis and more frequent live adaptations, based on a wider spectrum of feedback metrics, could be viable approaches to these challenges. Lastly, improving and evaluating DDA in exergames requires long-term studies with more subjects and the possibility to correlate game-performance data to reliable medical data.

Fig. 1 .

 1 Fig. 1. The amplitude settings, which correspond to the diameter of movements necessary for covering the screen, for the three participants over all game rounds.

http://www.kinectforwindows.org


Pongpanote Gongsook
email: p.gongsook@tue.nl

Time Simulator in Virtual Reality for Children with Attention Deficit Hyperactivity Disorder

Keywords: Time Perception, Virtual Reality, Game, Attention Deficit Hyperactivity Disorder, Learning Disorders

This project aims at investigating how effective virtual reality is in manipulating and eventually training time perception for children with learning and/or behavior disorders. The interconnectivity of multiple brain regions is needed for time perception. Small dysfunctions in these brain regions may cause time perceiving problems. Likewise, children with attention deficit hyperactivity disorder (ADHD) appear to have comparable dysfunction in time orientation. However, the time perception can be trained in their early ages. In addition, research confirms the effectiveness of virtual reality in improving the sequential time perception of children with mental retardation. This paper presents the theoretical and empirical framework that uses a virtual reality time simulation game for training time perception of children with ADHD.

Introduction

Time is something humans cannot directly perceive with their senses. However, it can be perceived by reasoning on one's surrounding context or the sequence of events that happen within one's local environment [START_REF] Le Poidevin | The Experience and Perception of Time[END_REF][START_REF]Time Perception[END_REF]. Children as young as 3 year old start developing their sensitivity to duration, and their time perception develops with age [START_REF] Droit-Volet | Alerting attention and time perception in children[END_REF]. Time perception is a conceptual understanding that enables one's ability to predict, anticipate, and respond to events as past or present occurring in the environment [START_REF] Le Poidevin | The Experience and Perception of Time[END_REF][START_REF]Time Perception[END_REF]. Children with attention deficit hyperactivity disorder (ADHD) have shown their difficulties in processing, reading, and telling time [START_REF] Hurks | Retrospective and prospective time deficits in childhood ADHD: The effects of task modality, duration, and symptom dimensions[END_REF]. Although there are quizzes and tests on the internet that aim to improve children's time reading [START_REF]Learn to Tell Time Games & Websites for Kids[END_REF], most of them are designed for normal children. We aim at a virtual reality game that creates a time simulator for children with learning disorders and ADHD.

Connectivity between Time, Brain functions and ADHD Time perception needs the interconnectivity between multiple brain regions, including the cerebellum, basal ganglia, and prefrontal cortex. Individuals with cerebellar dysfunction may have difficulty with an event that requires precise movement timing [START_REF] Toplak | Temporal information processing in ADHD: Findings to date and new methods[END_REF][START_REF] Casini | Effects of divided attention on temporal processing in patients with lesions of the cerebellum or frontal lobe[END_REF]. The basal ganglia, prefrontal cortex, and posterior parietal cortex have been suggested to be involved in interval timing [START_REF] Hurks | Retrospective and prospective time deficits in childhood ADHD: The effects of task modality, duration, and symptom dimensions[END_REF].

The mentioned brain regions are found to be involved in the dysfunction of time perception during cognitive testing in the ADHDs [START_REF] Smith | Evidence for a pure time perception deficit in children with ADHD[END_REF]. ADHD is a behavioral condition identified by DSM-IV [START_REF]DSM-IV-R: Statistical Manual of Mental Disorders, Text Revision (DSM IV--R)[END_REF], which symptoms must be present before the age of seven, persist for at least six months, and be sufficiently severe to impact daily functioning across several settings such as home, school and interpersonal relationships. Children with ADHD have significantly smaller cerebral and cerebellar volumes, particularly the right cerebellum [START_REF] Toplak | Temporal information processing in ADHD: Findings to date and new methods[END_REF]. Besides, there are significantly lower levels of activation in the basal ganglia in children with ADHD [START_REF] Hurks | Retrospective and prospective time deficits in childhood ADHD: The effects of task modality, duration, and symptom dimensions[END_REF]. However, rehabilitation as well as training could be done while they are in the early developmental stages [START_REF] Barkley | Sense of time in children with ADHD: effects of duration, distraction, and stimulant medication[END_REF].

Virtual reality as a diagnostic/training game

Virtual reality (VR) can be used in many aspects and application areas. VR simulations allow children with certain impairments to experience what could be difficult or even impossible for them to do in reality [START_REF] Rose | Learning and memory in virtual environments: a role in neurorehabilitation? Questions (and occasional answers) from the University of East London[END_REF]. Fairley suggested that patients would feel more amused when they are rehabilitated using games that utilize VR [START_REF] Fairley | Fun and Games: Virtual Reality Turns the Work of Rehab into Play[END_REF]. Riva, Mantovani, and Gaggioli show that knowledge obtained in VR can be transferred into a real environment [START_REF] Riva | Presence and rehabilitation: toward secondgeneration virtual reality applications in neuropsychology[END_REF]. It is shown that participants who performed cognitive tasks that targeted on attention performance using VR did outperform scores of those who used the traditional methods [START_REF] Parsons | A controlled clinical comparison of attention performance in children with ADHD in a virtual reality classroom compared to standard neuropsychological methods[END_REF]. However, we have found no existing effort in training time perception using a Game in Virtual Reality Environments (GVR).

Project approaches

We aim at GVRs that children with ADHD can play in, and at the same time offers opportunities to train and improve their time perception. Gaming is chosen because it can immediately give them rewards, which they attract to [START_REF] Bioulac | Attention deficit/hyperactivity disorder and video games: A comparative study of hyperactive and control children[END_REF]. GVR aims at improving the working memory of children with ADHD, which found out as one of their core cognitive deficits [START_REF] Dehn | Working Memory and Academic Learning Assessment and Intervention[END_REF]. Improving the working memory might reduce some of their symptoms and associated behavior problems [START_REF] Klingberg | Training of working memory in children with ADHD[END_REF]. Mnemonic strategy, which encoding the information in a way other than directly remembering, will be used in this project [START_REF] Mastropieri | Enhancing School Success with Mnemonic Strategies[END_REF].

The GVR uses linear storytelling so we can ensure that all the children experience the same branch of decisions. It includes mini games for specific memory tests for time estimation, production and reproduction. The game trains the children's time perception using various time teaching techniques such as clock faces or the appearance of the sky at different times of the day. It uses game-world time while teaching and uses real-world time while testing [START_REF] Zagal | Temporal frames: a unifying framework for the analysis of game temporality[END_REF]. Before GVR is used as a psychological assessment tool, it must be evaluated by psychologists.

Conclusion

The goal is to investigate how effective time simulation in virtual reality is for children with learning disorders. Children with ADHD have time perception problems. However, their symptoms can be cured in their early ages. We believe that children with ADHD will have some benefits from learning time perception via GVR. The time simulator in virtual reality can be a candidate for the solution.


Oswald D Kothgassner

Anna Felnhofer

Leon Beutl

Helmut Hlavacs

Mario Lehenbauer

Birgit Stetina

A Virtual Training Tool for Giving Talks

In this paper we present two studies concerning the application of a virtual environment for public speaking anxiety. We have created a program simulating a virtual lecture room, which can be filled with a large number of listeners behaving in different ways. The purpose of the scene is to train people who are anxious to give talks in front of a large audience. We present the results of two studies, showing the impact of this kind of virtual exposure. Results indicate that people do experience such a situation as realistic, as well as report social insecurity and show heightened psychophysiological arousal (HR). Furthermore, we show that especially curious people, and people with high social insecurity rate the system as useful.

Introduction

Social phobia (or social anxiety disorder, SAD) is a well-defined disorder in the DSM-IV. Individuals with social phobia suffer from a marked and persistent fear of one or more social or performance situations in which the patient is exposed to unfamiliar people or possible scrutiny by others. These patients suffer from maladaptive cognitions concerning the self-image and/or their own behavior in social situations (including a ruminative cognitive style) and furthermore they experience a physiological hyperarousal.

For treating phobia in general, people with social anxiety are often exposed to situations they are afraid of, and try to gradually adapt to them, thus decreasing the subjectively felt fear. Examples include, e.g., fear of certain animal types like spiders or dogs, fear of heights, places, situations, etc. Social phobia is special since it always involves other people, and treatment as described above involves the presence of a possibly large number of real humans, a scheme that is often impractical for psychological training and therapy.

In contrast, exposing people with social anxiety to virtual situations by using videos or computers offers the potential of creating arbitrary situations with limitless other (virtual) human beings. In virtual reality (VR) one can interface with the environment, usually through peripheral devices, such as head-mounted displays and keyboards. By watching the scene through a head-mounted display, the patient should be immersed into the virtual scene, and ideally perceive the same or comparable stimuli as in real situations.

However, virtual exposures to flight, heights and social settings are well studied for psychological practice and can be more cost-and time-effective for both therapists and patients, thereby improving the accessibility of therapy to individuals who may previously have been unable to afford treatment. Newman et al. [START_REF] Newman | A review of technology-assisted self-help and minimal contact therapies for anxiety and depression: Is human contact necessary for therapeutic efficacy?[END_REF] estimated a savings of 540$-630$ per client when compared with standard individual therapy. Also, the use of inherently motivating virtual reality scenarios containing gaming aspects such as stimulating content and diverse levels of achievements has recently become very attractive. Especially so called serious games are increasingly applied in psychological therapy and training as they constitute a valuable endorsement of common cognitive behavioral approaches (for a detailed description see below). However, it is still an open question whether virtual exposure always achieves the same impact on patients compared to real situations, and which factors determine the efficacy of virtual exposures.

In this paper we demonstrate the efficacy of the virtual training tool for giving public lectures in front of an audience. The scene is 100% virtual, rendered in a computer using modern graphics cards and an open source render engine. We describe the software and results from experiments with a large sample size.

Related Work

Psychophysiological theories suggest that patients who suffer from social phobia experience heightened physiological arousal when they enter social situations. They interpret this arousal as an indication of danger or anxiety [START_REF] Gerlach | Public and private heart rate feedback in social phobia: a manipulation of anxiety visibility[END_REF] and this leads to increased symptoms of anxiety (e.g., a racing heart, blushing). Individuals therefore learn to avoid social situations to evade this psychophysiological arousal [START_REF] Anderson | The relationship among social phobia, objective and perceived physiological reactivity, and anxiety sensitivity in an adolescent population[END_REF][START_REF] Mauss | Autonomic recovery and habituation in social anxiety[END_REF]. Cognitive models of SAD highlight the centrality of fear of negative evaluation in the onset and maintenance of this disorder [START_REF] Clark | A cognitive model of social phobia[END_REF][START_REF] Laposa | Interpretation of positive social events in social phobia: an examination of cognitive correlates and diagnostic distinction[END_REF].

The goal of our approach is guided by the psychophysiological assumptions as mentioned above and the cognitive model by Clark and Wells [START_REF] Clark | A cognitive model of social phobia[END_REF]. According to this model, anxious people who enter feared situations believe, that (1) they are in danger of behaving in an unacceptable manner and (2) that such behavior will have disastrous consequences. The avoidance behavior is a complex constellation of cognitive, behavioral and psychophysiological changes, the danger is more imagined than real with anxiety responses (both physical and cognitive) being mostly inappropriate [START_REF] Clark | A cognitive model of social phobia[END_REF]. Cognitive-behavioral treatment methods (CBT) focus on changing maladaptive cognitions, psychophysiological reactions and include body relaxation training (such as biofeedback). Patients who undergo this kind of treatment report gaining a sense of empowerment and knowledge about how to best control their physiological symptoms [START_REF] Wiederhold | Virtual Reality Therapy for Anxiety Disorders[END_REF].

The efficacy of technology-aided exposition methods has been shown to be comparable to traditional face-to-face settings [START_REF] Cote | Virtual reality exposure for phobias: A critical review[END_REF][START_REF] Newman | A review of technology-assisted self-help and minimal contact therapies for anxiety and depression: Is human contact necessary for therapeutic efficacy?[END_REF][START_REF] Parsons | Affective outcomes of virtual reality exposure therapy for anxiety and specific phobias: A meta-analysis[END_REF][START_REF] Wiederhold | Virtual Reality Therapy for Anxiety Disorders[END_REF]. VR can be combined with the compelling and motivating character of (serious) games which offer huge varieties of social interactions with other users or computer generated agents [START_REF] Caplan | Problematic Internet use and psychosocial well-being among MMO players[END_REF][START_REF] Kothgassner | Behavior beyond the world of online gaming[END_REF]. There are several serious games for health with promising results available, such as Re-Mission (provides knowledge about cancer), Snow-World (to distract burn recovery patients from pain), or Sparx, an online role-playing game for the treatment of depression 4 . Yet, for serious game developers it is a great challenge to find the right balance between a sufficient level of stimulation and motivation and at the same time satisfy the requirements of the cognitive behavioral treatment approach. Thus, studies concerning the users' perceptions of such scenarios as well as investigations regarding efficacy, usability and usefulness are required to provide entertainment computing specialist with sufficient knowledge.

In this paper we present the results from two studies concerning virtual exposures to a lecturing situation. It is well known that many people fear giving talks in front of large audiences. Examples for virutal training of giving public speeches are the products of Virtually Better,5 often a mixture between pure virtual surroundings and real people filmed by video, or Virtual Reality Medical Center 6 , a video that is presented through a visor. Another example using real people as a virtual audience is the Internet based tool Talk To Me [START_REF] Botella | A self-applied Internetbased intervention for fear of public speaking[END_REF], whose efficacy is researched in [START_REF] Botella | An Internet-Based Self-Help Treatment for Fear of Public Speaking: A Controlled Trial[END_REF].

In contrast, we created a purely computer based scenario, using only virtual surroundings and artificial characters, in order to be able to synthesize different settings (e.g. varying sizes of the audience, different emotional expressions of the listeners). We present results from detailed analyses of the experiments, both indicating the efficacy of the virtual exposure and identifying factors which determine the usefulness of such a tool.

Virtual Training for Lecturing

This application allows users to virtually act out a situation in which they are supposed to give a lecture to an adjustable amount of people. The virtual environment consists of a room with space for about a hundred people. Since this room is supposed to resemble a lecturing hall, it has high walls with large windows, and small lights placed on the ceiling. Within the room there are two seating areas, a main one consisting of eighty seats in the middle of the room and a tribune in the back, resting on two columns. This main seating area is separated into a left and a right part, with a corridor between them. In this area 3 dimensional virtual avatars are placed in rows of red seats, with a table in front of each row. The last rows and the tribune are, when adjusted, filled up with 2 dimensional sprites, which is not noticeable at this distance and increases the performance of the application. As an example, Figure 1 shows the room with 70 people and fill sprites in the back. To increase the realism of the scenario additional items which may be brought to a lecture are added for each avatar, like bags, magazines or laptops. The 3 dimensional avatars, both males and females, who simulate the audience have a number of animated seating poses, between which they change independently after a certain amount of time to create some liveliness. Additionally there are three different facial expressions, neutral, happy and hostile which can be changed in the options menu. The avatars also blink in irregular time steps and close their eyes when they mimic a sleeping position. The view of the test person is from a small, slightly elevated stage in front of the main seating area. Small stairs to the right and left of the stage lead up to it. On the stage there is a large screen behind and to the left of the test person, and a podium in front of him. The podium provides an additional small screen and a virtual microphone. On both screens slides for the lecture are displayed. The position of the test person is fixed, only his view is controllable. A virtual avatar is placed on the same position, so when the test person looks down, he sees parts of his body. After adjusting the settings explained in Section 3.1, the simulation starts and the test person has to give a lecture as he would do in front of a live audience. While doing so, the 3 dimensional avatars will display different poses and expressions during the speech, happy, hostile or tired ones. If adjusted, a request to speak louder or laughter will be heard after a certain amount of time, similar to a real lecture. Also, the real slides of the lecture can be imported into the application and are then displayed upon the big screen behind the test person and the small one on the podium. These slides can be switched upon pressing a button and can aid the lecturer during the speech.

Options

Before starting the application there are some settings that can be adjusted to alter the appearance and the perception of the simulation. The following list describes the available options:

1. Number of people: Here the number of 3 dimensional audience avatars is adjustable, and ranges from zero to seventy, which is about the maximum the main seating area can hold. This option has the most influence on the performance of the application, since visualizing the avatars is the most intensive in terms of computation. 2. Percentage of happy people: With his option the expression of a certain number of people can be changed. It defines the percentage of avatars with a smiling expression. What avatars this expression is assigned to is decided by change. 3. Percentage of sleeping people: This option allows to define a number of sleeping avatars, which do not change expression but rest their head on their arms on the table before them, mimicking a sleeping pose. 4. Percentage of hostile people: With this option the expression of a certain percentage of avatars can be changed to hostile, which will result in a frowning face with lowered mouth corners. 5. Background sound: Currently there are only two possible sounds, a rather silent one with only quiet talking and some coughing, and a noisy one. These can be used to fit the number of people or to set a certain mood for the lecture. 6. PowerPoint Slides: This option defines the number of slides to be used in the application. All available slides are stored in a predefined folder and have to have a consecutive numeration. However, with this option it is possible to use only a certain number of slides in the current test. 7. Time offset for request: This defines the number of seconds after which a request to speak louder will be heard from the audience (see Figure 2). The values reach from zero to 1800, where zero means no request at all. 8. Time offset for laughter: This defines the number of seconds after which a loud laughter from the audience will be heard. The values reach again from zero to 1800, where zero means no laughter at all. 9. Add sprites: If the maximum of seventy avatars is not enough for a test, and an even bigger audience should be simulated, then this option provides the possibility to fill the back of the main seating area and the tribune with 2 dimensional sprites.

Fig. 2. A person asking the participant to speak louder. Some listeners are sleeping.

Technical Implementation

The application was developed by a group of students during a practical course at the University of Vienna, using Visual Studio C++ Express and the Ogre3d graphics engine in combination with QuickGUI. All the 3 dimensional models were created in Blender3D and the textures were processed using Gimp.

For the creation of the models, especially the human faces, a simple technique was helpful by which a photograph of the front and the side of the object are loaded into Blender3D. Using these images as a guide the object can then be modelled to fit the pictures. The only thing to keep in mind is, since the modelling happens in a 3D environment, that each vertex of the model has to fit both of the pictures. Additionally this technique helps greatly in the texturing process. Blender3D allows to project a picture upon a model and then bake this projection into the uv-map. Also a combination of projections is possible. Unfortunately the border at which the two images are merged together is clearly visible on the final uv-map, and has to be processed in a image processing software as a final step. All the smaller objects, like bags or magazines, were modelled using only a single picture as a reference and as texture input. A single rig was created for all the human models, and the animations were created in a way that they are all based on a base pose. This base pose is important for the switching between poses, since it is the only one that has a seamless transition into the different poses. So to change from pose A to pose B, the avatar hast to change from pose A to the base pose, and from there then into pose B. The facial animations were created using shape keys, which allow to alter all the vertices of a model and save these deformations in relation to a base position. In case of the faces the

Psychological Experiments

Two psychological studies were conducted on public speaking anxiety using the above described virtual lecture hall. The objective of the first study was the comparison of two groups holding a presentation either in front of a virtual audience (experimental group) or an imagined audience (control group). The groups were evaluated with regards to their social insecurity as a speaker, reported anxiety and physiological arousal as well as the perceived reality experience of the virtual and the imagined environment. The second study investigated predictors of the perceived usefulness of the virtual public speaking scenario in a larger sample. Both of the studies were conducted at the Department of Psychology at the University of Vienna in accordance with the current version of the Declaration of Helsinki. Prior to participation all participants signed an informed consent form indicating the experiments procedure and the possibility to terminate participation at any time. All statistical analyses were conducted using SPSS Version 15 (SPSS, Inc. Chicago, USA) considering an alpha error of 5%.

Study 1

Participants The overall sample (N = 50) consisted of students who were recruited from several courses at the University of Vienna and received a course credit for their participation. The mean age of the virtual group (N = 25) was 23.44 years (SD = 3.355) ranging from 20 to 35 years. Eight percent were male (N = 2). The mean age of the control sample was 24.84 years (SD = 3.023). In this group the percentage of males was a little higher with an overall of N=8 males (32.0%).

Procedure Upon arrival to the lab, participants were randomly assigned to either the control group or the experimental group and instructed to hold a 5 minute presentation after a 10 minute preparation period. All participants were given a printed version of the 20 slide presentation to get acquainted with it. In order to ensure the novelty of the subject across participants, a fairly unfamiliar theme was chosen: the description of the kingdom of Bhutan. After preparation, the experimental group was presented with the virtual lecture hall using a head mounted display (eMagin Z800 3D, Bellevue, Washington). A standardized protocol was used for the lecture hall resulting in an overall audience of 20 viewers (both male and female) among which 2 characters were bored and seemed to be asleep on the desks and 2 were laughing out loud once during the presentation. Furthermore, half of the remaining audience was showing neutral emotions. The slides were presented in the virtual environment and controlled by the presenting participant, who -like the participant's virtual self -was standing up during the presentation period. In contrast to the experimental group presenting in the virtual environment the controls were asked to merely imagine an audience. The participants were instructed to stand up in front of a small computer screen containing the presentation slides and speak out loud while imagining a lecture hall around them. To facilitate the imagination of the audience, a short imagination exercise was conducted prior to the start of the procedure.

Measures Table 1 provides an overview over all psychological questionnaires used in study 1 and 2. The two-factor solution of the questionnaire Personal Report of Confidence as a Speaker (PRCS) [START_REF] Hook | A short-form of the Personal Report of Confidence as a Speaker[END_REF], was used to assess the participants social insecurity (6 items) and anxiety (12 items) during the public speaking task on a 4 point Likert scale. The participant was asked to rate statements on a 4 point Likert scale (does apply -does not apply). Trait social anxiety was measured by the 20-item version of the Social Interaction Anxiety Scale (SIAS) [START_REF] Mattick | Development and validation of measures of social phobia scrutiny fear and social interaction anxiety[END_REF] on a 5 point Likert scale (not at all -extremly). Additionally, a single 4point-Likert-scaled item (strongly agree -strongly disagree), from the iGroup Presence Questionnaire, IPQ [START_REF] Schubert | The experience of presence: Factor analytic insights[END_REF], was used to measure the perceived reality of the virtual and the imagined environment. To measure stress related sympathetic activity the participants heart rate during the speech was recorded using M-EXG (Schuhfried BFB 2000 x-pert, Moedling, Austria). EKG was assessed using three one-way electrodes (3M Medica RedDot electrodes, Perchtoldsdorf, Austria). Heart rate was monitored at 5s intervals throughout the speech; 60s intervals were computed using the Schuhfried BFB 2000 x-pert software for analysis. Results Neither heart rate, measured in a 60s interval previous to the task, (t(48) = 1.589, p = 0.119) nor trait social anxiety measured by SIAS (t(48) = 1.442, p = 0.156) did differ at baseline level.

Psychological questionnaires: In order to estimate whether the two groups showed any differences on the measures of social insecurity and anxiety during the public speaking task and perceived reality group comparisons using t-tests were conducted. Figure 3 shows the different distributions between groups on the PRCS scales and the perceived reality (means±SEM). The group presenting in front of the virtual audience differed significantly (t(48) = 2.759, p = .008) from the group imagining the scenario, in sum reporting a higher perceived realness of the situation (experimental: M = 4.64, SD = 1.380; control: M = 3.56, SD = 1.386). Additionally, the virtual group (M = 27.56, SD = 6.980) showed higher levels of reported anxiety than the control group (M = 21.72, SD = 6.509) (t(48) = 3.590, p = 0.004) and at the same time, the experimental group (M = 18.76, SD = 4.064) reported significantly higher levels of social insecurity than the control group (M = 15.32, SD = 4.028) (t(48) = 3.006, p = 0.004).

Physiological Measures: A repeated measures ANOVA comparing the two groups was employed. Additionally, a Greenhouse-Geisser adjustment was used to correct the violation of the sphericity assumption ( = 0.48). Heart rate interval analysis indicates a significant main effect of time (F (2.392, 114.819) = 77.007, p < 0.001), a significant difference between the groups (F (1, 48) = 7.110, p < 0.010) and an interaction effect time x group (F (1.617, 114.819) = 6.547, p < 0.001). While both groups showed a higher heart rate (more physiological arousal) at the beginning of the speech it symmetrically declined for both groups during the speech. Yet, the virtual group showed an a priori higher heart rate than the control group, in sum indicating higher physiological stress and anxiety during the virtual exposition (p < 0.001). Figure 4 depicts the heart rate means (±SEM) according to the 60s intervals over the 5 minute speaking period.

Study 2

Participants The sample consisted of N = 137 Psychology students recruited from several courses at the University of Vienna. The mean age was 24.18 years (SD= 3.565) ranging from 20 to 40 years. Approximately fifteen percent of the sample were males (N = 20) whereas the majority consisted of female students (N = 117, 85.4%). Most of the participants (N = 109) stated to have a lot of experience with public speaking (>5 presentations). Nineteen participants reported fair experience (4-5 presentations) and only nine persons had little experience (1-3 presentations). The majority (N = 123) of the sample was right handed (only N = 14 were left-handed). 133 participants were analyzed, 4 datasets were excluded because of missing values.

Procedure The procedure was the same as for the experimental group in study 1 including the same instructions, the same subject and length of presentation and the same settings of the virtual lecture hall. Again, the virtual environment was presented using a head mounted display (eMagin Z800 3D, Bellevue, Washington) and the participant was standing up while presenting. Measures In addition to the PRCS (described in study 1 above) a German version of the NEO-Five-Factor-Inventory (NEO-FFI) [START_REF] Costa | Revised NEO Personality Inventory (NEO-PI-R) and NEO Five-Factor Inventory (NEOFFI) professional manual[END_REF], was used in the second study (see table 1 for item wording). The 60-item NEO-FFI assesses 5 personality factors known as the Big Five on a 5 point Likert scale (strongly agree -strongly disagree). Furthermore, a self-constructed 12-item scale regarding the attitude towards technology (see Technology Acceptance Model, TAM) [START_REF] Davis | Perceived usefulness, perceived ease of use, and user acceptance of information technology[END_REF] was applied. It consists of 3 scales assessing curiosity towards technology use, usability of the technology and perceived usefulness of the technology on a 7 point Likert scale (essential -unessential).

Results

The perceived usefulness of the virtual lecture hall was rated by the participants after the exposition with the protocol. According to the average ratings over the 4 items 56% of the participants rated the system as useful or higher (28% rated the system as very useful or essential. In contrast, 21% rated the system as unessential, very useless, or useless, while 23% rated the system as neither useful nor useless. A multiple linear regression analysis was conducted to identify the best predictors of the technology's perceived usefulness. Both, the five personality factors (personality facets) and the two subscales of the technology facets curiosity and usability were entered as predictors in the regression model, additionally the variable social insecurity as speaker was included into the analysis.

The current results indicate that the participants' social insecurity as speaker during the speech and both technology facets (usability and curiosity) were encouraging predictors of the dependent variable. Assuming a higher alpha level at 0.10, two personality facets (extraversion and conscientiousness) would have shown a predictive value as well. Table 2 reports the standardized coefficient, tcoefficient and significance level for each independent variable. Nevertheless, the usability of the system seems to predict the usefulness of the virtual lecture hall best, followed by the person curiosity towards technology use and high values of social insecurity. In sum, predictor variables included in the final regression model accounted for almost 31% of the variance (R 2 = 0.35; adj. R 2 = 0.31; F (9, 124) = 8.460, p < 0.000; Durbin-Watson= 1.756).

Conclusions

Results from Study 1 offer encouraging evidence that in comparison with the control group, which was asked to imagine the audience, the virtual lecturing scenario tends to decrease the participants' self-confidence as speaker and evoke insecurity as well as self-reported anxiety during the speech task. Also, the virtual group showed a significantly higher increase in heart rate (a psychophysiological indicator of stress and arousal) than the control group. These observations indicate the efficacy of the virtual lecture hall as a means for virtual exposition therapy. Additionally, participants of the virtual group had higher ratings than their controls when asked about the perceived level of realness of the lecture hall. In accordance to our findings, previous studies indicate that stronger feelings of actually being present in the virtual environment both positively alter the perception of its realness and vividness and evoke behavioral and psychophysiological reactions that are similar to those in a comparable real life situation. Thus, the more a person who is immersed in a virtual environment behaves like in a comparable real environment, the better the transfer of knowledge and learned skills will be. It therefore seems crucial to develop virtual scenarios with the best possible stimulating and rich content in order to enhance presence and therein increase the efficacy of the training tool. As demonstrated in the current study, a virtual lecturing scenario may indeed evoke satisfying emotional and psychophysiological reactions in order to be effectively used to train public speaking competencies.

In Study 2 curious and socially insecure persons were identified to rate the virtual lecture hall as more useful. We assume that these findings are a result of the participants' individually different motivations to use the technology. Thus, future research should take individual differences in terms of motive and motivation into account. Moreover, participants perceiving the system as usable and easy to use reported higher perceived usefulness of the virtual lecture hall; this result is consistent with Davis' technology acceptance model (1989), which indicates a strong causal relationship between the usability and the perceived usefulness of a technology or a technological system. Thus, if such virtual reality tools shall be designed for use in therapy and treatment a great focus should be put on their ease of use, including both, the programming of the virtual simulation and the application of immersive technologies such as head mounted displays. The user's satisfaction with an easy to use navigation through the virtual environment and a highly effective head tracking system may lead to a higher acceptance of the system and thus, enhance motivation to use it again. Also, if the user identifies a system as useful, he may be more prone to engage in it and develop a sufficient level of presence for the VR to be effective (see above).

Regarding personality facets, extraverted persons seem to rate the virtual technology as more useful than introverted persons, possibly reflecting the generally more positive attitude of extraverted persons towards new (social) experiences such as the experimental situation in general. In contrast, conscientious persons showed a negative trend in rating the technology as useful. The high achievement standards of the highly conscientious participants might have been counteracting with the satisfaction of their virtual presentation and hence, with the positive ratings of the technology altogether. These results are highly valuable, since they indicate that not all users may equally engage in and thus, benefit from these virtual scenarios. Yet, more research is needed if these findings shall effectively be used to identify a person to be unsuitable for a VR treatment or let alone to establish ideal user types for VR scenarios. In future, interdisciplinary approaches covering both, the development of the technologies and the area of their application are called upon extending their collaborations in order to study such phenomena more broadly.

Fig. 1 .

 1 Fig. 1. 70 avatars with fill sprites.

Fig. 3 .

 3 Fig.3. Differences between the virtual and the control group in perceived reality, social insecurity and anxiety (means± SEM).

Fig. 4 .

 4 Fig.4. Group differences between heart rates during a 5 minute speaking period (means±SEM).

Table 1 .

 1 Psychological assessments.

		Factor	Description	Example for item wording
	Personality facets	Neuroticism	anxiety, depression, self-consciousness and vulnerability to stress	I am easily concerned.
		Extraversion	assertiveness, activity and excitement seeking	I am a very active person.
		Openness for experience	fantasy and ideas	I often try new and foreign dishes.
		Conscientiousness competence, order and self-discipline I work hard to reach my goals.
		Agreeableness	altruism, compliance and modesty	I always try to act considerate and sensible.
	Technology facets	Curiosity	inquisitive thinking about technology and the desire to explore new technological tools and devices	I was curious to use computer based applications like the VR.
		Usability	comfort and effortlessness of the technology usage	It was easy to transfer what I intended to do into the VR.
		Perceived Usefulness	enhancement of performance or well-being caused by the usage of the technology	Computer based applications like the VR constitute a good preparation for a speech.
	State facets	Social Insecurity	competence in social situations (inverse items)	I look forward to an apportunity to speak in public.
		Anxiety	apprehension when the subject is faced with the audience	My hands tremble when I try to handle objects on the platform.
		Realness	experience of realism in the virtual world	Do you experience the audience as real?
	Trait facets	Social Anxiety	insecurity and anxiety in social situations	I am nervous mixing with people I don't know well.

Table 2 .

 2 Linear Regression analysis to predict perceived usefulness.

			Beta	t	p
		Neuroticism	0.032	0.367	0.715
	Personality facets	Extraversion Openness for experience -0.041 0.144 Agreeableness 0.106	1.805 -0.517 1.366	0.073* 0.606 0.175
		Conscientiousness	-0.145	-1.860	0.065*
	Technology	Curiosity	0.297	3.872	0.000**
	facets	Usability	0.408	5.095	0.000**
	State facets	Social insecurity	0.245	2.817	0.006**
	Notes: Dependent variable: Perceived Usefulness; * p< 0.10, **p<0.05

http://sparx.org.nz for

http://www.virtuallybetter.com/

http://www.vrphobia.com/therapy.htm

Acknowledgments

We would like to thank Jasmine Gomm, Nathalie Hauk, Anna Hoffmann, Elisabeth Kastenhofer, MSc., Nora Poesl and Janka Scharfenberger for helping us with the acquisition of the data.


Letizia Jaccheri
email: letizia@idi.ntnu.no

Michail N Giannakos

Open Source Software for Entertainment

Keywords: Open Source Software, Art, Creative processes, Arduino, Scratch, Processing, Maker communities

Introduction

Tools for creativity enable digital creators, professionals or hobbyists, to realize their desire for expression with powerful development environments that support animation, music, or video editing tools [START_REF] Shneiderman | Creativity Support Tools Accelerating Discovery and Innovation[END_REF]. Open source tools for creativity, such as Processing (http://processing.org), Arduino (http://arduino.cc) [START_REF] Buechley | LilyPad in the wild: how hardware's long tail is supporting new engineering and design communities[END_REF], and Scratch (http://scratch.mit.edu) [START_REF] Resnick | Scratch: programming for all[END_REF] have their roots in this inter-section of open source software (OSS) and creativity. These two fields of study and practice are important for the work presented in this tutorial. The aim of the tutorial is to stimulate participants to acquire knowledge and basic skills about creative, playful and open software engineering practices and tools. The goal of the tutorial is to disseminate knowledge on existing open software tools and community projects practices as well as facilitating simple practical activities with the purpose of stimulate reflection.

A software system is open source if its code is available to everybody for inspection, use, and modification. Users of OSS are not paying customers but potential software co-developers. OSS was born as a movement based on contributions of volunteers. However, an increasing number of companies are getting involved in OSS projects [START_REF] Ayala | Five facts on the adoption of open source software[END_REF]. Use and further release of modified version of an OSS system are regulated by a license. OSS is much more than the possibility to change the code. The most important characteristics and success factor of OSS projects are associated with communities of users and developers. The degree of activeness of the community is crucial for an OSS project. Each user of an active community is not isolated but part of a community. Members of each community are connected and help each other via mailing lists, forum and IRC channels.

Joy of creation as entertainment

The role of the active user in entertainment has been explored in the entertainment computing literature. Nakatsu et al. [START_REF] Nakatsu | A New Framework for Entertainment Computing: From Passive to Active Experience[END_REF] presents a framework for understanding entertainment which divide experiences in passive (like reading and watching movies) and active (like doing sports and creating art). The inner joy of creation and unselfish cooperation has often been identified as an important asset of the OSS developer culture. Around these issues of creation and cooperation, Castells [START_REF] Castells | The Internet Galaxy: Reactions on the Internet[END_REF] proposes analogies between the world of OSS and the world of art. Castells anticipates art as a growing area of the Internet, stating that 'open source art is the new frontier of artistic creation'. The Internet not only serves as a means for distribution of artifacts, but also serves as a shared platform for a process that aims to create new artistic artifacts. Several difficulties have been faced into the collaboration between distant persons. This is an issue shared with most intellectual activities. In previous work [START_REF] Trifonova | SArt: Towards innovation at the intersection of software engineering and art[END_REF] this issue has been identified, when computer engineering students are working together with nonengineers or other branches of engineering. Applying and adapting methods from the field of social psychology have proven to be successful in optimizing the collaboration in heterogeneous groups. These methods approach the issues in a social manner and generally aim at optimizing the social issues and in effect optimizing the end results of the collaboration. This has proven successful when applied on students with a multi-disciplinary background working with innovative, new media, solutions. Innovative and creative businesses are often found within the field of computer science. These are often faced with similar issues, for instance when one or more stakeholders to a project have different backgrounds than the rest of a team. Or when the task is to "think outside the box" and develop creative solutions. The social issues experienced in these settings may be an obstacle that results in sub optimal solutions.

Description of the Tutorial

This tutorial builds on our experience in facilitating and studying creative processes.

[4] [START_REF] Høiseth | Art and technology for young creators[END_REF] and focus on OSS and its intersection with entertainment.

Audience:

The audience for this tutorial comprises software engineers, researchers and PhD students interested in creative technologies and processes. The participants will have to bring their own laptop (Windows, Linux, or Mac). It is an advantage if the participants have already installed Processing and Scratch tools, but this is not mandatory. No practical programming knowledge is required. Participants will be able to work in small groups to be able to test and experience the methods presented in the tutorial. The organizers will exploit their networks to improve recruiting to this tutorial.

Inspirational Questions:

The tutorial is motivated by several inspirational research questions that are intended to be explored and be a basis for reaction. Examples of questions are: RQ1. Which is the relationship between OSS and entertainment computing? RQ2. How can an understanding of OSS communities enhance state of the art in entertainment computing?

Tutor Background: Jaccheri is a professor at NTNU, Norway. She has twenty years' experience of teaching and researching and she has been involved in the supervision of more than 12 PhD students. She has published book chapters and papers and has given presentations at several universities in Europe. Her motivation for developing this tutorial is to disseminate the bulk of knowledge and practical learning methods with an International audience. Preliminary versions of this tutorial have been tested with University students and in related tutorials [START_REF] Castells | The Internet Galaxy: Reactions on the Internet[END_REF].

Structure:

The format is a full day tutorial. A preliminary structure of the tutorial is available at http://artentnu.wordpress.com/icec2011-tutorial/ together with all the slides, which can be downloaded and reused. See also Table 1. The first half of the tutorial will include presentations on the background of the topics included, different tools that leans well to OSS and art, several different strategies for enhancing creative collaboration in teams and an array of examples illustrating the potential in the intersection of OSS and art. The second half of the tutorial will include experience and creativity based learning sessions. The participants will work in teams on small creative tasks using the methods presented earlier. Several work sessions will be held with a reaction and discussion part at the end of each. This will introduce the participants to some of the obstacles that can occur when working in a creative team and several of the strategies that can either avoid or address these issues.

Table 1 .

 1 Structure of the day Final discussion and conclusions Breaks are from 10:00 -10:30 and 15:30 -16:00; Lunch is 12:00 -14:00

	Time	Activity
	09:15 -10:00	Computer art and entertainment
	10:30 -11:15	Open source software
	11:15 -12:00	OSS, art and entertainment
	14:00 -15:30	Creative session 1: (a) Choose characters; (b)
		Experiment with motion, looks, sound, sensors
		(Pico Boards will be provided by the organizers).
	16:00 -17:15	Creative session 2: (c) Develop a story board;
		(d) Programming, (e) Share.
		17:15


Madeleine Baalsrud Jannicke

Heiko Hauge

Minhua Duin

Manuel Ma
email: m.ma@gsa.ac.uk

Oliveira

Duin

Jannicke Baalsrud Hauge

Heiko Duin

Minhua Ma

Manuel Oliveira
email: manuel.oliveira@sintef.no

SGDA2012

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

International Conference on Serious Games Development and Applications

The Third International Conference on Serious Games Development and Applications is this year organised as a satellite conference to IFIP-ICEC2012 in Bremen. SGDA 2012 appears in the sequence of the successes of the First International Workshop on Serious Games Development and Application held in Derby in 2010 and Second International Conference on Serious Games Development and Applications, held in Lisbon in 2011. The aim of SGDA is to collect and disseminate knowledge on serious games technologies, design and development; to provide practitioners and interdisciplinary communities with a peer-reviewed forum to discuss the state-of-theart in serious games research, their ideas and theories, and innovative applications of serious games; to explain cultural, social and scientific phenomena by means of serious games; to concentrate on the interaction between theory and application; to share best practice and lessons learnt; to develop new methodologies in various application domains using games technologies; and to explore perspectives of future developments and innovative applications relevant to serious games and related areas.

The emergence of serious games as a branch of video games has introduced the concept of games designed for a serious purpose other than pure entertainment. To date the major applications of serious games include engineering, education, health care, military applications, city planning, production, crisis response, and training. Serious games have primarily been used as a tool that gives players a novel way to interact with games in order to promote physical activities, to learn skills and knowledge, to support social-emotional development, to facilitate behavior transformation, to treat different types of psychological and physical disorders, etc. Many recent studies have identified the benefits of using video games in a variety of serious purposes. However, most Serious Games are still mostly focusing on the learning objective, and not so much in developing engaging and motivating user interfaces. In the world of entertainment games, there has been much more focus on the user experience. Therefore the organizational committee decided to co-locate SGDA with the 11th International Conference on Entertainment Computer conference. This will give the opportunity of fostering the dialogue between the entertainment and serious games communities and will support a bi-directional knowledge transfer.

At SGDA 2012 around 20 presentations will be hold on different aspects of serious games design and use. The papers are published in LNCS. We are all welcoming you to participate in our discussions.

  The Conference is supported by the GALA Network of Excellence for Serious Games, the TARGET (Transformative, Adaptive, Responsive and enGaging En-vironmenT) Project which is a Large-scale Integrating Project funded by the European Community under the FP7 (ICT-2007.4.3) and Digital Libraries & Technology-Enhanced Learning 2009-2011 (Grant Agreement N° 231717), BIBA -Bremer Institut für Produktion und Logistik GmbH, University of Bremen, Glasgow School of Art, INESC-ID, Technical University of Lisbon, and University of Derby.