This paper presents an intelligent user interface model dedicated to the exploration of complex databases. This model is implemented on a 3D metaphor: a virtual museum. In this metaphor, the database elements are embodied as museum objects. The objects are grouped in rooms according to their semantic properties and relationships and the rooms organization forms the museum. Rooms? organization is not predefined but defined incrementally by taking into account not only the relationships between objects, but also the user's centers of interest. The latter are evaluated in real-time through user interactions within the virtual museum. This interface allows for a personal reading and favors the discovery of unsuspected links between data. In this paper, we present our model's formalization as well as its application to the context of cultural heritage.

The MOCA Project that aims at designing and studying the interaction and relationship between artificial companions and children in everyday life at home activities. Artificial companions are digital embodied entities that can be either robotic or virtual. In this paper, we focus on a single activity, subpart of the whole project: a coaching application that uses two artificial companions to teach the basics of drums to children. One device is a Nao robot, the other is a virtual agent. This application offers a wide variety of interaction situation that will enable us to conduct several experiments. Future directions are discussed, in terms of user-computer interaction and in terms of coaching and e-learning applications.

In this article the role of different categories of postures in the detection, recognition, and interpretation of emotion in contextually rich scenarios, including ironic items, is investigated. Animated scenarios are designed with 3D virtual agents in order to test 3 conditions: In the “still” condition, the narrative content was accompanied by emotional facial expressions without any body movements; in the “idle” condition, emotionally neutral body movements were introduced; and in the “congruent” condition, emotional body postures congruent with the character's facial expressions were displayed. Those conditions were examined by 27 subjects, and their impact on the viewers’ attentional and emotional processes was assessed. The results highlight the importance of the contextual information to emotion recognition and irony interpretation. It is also shown that both idle and emotional postures improve the detection of emotional expressions. Moreover, emotional postures increase the perceived intensity of emotions and the realism of the animations.

This article analyses the issues pertaining to the simulation of joint attention with virtual humans. Gaze represents a powerful communication channel illustrated by the pivotal role of joint attention in social interactions. To our knowledge, there have been only few attempts to simulate gazing patterns associated with joint attention as a mean for developing empathic virtual agents. Eye-tracking technologies now enable creating non-invasive gaze-contingent systems that empower the user with the ability to lead a virtual human's focus of attention in real-time. Although gaze control can be deliberate, most of our visual behaviors in everyday life are not. This article reports empirical data suggesting that users only have partial awareness of controlling gaze-contingent displays. The technical challenges induced by detecting the user's focus of attention in virtual reality are reviewed and several solutions are compared. We designed and tested a platform for creating virtual humans endowed with the ability to follow the user's attention. The article discusses the advantages of simulating joint attention for improving interpersonal skills and user engagement. Joint attention plays a major role in the development of autism. The platform we designed is intended for research and treatment of autism and tests included participants with this disorder.

MACH--My Automated Conversation coacH--is a novel system that provides ubiquitous access to social skills training. The system includes a virtual agent that reads facial expressions, speech, and prosody and responds with verbal and nonverbal behaviors in real time. This paper presents an application of MACH in the context of training for job interviews. During the training, MACH asks interview questions, automatically mimics certain behavior issued by the user, and exhibit appropriate nonverbal behaviors. Following the interaction, MACH provides visual feedback on the user's performance. The development of this application draws on data from 28 interview sessions, involving employment-seeking students and career counselors. The effectiveness of MACH was assessed through a weeklong trial with 90 MIT undergraduates. Students who interacted with MACH were rated by human experts to have improved in overall interview performance, while the ratings of students in control groups did not improve. Post-experiment interviews indicate that participants found the interview experience informative about their behaviors and expressed interest in using MACH in the future.

Exposure to distressing computer-generated stimuli and feedback of physiological changes during exposure have been effective in the treatment of anxiety disorders (e.g., social phobia). Here we studied voluntary facial activations as a method for regulating more spontaneous physiological changes during virtual social stimulation. Twenty-four participants with a low or high level of social anxiety activated either the corrugator supercilii (used in frowning) or the zygomaticus major (used in smiling) facial muscle to keep a female or a male computer character walking towards them. The more socially anxious participants had a higher level of skin conductance throughout the trials as compared to less anxious participants. Within both groups, short-term skin conductance responses were enhanced both during and after facial activations; and corrugator supercilii activations facilitated longer term electrodermal relaxation. Zygomaticus major activations had opposite effects on subjective emotional ratings of the less and the more socially anxious. In sum, voluntary facial activations were effective in regulating emotional arousal during virtual social exposure. Corrugator supercilii activation was found an especially promising method for facilitating autonomic relaxation.

Location-aware ambient environments are relevant in designing interactive virtual characters. However, they raise several questions about spatial behaviors to be displayed by virtual characters, and about the perception of virtual characters by users. We designed a location-aware virtual agent that adapts its spatial behavior to users' and objects' locations during a search task in a smart room. We conducted an experimental evaluation comparing this adaptive agent with an agent that does not perceive nor use the location of users and objects. The location-aware adaptive agent elicited higher levels of perceived presence and perceived adaptivity. Furthermore, performance was less influenced by task difficulty when users interacted with the adaptive agent. Such results can be useful for the design of future location-aware virtual agents.

Bateau Ivre is a project presented on the Seine River to make a large audience aware of the possible developments of Augmented Reality through an artistic installation in a mobile outdoor environment. The installation could be viewed from a ship by a large audience without specific equipment, through nightly video-projection on the River banks. The augmentation of the physical world was implemented through real-time image processing for live special effects such as contouring, particles, or non-realistic rendering. The artistic purpose of the project was to immerge the audience into a non-realistic view of the River banks that would differ from the traditional tourist tours that highlight the main landmarks of Paris classical architecture.