Memory and Cognition Laboratory

This paper focuses on recognizing and understanding social dimensions (the personality traits and social impressions) during small group interactions. We extract a set of audio and visual features, which are divided into three categories: intra-personal features (i.e. related to only one participant), dyadic features (i.e. related to a pair of participants) and one vs all features (i.e. related to one participant versus the other members of the group). First, we predict the personality traits (PT) and social impressions (SI) by using these three feature categories. Then, we analyse the interplay be- tween groups of features and the personality traits/social impressions of the interacting participants. The prediction is done by using Support Vector Machine and Ridge Regression which allows to determine the most dominant features for each social dimension. Our experiments show that the combination of intra-personal and one vs all features can greatly improve the prediction accuracy of personality traits and social impressions. Prediction accuracy reaches 81.37% for the social impression named ’Rank of Dominance’. Finally, we draw some interesting conclusions about the relationship between personality traits/social impressions and social features.

The evolving small-cell (originally femtocell) networks are envisioned to provide improved capacity and coverage in next generation cellular systems. Small-cell deployments pose many challenges among which radio resource management (i.e., interference management, resource allocation, and power control) is the most significant one. The aim of this talk is to provide an overview of the radio resource management problem in small-cell networks considering OFDMA (e.g., LTE, WiMAX) femtocells, and the ongoing research on this topic. After a brief overview of the small-cell networks, we outline the major challenges in successful deployment of small-cells in next generation cellular wireless systems. In particular, the challenges related to resource allocation, co-tier/cross-tier interference management and power control are discussed. Then we provide a comprehensive overview of the different proposed techniques for resource allocation and interference management in small-cell networks. In this context, two different approaches are described: one based on clustering and semi-centralized computations, and one based on cooperative game theory. The requirements for strategic interference management via power control and resource allocation mechanisms are then discussed.

The growing complexity of processes whatever their kind (i.e. business, software, medical, military) stimulates the adoption of process execution, analysis and verification techniques. However, such techniques cannot be accurately validated as it is not possible to obtain numerous and realistic process models in order to stress test them. The small set of samples and ``toy'' models publically available in the literature is usually insufficient to conduct serious empirical studies and thus, to validate thoroughly work around process analysis and verification. In this paper, we face this problem by proposing a process model generator using a multi-objective genetic algorithm. The originality of our approach comes from the fact that process models are built through a sequence of high-level operations inspired by the way a process modeler could have actually performed to model a process. A working generator prototype has been implemented and shows that it is possible to quickly generate huge, syntactically sound and user-tailored process models.

Body-tilt effect on the haptic discrimination of orientations and the 'oblique effect' (better discrimination of the vertical orientation than of an oblique orientation) were examined in 5-month-old infants. Body tilt leads to a mismatch between egocentric and gravitational reference frames and indicates in which reference frame orientations and oblique effect are defined. A familiarization/reaction to novelty procedure was used in upright body and tilted body conditions. Results revealed the occurrence of a haptic oblique effect in the upright body position, which disappeared when the body was tilted. The results suggest that spatial orientations and the oblique effect depend on a mixed reference frame that integrates not only gravitational information but also egocentric information.