During the use of Advanced Driver Assistance Systems (ADAS), drivers can intervene in the active function and take back control due to various reasons. However, the specific reasons for driver-initiated takeovers in naturalistic driving are still not well understood. In order to get more information on the reasons behind these takeovers, a test group study was conducted. There, 17 participants used a predictive longitudinal driving function for their daily commutes and annotated the reasons for their takeovers during active function use. In this paper, the recorded takeovers are analyzed and the different reasons for them are highlighted. The results show that the reasons can be divided into three main categories. The most common category consists of takeovers which aim to adjust the behavior of the ADAS within its Operational Design Domain (ODD) in order to better match the drivers’ personal preferences. Other reasons include takeovers due to leaving the ADAS’s ODD and corrections of incorrect sensing state information. Using the questionnaire results of the test group study, it was found that the number and frequency of takeovers especially within the ADAS’s ODD have a significant negative impact on driver satisfaction. Therefore, the driver satisfaction with the ADAS could be increased by adapting its behavior to the drivers’ wishes and thereby lowering the number of takeovers within the ODD. The information contained in the takeover behavior of the drivers could be used as feedback for the ADAS. Finally, it is shown that there are considerable differences in the takeover behavior of different drivers, which shows a need for ADAS individualization.

Spectrum sensing plays a key role for radio resource awareness in cognitive radio. To enhance the capabilities of cognitive radio nodes, exploiting the spatial resource in addition to frequency and time resources seems reasonable. In this paper we investigate the impact of using the spatial information from a sector antenna on sensing reliability as well as on availability of opportunity for secondary communication in cognitive radio. A ray tracer is used for modeling the urban environment and for wave propagation simulation. The power angular profiles obtained at different locations are further processed with MATLAB using measured and analytical radiation beam patterns to evaluate opportunity and detection performance. The measured beam patterns are obtained from a sector antenna specifically devised for exploiting spatial resources, whereas the analytical patterns are obtained from mathematical expressions representing three dipole elements in a circular array. The performance is compared to that obtained with an omni-directional antenna. The results show that exploiting the spatial dimension in spectrum sensing in cognitive radio improves the performance in terms of increased opportunities for secondary communications as well as the better detection of primary signals.

The lack of publicly available annotated databases is one of the major barriers to research advances on emotional information processing. In this contribution we present a recently collected database of spontaneous emotional speech in German which is being made available to the research community. The database consists of 12 hours of audio-visual recordings of the German TV talk show ldquoVera am Mittagrdquo, segmented into broadcasts, dialogue acts and utterances. This corpus contains spontaneous and very emotional speech recorded from unscripted, authentic discussions between the guests of the talk show. In addition to the audio-visual data and the segmented utterances we provide emotion labels for a great part of the data. The emotion labels are given on a continuous valued scale for three emotion primitives: valence, activation and dominance, using a large number of human evaluators. Such data is of great interest to all research groups working on spontaneous speech analysis, emotion recognition in both speech and facial expression, natural language understanding, and robust speech recognition.

We present novel methods for estimating spontaneously expressed emotions in speech. Three continuous-valued emotion primitives are used to describe emotions, namely valence, activation, and dominance. For the estimation of these primitives, support vector machines (SVMs) are used in their application for regression (support vector regression, SVR). Feature selection and parameter optimization are studied. The data was recorded from 47 speakers in a German talk-show on TV. The results were compared to a rule-based fuzzy logic classifier and a fuzzy k-nearest neighbor classifier. SVR was found to give the best results and to be suited well for emotion estimation yielding small classification errors and high correlation between estimates and reference.

Rigid head motion is a gesture that conveys important nonverbal information in human communication, and hence it needs to be appropriately modeled and included in realistic facial animations to effectively mimic human behaviors. In this paper, head motion sequences in expressive facial animations are analyzed in terms of their naturalness and emotional salience in perception. Statistical measures are derived from an audiovisual database, comprising synchronized facial gestures and speech, which revealed characteristic patterns in emotional head motion sequences. Head motion patterns with neutral speech significantly differ from head motion patterns with emotional speech in motion activation, range, and velocity. The results show that head motion provides discriminating information about emotional categories. An approach to synthesize emotional head motion sequences driven by prosodic features is presented, expanding upon our previous framework on head motion synthesis. This method naturally models the specific temporal dynamics of emotional head motion sequences by building hidden Markov models for each emotional category (sadness, happiness, anger, and neutral state). Human raters were asked to assess the naturalness and the emotional content of the facial animations. On average, the synthesized head motion sequences were perceived even more natural than the original head motion sequences. The results also show that head motion modifies the emotional perception of the facial animation especially in the valence and activation domain. These results suggest that appropriate head motion not only significantly improves the naturalness of the animation but can also be used to enhance the emotional content of the animation to effectively engage the users