Aimed at long-term monitoring of daily office conversations without recording the conversational content, a system is presented for estimating acoustic nonverbal information such as utterance duration, utterance frequency, and turn-taking. The system combines a sound localization technique based on the sound energy distribution with 16 beam-forming microphone-array modules mounted in the ceiling for reducing the influence of multiple sound reflection. Furthermore, human detection using a wide field of view camera is integrated to the system for more robust speaker estimation. The system estimates the speaker for each utterance and calculates nonverbal information based on it. An evaluation analyzing data collected over ten 12-hour workdays in an office with three assigned workers showed that the system had 72% speech segmentation detection accuracy and 86% speaker identification accuracy when utterances were correctly detected. Even with false voice detection and incorrect speaker identification and even in cases where the participants frequently made noise or where seven participants had gathered together for a discussion, the order of the amount of calculated acoustic nonverbal information uttered by the participants coincided with that based on human-coded acoustic nonverbal information. Continuous analysis of communication dynamics such as dominance and conversation participation roles through nonverbal information will reveal the dynamics of a group. The main contribution of this study is to demonstrate the feasibility of unconstrained long-term monitoring of daily office activity through acoustic nonverbal information.

Various systems that share remote co-worker's awareness information have been proposed for realizing efficient collaborative work among distributed offices. In this study, we implemented an interruptibility sharing system in a university laboratory and assessed the observation behavior for the displayed information. Observation behavior for each target member was detected using an eye tracker to discuss the usage and effect of the system in a quantitative manner, along with the considerations of workers' job positions and relationships. The results suggested that participants observed interruptibility information approximately once an hour while at their desks. Observations were frequent during break-times rather than when the participants wanted to communicate with others. The most frequently observed targets were the participants themselves. The participants gazed the laboratory members not only in a close work relationship but also in a weak relationship. Results suggested that sharing of interruptibility information assists worker's self-reflection and contributes to the establishment of horizontal connection in an organization including members in weak work relationship.