Our goal was to examine the propulsion mechanism of sculling motion by visualising the unsteady flow field around a swimmer's hand using PIV. One formerly competitive swimmer participated in this study and was instructed to swim using a sculling motion in a swimming flume. Two-hundred series of sequential flow fields around the swimmer's left hand were simultaneously obtained by PIV. The flow fields were calculated from two sequential particle images to determine the particle velocity-vectors and the intensity of the vortices. A leading edge vortex was found beside the little finger of the hand during the out-scull phase, and the vortex seemed to be shed during the transition phase from out-scull to in-scull. The circulation change around the hand was seen after the transition phase. The results of the present study suggested that the sculling swimmer created a propulsive force induced by the momentum change of the flow field relating to the circulation and the shed vortex.

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A growing number of studies clarify user's behavior on the Web in order to decrease costs of data collection using the web. A purpose of the present study is to obtain additional information from respondent's answers to the web query, by analyzing PC-mouse movements as behavioral information. 612 respondents selected preferred choices from 12 options. The present study attempted to reveal the order of priorities to selected choices. It was clarified that the gaze movement and the PC-mouse movement during the query were agreed well with each other. As a result, our method could predict 39.9% of the order of priorities. Results were never affected by the age and the sex. Required number of respondents to keep the reliability of the prediction was 90 or more.

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