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We estimated the damping ratio of a tower-and-conductor system by combining several identification methods to full-scale measurement data which contain many components of close frequencies of the system vibrating under strong winds. Our procedure was able to extract the component of every vibration mode of the tower from a time history of the measurement data and estimated more accurate damping ratios individually. Moreover we discuss the effects of the progressive deformation of a transmission-conductor-plane due to an increase in wind speed on the development of the aerodynamic damping of the tower-and-conductor system using a three-dimensional nonlinear analysis.Keywords: Aerodynamic damping, 3D wind response of a coupled tower-and-conductor system, Normal decomposition method, Multi degrees of freedom random decrement technique We estimated the damping ratio of a tower-and-conductor system by combining several identification methods and full-scale measurement data which contain many components of close frequencies of the system vibrating under strong winds. Our procedure was able to extract the component of every vibration mode of the tower from a time history of the measurement data and estimated more accurate damping ratios individually. Moreover we discussed the effects of the progressive deformation of a transmission-conductor-plane due to an increase in wind speed on the development of the aerodynamic damping of tower-and-conductor system using a three-dimensional nonlinear analysis.

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We present a novel touch-sensing system that detects the skin resistance of a touched finger using a static capacitive touch panel. The employed frequency-scan method enables us to measure skin resistance regardless of touching conditions. The proposed system can create new touch-sensor applications such as multiuser system and bioelectrical sensing.