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A novel laser-optical fiber Bragg grating anemometer (FBGA) has been devised for measuring the speed of a moving gas in the range 0-1.5 m s(-1). As a test, the FBGA was applied to measuring the speed of the electric wind generated in the particularly harsh, high-voltage environment of a dc, negative-polarity, partial (corona) discharge in atmospheric air. The instrument proved more stable and yielded an order-of-magnitude improvement in sensitivity (deltav approximately 4 x 10(-3) ms(-1)) compared with other optical-fiber-based anemometers. On-axis wind speeds ranging from zero to 1.1 m s(-1) were measured in the vicinity of the corona discharge.

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An active tendon control system for civil engineering cable‐supported structures is proposed. The technique is based on a tendon actuator collocated with a force sensor. A large‐scale mock‐up using industrial components has been built and widely tested. The test‐bed is a model of cable‐stayed bridge during its construction phase, equipped with hydraulic actuators on the two longest stay‐cables. The results of several damping experiences are presented; they clearly demonstrate the efficiency of the active damping system. The proposed technology is directly applicable to real structures by scaling up the devices.

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