Search

To implement the concept of a smart structure, a smart active control system is presented. Both fiber Bragg grating (FBG) sensors and neural networks are utilized to construct a system similar to the human being. The smart system is comprised of three parts: a structural condition surveillance system, three converters, and a controller. By distributing as many sensors as possible in the key areas in buildings, FBG sensors can be used for assessing structure soundness while acting as dendrites in a neural network system. Comparison of structural responses under an uncontrolled system, traditional optimal linear quadratic gain, and the proposed NEURO-FBG control system verifies the advantages of using this novel technique approach. The system robustness is evaluated under both time delay and disconnection problems. Analytical results demonstrate that the NEURO-FBG system can effectively control the response of the structure and provide a more reliable system than ordinary active control. DOI: 10.1061/(ASCE)0733-9445(2006)132:8(1293) CE Database subject headings: Structural control; Fiber optics; Neural networks; Earthquake engineering; Sensors.

Experimental results for a full-scale steel frame structure with a smart active control system under shaking-table testing are presented. To this end, a full-scale steel frame structure with the proposed control system is examined under earthquakes simulated by a 5 m x 5 m shaking table with several representative earthquakes arranged to assess the performance and robustness of the proposed control system. Signals detected from fiber Bragg grating sensors showed superior performance to conventional strain gauges in structure surveillance. Experimental data recorded during earthquake excitation, for structural strain, also demonstrated the improved performance of the proposed control system over the traditional active control. Experimental results demonstrated that the control system can be applied to buildings after the whole testing process. DOI: 10.1061/(ASCE)0733-9445(2006)132:8(1304) CE Database subject headings: Structural control; Experimentation; Neural networks; Earthquake engineering; Fiber optics; Sensors.

Presents information on a study which investigated the temperature dependence of the current-voltage characteristics of BST ferroelectric thin film capacitors. Applications of ferroelectric thin films; Methodology used in the study; Results.