Noninvasive Remote Sensing Techniques for Infrastructures Diagnostics

<table>FFT absolute coefficients relative to the <svg height="11.825" id="M71" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 13.3625 11.825" width="13.3625" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,6.962,11.762)"><path d="M412 140l28 -9q0 -2 -35 -131h-373v23q112 112 161 170q59 70 92 127t33 115q0 63 -31 98t-86 35q-75 0 -137 -93l-22 20l57 81q55 59 135 59q69 0 118.5 -46.5t49.5 -122.5q0 -62 -29.5 -114t-102.5 -130l-141 -149h186q42 0 58.5 10.5t38.5 56.5z" id="x32"></path></g>
</svg> oscillations.</table>

International Journal of Geophysics

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Figure 4

Figure 4: Noninvasive Remote Sensing Techniques for Infrastructures Diagnostics 