The Effect of High-Frequency Parametric Excitation on a Stochastically Driven Pantograph-Catenary System

<table>Joint stationary probability density <svg height="16.5625" id="M180" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 48.174999 16.5625" width="48.174999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>. (a): No fast excitation; (b) <svg height="18.362499" id="M181" style="vertical-align:-5.76988pt" version="1.1" viewbox="0 0 89.400002 18.362499" width="89.400002" 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,-.012,10.8,15.188)"><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><g transform="matrix(.012,-0,0,-.012,16.511,15.188)"><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>
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</svg>.</table>

Shock and Vibration

fig8

Figure 8

Figure 8: The Effect of High-Frequency Parametric Excitation on a Stochastically Driven Pantograph-Catenary System 