Über die Durchdringungscurve von Rotationsflächen zweiter Ordnung mit sich schneidenden Axen

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Über Carbamid- und Guanidinderivate der Sulfofettsäuren

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Ueber Diffusion von Arsenik in Gelatine

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Wave-based defect detection and interwire friction modeling for overhead transmission lines

In this study, the feasibility of continuous, online monitoring of power lines using ultrasonic waves is considered. Local and global wave-based approaches for wire break detection in overhead transmission lines are presented. Both methods use a sending/receiving transducer to generate an ultrasonic, longitudinal, elastic wave in the cable. Defects in the cable cause a portion of the incident ultrasonic wave to be reflected back to the transducer, which when received, can be used to identify the presence of the defect. Although the transducers can only be attached to the surface of the cable, subsurface wires can also be interrogated since elastic energy spreads to these wires through friction contact. This study also explores how the elastic energy of a propagating wave becomes distributed among contacting rods via friction contact. This work focuses specifically on a two-rod system in which the wave energy from an excited “active” rod is transmitted to a neighboring “passive” rod through friction contact. An energy-based model is used to approximate the time average elastic wave power in the two rods as a function of propagation distance. Power predictions from the energy-based model compare well with experimental measurements and finite element simulations.     

Verzweigung periodischer Lösungen nichtlinearer Schwingungsgleichungen

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Die erste Resonanzkurve beim Duffingschen Schwingungsproblem

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