J
Johannes Oeffner
Researcher at National Institute of Water and Atmospheric Research
Publications - 9
Citations - 549
Johannes Oeffner is an academic researcher from National Institute of Water and Atmospheric Research. The author has contributed to research in topics: Whiskers & Engineering. The author has an hindex of 5, co-authored 7 publications receiving 454 citations. Previous affiliations of Johannes Oeffner include Harvard University & University of Rostock.
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Journal ArticleDOI
The hydrodynamic function of shark skin and two biomimetic applications
TL;DR: Digital particle image velocimetry of the flow field surrounding moving shark skin foils shows that skin denticles promote enhanced leading-edge suction, which might have contributed to the observed increase in swimming speed and might thus enhance thrust, as well as reduce drag.
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Harbor seal vibrissa morphology suppresses vortex-induced vibrations.
Wolf Hanke,Matthias Witte,Lars Miersch,Martin Brede,Johannes Oeffner,Mark Michael,Frederike D. Hanke,Alfred Leder,Guido Dehnhardt +8 more
TL;DR: Using force measurements, flow measurements and numerical simulations, it is found that the dynamic forces on harbor seal whiskers are, by at least an order of magnitude, lower than those on sea lion whiskers, which do not share the undulated structure.
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Flow sensing by pinniped whiskers
Lars Miersch,Wolf Hanke,Sven Wieskotten,Frederike D. Hanke,Johannes Oeffner,Alfred Leder,Martin Brede,Matthias Witte,Guido Dehnhardt +8 more
TL;DR: Measurements revealed that both whisker types were able to detect the vortex shedding frequency but differed considerably with respect to the signal-to-noise ratio (SNR), and revealed that in sea lion whiskers, each noise signal contained a dominant frequency suggested to function as a characteristic carrier signal.
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Species composition and acoustic signatures of mesopelagic organisms in a subtropical convergence zone, the New Zealand Chatham Rise
TL;DR: Seven fish assemblages were distinguished based on their unique acoustic mark characteristics (amplitude and dimension features of the volume backscatter), vertical distribution and ancillary information, and classification results were synthesised in a decision model.
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In situ target strength estimates of optically verified southern blue whiting (Micromesistius australis)
TL;DR: In this paper, the acoustic target strength (TS) of southern blue whiting (Micromesistius australis) at 38 kHz was obtained using an autonomous acoustic-optical system (AOS) mounted on a demersal trawl.