Audrey Holm

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The aim of this work was to show the applicability of light diffraction tomography on airborne ultrasound in the frequency range 40 kHz-2 MHz. Seven different air-coupled transducers were measured to show the method's performance regarding linearity, absolute pressure measurements, phase measurements, frequency response, S/N ratio and spatial resolution. A(More)
A great deal of research has been done on the diurnal variations in different forms of animal and human activity. The first diurnal variation to be observed was the one in body temperature, and it is the one most widely recognized today. Similar diurnal variations have been observed in a series of other physical processes. Extensive surveys of the(More)
This article describes a light diffraction technique that allows a measurement of ultrasonic pressure and phase in the cross-section of an ultrasonic beam. The light diffraction measurements are based on the Raman-Nath model of ultrasonic continuous-wave light diffraction. The diffracted light intensity can be expressed as an integration of sound pressure(More)
In the present study we have, by theoretical and experimental investigations, especially concentrated on the importance of acoustic streaming, transient cavitation and microstreaming in the fluid close to the stone. Artificial stones, round stones 20 mm in diameter made of Plaster of Paris or rectangular flat stones, 25 x 25 x 15 mm, were suspended in a(More)
In its Fourth Synthesis Report published in 2007, the Intergovernmental Panel on Climate Change (IPCC) demonstrated that in spite of efforts to reduce greenhouse gas emissions, certain impacts of climate change will be inevitable. Two types of measures are necessary to confront climate change: mitigation measures and adaptation measures. Mitigation measures(More)
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