Publications by authors named "Joshua Carmichael"

The geometry of the Mach cone produced by a supersonic source is analyzed and mapped into initial conditions used in acoustic ray tracing. The resulting source model is combined with spherical geometry ray tracing methods to enable propagation simulations for infrasonic signals produced by bolides, space debris, rockets, aircraft, and other fast-than-sound sources out to typical infrasonic observation distances of hundreds or thousands of kilometers. Idealized linear and parabolic trajectories typical of bolides and rockets, respectively, are used to demonstrate the calculation of regional infrasonic signals produced by such sources and characteristics of the radiated infrasonic waves are found to vary strongly with the geometry of the trajectory and atmospheric structure.

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While there have been great strides in endoscopic and endoscope-assisted neurosurgical approaches, particularly in the treatment of deep-sited brain and skull base tumours, the greatest technical barrier to their adoption has been the availability of suitable surgical instruments. This systematic review seeks to identify specialised instruments for these approaches and evaluate their safety, efficacy and usability. Conducted in accordance with the PRISMA guidelines, Medline, Embase, CENTRAL, SCOPUS and Web of Science were searched.

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Endoscopic endonasal skull base surgery is a promising alternative to transcranial approaches. However, standard instruments lack articulation, and thus, could benefit from robotic technologies. The aim of this study was to develop an ergonomic handle for a handheld robotic instrument intended to enhance this procedure.

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Physical and deployment factors that influence infrasound signal detection and assess automatic detection performance for a regional infrasound network of arrays in the Western U.S. are explored using signatures of ground truth (GT) explosions (yields).

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