Temporal decorrelations in compressible isotropic turbulence are studied using the space-time correlation theory and direct numerical simulation. A swept-wave model is developed for dilatational components, while the classic random sweeping model is proposed for solenoidal components. The swept-wave model shows that the temporal decorrelations in dilatational fluctuations are dominated by two p...

Swept-source optical coherence tomography (OCT) is the latest advancement in anterior segment imaging. There are limited data regarding its performance after laser in situ keratomileusis (LASIK). We compared the reliability of swept-source OCT and Scheimpflug imaging for evaluation of corneal parameters in refractive surgery candidates with myopia or myopic astigmatism. Three consecutive measur...

This paper compares 2 approaches to 3-D ultrasonic axial strain imaging: a tracked ultrasound probe swept manually over a volume, and a mechanically-swept 3-D probe. We find that high-quality data are more easily obtained using the 3-D probe, but the freehand approach may be more practical in certain scanning situations.

We present characteristics of a wavelength swept laser with a scanning fiber Fabry-Perot filter at 1300 nm. We investigate the dependence of the scanning frequencies in the swept laser. In conventional wavelength swept lasers, the relative intensity of the laser output decreases significantly as the scanning frequency increases. The peak wavelength of the output spectrum is red-shifted due to t...

We demonstrate a frequency comb (FC) swept laser and a frequency comb Fourier domain mode locked (FCFDML) laser for applications in optical coherence tomography (OCT). The fiber-based FC swept lasers operate at a sweep rate of 1kHz and 120kHz, respectively, over a 135nm tuning range centered at 1310nm with average output powers of 50mW. A 25GHz free spectral range frequency comb filter in the c...

A severe dust storm blanketing Central Asia on 3–4 November 2021 was investigated employing satellite remote-sensing, synoptic meteorological observations, reanalysis and HYSPLIT back-trajectories. The prevailing conditions showed an intensification of air subsidence over eastern Kazakhstan, featured in a typical omega-blocking system the region two troughs to its west east axis, one day before...

The Breguet range equation indicates that to the first order of approximation range will be maximized by maximizing ML/D, where M is the Mach number and L/D is the lift/drag ratio. Since the drag coefficient increases very rapidly as the Mach number approaches one, this leads to the design of a long range aircraft which fly at high subsonic speeds, typically in the range Mach 0.8 to 0.85, just ...