According to the kinematic theory of nonhelical dynamo action, the magnetic energy spectrum increases with wavenumber and peaks at the resistive cutoff wavenumber. It has previously been argued that even in the dynamical case, the magnetic energy peaks at the resistive scale. Using high resolution simulations (up to 10243 meshpoints) with no large-scale imposed field, we show that the magnetic ...

We consider the development of nonlinear three-dimensional vortex–wave interaction equilibria of laminar plane Couette flow for a range of spanwise wavenumbers. The results are computed using a hybrid approach that captures the required asymptotic structure while at the same time providing a direct link with full numerical calculations of equilibrium states. Each equilibrium state consists of a...

Space and astrophysical plasmas often develop into a turbulent state and exhibit nearly random and stochastic motions. While earlier studies emphasize more on understanding the energy spectrum of turbulence in the one-dimensional context (either in the frequency or the wavenumber domain), recent achievements in plasma turbulence studies provide an increasing amount of evidence that plasma turbu...

Linear forcing has been proposed as a useful method for forced isotropic turbulence simulations because it is a physically realistic forcing method with a straightforward implementation in physical-space numerical codes T. S. Lundgren, “Linearly forced isotropic turbulence,” Annual Research Briefs Center for Turbulence Research, Stanford, CA, 2003 , p. 461; C. Rosales and C. Meneveau, “Linear f...

The equatorial atmospheric variability shows a spectrum of significant peaks in the wavenumber– frequency domain. These peaks have been identified with the equatorially trapped wave modes of rotating shallow water wave theory. This paper addresses the observation that the various wave types (e.g., Kelvin, Rossby, etc.) and wavenumbers show differing signal strength relative to a red background....

Precise azimuth-variant motion compensation (MOCO) is an essential and difficult task for high-resolution synthetic aperture radar (SAR) imagery. In conventional post-filtering approaches, residual azimuth-variant motion errors are generally compensated through a set of spatial post-filters, where the coarse-focused image is segmented into overlapped blocks concerning the azimuth-dependent resi...

Periodic traveling waves (wavetrains) have been extensively studied for reaction-diffusion equations. One important motivation for this work has been the identification of periodic traveling wave patterns in spatiotemporal data sets in ecology. However, for many ecological populations, diffusion is no more than a rough phenomenological representation of dispersal, and spatial convolution with a...

The existing evidence for the nature of the phase diagram for the binary system sodium nitrate-potassium nitrate is reviewed and in particular whether the system is of the continuous solid solution type, as has often been stated in the last 80 years, or whether this system is of the eutectic type as was earlier believed and has again been asserted recently. Additional evidence from Raman spectr...

This study carries out the edge-reflection analysis of guided waves in a 3-D plate. First, we excite an incident guided wave by applying a normal traction on the surface of a 3-D plate. The excited wave field is obtained in the frequency and wavenumber domains. Secondly, we perform the edge-reflection analysis in the frequency and wavenumber domains by applying the mode-decomposition method to ...