We investigate the growth of self-organized tubes formed by injection of metal salt solutions into silicate solution. The wall thickness increases strictly in an inward direction and obeys square root functions suggesting the presence of a traveling reaction-diffusion front in the radial direction. We also demonstrate the construction of multi-layered tubes.

Flux-limited Keller-Segel (FLKS) model has been recently derived from kinetic transport models for bacterial chemotaxis and shown to represent better the collective movement observed experimentally. Recently, associated to the kinetic model, a new instability formalism has been discovered related to stiff chemotactic response. This motivates our study of traveling wave and aggregation in popula...

Studies reported in the last Quarterly Progress Report (1) have been modified and extended. The purpose of these studies is to find a formal basis and justification for Pierce's coupling-of-modes formalism (2) as it applies to uniform slowwave structures containing two or more subsystems that individually propagate slow waves (e.g., traveling-wave tubes). If it can be assumed that the coupling ...

This paper describes the design, fabrication, and measurement of backward-wave-cancelled distributed traveling-wave photodetectors. One of the fundamental issues in traveling-wave photodetectors is the generation of backward-waves, which reduces bandwidth or, in the case of matched input termination, reduces their radio-frequency (RF) efficiencies by up to 6 dB. We report a traveling-wave photo...

In this paper, we employ the modified simple equation method to find the exact traveling wave solutions involving parameters of nonlinear evolution equations via the (1+1)dimensional generalized shallow water-wave equation and the(2+1)-dimensional KdV-Burgers equation. When these parameters are taken to be special values, the solitary wave solutions are derived from the exact traveling wave sol...

This article concerns the traveling wave solutions of nonlocal delay reaction-diffusion equations without local quasimonotonicity. The existence of traveling wave solutions is obtained by constructing upper-lower solutions and passing to a limit function. The nonexistence of traveling wave solutions is also established by the theory of asymptotic spreading. The results are applied to a food lim...