Abstract Neural networks (NN) are taking over ever more decisions thus far taken by humans, even though verifiable system-level guarantees out of reach. Neither is the verification technology available, nor it understood what a formal, meaningful, extensible, and scalable testbed might look like for such technology. The present paper an attempt to improve on both above aspects. We family formal...

A MODULAR PARTICLE-CONTINUUM NUMERICAL ALGORITHM FORHYPERSONIC NON-EQUILIBRIUM FLOWS byThomas Edward Schwartzentruber Chairperson: Iain D. Boyd Hypersonic vehicles traveling at high altitudes experience conditions ranging fromrarefied to continuum flow. Even within a mostly continuum flow, there may belocal regions of rarefied (or non-equilibrium) flow generated by sharp leading...

In [16] a visco-elastic relaxation system, called the relaxed Burnett system, was proposed by Jin and Slemrod as a moment approximation to the Boltzmann equation. The relaxed Burnett system is weakly parabolic, has a linearly hyperbolic convection part, and is endowed with a generalized entropy inequality. It agrees with the solution of the Boltzmann equation up to the Burnett order via the Cha...

This article describes the development of an integrated physical model for the rf diode sputtering of metal thin films. The model consists of: ~1! a computational fluid dynamic finite element model for the velocity and pressure distribution of the working gas Ar flow in the chamber, ~2! a steady-state plasma model for the flux and energy of Ar ions striking the target and the substrate, ~3! a m...

It is well known that for increasingly rarefied flowfields, the predictions from continuum formulation, such as the Navier–Stokes equations lose accuracy. For the high speed diatomic molecular flow in the transitional regime, the inaccuracies are partially attributed to the single temperature approximations in the Navier–Stokes equations. Here, we propose a continuum multiple temperature model ...

Linear instability of high-speed boundary layers is routinely examined assuming quiescent edge conditions, without reference to the internal structure shocks or instabilities potentially generated in them. Our recent work has shown that kinetically modeled nonequilibrium zone straight away from solid boundaries exhibits low-frequency molecular fluctuations. The presence dominant low frequencies...