We present hydrodynamical calculations of radiative shocks with low Mach numbers and find that the well-known global overstability can occur if the temperature exponent (α) of the cooling is sufficiently negative. We find that the stability of radiative shocks increases with decreasing Mach number, with the result that M = 2 shocks require α ∼ < −1.2 in order to be overstable. Such values occur...

A temporally resolved flow visualization system that produces 17 flow images over a time span of 128 microseconds is used to visualize the mixing layers of a Mach 1.28 (M c =0.59) and a Mach 2.06 (M c =0.87) ideally expanded high Reynolds number axisymmetric jets. These image sequences revealed details about the effects of compressibility on the dynamics of turbulence structures. In general, th...

Introduction of a single-point mutation (Asn to Tyr) at position 410 at the junction between transmembrane domain 6 and the third extracellular loop of the human M(2) muscarinic acetylcholine (mACh) receptor generated a mutant receptor (N410Y) that possesses many of the hallmark features of a constitutively active mutant receptor. These included enhanced agonist binding affinity and potency, in...

Direct numerical simulation (DNS) is used to study laminar to turbulent transition induced by a discrete hemispherical roughness element in a high-speed laminar boundary layer. The simulations are performed under conditions matching the experiments of Danehy et al. (AIAA Paper 2009–394, 2009) for free-stream Mach numbers of 3.37, 5.26 and 8.23. It is observed that the Mach 8.23 flow remains lam...

This paper introduces a supersonic Korean morphological analyzer named MACH. It analyzes a 1 GB document within 5 minutes on a typical personal computer with a 1 GHz Pentium III CPU. This means that it analyzes about 500,000 words per second. In fact, the analysis speed of MACH is 12-20 times faster than the most famous Korean morphological analyzers. In spite of its supersonic speed, the analy...

We study a family of two-dimensional Riemann problems for compressible flow modeled by the nonlinear wave system. The initial constant states are separated by two jump discontinuities, x = ±κay, which develop into two interacting shock waves. We consider shock angles in a range where regular reflection is not possible. The solution is symmetric about the y-axis and on each side of the y-axis co...

A constraint exists for intrusive probes in transonic flow which leads to a complete insensitivity to static pressure at Mach number Ma=1. Nearby Mach number unity different types of probes are affected more or less by the reduced sensitivity to static pressure or Mach number. In this paper three types of probes are compared and it is shown that the reduced sensitivity near Ma=1 causes large er...

Mach is a new operating system targeted for distributed and multiprocessor environments. Mach contains 4.3BSD compatibility code that, unlike the Mach kernel proper, runs only on a single processor, thus presenting a performance bottleneck to a multiprocessor system. Pieces of the 4.3BSD compatibility code were selectively parallelized to reduce this bottleneck. Signifrcantly improved multiproc...