It is shown that a slender elastic fiber moving in a Stokesian fluid can be susceptible to a buckling instability--termed the "stretch-coil" instability--when moving in the neighborhood of a hyperbolic stagnation point of the flow. When the stagnation point is part of an extended cellular flow, it is found that immersed fibers can move as random walkers across time-independent closed-streamline...

Temperature is an important parameter in most high speed flow experiments, but it is sometimes a difficult parameter to measure, particularly in short-duration facilities. Stagnation temperature measurements have been obtained using transient thin film heat flux probes in a Mach 6 carbon dioxide flow produced by the Oxford University Gun Tunnel. The probes were operated over a range of surface ...

We examine how aggregate output and income distribution interact with accumulation of intangible capital over time and across individuals. We consider an overlapping generations economy in which managerial skill (intangible capital) is essential for production, and it is acquired by young workers through on-the-job training by old managers. We show that, when young trainees are not committed to...

In a world where poor countries provide weak protection for intellectual property rights, market integration will systematically shift technical change in favor of rich nations. For this reason, free trade can increase international income differences. At the same time, integration with countries where intellectual property rights are weakly protected can have a large adverse effect on the worl...

Cf = skin friction coefficient CD = drag coefficient CDf = friction drag coefficient CDp = pressure drag coefficient h = step height M0 = freestream Mach number Patm = atmospheric pressure Pi = stagnation pressure Re = freestream Reynolds number Ti = stagnation temperature U = velocity U = normalized velocity Uτ = friction velocity X = longitudinal coordinate Z = vertical coordinate Z = normali...

Steady two dimensional MHD stagnation point flow of a power law fluid over a stretching surface is investigated when the surface is stretched in its own plane with a velocity proportional to the distance from the stagnation point. The fluid impinges on the surface is considered orthogonally. Numerical and analytical solutions are obtained for different cases.

Growth of human population shows no signs of stagnation. The only small disturbance is identified as being probably associated with the coinciding impacts of five demographic catastrophes. The concept of the Epoch of Malthusian Stagnation is convincingly contradicted by empirical evidence.

Introduction. This announcement deals with the subject of continuous flows in the Euclidean plane. I t has long been known (cf. [ l]) tha t every closed set in the plane is the invariant set of some continuous flow. In a recent paper [2], this author has shown that the same statement is not true for flows all of whose orbits are closed in the plane. In fact a necessary and sufficient condition ...

We present an alternative model for the formation of fast low-ionization emission regions (FLIERs) in planetary nebulae that is able to account for many of their attendant characteristics and circumvent the problems on the collimation/formation mechanisms found in previous studies. In this model, the section of the stellar wind flowing along the symmetry axis carries less mechanical momentum th...

The drinking water quality changes during the transport through distribution systems. Domestic drinking water systems (DDWSs), which include the plumbing between the water meter and consumer's taps, are the most critical points in which water quality may be affected. In distribution networks, the drinking water temperature and water residence time are regarded as indicators of the drinking wate...