Dynamical Alignment in Three Species Tokamak Edge Turbulence

Three dimensional computations of self consistent three species gyrofluid turbulence are carried out for tokamak edge conditions. Profiles as well as disturbances in dependent variables are followed, running the dynamical system to transport equilibrium. The third species density shows a significant correlation with that of the electrons, regardless of initial conditions and drive mechanisms. For decaying systems the densities evolve toward each other. Companion tests with a simple two dimensional drift wave model show this persists even if the third species is a passively advected test field. Similarity in the transport character of electrons and the trace species does not imply that the electrons themselves have a test particle transport character.Comment: RevTeX 4, 21 pages, 15 figures, submitted to Physics of Plasma

Private Schooling in the U.S.: Expenditures, Supply, and Policy Implications

This report provides a first-of-its-kind descriptive summary of private school expenditures. It includes comparisons of expenditures among different types and affiliations of private schools, and it also compares those expenditures with public school expenditures for districts in the same state and labor market. Results indicate that (1) the less-regulated private school sector is more varied in many key features (teacher attributes, pay and school expenditures) than the more highly regulated public schooling sector; (2) these private school variations align and are largely explained by affiliation -- primarily religious affiliation -- alone; and (3) a ranking of school sectors by average spending correlates well with a ranking of those sectors by average standardized test scores

Desmognathus apalachicolae

Number of Pages: 2Integrative BiologyGeological Science

Repair of honeycomb panels with welded breakaway studs

Damaged metallic honeycomb panels can be repaired by drilling holes and welding breakaway studs to both facing sheets. Minimal heat required for welding reduces distortion of highly stressed panels. Repairs can be made without the use of doublers and with greater strength when doublers are used

Zonal Flows and Electromagnetic Drift Wave Turbulence

Detailed computations of tokamak edge turbulence in three dimensional, globally consistent flux tube geometry show an inhibition of the standard scenario in which zonal ExB flows generated by the turbulence should lead to transport barrier formation. It is found by comparison to slab geometry and by analysis of the energetics that the zonal flow energy is depleted by toroidal coupling to the pressure through the geodesic curvature. Edge transport barriers would then depend on the physics of the neoclassical equilibrium.Comment: 14 pages including 5 figures, submitted to Physics Letters

Derivation via free energy conservation constraints of gyrofluid equations with finite-gyroradius electromagnetic nonlinearities

The derivation of electromagnetic gyrofluid equations is made systematic by using the Hermite polynomial form of the underlying delta-f gyrokinetic distribution function. The gyrokinetic free-energy functional is explicitly used to set up the model. The gyrofluid free energy follows directly. The interaction term in the gyrokinetic Lagrangian is used to obtain the gyrofluid counterpart, from which the polarisation equation follows. One closure rule is decided for taking moments over the kinetic gyroaveraging operator. These steps fix the rest of the derivation of the conservative part of the gyrofluid equations. Dissipation is then added in a form to obtain positive definite dissipation and to obtain the collisional fluid equations in their appropriate limit. Existing results are recovered, with the addition of a completely consistent model for finite gyroradius effects in the nonlinearities responsible for magnetic reconnection.Comment: RevTeX 4, 39 pages, no figures, submitted to Physics of Plasmas. From version 1, corrected minor errors in equations, re-did some explanations, added some references, From version 2, added a section on correspondence to fluid/MHD models as asked by the referee. This version was accepted by Physics of Plasma

CANADIAN BACKGROUND AND DESCRIPTION

Agricultural and Food Policy,

James Madison's monetary economics

An analysis of Madison's essay, "Money," and a presentation of a model giving rise to equilibria that mimic general observations about the consequences of government policies like the one Madison describes for limiting inflation.Money ; Money theory ; Debts, Public