995 research outputs found
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Recordings of Ple-Temiar Dream Music
A piece written about the events of the night of recording the Dream Music as well as some background information about how the whole night came together. It goes on to explain the importance of the recordings and the impact of war and H.D. Noone going missing, and the ability to record the Temiar again
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A Letter from Eric Robertson to John Wren-Lewis
This letter refers to questions John Wren-Lewis
had asked Eric Robertson
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Draft Notes and Responses
These are the draft notes and final responses
written by Eric Robertson in answer to the
queries and statements posed by John Wren-
Lewis to Tony Beamish, Eric Robertson and
Peggy Robertson
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Instructions for Processing Recordings of Temiar Dream Music
A short note on how the Temiar Dream Music
should be re-recorded onto a more sturdier form
of disc
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Instruction to Copy Discs
This letter to a Mr Glover at the British Ministry of Information contains information as to what should be done to the recordings made in the December of 1941 of the Ple-Temiar community
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Eric Robertson’s CV
The CV of Eric Robertson from the beginning of his education in 1921 to the appointment of his most current position for the BBC, at the time of writing his CV, on April 15th 1945
ON THE VORTEX BREAKDOWN PHENOMENON IN HIGH ANGLE OF ATTACK FLOWS OVER DELTA WING GEOMETRIES
ABSTRACT Using computational methods, an investigation was performed on the physical mechanisms leading to vortex breakdown in high angle of attack flows over delta wing geometries. For this purpose, the Second International Vortex Flow Experiment (VFE-2) 65° sweep delta wing model was studied at a root chord Reynolds number (Re cr ) of 6 × 10 6 at various angles of attack. The open-source computational fluid dynamics (CFD) solver OpenFOAM was used in parallel with the commercial CFD solver ANSYS® FLUENT. For breadth, a variety of classic closure models were applied, including unsteady Reynolds-averaged Navier-Stokes (URANS) and detached eddy simulation (DES). Results for all cases are analyzed and flow features are identified and discussed. The results show the inception of a pair of leading edge vortices originating at the apex for all models used, and a region of steady vortical structures downstream in the URANS results. However, DES results show regions of massively separated helical flow which manifests after vortex breakdown. Analysis of turbulence quantities in the breakdown region gives further insight into the mechanisms leading to such phenomena
Two-Dimensional Hydrodynamic Simulations of Convection in Radiation-Dominated Accretion Disks
The standard equilibrium for radiation-dominated accretion disks has long
been known to be viscously, thermally, and convectively unstable, but the
nonlinear development of these instabilities---hence the actual state of such
disks---has not yet been identified. By performing local two-dimensional
hydrodynamic simulations of disks, we demonstrate that convective motions can
release heat sufficiently rapidly as to substantially alter the vertical
structure of the disk. If the dissipation rate within a vertical column is
proportional to its mass, the disk settles into a new configuration thinner by
a factor of two than the standard radiation-supported equilibrium. If, on the
other hand, the vertically-integrated dissipation rate is proportional to the
vertically-integrated total pressure, the disk is subject to the well-known
thermal instability. Convection, however, biases the development of this
instability toward collapse. The end result of such a collapse is a gas
pressure-dominated equilibrium at the original column density.Comment: 10 pages, 7 figures, accepted for publication in ApJ. Please send
comments to [email protected]
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Spin-density-wave antiferromagnetism of Cr in Fe/Cr(001) superlattices
The antiferromagnetic spin-density-wave (SDW) order of Cr layers in Fe/Cr(001) superlattices was investigated by neutron scattering. For Cr thickness 51-190 {Angstrom}, a transverse SDW is formed for all temperatures below Neel temperature with a single wavevector Q normal to the layers. A coherent magnetic structure forms with the nodes of the SDW near the Fe-Cr interfaces. For thinner Cr layers, the magnetic scattering can be described by commensurate antiferromagnetic order
Transit Timing Observations from Kepler: VII. Confirmation of 27 planets in 13 multiplanet systems via Transit Timing Variations and orbital stability
We confirm 27 planets in 13 planetary systems by showing the existence of
statistically significant anti-correlated transit timing variations (TTVs),
which demonstrates that the planet candidates are in the same system, and
long-term dynamical stability, which places limits on the masses of the
candidates---showing that they are planetary. %This overall method of planet
confirmation was first applied to \kepler systems 23 through 32. All of these
newly confirmed planetary systems have orbital periods that place them near
first-order mean motion resonances (MMRs), including 6 systems near the 2:1
MMR, 5 near 3:2, and one each near 4:3, 5:4, and 6:5. In addition, several
unconfirmed planet candidates exist in some systems (that cannot be confirmed
with this method at this time). A few of these candidates would also be near
first order MMRs with either the confirmed planets or with other candidates.
One system of particular interest, Kepler-56 (KOI-1241), is a pair of planets
orbiting a 12th magnitude, giant star with radius over three times that of the
Sun and effective temperature of 4900 K---among the largest stars known to host
a transiting exoplanetary system.Comment: 12 pages, 13 figures, 5 tables. Submitted to MNRA
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