8,621 research outputs found
CANOZE measurements of the Arctic ozone hole
In CANOZE 1 (Canadian Ozone Experiment), a series of 20 ozone profile measurements were made in April, 1986 from Alert at 82.5 N. CANOZE is the Canadian program for study of the Arctic winter ozone layer. In CANOZE 2, ozone profile measurements were made at Saskatoon, Edmonton, Churchill and Resolute during February and March, 1987 with ECC ozonesondes. Ground based measurements of column ozone, nitrogen dioxide and hydrochloric acid were conducted at Saskatoon. Two STRATOPROBE balloon flights were conducted on February 26 and March 19, 1987. Two aerosol flights were conducted by the University of Wyoming. The overall results of this study will be reported and compared with the NOZE findings. The results from CANOZE 3 in 1988, are also discussed. In 1988, as part of CANOZE 3, STRATOPROBE balloon flights were conducted from Saskatchewan on January 27 and February 13. A new lightweight infrared instrument was developed and test flown. A science flight was successfully conducted from Alert (82.5 N) on March 9, 1988 when the vortex was close to Alert; a good measurement of the profile of nitric acid was obtained. Overall, the Arctic spring ozone layer exhibits many of the features of the Antarctic ozone phenomenon, although there is obviously not a hole present every year. The Arctic ozone field in March, 1986 demonstrated many similarities to the Antarctic ozone hole. The TOMS imagery showed a crater structure in the ozone field similar to the Antarctic crater in October. Depleted layers of ozone were found in the profiles around 15 km, very similar to those reported from McMurdo. Enhanced levels of nitric acid were measured in air which had earlier been in the vortex. The TOMS imagery for March 1987 did not show an ozone crater, but will be examined for an ozone crater in February and March, 1988, the target date for the CANOZE 3 project
Steady internal flow and aerodynamic loads analysis of shuttle thermal protection system
An analytical model for calculation of ascent steady state tile loading was developed and validated with wind tunnel data. The analytical model is described and results are given. Results are given for loading due to shocks and skin friction. The analysis included calculation of internal flow (porous media flow and channel flow) to obtain pressures and integration of the pressures to obtain forces and moments on an insulation tile. A heat transfer program was modified by using analogies between heat transfer and fluid flow so that it could be used for internal flow calculation. The type of insulation tile considered was undensified reusable surface insulation (RSI) without gap fillers, and the location studied was the lower surface of the orbiter. Force and moment results are reported for parameter variations on surface pressure distribution, gap sizes, insulation permeability, and tile thickness
Letters between B. H. Rawl and W. J. Kerr
Letters concerning a position in animal husbandry at Utah Agricultural College
Letters between W. H. Philbrick and W. J. Kerr
Letters concerning recommendation for position in music department at Utah Agricultural College
While The Stars In The Heavens Shine On
https://digitalcommons.library.umaine.edu/mmb-vp/4404/thumbnail.jp
The energy budget in Rayleigh-Benard convection
It is shown using three series of Rayleigh number simulations of varying
aspect ratio AR and Prandtl number Pr that the normalized dissipation at the
wall, while significantly greater than 1, approaches a constant dependent upon
AR and Pr. It is also found that the peak velocity, not the mean square
velocity, obeys the experimental scaling of Ra^{0.5}. The scaling of the mean
square velocity is closer to Ra^{0.46}, which is shown to be consistent with
experimental measurements and the numerical results for the scaling of Nu and
the temperature if there are strong correlations between the velocity and
temperature.Comment: 5 pages, 3 figures, new version 13 Mar, 200
Altitude Limits for Rotating Vector Model Fitting of Pulsar Polarization
Traditional pulsar polarization sweep analysis starts from the point dipole
rotating vector model (RVM) approximation. If augmented by a measurement of the
sweep phase shift, one obtains an estimate of the emission altitude
(Blaskiewicz, Cordes, & Wasserman). However, a more realistic treatment of
field line sweepback and finite altitude effects shows that this estimate
breaks down at modest altitude ~ 0.1R_{LC}. Such radio emission altitudes turn
out to be relevant to the young energetic and millisecond pulsars that dominate
the \gamma-ray population. We quantify the breakdown height as a function of
viewing geometry and provide simple fitting formulae that allow observers to
correct RVM-based height estimates, preserving reasonable accuracy to R ~
0.3R_{LC}. We discuss briefly other observables that can check and improve
height estimates
Particle detection experiment for Applications Technology Satellite 1 /ATS-1/ Final report
Applications technology satellite particle detection experiment for measuring energy spectra of earth magnetic fiel
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