36,932 research outputs found
Standard arc welders provide high amperage direct current source
Standard arc welders or power supplies are hooked up in parallel or series connections to obtain an adequate supply of current or voltage for various purposes. This method provides maximum flexibility in a wide range of voltages and currents
Measurement of model aeroelastic deformations in the wind tunnel at transonic speeds using stereophotogrammetry
A stereophotographic method of determining the aeroelastic deformations of an airplane model under aerodynamic load in the wind tunnel was evaluated. Wind tunnel tests were conducted in the Langley 8 foot transonic pressure tunnel on the wing of a 0.0625 scale model of the TF-8A supercritical wing research airplane to obtain simultaneously the aerodynamic forces and moments, pressure distributions, and stereophotographs. Tests were conducted at Mach numbers of 0.80, 0.95, and 1.20, and at free stream dynamic pressures of 20,349 Pa and 40,698 Pa. Accuracy of the stereophotographic technique in determining wing deflections was within 0.013 cm under static conditions. This value translates to an error in wing twist of 0.10 deg inboard and increases to 0.20 deg outboard. When the model was under aerodynamic load in the wind tunnel, the accuracy of the stereophotographic technique of determining wind deflections increased to 0.052 cm when compared with static wing loadings because of the dynamic motion of the model in the tunnel
The Future of Particle Physics
After a very brief review of twentieth century elementary particle physics,
prospects for the next century are discussed. First and most important are
technological limits of opportunities; next, the future experimental program,
and finally the status of the theory, in particular its limitations as well as
its opportunities.Comment: Invited talk given at the International Conference on Fundamental
Sciences: Mathematics and Theoretical Physics, Singapore, 13-17 March 200
Continuously operating induction plasma accelerator Patent
Continuous operation, single phased, induction plasma accelerator producing supersonic speed
Directly comparing coronal and solar wind elemental fractionation
As the solar wind propagates through the heliosphere, dynamical processes
irreversibly erase the signatures of the near-Sun heating and acceleration
processes. The elemental fractionation of the solar wind should not change
during transit however, making it an ideal tracer of these processes. We aimed
to verify directly if the solar wind elemental fractionation is reflective of
the coronal source region fractionation, both within and across different solar
wind source regions. A backmapping scheme was used to predict where solar wind
measured by the Advanced Composition Explorer (ACE) originated in the corona.
The coronal composition measured by the Hinode Extreme ultraviolet Imaging
Spectrometer (EIS) at the source regions was then compared with the in-situ
solar wind composition. On hourly timescales there was no apparent correlation
between coronal and solar wind composition. In contrast, the distribution of
fractionation values within individual source regions was similar in both the
corona and solar wind, but distributions between different sources have
significant overlap. The matching distributions directly verifies that
elemental composition is conserved as the plasma travels from the corona to the
solar wind, further validating it as a tracer of heating and acceleration
processes. The overlap of fractionation values between sources means it is not
possible to identify solar wind source regions solely by comparing solar wind
and coronal composition measurements, but a comparison can be used to verify
consistency with predicted spacecraft-corona connections.Comment: Accepted version; 8 pages, 7 figure
Applicability of Skylab remote sensing for detection and monitoring of surface mining activities
There are no author-identified significant results in this report
Applicability of satellite remote sensing for monitoring surface mining activities
There are no author-identified significant results in this report
Model-Independent Description and Large Hadron Collider Implications of Suppressed Two-Photon Decay of a Light Higgs Boson
For a Standard Model Higgs boson with mass between 115 GeV and 150 GeV, the
two-photon decay mode is important for discovery at the Large Hadron Collider
(LHC). We describe the interactions of a light Higgs boson in a more
model-independent fashion, and consider the parameter space where there is no
two-photon decay mode. We argue from generalities that analysis of the discovery mode outside its normally thought of range of applicability is
especially needed under these circumstances. We demonstrate the general
conclusion with a specific example of parameters of a type I two-Higgs doublet
theory, motivated by ideas in strongly coupled model building. We then specify
a complete set of branching fractions and discuss the implications for the LHC.Comment: 4 pages, 4 figure
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