32,996 research outputs found
Latitude variation of recurrent fluxes in the outer solar system
Recurrent low energy (greater than or = to 0.5 MeV) proton flux enhancements, reliable indicators of corotating plasma interaction regions, were observed on the Voyager 1 and 2 and Pioneer 11 spacecraft in the heliographic latitude range 2 deg S to 23 N and the heliocentric radial range 11 to 20 AU. After a period of rather high correlation between fluxes at different latitudes in early 1983, distinct differences developed in the fluxes during an overall flux decrease. The flux intensities returned to higher levels in early 1984 and differences in both the recurrence frequency and flux intensity persisted into 1985, as Voyager 1 traveled to 23 AU and 25 N latitude. Intercomparison of data from the three spacecraft indicates that the flux differences are most likely due to latitudinal rather than radial or temporal variations
B(Ds^+ -> l^+ nu) and the Decay Constant f_(D_s^+)
I report final CLEO-c results on the purely leptonic decays of the D_s^+ ->
l^+ nu, for the cases when l^+ is a mu^+ or tau^+, when it decays into pi^+
anti-nu, using 314/pb of data at 4.170 GeV. I also include preliminary results
from the tau^+ -> e^+ nu anti-nu channel using 195/pb. Combining both we
measure f_{D_s}= 275 +/- 10 +/- 5 MeV, and f_{D_s^+}/{f_{D^+}=1.24 +/- 0.10 =/-
0.03 .Comment: Presented at "The 2007 Europhysics Conference on High Energy
Physics," Manchester, England, 19-25 July 2007, to appear in the proceedings.
Three pages, 1 figur
Energy Anomaly and Polarizability of Carbon Nanotubes
The energy of electron Fermi sea perturbed by external potential, represented
as energy anomaly which accounts for the contribution of the deep-lying states,
is analyzed for massive d = 1+1 Dirac fermions on a circle. The anomaly is a
universal function of the applied field, and is related to known
field-theoretic anomalies. We express transverse polarizability of Carbon
nanotubes via the anomaly, in a way which exhibits the universality and
scale-invariance of the response dominated by pi-electrons and qualitatively
different from that of dielectric and conducting shells. Electron band
transformation in a strong-field effect regime is predicted.Comment: 4 pg
Automated Retrieval of Non-Engineering Domain Solutions to Engineering Problems
Organised by: Cranfield UniversityBiological inspiration for engineering design has occurred through a variety of techniques such as creation
and use of databases, keyword searches of biological information in natural-language format, prior
knowledge of biology, and chance observations of nature. This research focuses on utilizing the reconciled
Functional Basis function and flow terms to identify suitable biological inspiration for function based design.
The organized search provides two levels of results: (1) associated with verb function only and (2) narrowed
results associated with verb-noun (function-flow). A set of heuristics has been complied to promote efficient
searching using this technique. An example for creating smart flooring is also presented and discussed.Mori Seiki – The Machine Tool Compan
Neural networks in geophysical applications
Neural networks are increasingly popular in geophysics.
Because they are universal approximators, these
tools can approximate any continuous function with an
arbitrary precision. Hence, they may yield important
contributions to finding solutions to a variety of geophysical applications.
However, knowledge of many methods and techniques
recently developed to increase the performance
and to facilitate the use of neural networks does not seem
to be widespread in the geophysical community. Therefore,
the power of these tools has not yet been explored to
their full extent. In this paper, techniques are described
for faster training, better overall performance, i.e., generalization,and the automatic estimation of network size
and architecture
Effects of an embedding bulk fluid on phase separation dynamics in a thin liquid film
Using dissipative particle dynamics simulations, we study the effects of an
embedding bulk fluid on the phase separation dynamics in a thin planar liquid
film. The domain growth exponent is altered from 2D to 3D behavior upon the
addition of a bulk fluid, even though the phase separation occurs in 2D
geometry. Correlated diffusion measurements in the film show that the presence
of bulk fluid changes the nature of the longitudinal coupling diffusion
coefficient from logarithmic to algebraic dependence of 1/s, where s is the
distance between the two particles. This result, along with the scaling
exponents, suggests that the phase separation takes place through the Brownian
coagulation process.Comment: 6 pages, 5 figures. Accepted for publication in Europhys. Let
Flight test evaluation of a separate surface attitude command control system on a Beech 99 airplane
A joint NASA/university/industry program was conducted to flight evaluate a potentially low cost separate surface implementation of attitude command in a Beech 99 airplane. Saturation of the separate surfaces was the primary cause of many problems during development. Six experienced professional pilots who made simulated instrument flight evaluations experienced improvements in airplane handling qualities in the presence of turbulence and a reduction in pilot workload. For ride quality, quantitative data show that the attitude command control system results in all cases of airplane motion being removed from the uncomfortable ride region
Fluid sample collection and storage device
Fluid sampling device collects a sample from a low-pressure fluid system and stores it for an indefinite period, with little risk of contamination of either the sample or the surrounding environment. The collector /a plastic bladder/ is separated from the sampler after a sample is collected
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