125,294 research outputs found
Heart Rate Patterns Observed in Medical Monitoring
Medical monitoring of heart rate patterns during conditions of sleep, quiet rest, breath-holding, hypoxia, and increased g forces of aircraft fligh
Haldane fractional statistics in the fractional quantum Hall effect
We have tested Haldane's ``fractional-Pauli-principle'' description of
excitations around the state in the FQHE, using exact results for
small systems of electrons. We find that Haldane's prediction
for quasiholes and quasiparticles, respectively, describes our results well
with the modification rather than . We also find
that this approach enables us to better understand the {\it energetics\/} of
the ``daughter'' states; in particular, we find good evidence, in terms of the
effective interaction between quasiparticles, that the states and
4/13 should not be stable.Comment: 9 pages, 3 Postscript figures, RevTex 3.0. (UCF-CM-93-005
Composition of the hot plasma near geosynchronous altitude
Although there were no direct measurements of the composition of the hot (keV) plasma at geosynchronous altitudes, the combination of other observations leads to the conclusion that, at least during geomagnetically disturbed periods, there are significant fluxes of ions heavier than protons in this region. Ion composition measurements below 8000 km altitude show upward streaming fluxes of both O(+) and H(+) ions in the L-region of the geosynchronous orbit. These observations are consistent with the conclusion that at least a portion of the total ion fluxes observed at geosynchronous altitude to be highly peaked near the magnetic field lines are heavier than protons and originate in the ionosphere
Testing equality of variances in the analysis of repeated measurements
The problem of comparing the precisions of two instruments using repeated measurements can be cast as an extension of the Pitman-Morgan problem of testing equality of variances of a bivariate normal distribution. Hawkins (1981) decomposes the hypothesis of equal variances in this model into two subhypotheses for which simple tests exist. For the overall hypothesis he proposes to combine the tests of the subhypotheses using Fisher's method and empirically compares the component tests and their combination with the likelihood ratio test. In this paper an attempt is made to resolve some discrepancies and puzzling conclusions in Hawkins's study and to propose simple modifications.\ud
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The new tests are compared to the tests discussed by Hawkins and to each other both in terms of the finite sample power (estimated by Monte Carlo simulation) and theoretically in terms of asymptotic relative efficiencies
Degenerate principal series of quantum Harish-Chandra modules
In this paper we study a quantum analogue of a degenerate principal series of
-modules () related to the Shilov boundary of
the quantum -matrix unit ball. We give necessary and sufficient
conditions for the modules to be simple and unitarizable and investigate their
equivalence.
These results are q-analogues of known classical results on reducibility and
unitarizability of SU(n,n)-modules obtained by Johnson, Sahi, Zhang, Howe and
Tan.Comment: 33 pages, 4 figure
Research and study in system optimization techniques Second quarterly progress report, Feb. 14 - May 14, 1965
Systems optimization for motion stability matrix problem - predictive guidance for Thor vehicle trajector
Expectation values of single-particle operators in the random phase approximation ground state
We developed a method for computing matrix elements of single-particle
operators in the correlated random phase approximation ground state. Working
with the explicit random phase approximation ground state wavefunction, we
derived practically useful and simple expression for a molecular property in
terms of random phase approximation amplitudes. The theory is illustrated by
the calculation of molecular dipole moments for a set of representative
molecules.Comment: Accepted to J.Chem.Phy
Automatic photointerpretation for plant species and stress identification (ERTS-A1)
The author has identified the following significant results. Automatic stratification of forested land from ERTS-1 data provides a valuable tool for resource management. The results are useful for wood product yield estimates, recreation and wildlife management, forest inventory, and forest condition monitoring. Automatic procedures based on both multispectral and spatial features are evaluated. With five classes, training and testing on the same samples, classification accuracy of 74 percent was achieved using the MSS multispectral features. When adding texture computed from 8 x 8 arrays, classification accuracy of 90 percent was obtained
Reliable First-Principles Alloy Thermodynamics via Truncated Cluster Expansions
In alloys cluster expansions (CE) are increasingly used to combine
first-principles electronic-structure and Monte Carlo methods to predict
thermodynamic properties. As a basis-set expansion in terms of lattice
geometrical clusters and effective cluster interactions, the CE is exact if
infinite, but is tractable only if truncated. Yet until now a truncation
procedure was not well-defined and did not guarantee a reliable truncated CE.
We present an optimal truncation procedure for CE basis sets that provides
reliable thermodynamics. We then exemplify its importance in NiV, where the
CE has failed unpredictably, and now show agreement to a range of measured
values, predict new low-energy structures, and explain the cause of previous
failures.Comment: 4 pages, 2 figure
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