36,907 research outputs found
The Nonprofit Hospital Exemption of the National Labor Relations Act: Application to the University-Operated Hospital in Duke University
This work extends our recent work on proving that the particle filter converge for unbounded function to a more general case. More specifically, we prove that the particle filter converge for unbounded functions in the sense of L p-convergence, for an arbitrary p greater than 1. Related to this, we also provide proofs for the case when the function we are estimating is bounded. In the process of deriving the main result we also established a new Rosenthal type inequality
Collective modes of a harmonically trapped one-dimensional Bose gas: the effects of finite particle number and nonzero temperature
Following the idea of the density functional approach, we develop a
generalized Bogoliubov theory of an interacting Bose gas confined in a
one-dimensional harmonic trap, by using a local chemical potential - calculated
with the Lieb-Liniger exact solution - as the exchange energy. At zero
temperature, we use the theory to describe collective modes of a
finite-particle system in all interaction regimes from the ideal gas limit, to
the mean-field Thomas-Fermi regime, and to the strongly interacting
Tonks-Girardeau regime. At finite temperature, we investigate the temperature
dependence of collective modes in the weak-coupling regime by means of a
Hartree-Fock-Bogoliubov theory with Popov approximation. By emphasizing the
effects of finite particle number and nonzero temperature on collective mode
frequencies, we make comparisons of our results with the recent experimental
measurement [E. Haller et al., Science 325, 1224 (2009)] and some previous
theoretical predictions. We show that the experimental data are still not fully
explained within current theoretical framework.Comment: 10 pages, 8 figure
Coherent transport of armchair graphene constrictions
The coherent transport properties of armchair graphene nanoconstrictions(GNC)
are studied using tight-binding approach and Green's function method. We find a
non-bonding state at zero Fermi energy which results in a zero conductance
valley, when a single vacancy locates at of a perfect metallic
armchair graphene nanoribbon(aGNR). However, the non-bonding state doesn't
exist when a vacancy locates at y=3n, and the conductance behavior of lowest
conducting channel will not be affected by the vacancy. For the square-shaped
armchair GNC consisting of three metallic aGNR segments, resonant tunneling
behavior is observed in the single channel energy region. We find that the
presence of localized edge state locating at the zigzag boundary can affect the
resonant tunneling severely. A simplified one dimensional model is put forward
at last, which explains the resonant tunneling behavior of armchair GNC very
well.Comment: 6 pages, 11 figure
Protein folding in hydrophobic-polar lattice model: a flexible ant colony optimization approach
This paper proposes a flexible ant colony (FAC) algorithm for solving protein folding problems based on the hydrophobic-polar square lattice model. Collaborations of novel pheromone and heuristic strategies in the proposed algorithm make it more effective in predicting structures of proteins compared with other state-of-the-art algorithms
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