18,321 research outputs found
Propagation of and Maxwellian weighted bounds for derivatives of solutions to the homogeneous elastic Boltzmann Equation
We consider the -dimensional space homogeneous Boltzmann equation for
elastic collisions for variable hard potentials with Grad (angular) cutoff. We
prove sharp moment inequalities, the propagation of -Maxwellian weighted
estimates, and consequently, the propagation -Maxwellian weighted
estimates to all derivatives of the initial value problem associated to the
afore mentioned problem.
More specifically, we extend to all derivatives of the initial value problem
associated to this class of Boltzmann equations corresponding sharp moment
(Povzner) inequalities and time propagation of -Maxwellian weighted
estimates as originally developed A.V. Bobylev in the case of hard spheres in 3
dimensions; an improved sharp moments inequalities to a larger class of angular
cross sections and -exponential bounds in the case of stationary states to
Boltzmann equations for inelastic interaction problems with `heating' sources,
by A.V. Bobylev, I.M. Gamba and V.Panferov, where high energy tail decay rates
depend on the inelasticity coefficient and the the type of `heating' source;
and more recently, extended to variable hard potentials with angular cutoff by
I.M. Gamba, V. Panferov and C. Villani in the elastic case collision case and
so -Maxwellian weighted estimated were shown to propagate if initial
states have such property. In addition, we also extend to all derivatives the
propagation of -Maxwellian weighted estimates to solutions of the
initial value problem to the Boltzmann equations for elastic collisions for
variable hard potentials with Grad (angular) cutoff.Comment: 24 page
A follow-up study of the 1949 and 1950 graduates of Chandler School for Women, Boston, Massachusetts, and a survey of the employers of the Chandler graduates, with implications for curriculum revision.
Thesis (Ed.M.)--Boston Universityb1466393
Local Preferences and Place of Death in Regions within England 2010
This report shows public preferences for place of death in the nine English Government Office Regions (GORs), obtained from a population-based telephone survey in 2010. It compares the results with a similar survey carried out in 2003 to understand how preferences are evolving over time. It goes on to contrast these preferences with actual place of death (as reported for that region) in order to shed light on how people's wishes relate to reality and to aid care planning so that preferences are more frequently met
Palliative and End of Life Care for Black, Asian, and Minority Ethnic Groups in the UK
This report marks the start of a programme of work by many partners. A better understanding of the nation's changing demographics, of the needs of individual ethnic and cultural groups and of the types of services which will best meet their end of life care needs must be early outputs from the partnership. There are many areas which researchers will investigate further and many opportunities for service providers to work together with local communities to develop care which is sensitive and responsive to their needs as well as on a scale which will be needed for the large numbers of people who could benefi
First-principles study of crystallographic slip modes in ω-Zr.
We use first-principles density functional theory to study the preferred modes of slip in the high-pressure ω phase of Zr. The generalized stacking fault energy surfaces associated with shearing on nine distinct crystallographic slip modes in the hexagonal ω-Zr crystal are calculated, from which characteristics such as ideal shear stress, the dislocation Burgers vector, and possible accompanying atomic shuffles, are extracted. Comparison of energy barriers and ideal shear stresses suggests that the favorable modes are prismatic 〈c〉, prismatic-II [Formula: see text] and pyramidal-II 〈c + a〉, which are distinct from the ground state hexagonal close packed α phase of Zr. Operation of these three modes can accommodate any deformation state. The relative preferences among the identified slip modes are examined using a mean-field crystal plasticity model and comparing the calculated deformation texture with the measurement. Knowledge of the basic crystallographic modes of slip is critical to understanding and analyzing the plastic deformation behavior of ω-Zr or mixed α-ω phase-Zr
Entanglement from density measurements: analytical density-functional for the entanglement of strongly correlated fermions
We derive an analytical density functional for the single-site entanglement
of the one-dimensional homogeneous Hubbard model, by means of an approximation
to the linear entropy. We show that this very simple density functional
reproduces quantitatively the exact results. We then use this functional as
input for a local density approximation to the single-site entanglement of
inhomogeneous systems. We illustrate the power of this approach in a
harmonically confined system, which could simulate recent experiments with
ultracold atoms in optical lattices as well as in a superlattice and in an
impurity system. The impressive quantitative agreement with numerical
calculations -- which includes reproducing subtle signatures of the particle
density stages -- shows that our density-functional can provide entanglement
calculations for actual experiments via density measurements. Next we use our
functional to calculate the entanglement in disordered systems. We find that,
at contrast with the expectation that disorder destroys the entanglement, there
exist regimes for which the entanglement remains almost unaffected by the
presence of disordered impurities.Comment: 6 pages, 3 figure
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