10,719 research outputs found
Unemployment - its causes and remedies.
Thesis (M.A.)--Boston University
N.B.:Page 5 is mislabeled. No content is missing
Nested sampling for Potts models
Nested sampling is a new Monte Carlo method by Skilling [1] intended for general Bayesian computation. Nested sampling provides a robust alternative to annealing-based methods for computing normalizing constants. It can also generate estimates of other quantities such as posterior expectations. The key technical requirement is an ability to draw samples uniformly from the prior subject to a constraint on the likelihood. We provide a demonstration with the Potts model, an undirected graphical model
Farm Management - Bugger the roots, where is the future?
The Farm Management discipline has long been closely aligned with agricultural economics. The question we raise is not where either discipline came from but where is Farm Management going. The impact of globalisation, the rising tide of deregulation and chain reversal mean that farm management professionals who have traditionally focused on optimisation of activities at a farm level are now commonly expected to use sociology and management science to explain economic organisation and performance on farms. They also are required to look at relationships in the value chain(s) in which the farm sits. This paper will analyse the implications of such change for Farm Management professionals.Farm Management, value chains, Farm Management,
Narrow-line Laser Cooling by Adiabatic Transfer
We propose and demonstrate a novel laser cooling mechanism applicable to
particles with narrow-linewidth optical transitions. By sweeping the frequency
of counter-propagating laser beams in a sawtooth manner, we cause adiabatic
transfer back and forth between the ground state and a long-lived optically
excited state. The time-ordering of these adiabatic transfers is determined by
Doppler shifts, which ensures that the associated photon recoils are in the
opposite direction to the particle's motion. This ultimately leads to a robust
cooling mechanism capable of exerting large forces via a weak transition and
with reduced reliance on spontaneous emission. We present a simple intuitive
model for the resulting frictional force, and directly demonstrate its efficacy
for increasing the total phase-space density of an atomic ensemble. We rely on
both simulation and experimental studies using the 7.5~kHz linewidth S
to P transition in Sr. The reduced reliance on spontaneous
emission may allow this adiabatic sweep method to be a useful tool for cooling
particles that lack closed cycling transitions, such as molecules.Comment: 5 pages, 4 figure
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