2,659 research outputs found
Tales of the City: A Study of Narrative and Urban Life
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136474/1/ae.2001.28.1.248.pd
The BBC: Guardian of Public Understanding
The British Broadcasting Corporation (BBC) is a long-standing institution with a worldwide reputation as the maker and supplier of trustworthy news embedded in programmes aimed at serving the public not commoditising it. This chapter describes the BBCâs institutional DNA and explains how its birth characteristics informed its institutional trajectory over the decades. The chapter discusses the internal principles and the particular âcraftâ that has made this a true British institution that has become equally revered outside Britainâs borders. It analyses how the BBC survived institutional crises to reach a moment in history where the very idea underlying this venerable but agile institution has come under fire
Simulations of Time-Resolved X-Ray Diffraction in Laue Geometry
A method of computer simulation of Time-Resolved X-ray Diffraction (TRXD) in
asymmetric Laue (transmission) geometry with an arbitrary propagating strain
perpendicular to the crystal surface is presented. We present two case studies
for possible strain generation by short-pulse laser irradiation: (i) a
thermoelastic-like analytic model; (ii) a numerical model including effects of
electron-hole diffusion, Auger recombination, deformation potential and thermal
diffusion. A comparison with recent experimental results is also presented.Comment: 9 pages, 11 figure
regulatory agency reputation acquisition:A Q Methodology analysis of the views of agency employees
This article reports findings of a Q Methodology study in which we explored the opinions of employees from eight Dutch regulatory agencies on how agencies gain their reputation. This is the largest study to date examining employee's views on the relative importance of different factors in reputation acquisition by public organizations, and the first analyzing employees in regulatory agencies. Results reveal five distinct âprofilesâ of opinion among employees about the factors most important in reputation acquisition. Regression analysis, further, supports that different regulatory agencies are dominated by employees with different opinions on how reputation is formed. These findings contribute to the growing empirical literature on how regulatory agencies, and their various employees, understand and approach reputation management.</p
regulatory agency reputation acquisition:A Q Methodology analysis of the views of agency employees
This article reports findings of a Q Methodology study in which we explored the opinions of employees from eight Dutch regulatory agencies on how agencies gain their reputation. This is the largest study to date examining employee's views on the relative importance of different factors in reputation acquisition by public organizations, and the first analyzing employees in regulatory agencies. Results reveal five distinct âprofilesâ of opinion among employees about the factors most important in reputation acquisition. Regression analysis, further, supports that different regulatory agencies are dominated by employees with different opinions on how reputation is formed. These findings contribute to the growing empirical literature on how regulatory agencies, and their various employees, understand and approach reputation management.</p
Optimization of inhomogeneous electron correlation factors in periodic solids
A method is presented for the optimization of one-body and inhomogeneous
two-body terms in correlated electronic wave functions of Jastrow-Slater type.
The most general form of inhomogeneous correlation term which is compatible
with crystal symmetry is used and the energy is minimized with respect to all
parameters using a rapidly convergent iterative approach, based on Monte Carlo
sampling of the energy and fitting energy fluctuations. The energy minimization
is performed exactly within statistical sampling error for the energy
derivatives and the resulting one- and two-body terms of the wave function are
found to be well-determined. The largest calculations performed require the
optimization of over 3000 parameters. The inhomogeneous two-electron
correlation terms are calculated for diamond and rhombohedral graphite. The
optimal terms in diamond are found to be approximately homogeneous and
isotropic over all ranges of electron separation, but exhibit some
inhomogeneity at short- and intermediate-range, whereas those in graphite are
found to be homogeneous at short-range, but inhomogeneous and anisotropic at
intermediate- and long-range electron separation.Comment: 23 pages, 15 figures, 1 table, REVTeX4, submitted to PR
Variational quantum Monte Carlo calculations for solid surfaces
Quantum Monte Carlo methods have proven to predict atomic and bulk properties
of light and non-light elements with high accuracy. Here we report on the first
variational quantum Monte Carlo (VMC) calculations for solid surfaces. Taking
the boundary condition for the simulation from a finite layer geometry, the
Hamiltonian, including a nonlocal pseudopotential, is cast in a layer resolved
form and evaluated with a two-dimensional Ewald summation technique. The exact
cancellation of all Jellium contributions to the Hamiltonian is ensured. The
many-body trial wave function consists of a Slater determinant with
parameterized localized orbitals and a Jastrow factor with a common two-body
term plus a new confinement term representing further variational freedom to
take into account the existence of the surface. We present results for the
ideal (110) surface of Galliumarsenide for different system sizes. With the
optimized trial wave function, we determine some properties related to a solid
surface to illustrate that VMC techniques provide standard results under full
inclusion of many-body effects at solid surfaces.Comment: 9 pages with 2 figures (eps) included, Latex 2.09, uses REVTEX style,
submitted to Phys. Rev.
Monte Carlo Simulations with Indefinite and Complex-Valued Measures
A method is presented to tackle the sign problem in the simulations of
systems having indefinite or complex-valued measures. In general, this new
approach is shown to yield statistical errors smaller than the crude Monte
Carlo using absolute values of the original measures. Exactly solvable,
one-dimensional Ising models with complex temperature and complex activity
illustrate the considerable improvements and the workability of the new method
even when the crude one fails.Comment: 10 A4 pages, postscript (140K), UM-P-93-7
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