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CARE: An integrated framework to support continuous, adaptable, reflective evaluation of egovernment systems: A research note
CARE: an Integrated Framework to Support Continuous, Adaptable, Reflective Evaluation of Egovernment SystemsThis is an eGISE network paper. It is motivated by a concern to develop a better approach to learning from the experience of an eGovernment project and applying that knowledge in future projects. The proposed project is based on previous work in the construction industry that developed COLA, a
Cross Organisational Learning Approach. Developing a similar strategy for Knowledge Management is likely to be effective because the ‘silo’ culture of local government organisations has parallels with the segmented organisational structures within the construction industry.Engineering and Physical Sciences Research Council, UK (grant GR/T27020/01
A combined R-matrix eigenstate basis set and finite-differences propagation method for the time-dependent Schr\"{od}dinger equation: the one-electron case
In this work we present the theoretical framework for the solution of the
time-dependent Schr\"{o}dinger equation (TDSE) of atomic and molecular systems
under strong electromagnetic fields with the configuration space of the
electron's coordinates separated over two regions, that is regions and
. In region the solution of the TDSE is obtained by an R-matrix basis
set representation of the time-dependent wavefunction. In region a grid
representation of the wavefunction is considered and propagation in space and
time is obtained through the finite-differences method. It appears this is the
first time a combination of basis set and grid methods has been put forward for
tackling multi-region time-dependent problems. In both regions, a high-order
explicit scheme is employed for the time propagation. While, in a purely
hydrogenic system no approximation is involved due to this separation, in
multi-electron systems the validity and the usefulness of the present method
relies on the basic assumption of R-matrix theory, namely that beyond a certain
distance (encompassing region ) a single ejected electron is distinguishable
from the other electrons of the multi-electron system and evolves there (region
II) effectively as a one-electron system. The method is developed in detail for
single active electron systems and applied to the exemplar case of the hydrogen
atom in an intense laser field.Comment: 13 pages, 6 figures, submitte
Half-Life of O
We have measured the half-life of O, a superallowed decay isotope. The O was produced by the
C(He,n)O reaction using a carbon aerogel target. A
low-energy ion beam of O was mass separated and implanted in a thin
beryllium foil. The beta particles were counted with plastic scintillator
detectors. We find s. This result is
higher than an average value from six earlier experiments, but agrees more
closely with the most recent previous measurement.Comment: 10 pages, 5 figure
Isolation of 39 polymorphic microsatellite loci and the development of a fluorescently labelled marker set for the Eurasian badger
We have isolated 78 microsatellite loci from the Eurasian badger (Meles meles). Of the 52 loci characterized, 39 were found to be polymorphic. A fluorescently labelled primer set was developed to enable individual-specific 17-locus genotypes to be obtained efficiently
Ejaculate allocation by male sand martins, Riparia riparia
Males of many species allocate sperm to ejaculates strategically in response to variation in the risk and intensity of sperm competition. The notable exception is passerine birds, in which evidence for strategic allocation is absent. Here we report the results of a study testing for strategic ejaculate allocation in a passerine bird, the sand martin (Riparia riparia). Natural ejaculates were collected from males copulating with a model female. Ejaculates transferred in the presence of a rival male contained significantly more sperm than ejaculates transferred in the absence of a rival male. There was no evidence that this difference was due to the confounding effects of the year of ejaculate collection, the identity of the model female, the colony, the stage of season or the period of the day in which ejaculates were collected. A more detailed examination of the ejaculate patterns of individual males, achieved by the DNA profiling of ejaculates, provided additional evidence for strategic allocation of sperm
On the density-potential mapping in time-dependent density functional theory
The key questions of uniqueness and existence in time-dependent density
functional theory are usually formulated only for potentials and densities that
are analytic in time. Simple examples, standard in quantum mechanics, lead
however to non-analyticities. We reformulate these questions in terms of a
non-linear Schr\"odinger equation with a potential that depends non-locally on
the wavefunction.Comment: 8 pages, 2 figure
Analysis of band-gap formation in squashed arm-chair CNT
The electronic properties of squashed arm-chair carbon nanotubes are modeled
using constraint free density functional tight binding molecular dynamics
simulations. Independent from CNT diameter, squashing path can be divided into
{\it three} regimes. In the first regime, the nanotube deforms with negligible
force. In the second one, there is significantly more resistance to squashing
with the force being nN/per CNT unit cell. In the last regime,
the CNT looses its hexagonal structure resulting in force drop-off followed by
substantial force enhancement upon squashing. We compute the change in band-gap
as a function of squashing and our main results are: (i) A band-gap initially
opens due to interaction between atoms at the top and bottom sides of CNT. The
orbital approximation is successful in modeling the band-gap opening at
this stage. (ii) In the second regime of squashing, large
interaction at the edges becomes important, which can lead to band-gap
oscillation. (iii) Contrary to a common perception, nanotubes with broken
mirror symmetry can have {\it zero} band-gap. (iv) All armchair nanotubes
become metallic in the third regime of squashing. Finally, we discuss both
differences and similarities obtained from the tight binding and density
functional approaches.Comment: 16 pages and 6 figures, To appear in PR
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