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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 new paradigm for the U.S. economy?
Economic conditions - United States ; Business cycles
Endurance test and evaluation of alkaline water electrolysis cells
Utilization in the development of multi-kW low orbit power systems is discussed. The following technological developments of alkaline water electrolysis cells for space power application were demonstrated: (1) four 92.9 cm2 single water electrolysis cells, two using LST's advanced anodes and two using LST's super anodes; (2) four single cell endurance test stands for life testing of alkaline water electrolyte cells; (3) the solid performance of the advanced electrode and 355 K; (4) the breakthrough performance of the super electrode; (5) the four single cells for over 5,000 hours each significant cell deterioration or cell failure. It is concluded that the static feed water electrolysis concept is reliable and due to the inherent simplicity of the passive water feed mechanism coupled with the use of alkaline electrolyte has greater potential for regenerative fuel cell system applications than alternative electrolyzers. A rise in cell voltage occur after 2,000-3,000 hours which was attributed to deflection of the polysulfone end plates due to creepage of the thermoplastic. More end plate support was added, and the performance of the cells was restored to the initial performance level
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
Accurate Adiabatic Connection Curve Beyond the Physical Interaction Strength
The adiabatic connection curve of density functional theory (DFT) is
accurately calculated beyond the physical interaction strength for Hooke's
atom, two interacting electrons in a harmonic well potential. Extrapolation of
the accurate curve to the infinite coupling limit agrees well with the strictly
correlated electron (SCE) hypothesis but the approach to this limit is more
complex. The interaction strength interpolation is shown to be a good, but not
perfect, fit to the adiabatic curve. Arguments about the locality of
functionals and convexity of the adiabatic connection curve are examined in
this regime.Comment: 7 pages, 5 figure
Suicide substrate reaction-diffusion equations: varying the source
The suicide substrate reaction is a model for certain enzyme-inhibiting drugs. This reaction system is examined assuming that the substrate diffuses freely while the enzyme remains fixed. Two sets of initial and boundary conditions are examined: one modelling an instantaneous point source, akin to an injection of substrate, the other, a continuous point source, akin to a continuing influx, or intravenous drip, of substrate. The quasi-steady-state assumption is applied to obtain analytical solutions for a limited parameter space. Finally, further applications of numerical and analytical experimentation on pharmaceutical mechanisms are described
On the kinetics of suicide substrates
We consider a realistic suicide substrate reaction which can be represented by four rate equations for the concentrations of the various molecules as functions of time. We present a general procedure to obtain accurate, approximate solutions analytically in terms of the rate equation parameters. This systematic technique provides more accurate approximations to the exact (numerical) solutions than other approximate methods which have been proposed based on a pseudo-steady state hypothesis
Suppression of inelastic bound state resonance effects by the dimensionality of atom-surface scattering event
We develop a multidimensional coupled channel method suitable for studying
the interplay of bound state resonance and phonon assisted scattering of inert
gas atoms from solid surfaces in one, two and three dimensions. This enables us
to get insight into the features that depend on the dimensionality of inelastic
resonant processes typically encountered in low energy He atom scattering from
surfaces, in general, and to elaborate on the observability of recently
conjectured near threshold resonances in scattering from Einstein phonons, in
particular.Comment: 2 figure
Static Feed Water Electrolysis Subsystem Testing and Component Development
A program was carried out to develop and test advanced electrochemical cells/modules and critical electromechanical components for a static feed (alkaline electrolyte) water electrolysis oxygen generation subsystem. The accomplishments were refurbishment of a previously developed subsystem and successful demonstration for a total of 2980 hours of normal operation; achievement of sustained one-person level oxygen generation performance with state-of-the-art cell voltages averaging 1.61 V at 191 ASF for an operating temperature of 128F (equivalent to 1.51V when normalized to 180F); endurance testing and demonstration of reliable performance of the three-fluid pressure controller for 8650 hours; design and development of a fluid control assembly for this subsystem and demonstration of its performance; development and demonstration at the single cell and module levels of a unitized core composite cell that provides expanded differential pressure tolerance capability; fabrication and evaluation of a feed water electrolyte elimination five-cell module; and successful demonstration of an electrolysis module pressurization technique that can be used in place of nitrogen gas during the standby mode of operation to maintain system pressure and differential pressures
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