2,456 research outputs found
Modeling the effect of predicted sea-level rise on coastal conservation habitats using GIS
Global average temperatures have in
creased by about 0.6°C (± 0.2°C)
during the 20th century, and are project
ed to increase by 1.4 - 5.8°C by
2100 (IPCC, 2001a). The relationship
between atmospheric warming and
sea-level rise (SLR) is well understood,
and this change is predicted to lead
to SLR of up to 1m by 2100, cr
eating consequences for coastal
communities and environments
worldwide (IPCC, 2001b)
Coarsening dynamics of ternary amphiphilic fluids and the self-assembly of the gyroid and sponge mesophases: lattice-Boltzmann simulations
By means of a three-dimensional amphiphilic lattice-Boltzmann model with
short-range interactions for the description of ternary amphiphilic fluids, we
study how the phase separation kinetics of a symmetric binary immiscible fluid
is altered by the presence of the amphiphilic species. We find that a gradual
increase in amphiphile concentration slows down domain growth, initially from
algebraic, to logarithmic temporal dependence, and, at higher concentrations,
from logarithmic to stretched-exponential form. In growth-arrested
stretched-exponential regimes, at late times we observe the self-assembly of
sponge mesophases and gyroid liquid crystalline cubic mesophases, hence
confirming that (a) amphiphile-amphiphile interactions need not be long-ranged
in order for periodically modulated structures to arise in a dynamics of
competing interactions, and (b) a chemically-specific model of the amphiphile
is not required for the self-assembly of cubic mesophases, contradicting claims
in the literature. We also observe a structural order-disorder transition
between sponge and gyroid phases driven by amphiphile concentration alone or,
independently, by the amphiphile-amphiphile and the amphiphile-binary fluid
coupling parameters. For the growth-arrested mesophases, we also observe
temporal oscillations in the structure function at all length scales; most of
the wavenumbers show slow decay, and long-term stationarity or growth for the
others. We ascribe this behaviour to a combination of complex amphiphile
dynamics leading to Marangoni flows.Comment: 16 pages, 13 figures. Accepted for publication in Phys. Rev. E.
(Replaced for the latest version, in press.) Higher-quality figures can be
sent upon reques
MSUO Information Technology and Geographical Information Systems: Common Protocols & Procedures. Report to the Marine Safety Umbrella Operation
The Marine Safety Umbrella Operation (MSUO) facilitates the cooperation between Interreg
funded Marine Safety Projects and maritime stakeholders. The main aim of MSUO is to
permit efficient operation of new projects through Project Cooperation Initiatives, these
include the review of the common protocols and procedures for Information Technology (IT)
and Geographical Information Systems (GIS).
This study carried out by CSA Group and the National Centre for Geocomputation (NCG)
reviews current spatial information standards in Europe and the data management
methodologies associated with different marine safety projects.
International best practice was reviewed based on the combined experience of spatial data
research at NCG and initiatives in the US, Canada and the UK relating to marine security
service information and acquisition and integration of large marine datasets for ocean
management purposes.
This report identifies the most appropriate international data management practices that could
be adopted for future MSUO projects
A Particulate Basis for an Immiscible Lattice-Gas Model
We show that a phenomenological hydrodynamic lattice-gas model of two-phase
flow, developed by Rothman and Keller in 1988 and used extensively for
numerical simulations since then, can be derived from an underlying model of
particle interactions. From this result, we elucidate the nature of the
hydrodynamic limit of the Rothman-Keller model.Comment: 11 pages. Accepted for publication in Computer Physics Communication
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