1,366 research outputs found
Adaptation of NEMO-LIM3 model for multigrid high resolution Arctic simulation
High-resolution regional hindcasting of ocean and sea ice plays an important
role in the assessment of shipping and operational risks in the Arctic Ocean.
The ice-ocean model NEMO-LIM3 was modified to improve its simulation quality
for appropriate spatio-temporal resolutions. A multigrid model setup with
connected coarse- (14 km) and fine-resolution (5 km) model configurations was
devised. These two configurations were implemented and run separately. The
resulting computational cost was lower when compared to that of the built-in
AGRIF nesting system. Ice and tracer boundary-condition schemes were modified
to achieve the correct interaction between coarse- and fine grids through a
long ice-covered open boundary. An ice-restoring scheme was implemented to
reduce spin-up time. The NEMO-LIM3 configuration described in this article
provides more flexible and customisable tools for high-resolution regional
Arctic simulations
Revealing sub-{\mu}m inhomogeneities and {\mu}m-scale texture in H2O ice at Megabar pressures via sound velocity measurements by time-domain Brillouin scattering
Time-domain Brillouin scattering technique, also known as picosecond
ultrasonic interferometry, which provides opportunity to monitor propagation of
nanometers to sub-micrometers length coherent acoustic pulses in the samples of
sub-micrometers to tens of micrometers dimensions, was applied to
depth-profiling of polycrystalline aggregate of ice compressed in a diamond
anvil cell to Megabar pressures. The technique allowed examination of
characteristic dimensions of elastic inhomogeneities and texturing of
polycrystalline ice in the direction normal to the diamond anvil surfaces with
sub-micrometer spatial resolution via time-resolved measurements of variations
in the propagation velocity of the acoustic pulse traveling in the compressed
sample. The achieved two-dimensional imaging of the polycrystalline ice
aggregate in-depth and in one of the lateral directions indicates the
feasibility of three-dimensional imaging and quantitative characterization of
acoustical, optical and acousto-optical properties of transparent
polycrystalline aggregates in diamond anvil cell with tens of nanometers
in-depth resolution and lateral spatial resolution controlled by pump laser
pulses focusing.Comment: 32 pages, 5 figure
Hydrocortisone concentration influences time to clinically significant healing of acute inflammation of the ocular surface and adnexa – results from a double-blind randomized controlled trial
BACKGROUND: The efficacy of topical ophthalmic corticosteroids depends upon small modifications in preparations, such as drug concentration. The aim of this study was to confirm that hydrocortisone acetate (HC-ac) ophthalmic ointments of 2.5% and 1% are more effective than a 0.5% eye ointment. METHODS: In this randomized, double-blind, placebo-controlled, parallel-group clinical study, the change of signs and symptoms of acute inflammation of the ocular surface and adnexa was evaluated in 411 subjects. RESULTS: Median time to clinically relevant response as estimated by 50% reduction in clinical signs and symptoms (CSS) total score over the entire trial was similar for subjects treated with HC-ac 2.5% (73.5 h) and for subjects treated with HC-ac 1.0% (67.7 h) and was considerably and significantly longer for subjects treated with HC-ac 0.5% (111.8 h) [p < 0.001 for both dosages]. All trial medications were safe and well tolerated. CONCLUSION: Hydrocortisone acetate 2.5% and Hydrocortisone acetate 1% eye ointments are efficacious and safe treatments for acute inflammations of the ocular surface or adnexa, and showed significantly better efficacy than a control group treated with Hydrocortisone acetate 0.5% therapy. TRIAL REGISTRATION: Current Controlled Trials ISRCTN15464650
A Conceptual Approach to Complex Model Management with Generalized Modelling Patterns and Evolutionary Identification
Complex systems' modeling and simulation are powerful ways to investigate a
multitude of natural phenomena providing extended knowledge on their structure
and behavior. However, enhanced modeling and simulation require integration of
various data and knowledge sources, models of various kinds (data-driven
models, numerical models, simulation models, etc.), intelligent components in
one composite solution. Growing complexity of such composite model leads to the
need of specific approaches for management of such model. This need extends
where the model itself becomes a complex system. One of the important aspects
of complex model management is dealing with the uncertainty of various kinds
(context, parametric, structural, input/output) to control the model. In the
situation where a system being modeled, or modeling requirements change over
time, specific methods and tools are needed to make modeling and application
procedures (meta-modeling operations) in an automatic manner. To support
automatic building and management of complex models we propose a general
evolutionary computation approach which enables managing of complexity and
uncertainty of various kinds. The approach is based on an evolutionary
investigation of model phase space to identify the best model's structure and
parameters. Examples of different areas (healthcare, hydrometeorology, social
network analysis) were elaborated with the proposed approach and solutions
Classicality concept test on neutral pseudoscalar meson qubits with Wigner inequalities
In this study, we introduce the concept of Classicality and derive Wigner
inequalities that depend on two instants, with a potential extension to three
instants. We explore the experimental feasibility of testing the violations of
these inequalities in both pure and mixed flavor states of -, -, and
- meson pairs. Using the Werner noise model, we demonstrate that
violations of time-dependent Wigner inequalities can be detected even when
background processes constitute up to 50% of the system
Surrogate Modelling for Sea Ice Concentration using Lightweight Neural Ensemble
The modeling and forecasting of sea ice conditions in the Arctic region are
important tasks for ship routing, offshore oil production, and environmental
monitoring. We propose the adaptive surrogate modeling approach named LANE-SI
(Lightweight Automated Neural Ensembling for Sea Ice) that uses ensemble of
relatively simple deep learning models with different loss functions for
forecasting of spatial distribution for sea ice concentration in the specified
water area. Experimental studies confirm the quality of a long-term forecast
based on a deep learning model fitted to the specific water area is comparable
to resource-intensive physical modeling, and for some periods of the year, it
is superior. We achieved a 20% improvement against the state-of-the-art
physics-based forecast system SEAS5 for the Kara Sea.Comment: 7 pages, 6 figure
Hunting, Fishing and Early Agriculture in Northern Primor'e in the Russian Far East
departmental bulletin pape
Surrogate-Assisted Evolutionary Generative Design Of Breakwaters Using Deep Convolutional Networks
In the paper, a multi-objective evolutionary surrogate-assisted approach for
the fast and effective generative design of coastal breakwaters is proposed. To
approximate the computationally expensive objective functions, the deep
convolutional neural network is used as a surrogate model. This model allows
optimizing a configuration of breakwaters with a different number of structures
and segments. In addition to the surrogate, an assistant model was developed to
estimate the confidence of predictions. The proposed approach was tested on the
synthetic water area, the SWAN model was used to calculate the wave heights.
The experimental results confirm that the proposed approach allows obtaining
more effective (less expensive with better protective properties) solutions
than non-surrogate approaches for the same time
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