Field and numerical modelling studies for an efficient placement of roof bolts as breaker line support

Preliminary studies suggest that protein crystallization experiments using nanoliter-volume protein crystallization droplets may produce equal or better quality protein crystals compared with those grown using microliter volumes, and sometimes produce crystals in nanoliter volumes when microliter volumes are unable to produce diffraction-quality crystals. Computations and numerical modelling studies were performed to compare the influence of solutal convective disturbances around growing crystals and different drop volumes. These studies suggest that both crystal size and drop size contribute to a marked reduction in diffuso-convective disturbances in nanoliter drops and thus to the observed quality enhancements.

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Hydrodynamics and Theoretical Light Curves of SNe II

International Astronomical Union Colloquium ◽

10.1017/s0252921100007983 ◽

1996 ◽

Vol 145 ◽

pp. 119-128

Author(s):

V. S. Imshennik ◽

S. I. Blinnikov

Keyword(s):

Numerical Modelling ◽

Light Curves ◽

Modelling Studies

We discuss a new scenario for the production of SNII explosion and present the results of numerical modelling studies of SNe II light curves which are being done in our group.

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Numerical Modelling of Ballast Water Dispersion in Different Bioregions along the Coast of India

ASEAN Journal on Science and Technology for Development ◽

10.29037/ajstd.470 ◽

2018 ◽

Vol 35 (1-2) ◽

pp. 31-36

Author(s):

M.T. Babu ◽

K Sudheesh ◽

P Vethamony ◽

S Anuvindha

Keyword(s):

Numerical Modelling ◽

West Coast ◽

Ballast Water ◽

East Coast ◽

Marine Organisms ◽

Coastal Currents ◽

The West ◽

Water Dispersion ◽

Study Results ◽

Modelling Studies

Aquatic organisms and pathogens may become major threats to the coastal and marine environment when introduced into a region beyond their natural distributions through ballast water (BW). Coastal currents induced by tides and winds, especially ebb currents, may facilitate the spread of these marine organisms along nearshore and inshore areas. Numerical modelling of hydrodynamics is an effective tool to track the dispersion of these organisms in the receiving water body through BW release. Particle transport models can be used to track the advection and dispersion of these organisms. Alternatively, the difference in salinity of the BW and coastal waters can be used as a tracer to estimate the dispersion pattern. Tides and winds present in the region at the time of BW release are responsible for the dispersal of the particles present in BW discharge. Based on advection and dispersion processes, the transport of the marine organisms present in the BW can be studied using numerical models. Numerical modelling studies were carried out using the 2-D hydrodynamic model MIKE21 HD, to understand the pattern of BW dispersion at select bioregions along the east and west coasts of India. Mangalore Port located along the west coast in Bioregion-I (CIO-I) and Chennai Port on the east coast in Bioregion-II (CIO-II) were selected for the modelling study. Results obtained from ballast water dispersion modelling studies will be useful for developing and assisting port-based ballast water management programmes for CIO-I and CIO-II regions. The currents are predominantly tide driven near the ports situated along the west coast and the circulation exhibited reversals associated with the tidal currents. However, along the east coast of India, the particles largely followed coastal currents - advected either southward or northward under the influence of prevailing coastal currents in the offshore region and tidal reversals showed had less impact. This information proved useful for determining suitable locations for BW discharge and monitoring points for field sampling in connection with BW release.

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The deglaciation of the northwestern Laurentide Ice Sheet in the Mackenzie Mountains

10.5194/egusphere-egu2020-570 ◽

2020 ◽

Author(s):

Benjamin J. Stoker ◽

Martin Margold ◽

Duane G. Froese ◽

John C. Gosse

Keyword(s):

Numerical Modelling ◽

Last Glacial Maximum ◽

Ice Sheet ◽

Glacial Maximum ◽

Laurentide Ice Sheet ◽

Last Glacial ◽

Modelling Studies ◽

Mackenzie Mountains ◽

The Last Glacial Maximum ◽

The Last Glacial

The northwestern sector of the Laurentide Ice Sheet coalesced with the Cordilleran Ice Sheet over the southern Mackenzie Mountains, and with local montane glaciers along the eastern slopes of the Mackenzie Mountains. Recent numerical modelling studies have identified rapid ice sheet thinning in this region as a major contributor to Meltwater Pulse 1A. Despite advances in remote sensing and numerical dating methods, the configuration and chronology of the northwestern sector of the Laurentide Ice Sheet has not been reconstructed in detail. The last available studies date back to the 1990s, where field surveys and mapping from aerial imagery were used to reconstruct the Last Glacial Maximum glacier extents in the Mackenzie Mountains. Cross-cutting relationships between glacial landforms and a series of 36Cl cosmogenic nuclide dates were used to propose a deglacial model involving a significant ice readvance in the region. However, the chronological evidence supporting the readvance is uncertain because the individual ages are few and poorly clustered. Here we present an updated map of the Last Glacial Maximum glacial limits and the recessional record in the Mackenzie Mountains, based on glacial geomorphological mapping from the ArcticDEM. Sixteen new 10Be dates from four sites that were previously glaciated by the Laurentide Ice Sheet constrain the deglacial sequence across the region. These dates indicate ice sheet detachment from the eastern Mackenzie Mountains at ~16 ka as summits became ice-free. The Mackenzie Valley at ~ 65 &#176;N became ice free at ~ 13 &#8211; 14 ka, towards the end of the B&#248;lling-Aller&#248;d warm period. These chronological constraints on the deglaciation of the Laurentide Ice Sheet allow us to reinterpret landform relationships in the Mackenzie Mountains to reconstruct the ice sheet retreat pattern. Our updated model of the LGM extent and timing of deglaciation in the Mackenzie Mountains provides important constraints for quantifying past sea level contributions and numerical modelling studies.

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Submesoscale physical processes in the atmospheric boundary layer above fragmented sea ice.

10.5194/egusphere-egu2020-4980 ◽

2020 ◽

Author(s):

Marta Wenta ◽

Agnieszka Herman

Keyword(s):

Boundary Layer ◽

Numerical Modelling ◽

Sea Ice ◽

Atmospheric Boundary Layer ◽

Weather Prediction ◽

Heat Fluxes ◽

Physical Processes ◽

Sea Ice Extent ◽

Field Campaign ◽

Modelling Studies

In consequence of sea ice fragmentation in winter a range of physical processes take place between the sea/sea ice and the atmospheric boundary layer (ABL). Most of them occur on the level of individual ice floes and cracks and thus cannot be directly resolved by numerical weather prediction (NWP) models.&#160; Parametrizations of those processes aim to describe their overall effect on grid scale values, given the grid scale variables. However, as many of the processes taking place during winter sea ice fragmentation remain largely unrecognized they cannot be incorporated into the NWP models.&#160;The aim of the presented study is to determine whether the floe size distribution (FSD) has an effect on the ABL. Our previous research (Wenta, Herman 2018 and 2019) indicates that FSD might determine the intensity and spatial arrangement of convection and heat fluxes. A coefficient has been proposed for the correction of moisture heat flux, which can be incorporated into the NWP models. However, this research is based entirely on idealized model simulations and requires further modelling and observations based studies.In order to address this shortcoming, a field campaign is going to take place in the Bay of Bothnia in March 2020. Our goal is to create a 3D view of the atmosphere above fragmented sea and verify whether the processes and effects we found in the modeling results take similar form in real situations. Measurements results will be useful in the validation of our numerical modelling studies and will provide a unique dataset about the sea-ice-atmosphere interactions in the Bay of Bothnia area. Considering a significant decreasing trend in winter sea ice extent in the Baltic Sea it might contribute to our understanding of the role of ice in the local weather patterns. The field campaign is going to be complemented by numerical modelling with full version of Weather Research and Forecasting (WRF) model adjusted to the conditions over the Bay of Bothnia.&#160;Combined together - the results of our previous modelling studies and the results from the Bay of Bothnia field campaign, may considerably increase our knowledge about the surface-atmosphere coupling in the event of winter sea ice fragmentation.

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