Wyniki wyszukiwania - BazTech

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eBalticGrid – an interactive platform for the visualisation of results from a high-resolution operational Baltic Sea model

Jakacki J., Przyborska A., Nowicki A., Wichorowski M., Przyborski M., Białoskórski M., Sochacki C., Tylman R.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2017

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Vol. 5, Iss. 2

13--20

EN

In recent years, modelling has been one of the fastest growing fields of science. Ocean, ice and atmospheric models have become a powerful tool that has supported many scientific fields during the last few decades. Our work presents the new operational service – called eBalticGrid – implemented into the PLGrid Infrastructure (Dziekoński et al. 2014). The grid is based on three modelling tools – an ocean model (Parallel Ocean Program), an ice model (Community Ice Code) and an atmospheric model (Whether Research and Forecasting Model). The service provides access to 72-hour forecasts for the Baltic Sea area. It includes the physical state of the Baltic Sea, its ice cover and the main atmospheric fields, which are the key drivers of the Baltic’s physical state. Unlike other services, this provides the additional three-dimensional fields of temperature, salinity and currents in the Baltic Sea. The models work in operational mode and currently one simulation per day is run. The service has been implemented mostly for researchers. Access to the results does not require any modelling knowledge. Therefore, the main interface between a user and the model results was designed as a portal providing easy access to the model’s output. It will also be a very suitable tool for teaching students about the hydrology of the Baltic Sea. Data from the system are delivered to another operational system – SatBaltic (Woźniak et al. 2011). The development of an output format to be suitable for navigational software (GRIB files) and sharing via FTP is also planned.

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Modelowanie molekularne w procesach mikro i nano obróbki

Musiał W., Rybicki J, Białoskórski M., Kordowska M.

Mechanik

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2013

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R. 86, nr 2CD

PL

W artykule przedstawiono możliwości realizacji symulacji molekularnych w odniesieniu do procesów nano i mikro wygładzania powierzchni obrabianych. Zaprezentowano również stanowisko badawcze do realizacji weryfikacji procesów skrawania pojedynczym ziarnem ściernym, które wyposażone zostało w zespół dosuwu nanometrycznego, umożliwiający realizacje dosuwu wgłębnego na poziomie atomowym

EN

This article presents the possibilities of realization of the molecular simulations in reference to processes the nano and the micropolishing of the worked surfaces. In article was presented also investigative position to realization of verification of cutting off processes with individual abrasive crystallite. This investigative position was equipped in nanometric in-feed set enabling in-feed realization on atomic level.

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Mechanical Properties of Single - walled Carbon Nanotubes Simulated with AIREBO Force - Field

Białoskórski M., Rybicki J.

Computational Methods in Science and Technology

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2012

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Vol. 18, No. 2

67-77

EN

In this work we determined the mechanical properties (Young's modulus, Poisson's ratio, and shear modulus) of 400 single-walled carbon nanotubes of radii from 2.1; ((0, 5) nanotube) to 17.3 A ((0, 45) nanotube). All nanotubes were simulated with AIREBO forcefield. It turns out that zigzag nanotubes are mechanically more resistant than armchair nanotubes.

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Structure recognition in MD-simulated materials. A case study of BO3 triangles in borate glasses

Bergmański G., Białoskórski M., Rychcik-Leyk M., Rybicki J.

Materials Science Poland

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2005

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Vol. 23, No. 4

989--999

EN

In computer simulations of the structure of matter, one usually obtains the Cartesian coordinates of all the particles involved. A non-trivial problem of structure recognition and characterization arises. In the present contribution, we study in detail the geometrical properties of a fuzzy-vertex CA3 structural unit (C - cation, A - anion). Two deformation degree estimators are introduced and examined. The Monte Carlo-generated stochastic characteristics of fuzzy CA3 triangles constitute conventional reference data that can be compared with the corresponding distributions calculated for a computer-simulated material. A quantitative estimation of the deformation degree of CA3 units in the simulated structure can thus be obtained. We apply the methods developed to quantitatively characterize the geometry of BO3 structural units in B2O3 glass.

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The structure of rarefied and densified PbSiO3 glass: a molecular dynamics study

Bergmański G., Białoskórski M., Rychcik-Leyk M., Witkowska A., Rybicki J., Mancini G., Frigio S., Feliziani S.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2004

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Vol. 8, No 3

393-412

EN

The paper is a molecular dynamics (MD) study of the structure of rarefied and densified lead-silicate glass of the PbSiO3 composition. Simulations have been performed in the constant volume regime for systems with densities of 3000, 4000, 5000, 5970 (normal density), 7000 and 8000kg/m3, using a two-body potential (Born-Mayer repulsive forces and Coulomb forces due to full ionic charges). All the systems were initially prepared as well equilibrated hot melts, and then slowly cooled down to 300K. The information on short-range correlations was obtained in a conventional way (from radial and angular distribution functions), while the middle-range order was studied via cation-anion ring analysis, using our new programme for basal ring determination. The structure of rarefied and densified glasses is compared with the structure of the same glasses under normal conditions. Moreover, the present results on PbSiO3 glass are compared with the corresponding data previously obtained for rarefied and densified PbGeO3 glass (Rybicki et al. 2001 Comput. Met. Sci. Technol. 7 91-112).

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The structure of porous and spontaneously densified amorphous PbSiO3 : a molecular dynamics study

Chomenko K., Bergmański G., Białoskórski M., Rychcik-Leyk M., Feliziani S., Frigio S., Witkowska A., Rybicki J.

Computational Methods in Science and Technology

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2004

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Vol. 10, nr 1

21-38

EN

In the paper we propose and test a "gel-drying" method of obtaining porous oxide glasses in Molecular Dynamics (MD) simulations. The simulation is started with low (screened) values of ionic charges. Then, the charges are gradually increased (to mimic the gradual elimination of a polar solvent) up to full ionic charges (a completely dry gel). This computational trick is applied to produce a porous PbSiO3 system. The structure of the resulting low-density samples is analysed in detail. Then, the porous structures are submitted to spontaneous densification, and the structure of the obtained dense bulk glasses is analysed. Finally, the structures of bulk glass obtained via spontaneous densification (density p - 8250 kg/m3) and bulk glass of the same density obtained via isotropic compression are compared.

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Molecular dynamics study of short and medium range order in modified BGO glasses

Walentynowicz A., Witkowska A., Białoskórski M., Rybicki J., Feliziani S., Frigio S., Cosimi G.

Computational Methods in Science and Technology

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2004

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Vol. 10, nr 2

203-218

EN

In the paper we present our recent Molecular Dynamics (MD) simulations of the structure of bismuth-germanate (BGO) glasses of x[pBi2 (1-p)Bi2O3](1-x)GeO2 composition, where x denotes the content of the bismuth oxide in unmodified glasses, and p - the fraction of neutral bismuth that can appear in the surface modification process (e.g, annealing in hydrogen atmosphere). We consider glasses of compositions x = 0.1, 0.2, 0.3 and reduction degrees = O, 0.25, 0.5, 0.75, 1. The simulation results are analysed in detail and compared with the structural data provided by other authors.