Implementing the fast marching eikonal solver: spherical versus Cartesian coordinates   总被引：8，自引：0，他引：8  

Tariq Alkhalifah  Sergey Fomel† 《Geophysical Prospecting》2001,49(2):165-178

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Mathematical features of Hibler's model of large-scale sea-ice dynamics     

Eckhard Kleine  Sergey Sklyar 《Ocean Dynamics》1995,47(3):179-230

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Using sea-level data to constrain a finite-element primitive-equation ocean model with a local SEIK filter     

Lars Nerger  Sergey Danilov  Wolfgang Hiller  Jens Schröter 《Ocean Dynamics》2006,56(5-6):634-649

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Biosensors for marine pollution research,monitoring and control     

Kröger S  Piletsky S  Turner AP 《Marine pollution bulletin》2002,45(1-12):24-34

Measurement of ecological, climatic and anthropogenic changes underpins the formulation of effective management strategies for sustainable use and protection of the marine environment. Sensors are traditionally used in marine studies to determine physical parameters, but there is increasing demand for real-time information about chemical and biological parameters. These parameters are currently measured in samples collected at sea and subsequently analysed in the laboratory. Biosensors fuse the exquisite sensitivity and specificity of living systems with the processing power of microelectronics to deliver simple, inexpensive measurement systems for use in the field or deployment in situ. While their potential for use in the marine environment is enormous, much published work to date has focussed on applications in freshwater and wastewater. Marine applications pose a substantial challenge in the robustness required for remote application, but recent developments in portable medical devices and receptor design suggest that these demands can now be realistically tackled.  相似文献   

Dynamics of Global Climatic Changes and Possibility of Their Prediction Using Chemical Data from Greenland Ice     

Sergey R. Kotov 《Mathematical Geology》2003,35(4):477-491

Records from the Greenland Ice Sheet Project Two ice core are considered in terms of dynamical systems theory and nonlinear prediction. Dynamical systems theory allows us to reconstruct some properties of a phenomenon based only on past behavior without any mechanistic assumptions or deterministic models. A near-term prediction of temperature, including a mean estimate and confidence interval, is made for 800 years into the future. The prediction suggests that the present short-time global warming trend will continue for at least 200 years and be followed by a reverse in the temperature trend.  相似文献   

Role of water in the origin of podiform chromitite deposits   总被引：2，自引：0，他引：2  

Sergey Matveev  Chris Ballhaus 《Earth and Planetary Science Letters》2002,203(1):235-243

We report experiments in basalt oversaturated with water to duplicate the nodular ore textures of podiform chromitite ores. In immiscible basalt-water systems saturated with olivine and chromite, olivine will reside in the melt while chromite will collect in the fluid phase. Fractionation is physical and is driven by differential wetting properties of melt and fluid against silicate and oxide surfaces. There is no need to suppress olivine from the liquidus of a primitive basaltic melt as suggested by Irvine [Irvine, T.N., Geology 5 (1977) 273-277], to achieve chromite accumulations as observed in natural podiform ore deposits. The results imply that podiform chromitite ores will form where a primitive olivine-chromite-saturated mantle melt is sufficiently water-rich to exsolve a fluid phase during passage through the uppermost mantle. The most likely geodynamic environment for podiform chromite mineralization to take place is a supra-subduction zone setting.  相似文献   

Automated placement of supplementary contour lines     

Timofey Samsonov  Sergey Koshel  Dmitry Walther  Bernhard Jenny 《International journal of geographical information science》2019,33(10):2072-2093

Supplementary contour lines are placed between regular contour lines to visualize small but important forms that regular contour lines are unable to show. On topographic maps, typical forms are hillcrests, depressions, saddles, terraces, banks, and levees. No automated method for the selection of supplementary contour lines has been described so far. We document cartographic design principles for the selection of supplementary contour lines for topographic maps, and present an automated method for their placement. Results of the automated method are similar to manually placed supplementary contour lines. Our method helps map authors to create contour line maps that more effectively illustrate relevant small details in maps showing terrain elevation or other scalar fields.  相似文献   

Effective Rigidity of a Polar Neutron Monitor for Recording Ground-Level Enhancements     

Sergey A. Koldobskiy  Gennady A. Kovaltsov  Ilya G. Usoskin 《Solar physics》2018,293(7):110

The “effective” rigidity of a neutron monitor for a ground-level enhancement (GLE) event is defined so that the event-integrated fluence of solar energetic protons with rigidity above it is directly proportional to the integral intensity of the GLE as recorded by a polar neutron monitor, within a wide range of solar energetic-proton spectra. This provides a direct way to assess the integral fluence of a GLE event based solely on neutron-monitor data. The effective rigidity/energy was found to be 1.13?–?1.42 GV (550?–?800 MeV). A small model-dependent, systematic uncertainty in the value of the effective rigidity is caused by uncertainties in the low-energy range of the neutron-monitor yield function, which requires more detailed computations of the latter.  相似文献   

Composition and origin of holotype Al‐Cu‐Zn minerals in relation to quasicrystals in the Khatyrka meteorite          下载免费PDF全文

Marina A. Ivanova  Cyril A. Lorenz  Sergey E. Borisovskiy  Andrey A. Burmistrov  Dmitriy V. Korost  Alexander V. Korochantsev  Maria N. Logunova  Sergei I. Shornikov  Michail I. Petaev 《Meteoritics & planetary science》2017,52(5):869-883

We investigated the khatyrkite–cupalite holotype sample, 1.2 × 0.5 mm across. It consists of khatyrkite (Cu,Zn)Al₂, cupalite (Cu,Zn)Al, and interstitial material with approximate composition (Zn,Cu)Al₃. All mineral phases of the holotype sample contain Zn and lack Fe that distinguishes them from khatyrkite and cupalite in the Khatyrka meteorite particles (Bindi et al. 2009 , 2011 , 2012 , 2015 ; MacPherson et al. 2013 ; Hollister et al. 2014 ). Neither highly fractionated natural systems nor geo‐ or cosmochemical processes capable of forming the holotype sample are known so far. The bulk chemistry and thermal history of khatyrkite–cupalite assemblage in the holotype sample hint for its possible industrial origin. Likewise, the aluminides in the Khatyrka meteorite particles may also be derived from industrial materials and mixed with extraterrestrial matter during gold prospecting in the Listvenitovy Stream valley.  相似文献   

Mesoscale dynamics and walleye pollock catches in the Navarin Canyon area of the Bering Sea     

Andrey G. Andreev  Maxim V. Budyansky  Michael Yu. Uleysky  Sergey V. Prants 《Ocean Dynamics》2018,68(11):1503-1514

Large canyons incise the shelf break of the eastern Bering Sea to be preferred sites of the cross-shelf exchange. The mesoscale eddy activity is particularly strong near the shelf-break canyons. To study the mesoscale dynamics in the Navarin Canyon area of the Bering Sea, the time series of velocities derived from AVISO satellite altimetry between 1993 and 2015, drifters, Argo buoys, and ship-borne data are analyzed. We demonstrate that the strength of anticyclonic eddies along the shelf edge in spring and summer is determined by the wind stress in March–April. The increased southward wind stress in the central Bering Sea forced a supply of low-temperature and low-salinity outer shelf water to the deep basin and formation of the anticyclonic mesoscale circulation seaward of the Navarin Canyon. Enhanced northwestward advection of the Bering Slope Current water leads to increase in an ice-free area in March and April and increased bottom-layer temperature at the outer shelf. The strong (weak) northwestward advection of the eastern Bering Sea waters, determined by eastern winds in spring, creates favorable (unfavorable) conditions for the pollock abundance in the western Navarin Canyon area in summer.  相似文献