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11.
Ken-Ichi Nishikawa Torsten Neubert Oscar Buneman 《Astrophysics and Space Science》1995,227(1-2):265-276
We have studied the solar wind-magnetosphere interaction using a 3-D electromagnetic particle code. The results for an unmagnetized solar wind plasma streaming past a dipole magnetic field show the formation of a magnetopause and a magnetotail, the penetration of energetic particles into cusps and radiation belt and dawn-dusk asymmetries. The effects of interplanetary magnetic field (IMF) have been investigated in a similar way as done by MHD simulations. The simulation results with a southward IMF show the shrunk magnetosphere with great particle entry into the cusps and nightside magnetosphere. This is a signature of a magnetic reconnection at the dayside magnetopause. After a quasi-stable state is established with an unmagnetized solar wind we switched on a solar wind with an northward IMF. In this case the significant changes take place in the magnetotail. The waving motion was seen in the magnetotail and its length was shortened. This phenomena are consistent with the reconnections which occur at the high latitude magnetopause. In our simulations kinetic effects will determine the self-consistent anomalous resistivity in the magnetopause that causes reconnections.Deceased January 24, 1993; R. Bunemanet al. 1993. 相似文献
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Policy-makers of some fossil fuel-endowed countries wish to know if a given fossil fuel supply project is consistent with the global carbon budget that would prevent a 2 °C temperature rise. But while some studies have identified fossil fuel reserves that are inconsistent with the 2 °C carbon budget, they have not shown the effect on fossil fuel production costs and market prices. Focusing on oil, we develop an oil pricing and climate test model to which we apply future carbon prices and oil consumption from several global energy-economy-emissions models that simulate the energy supply and demand effects of the 2 °C carbon budget. Our oil price model includes key oil market attributes, notably upper and lower market share boundaries for different oil producer categories, such as OPEC. Using the distribution of the global model results as an indicator of uncertainty about future carbon prices and oil demand, we estimate the probability that a new investment of a given oil source category would be economically viable under the 2 °C carbon budget. In our case study of Canada’s oil sands, we find a less than 5% probability that oil sands investments, and therefore new oil pipelines, would be economically viable over the next three decades under the 2 °C carbon budget. Our sensitivity analysis finds that if OPEC agreed to reduce its market share to 30% by 2045, a significant reduction from its steady 40–45% of the past 25 years, then the probability of viable oil sands expansion rises to 30%. 相似文献
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Acta Geotechnica - The hypoplastic model for sands proposed by Wolffersdorff (Mech Cohes Frict Mater 1: 251–271, 1996) combined with the intergranular strain anisotropy by Fuentes and... 相似文献
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Knittel Lukas Wichtmann Torsten Niemunis Andrzej Huber Gerhard Espino Edgar Triantafyllidis Theodoros 《Acta Geotechnica》2020,15(8):2075-2088
Acta Geotechnica - The elastic stiffness of a fine sand at small to moderate strains ( $$\varepsilon \le 2 \times 10^{-4}$$ ) has been studied based on cyclic triaxial tests on cube-shaped samples... 相似文献
17.
Guillaume Siron Lukas Baumgartner Anne‐Sophie Bouvier Benita Putlitz Torsten Vennemann 《Geostandards and Geoanalytical Research》2017,41(2):243-253
Five new biotite reference materials were calibrated at the SwissSIMS laboratory (University of Lausanne) for oxygen isotope determination by secondary ion mass spectrometry (SIMS) and are available to the scientific community. The oxygen isotope composition of the biotites, UNIL_B1 to B5, was determined by laser‐heating fluorination to be 11.4 ± 0.11‰, 8.6 ± 0.15‰, 6.1 ± 0.04‰, 7.1 ± 0.05‰ and 7.6 ± 0.04‰, respectively. SIMS analyses on spots smaller than 20 μm gave a measurement repeatability of 0.3‰ (2 standard deviation, 2s). The matrix effect due to solid solution in natural biotite could be expressed as a linear function of XMg and XF for biotite. No effect was found for different crystallographic orientations. SIMS analysis allows the oxygen isotope composition of biotite to be measured with a measurement uncertainty of 0.3–0.4‰ (2s) for biotites with similar major element compositions. A measurement uncertainty of 0.5‰ (2s) is realistic when F poor biotites (lower than 0.2% m/m oxides) within the compositional range of XMg of 0.3–0.9 were compared from different sessions. The linear correlation with F content offers a reasonable working curve for F‐rich biotites, but additional reference materials are needed to confirm the model. 相似文献
18.
Separation of time scales is used in a high cycle accumulation (HCA) model for sand. An important difficulty of the model is the limited applicability of the Miner’s rule to multiaxial cyclic loadings applied simultaneously or in a combination with monotonic loading. Another problem is the lack of simplified objective HCA formulas for geotechnical settlement problems. Possible solutions of these problems are discussed. 相似文献
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Hartmut H. Hellmer Monika Rhein Günther Heinemann Janna Abalichin Wafa Abouchami Oliver Baars Ulrich Cubasch Klaus Dethloff Lars Ebner Eberhard Fahrbach Martin Frank Gereon Gollan Richard J. Greatbatch Jens Grieger Vladimir M. Gryanik Micha Gryschka Judith Hauck Mario Hoppema Oliver Huhn Torsten Kanzow Boris P. Koch Gert König-Langlo Ulrike Langematz Gregor C. Leckebusch Christof Lüpkes Stephan Paul Annette Rinke Bjoern Rost Michiel Rutgers van der Loeff Michael Schröder Gunther Seckmeyer Torben Stichel Volker Strass Ralph Timmermann Scarlett Trimborn Uwe Ulbrich Celia Venchiarutti Ulrike Wacker Sascha Willmes Dieter Wolf-Gladrow 《Ocean Dynamics》2016,66(11):1379-1413
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Torsten Sander Philipp Wehner 《International journal of geographical information science》2013,27(6):799-819
Today's map navigation software offers more and more functionality. For example, it cannot only route from a start to a destination address, but the user can also specify a number of via destinations that are to be visited along the route. What is not commonly found in the software is the handling of so-called stopover areas. Here the user specifies a sequence of geographic areas and wants the route to lead into or through each of these areas (but he does not actually care where exactly). A modification of the well-known A☆ algorithm that considers convex stopover areas is presented. Algorithmic variants and implementation issues are discussed. Example results on a real-world data set are presented for the case of axis parallel rectangular stopover areas. 相似文献