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排序方式: 共有4521条查询结果,搜索用时 31 毫秒
731.
Inga Golbeck Xin Li Frank Janssen Thorger Brüning Jacob W. Nielsen Vibeke Huess Johan Söderkvist Bjarne Büchmann Simo-Matti Siiriä Olga Vähä-Piikkiö Bruce Hackett Nils M. Kristensen Harald Engedahl Ed Blockley Alistair Sellar Priidik Lagemaa Jose Ozer Sebastien Legrand Patrik Ljungemyr Lars Axell 《Ocean Dynamics》2015,65(12):1603-1631
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Natural Hazards - The accumulation of volatile organic compounds (VOCs) in ambient air affects air quality through the generation of surface level ozone and secondary organic aerosol. A study of... 相似文献
736.
V. M. Mishin A. D. Bazarzhapov U. Sukhbaatar M. Förster 《Geomagnetism and Aeronomy》2010,50(8):988-996
The simplest theory of electric circuits is applied to analysis of the observed large-scale electric field and currents in
a disturbed magnetosphere-ionosphere system. Maps of distribution of field-aligned currents (FACs) obtained from ground-based
magnetic measurements using the original magnetogram inversion method (MIT) and measurements by satellites were used. A method
for circuit determination according to the data of such maps based on the detection of spatial R.N inhomogeneities in each
of three Iijima and Potemra FAC zones is proposed. The results of the new method are used to describe some electric field
and current generators not known before, new types of current systems in tail lobes and plasma sheet, and the formation and
dynamics of new types of three-dimensional systems with auroral electrojets and meridional ionospheric Pedersen current, which
have not been paid due attention in the literature. 相似文献
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Passive seismic provides additional illumination sources in producing reservoirs, improving the Earth's imaging obtained by standard 3D seismic surveys. The joint tomographic inversion of surface and borehole data, both active and passive, even allows the delineation of thin reservoirs that cannot be resolved by reflection tomography. As an application example, we present a feasibility study for a real case of CO2 geological storage, showing that this operation may benefit both environment and reservoir monitoring. The origin time of micro‐earthquakes due to production operations is critical for merging active and passive data. We show here that the Wadati's method is not accurate for borehole data in a layered earth model, when the ratio between P and S velocities is not constant, as occurs in most hydrocarbon reservoirs. This drawback can be solved by deploying a few receivers at the surface close to the well. 相似文献
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Satellite services that deliver information about possible oil spills at sea currently use different labels of “confidence” to describe the detections based on radar image processing. A common approach is to use a classification differentiating between low, medium and high levels of confidence. There is an ongoing discussion on the suitability of the existing classification systems of possible oil spills detected by radar satellite images with regard to the relevant significance and correspondence to user requirements. This paper contains a basic analysis of user requirements, current technical possibilities of satellite services as well as proposals for a redesign of the classification system as an evolution towards a more structured alert system. This research work offers a first review of implemented methodologies for the categorisation of detected oil spills, together with the proposal of explorative ideas evaluated by the European Group of Experts on satellite Monitoring of sea-based oil Pollution (EGEMP). 相似文献
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