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911.
2006年美国国家科学基金会NSF首次提出CPS(Cyber-Physical Systems,CPS)概念。本文借助CPS概念、架构、特征,在对地震技术体系演进过程分析研究的基础上,提出构建地震4.0——新一代智能地震技术体系SCPS(Seismic–Cyber–Physical Systems)的创新理念,并对地震4.0的内涵、架构、平台和关键技术进行阐述和论证,期望推进地震技术体系的进一步发展。 相似文献
912.
Steven R. Long Ronald J. Lai Norden E. Huang Geoffry R. Spedding 《Dynamics of Atmospheres and Oceans》1993,20(1-2)
The blocking and trapping of waves and wave packets by inhomogeneous flow fields were studied in a laboratory setting. Evidence for multiple reflections and thus trapping within the current gradient zone near the blocking point are the main results obtained, and lead to the following conclusions: (1) a strong current gradient zone near the blocking point can trap wave energy, which will shift the wavenumbers into the capillary region, to match the microwave wavelength of many remote sensing instruments; (2) this mechanism provides a direct link between strong current gradient zones (bathymetric features in tidal flows, eddies, current boundaries, etc.) and the surface wave structure, which in turn allows instruments such as the Synthetic Aperture Radar (SAR) to form images of bottom features based solely on the small wave conditions; (3) an indication of direct energy transfer from the carrier waves to low-frequency waves was also observed, and resolved by wavelet analsysis. The instantaneous spectra from wavelet analysis reveal that a large portion of wave energy transfers directly into the low-frequency band from the carrier waves at the trapping zone. Subharmonics may play a critical role in the energy transfer process, but details are still to be established. 相似文献
913.
对湖南皂市水库库区及区域地壳运动、沉积建造以及浅部岩溶、古岩溶及深部岩溶作用作了较深入的研究与探讨,对与库区关系较密切的断裂及其活动性进行了考察,否定了沿主要库段南缘分布的袁公渡断裂.在上述工作基础上,认为水库区不存在诱发较大地震的地质条件,即使诱发较小有感地震,对大坝亦无影响。 相似文献
914.
R.K. Lowry S.J.B. Reed J. Nolan P. Henderson J.V.P. Long 《Earth and Planetary Science Letters》1981,53(1):36-40
An ion-microprobe-based technique has been used to measure lithium tracer-diffusion coefficients (DLi) in an alkali-basaltic melt at 1300, 1350 and 1400°C. The results can be expressed in the form:DLi=7.5 ×10?2exp(?27,600/RT)cm2S?1The results show significantly faster diffusion rates than those previously recorded for other monovalent, divalent and trivalent cations in a tholeiitic melt. Consequently, diffusive transport of ions acting over a given time in a basaltic melt can produce a wider range of transport distance values than hitherto supposed. Hence, it is concluded that great care should be exercised when applying diffusion data to petrological problems. 相似文献
915.
A theoretical model was developed to study the chemical speciation of the trace elements Zn, Cd, Cu and Pb aqueous solutions and their responses to variations in ionic strength and complexation. Two mixing solutions were investigated, a freshwater-seawater system and a freshwater-brine system. The brine was a calcium, sodium-chloride solution with a molal ionic strength of two. Trace element associations with the ligands OH?, Cl?, CO2?3, SO2?4, and HCO?3 were considered at pHs from 3.5 to 11.0 at 25°C. In general, the relative importance of the various ligand-trace element complexes can be predicted from a comparison of their stability constants. However, the effect of pH on the importance of a given complex is not readily apparent from the stability constants. Freshwater-seawater mixtures, as might be found in a totally mixed estuary, show that seawater composition is the dominant control on chemical complexing. Chloride complexing is similar for lead and zinc in the freshwater-brine mixtures. This similarity may account in part for the association of lead and zinc in strata-bound ore deposits. 相似文献
916.
917.
918.
J.H Vandermeulen D.E Buckley E.M Levy B.F.N Long P McLaren P.G Wells 《Marine pollution bulletin》1979,10(8):222-227
Weathering states of oil ranging from sheen oil to mousse have significant effects during oil stranding on oil-water and oil-sediment interaction. Observations of oiled sandy beaches suggest two mechanisms of beach contamination—general penetration and contamination of beach substrate by films of sheen oil (probably partially emulsified), and secondly the burial of discrete layers of mousse. Depending on timing of oiling with respect to beach dynamics large amounts of stranded oil can be accommodated within beach sediments. These then become available for later long-term release.Acute lethal toxicity of stranded Amoco Cadiz oil is intermediate to Bunker C and Kuwait crude. Simulated weathering studies suggest that there may be some increase in toxicity with weathering. 相似文献
919.
920.