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S. Heynisch A. Pekdeger B. Richter M. -Th. Schafmeister W. Skala 《Mathematical Geology》1994,26(4):505-517
Computer-based risk evaluation methods are practical tools to compare automatically and evaluate contaminated sites. HYDRISK is an example of adequate knowledge-based systems: HYDRISK evaluates hydrogeological properties and chemical criteria relevant to contaminant transport with respect to the necessary remedial actions. It works at a high investigative level and enables geologists and engineers to draw differentiated conclusions for selecting remediation methods for the contaminated site. HYDRISK emphasizes space and time dependent aspects of the contaminant transport. It is supported by a geographic information system (GIS) to display the evaluation results. Some ideas on considering the spatiotemporal variability of relevant parameters by means of geostatistical methods and numerical models will be given. 相似文献
44.
The Fourier transform infrared spectra of individual conodonts with various CAI values indicate definite changes in conodont francolite during diagenesis. Steady decarbonation can be observed in the increasing intensity of the band with the wavenumber 2340 an-1 , which is assigned to trapped molecular CO2 . Carbon dioxide originates from decomposing CO2- 3 -ions occupying the B-site in francolite. Furthermore, the intensity of the water-deformation band at 1644 cm-1 decreases with higher CAI values. These changes of intensity can be quantified by calculating the maximum extinction (Emax ) for the corresponding absorption maxima and correlated with the CAI. Unaltered conodonts have a relative variable water 'content' and very little CO2 . Up to a CAI value of 4 conodont francolite continuously expells water and carbon dioxide is trapped. Conodonts with CAI = 5 have similar water 'contents' to CAI = 4 conodonts, but decarbonation continues to take place during this stage of diagenesis. 相似文献
45.
When a satellite orbit decaying slowly under the action of air drag experiences 15th-order resonance with the Earth's gravitational field, so that the ground track repeats after 15 rev, the orbital inclination suffers appreciable changes due to the perturbations from the harmonics in the geopotential of order 15 and odd degree (15,17,19 …). In this paper the changes in inclination at resonance of 11 satellites at inclinations between 30° and 90° have been analysed to determine values of the geopotential coefficients of order 15 and degree and in the usual notation. The recommended solution, going up to l = 31, is:
l | 109C?l,15 | 109S?l,15 |
15 | ?21.5 ± 0.9 | ?8.4 ± 0.9 |
17 | 4.4 ± 1.6 | 9.0 ± 1.5 |
19 | ?15.6 ± 2.6 | ?14.1 ± 2.7 |
21 | 10.4 ± 3.0 | 7.3 ± 3.5 |
23 | 22.5 ± 2.8 | 1.2 ± 4.4 |
25 | ?0.9 ± 4.7 | ?3.8 ± 5.3 |
27 | ?11.2 ±3.3 | 9.1 ± 3.2 |
29 | ?20.5 ± 5.4 | ?1.2 ± 6.1 |
31 | 17.7 ± 6.6 | ?1.0 ± 7.1 |