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31.
Heinrich Ebner Franz Müller Senlin Zhang 《ISPRS Journal of Photogrammetry and Remote Sensing》1989,44(4)
The paper investigates the capability of object reconstruction from space for two specific projects. Both of them are based on the use of three-line scanner systems allowing for simultaneous digital image recording from three different angles. An efficient model for combined point determination is proposed, considering the digital image data as well as orbit information, GPS and INS observations. The resulting accuracy is estimated from project oriented simulations. Finally, the possibilities for DTM generation, orthophoto production and stereo compilation from three-line scanner imagery are discussed. 相似文献
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Walter W. Loo Klaus Franz Gary R. Holzhausen 《Ground Water Monitoring & Remediation》1984,4(4):124-130
An advanced two-way radio link (transceiver units) and data logging system have provided a powerful means of real-time series data collection and analysis. The application of this telemetry system to surface tiltmeter surveys provides significant cost savings for testing and analysis of deep, large-scale horizontal anisotropic permeability and heterogeneity determinations.
The determination of horizontal anisotropic properties requires one pumping well and eight to 10 tiltmeter monitoring stations. The validity of the depth of the test may reach 4,000 feet below land surface. With the addition of one partially penetrating observation well, the entire three-dimensional anisotropic permeability can be determined. With the addition of a fully penetrating well, the storage coefficient can be determined as well as leakage property (including vertical permeability of the confining layers). An example test case was analyzed for horizontal anisotropic permeability with remarkable success despite relatively unfavorable detection conditions.
A thorough understanding of the geology overlying the aquifer system must be made in order to assess the applicability of the surface tiltmeter survey to large-scale horizontal anisotropic permeability determinations. 相似文献
The determination of horizontal anisotropic properties requires one pumping well and eight to 10 tiltmeter monitoring stations. The validity of the depth of the test may reach 4,000 feet below land surface. With the addition of one partially penetrating observation well, the entire three-dimensional anisotropic permeability can be determined. With the addition of a fully penetrating well, the storage coefficient can be determined as well as leakage property (including vertical permeability of the confining layers). An example test case was analyzed for horizontal anisotropic permeability with remarkable success despite relatively unfavorable detection conditions.
A thorough understanding of the geology overlying the aquifer system must be made in order to assess the applicability of the surface tiltmeter survey to large-scale horizontal anisotropic permeability determinations. 相似文献
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Mireille Christophe Michel-Lévy Gero Kurat Franz Brandstätter 《Earth and Planetary Science Letters》1982,61(1):13-22
The first meteoritic occurrence of CaAl4O7 is described from a Ca-Al-rich inclusion (CAI) in the Leoville carbonaceous chondrite. This CAI consists mainly of gehlenitic melilite, spinel, perovskite, and hibonite. CaAl4O7 is a minor component and occurs within melilite preferentially in portions rich in perovskite.The CAI is enveloped by a succession of three rims (from inside out): (a) hibonite+melilite+spinel+perovskite, (b) diopside, and (c) olivine.On the basis of mineral associations found and from the presence of moderately volatile elements (Fe and Cr) we conclude that the CaAl4O7-bearing CAI from Leoville is of residual nature. CaAl4O7 is apparently stable in the very Mg- and Si-poor environment of this CAI and is probably of igneous origin.The rims are interpreted as products of partial evaporation (rim (a)) and associated re-condensation (rims (b) and (c)). 相似文献
38.
Five samples from historical lava flows on Mt. Etna, which had previously been used in a palaeointensity study, were examined using a combination of rock magnetic and microscopic techniques to elucidate the causes of failure of palaeointensity determination. The samples were characterised using a combination of low-temperature susceptibility (LT-), Bitter pattern imaging and scanning electron microscope (SEM). High-temperature susceptibility curves and hysteresis loops had been previously measured by Calvo et al. (2001). Of the five samples only one gave an accurate palaeointensity. This sample was deuterically oxidised and consisted of large exsolved ore grains. It was only possible to distinguish this sample either optically or magnetically from a similar sample by the LT- warming curves; the unsuccessful sample displayed alteration in the LT- warming curves, which was not readily observed in the high temperature susceptibility curves. It is proposed that the measurement of LT- curves before and after heating could be a more sensitive method of determining suitability for palaeointensity determination than previous rock magnetic pre-selection techniques. 相似文献
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Franz Huber-Pock 《Meteorology and Atmospheric Physics》1960,12(1):17-23
Zusammenfassung In einer früheren Arbeit konnte gezeigt werden, daß das durchFjörtoft bei der graphischen Integration des barotropen Modells zur Rückermittlung des Isohypsenfeldes aus der Vorticityverteilung angewandte Näherungsverfahren, dem gewisse die Allgemeinheit einschränkende Voraussetzungen zugrunde liegen, durch eine statistische Methode mit Erfolg ersetzt werden kann. Der vorliegende Bericht beruht auf den gleichen statistischen Grundlagen, es kommen jedoch zusätzlich noch kinematische Überlegungen hinzu, die schließlich zu einer weiteren Vereinfachung des Arbeitsvorganges führen. Auswertungen an einer konkreten Wetterlage zeigen, daß sowohl die statistische wie die statistisch-kinematische Methode darüber hinaus eine gewisse Verbesserung der Resultate der Integration herbeiführen.
Mit 1 Textabbildung 相似文献
Summary In a previous paper it was shown that the computation of the geopotential field from a given vorticity distribution by means of theFjörtoft method of graphical integration of the barotropic model may be improved by the introduction of statistical considerations. The present paper deals with the same subject, however expanded by kinematical considerations which eventually lead to a further simplification of the routine procedure. The application to an actual weather situation indicates that the statistical as well as the statistical-kinematical method render a certain improvement of the results.
Résumé Dans une précédente étude, on avait montré que le processus d'approximation deFjörtoft permettant par intégration graphique de restituer le champ d'isohypses et qui supposait certaines restrictions, peut être remplacé avec succès par une méthode statistique. On ajoute ici à cette dernière des considérations d'ordre cinématique qui conduisent à simplifier encore le procédé. Un exemple pratique démontre que l'intégration proposée conduit à des résultats encore meilleurs.
Mit 1 Textabbildung 相似文献