Geopotential harmonics of order 15 and 30, from analysis of the orbit of satellite 1971-10B     

Doreen M.C. Walker 《Planetary and Space Science》1985,33(1):97-107

The satellite 1971-10B passed through exact 15th-order resonance on 30 March 1981 and orbital parameters have been determined at 52 epochs from some 3500 observations using the RAE orbit refinement program, PROP, between September 1980 and October 1981. The variations in inclination and eccentricity during this time have been analysed, and six lumped 15th-order harmonic coefficients and two 30th-order coefficients have been evaluated. The 15th-order coefficients are the best yet obtained for an orbital inclination near 65°; and previously there were no 30th-order coefficients available at this inclination. The lumped coefficients have been used to test the Goddard Earth Model GEM 10B: there is good agreement for seven of the eight coefficients.  相似文献   

Geology and metal contents of the Ruttan volcanogenic massive sulfide deposit, northern Manitoba, Canada     

C. Tucker Barrie  Craig Taylor  Doreen E. Ames 《Mineralium Deposita》2006,41(8):837-837

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Redox-dependent removal of 27 organic trace pollutants: compilation of results from tank aeration experiments     

Victoria Burke  Doreen Richter  Ulrike Hass  Uwe Duennbier  Janek Greskowiak  Gudrun Massmann 《Environmental Earth Sciences》2014,71(8):3685-3695

The biodegradation of various wastewater-derived organic trace pollutants occurring in different aquatic compartments of the environment was previously reported to be influenced by the prevailing redox conditions. However, comparative studies on the redox-dependent degradation behavior of organic trace pollutants are scarce. The objective of the study presented herein, was to compile and evaluate data from several comparable previous tank experiments, thus, providing an overview on the redox-dependent removal of a total of 27 wastewater-derived trace compounds, including phenazone type compounds, antimicrobials, ß-blockers, psychoactive drugs and sulfonamides. Removal rate constants were fitted assuming first-order degradation kinetics. Six compounds were identified to be removed solely under oxic, three compounds solely under anoxic conditions. Others persisted under all experimental conditions, while some were removed under both oxic and anoxic conditions.  相似文献   

Fuzzy mapping of tropical land cover along an environmental gradient from remotely sensed data with an artificial neural network   总被引：1，自引：0，他引：1  

Giles M. Foody  Doreen S. Boyd 《Journal of Geographical Systems》1999,1(1):23-35

Remote sensing is the only feasible means of mapping and monitoring land cover at regional to global scales. Unfortunately the maps are generally derived through the use of a conventional 'hard' classification algorithm and depict classes separated by sharp boundaries. Such approaches and representations are often inappropriate particularly when the land cover being represented may be considered to be fuzzy. The definition of boundaries between classes can therefore be difficult from remotely sensed data, particularly for continuous land cover classes which are separated by a fuzzy boundary which may also vary spatially in time. In this paper a neural network was used to derive fuzzy classifications of land cover along a transect crossing the transition from moist semi-deciduous forest to savanna in West Africa in February and December 1990. The fuzzy classifications revealed both sharp and gradual boundaries between classes located along the transect. In particular, the fuzzy classifications enabled the definition of important boundary properties, such as width and temporal displacement.  相似文献