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991.
992.
Prediction of hydrocarbons in sedimentary basins 总被引:1,自引:0,他引:1
To estimate the undiscovered hydrocarbon potential of sedimentary basins, quantitative play assessments specific for each location in a region may be obtained using geostatistical methods combined with the theory of classification of geological objects, a methodology referred to as regionalization. The technique relies on process modeling and measured borehole data as well as probabilistic methods to exploit the relationship between geology (the predictor) and known hydrocarbon productivity (the target) to define prospective stratigraphic intervals within a basin. It is demonstrated in case studies from the oil-producing region of the western Kansas Pennsylvanian Shelf and the gas-bearing Rotliegend sediments of the Northeast German Basin. 相似文献
993.
Abstract Chelonioid sea turtles (Order Testudinata; Superfamily Chelonioidea) first appear in the early Cretaceous (Aptian-Albian). Their long fossil record is excellent compared to most marine tetrapods. Nonetheless, there has been no inclusive attempt to provide an analysis of cladistic relationships among this group. In this paper, the following chelonioid classification is proposed, based on 76 characters among 20 fossil and six living well- represented genera:
- 1 Family Cheloniidae (Coniacian to Recent); Toxochelys, Ctenochelys, Osteopygis, Erquelinnesia, Allopleuron, Argillochelys, Puppigerus, Eochelone, Syllomus, Natator, Eretmochelys, Chelonia, Caretta, Lepidochelys
- 2 Family Protostegidae (Aptian to Maastrichtian?); ‘Santana new protostegid’,Rhinochelys, Notochelone, Desmatochelys, Chelosphargis, Protostega, Archelon
- 3 Family Dermochelyidae (Santonian? to Recent); Corsochelys, ‘HMG new dermo-chelyid’, Eosphargis, Psephophorus, Dermochelys.
994.
Ecological classification of macrophytes and phytobenthos for rivers in Germany according to the water framework directive 总被引:9,自引:0,他引:9
Jochen Schaumburg Christine Schranz Julia Foerster Antje Gutowski Gabriele Hofmann Petra Meilinger Susanne Schneider Ursula Schmedtje 《Limnologica》2004,34(4):283-301
A new assessment system for macrophytes and phytobenthos in German rivers meeting the requirements of the Water Framework Directive (WFD) of the European Community is described. Biocoenotic types based on biological, chemical and hydromorphological data from over 200 river sites covering the main ecoregions, hydromorphological stream types and degradation forms have been defined. For developing a classification system the quality element macrophytes and phytobenthos was divided into three components: macrophytes, benthic diatoms and remaining phytobenthos. For macrophytes seven types including one subtype, for benthic diatoms 14 types including three subtypes and for the remaining phytobenthos five river types were identified. The benthic vegetation at reference condition was described for most of the river types. Degradation is characterised as deviation in benthic vegetation species composition and abundance from the reference biocoenosis. For classification in five ecological status classes, several metrics were developed and used in combination with existing indices. For some of the described river types additional investigations are necessary before a classification system can be developed. 相似文献
995.
基于Hopfield神经网络模型的遥感影像分类算法 总被引:1,自引:0,他引:1
针对遥感影像的分类特点,提出了一种基于Hopfield神经网络模型的遥感影像分娄算法。首先阐述了Hopfield神经网络的结构及其工怍原理,分析了Hopfield神经网络优化规则;然后在Hopfield神经网络通用模型基础上,实现了Hopfield神经网络的算法。实验结果表明,这种分类器具有较高的精度与效率,分类结果优于最大似然分类法。 相似文献
996.
Gennady Andrienko Natalia Andrienko Valeri Gitis 《ISPRS Journal of Photogrammetry and Remote Sensing》2003,57(5-6):380
This article considers two types of tools used for the analysis of spatial data: computational tools for grid data and visualization-based interactive exploratory techniques. The main purpose is to demonstrate that computational and visual techniques are complementary, and their combined use in data analysis may produce a synergistic effect. To this end, we describe two example scenarios of data analysis in the evaluation of potential damage from earthquakes and in analysis of forest resources. The analyses were performed with the use of CommonGIS, featuring the availability of powerful geocomputational tools and interactive visualization-related facilities that can be efficiently used in combination in a desktop environment or via the World Wide Web. 相似文献
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提出了一种基于自适应谐振理论建立起来的自组织模糊ARTMAP神经网络分类器。分析了ART神经网络的结构和工作原理,给出模糊ARTMAP神经网络分类的具体算法,并将其运用到TM遥感影像分类的实验中。结果表明模糊ARTMAP神经网络分类器的速度快,精度高,比常用的BP网络具有更好的性能。 相似文献
1000.
利用历史天气图资料,统计1960~2002年共42a桂林市10月暴雨天气过程,分析其影响天气系统环流特征及演变规律,分类建立预报模式指标,为10月暴雨实时预报业务提供一些参考。 相似文献