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771.
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Masanori Sakamoto Kiyoji Shiono Shinji Masumoto Kiyoshi Wadatsumi 《Natural Resources Research》1993,2(2):140-147
In this article we describe the basic framework of the computerized geologic mapping system cigma. The system, whic is based on a mathematical formulation of geologic concepts, consists of the following six subsystems: (1) input of geologic data set; (2) inference of stratigraphic sequence; (3) construction of logical models of geologic structures; (4) determination of three-dimensional geologic boundary surfaces; (5) construction of three-dimensional solid model of geologic structures; and (6) graphical presentation. Geologic structures are summarized in several tables called logical models of geologic structures. Each model is constructed automatically from input data on structural relations between geologic bodies. The model interprets the data automatically to create data files necessary to determine the shapes of geologic boundaries; it also provides a threedimensional solid model of geologic structures referring to the shapes of boundaries. As a prototype, we introduce two types of contacts corresponding to conformity and unconformity into the logical model and show that it is possible to draw a geologic map automatically. More complex geologic structures can be introduced into the geologic mapping system through further formulation of geologic structures. 相似文献
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The logical tree methods are used for evaluate quantitatively relationship between frequency and magnitude, and deduce uncertainties
of annual occurrence rate of earthquakes in the periods of lower magnitude earthquake. The uncertainties include deviations
from the self-similarity of frequency-magnitude relations, different fitting methods, different methods obtained the annual
occurrence rate, magnitude step used in fitting, start magnitude, error of magnitude and so on. Taking Xianshuihe River source
zone as an example, we analyze uncertainties of occurrence rate of earthquakes M ≥ 4, which is needed in risk evaluation extrapolating from frequency-magnitude relations of stronger earthquakes. The annual
occurrence rate of M ≥ 4 is usually required for seismic hazard assessment.
The sensitivity analysis and examinations indicate that, in the same frequency-magnitude relations fitting method, the most
sensitive factor is annual occurrence rate, the second is magnitude step and the following is start magnitude. Effect of magnitude
error is rather small.
Procedure of estimating the uncertainties is as follows: (1) Establishing a logical tree described uncertainties in frequency-magnitude
relations by available data and knowledge about studied region. (2) Calculating frequency-magnitude relations for each end
branches. (3) Examining sensitivities of each uncertainty factors, amending structure of logical tree and adjusting original
weights. (4) Recalculating frequency-magnitude relations of end branches and complementary cumulative distribution function
(CCDF) in each magnitude intervals. (5) Obtaining an annual occurrence rate of M ≥ 4 earthquakes under given fractiles.
Taking fractiles as 20% and 80%, annual occurrence rate of M ≥ 4 events in Xianshuihe seismic zone is 0.643 0. The annual occurrence rate is 0.631 8 under fractiles of 50%, which is
very close to that under fractiles 20% and 80%. 相似文献
776.
在迎来中国数字地震台网运行10周年之际,9个台站设备的二期技术改造工作业已胜利完成。目前,这些台站配置了先进的计算机系统——SUN公司的SPARC系列台式工作站。其上安装了相应的地震分析软件,使得应用高质量的数字化数据进行地震分析成为可能,并弥补了模拟记录的许多不足。这无疑为台站工作人员及其它科研人员在台站现场进行地震分析工作,提供了十分便利的条件。但波形数据在SUN工作站上的驻留是一个动态的过程,一般只能保存3~4天,这给研究人员进行从容细致的应用分析造成了巨大的困难。本文着重介绍对这一问题的研究和解决方法。 相似文献
777.
The Ina district of the Ryoke Belt is divided into two mineral zones, based on the mineral parageneses of the pelitic and psammitic rocks at the peak metamorphism. A biotite–muscovite zone (quartz + plagioclase + biotite + muscovite with or without K-feldspar) constitutes the northwestern part, and a biotite–cordierite–K-feldspar zone (quartz + plagioclase + biotite + cordierite + K-feldspar) comprises the central to southern and eastern parts. The isograd reaction between two mineral zones is defined by a divariant reaction: Mg-rich biotite + muscovite + quartz = Fe-rich biotite + cordierite + K-feldspar + H2 O (1), which, in the K2 O–FeO–MgO–Al2 O3 –SiO2 –H2 O (KFMASH) system, occurs at ∼ 590 °C at 0.2 GPa and 660 °C at 0.4 GPa. Fibrolite accompanied by andalusite porphyroblasts in aluminous pelitic rocks of the biotite–muscovite zone and the low-grade part of the biotite–cordierite–K-feldspar zone, suggests that sillimanite was the stable aluminosilicate at the peak metamorphic condition throughout the area. In the high-grade part of the biotite–cordierite–K-feldspar zone, fibrolite mostly occurs as inclusions in cordierite or in plagioclase. The phase relations and the compositional zoning of plagioclase in relation to fibrolite inclusions suggest that fibrolite was formed under relatively high-pressure conditions, and that partial melting took place. 相似文献
778.
刘科友 《华东地质学院学报》1998,21(2):111-115
本文介绍应用铀,钍相关系数的统计检验法,来判断某两经岗岩侵入体的侵入关系。方法简便,准确度高。 相似文献
779.
旅游者行为规律与旅游地图编制关系的探讨 总被引:6,自引:1,他引:5
旅游者行为规律是旅游地理研究的一个方面,行,吃,住,游,娱,购行为是旅游者空间行为的重要方面,它与旅游地图有着双向导的密切关系,是旅游地图的主要内涵。旅游实施行为指导旅游地图编制,旅游地图为旅游者引导旅游实施行为,为其提供服务。因此,研究旅游者行为规律对旅游地图编制和产品开发有着重要意义。 相似文献
780.
复合地基沉降的复合本构有限元分析 总被引:27,自引:7,他引:20
提出了平面应变条件下复合地基沉降计算的复合本构有限元法。根据桩土界面处力的平衡条件和竖向变形协调条件,由桩、土材料各自的本构方程形成复合地基的本构方程,桩和桩周土可以采用任意非线性本构模型。工程实例分析表明,所建议的方法是有效的。 相似文献