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941.
J. Aroba J. A. Grande J. M. Andújar M. L. de la Torre J. C. Riquelme 《Environmental Geology》2007,53(1):135-145
In this article, a set of clustering algorithms based on Fuzzy Logic and Data Mining are applied, allowing to obtain data
in the form of linguistic rules and charts about the behaviour of the Tinto and Odiel river estuary (SW Spain) affected by
Acid Mine Drainage (AMD). In order to provide researchers with no skills on data mining techniques an easy and intuitive interpretation,
we have developed a computer tool based on fuzzy logic that allows immediate qualitative analysis of the data contained in
a data from the estuary water chemical analyses, and serves as a contrast to functioning models previously proposed with classical
statistics. 相似文献
942.
This article provides a counter-narrative to the dominant discourse of marginalization and criminalization of Ghana’s illegal gold miners (galamsey) by focusing on the contested mercury debate. We first examine the complex and multifaceted policy problem that underlies the current conflictual aspects in the small-scale mining sector, arguing that mercury use and contamination are key elements in the antigalamsey rhetoric. Second, we describe an interdisciplinary pilot study on human and environmental health that involved health personnel and illegal miners from two sites. Through participatory ranking and mapping activities, we explored participants’ understanding of mercury and other life hazards as well as causes and consequences of mercury contamination. We used chemical indicator strips to sample contaminated areas in collaboration with the miners. By drawing upon novel concepts from the environmental justice and ecohealth literature, we propose a political ecology of human and environmental health that advocates recognition of galamsey operators and their participation in learning opportunities as a first step out of the current impasse in the Ghanaian small-scale mining sector. 相似文献
943.
随着地球重力场理论研究的发展,地球重力场的三维可视化成为需要,将数据挖掘技术应用于地球重力场三维可视化是一个新兴的研究领域。为此,提出了地球重力场可视化数据挖掘平台WHU-3Dgravity的设计与实现,并对其关键技术进行了分析。 相似文献
944.
滇西重力断层运动时间分布特征的初步研究 总被引:12,自引:11,他引:1
地表观测的重复重力数据综合反映了地表观测点的位置变化、地壳内部密度变化和地壳内部构造变形,通过反演这些数据得到的断层位错运动的时间变化综合反映了地壳内部形变和密度变化的耦合运动。为此,利用滇西1985年以来的重复重力观测数据,结合地质调查和地球物理推断结果确定断层运动模型作为约束,并考虑到观测数据和模型粗差,反演获得了滇西主要活动断裂运动的时间变化分布。结果表明,滇西1985-2001年断层运动的时间变化表现出断层往复运动特征,较好地反映了区内Ms≥6.0地震(如1996年丽江Ms7.0地震、1998年宁蒗Ms6.2地震和2000年姚安Ms6.5地震等)的孕育过程。指出强震孕育过程遵循地壳内部密度和地壳形变耦合运动模式(简称DD耦合运动模式),并给出了断层位错DD耦合运动模式的基本图像。 相似文献
945.
矿产资源定量评价工作的目的是从试验、观测、收集到的大量的各类专题数据中,提取相对应的专题信息。长期的地质工作积累了大量的原始数据,其中文本型的定性数据在地质数据中占了很大的分量,但是在常规的地质定量评价工作中针对这类数据的处理方法却很有限。文本型数据挖掘是现今数据挖掘的热点问题之一,为了充分利用前人所积累的文档报告,并有效地从中提取各类信息,这里提出了一种矿产地质数据库中文本数据挖掘的方法。在数据挖掘过程中,空间数据属性的小规模文本数据挖掘主要分四步进行,即数据挖掘相关的预处理;基于关键字的属性分解;属性归纳和关联规则分析。其中,挖掘关联规则问题可以分解为以下两个问题:1找出存在于数据库D中的所有频繁项集(或物品集)。频繁项集的支持度support应不小于用户或领域专家给定的最小支持度minsup阈值;2利用频繁项集生成强关联规则。根据定义,这些规则必须满足最小支持度minsup和最小可信度(置信度)minconf。对于每个频繁项集A,如BA,B,且Confidenceminconf,则构成关联规则B(A-B)。在文本的研究工作中开发了相应的软件系统,取得了较好的应用效果。属性数据是空间数据库的重要组成部分,它所荷载的专业方面的信息量是常规型数值数据所无法比拟的。如果能够进一步实现深层次属性数据挖掘,那么常规的信息源将得到极大的扩充,地质数据分析的层次也将会提升到一定的高度。 相似文献
946.
947.
C.J. Booth 《Environmental Geology》2006,49(6):796-803
Groundwater impacts are a common reason for opposition to longwall mining. Most impacts are due to subsidence-related fracturing.
Although upper aquifers are protected from drainage to the mine by a confining zone, water levels decline due to fracture
dilation, and drawdown expands outward a few hundred meters. Recovery of water levels is common. 相似文献
948.
黎政 《广东海洋大学学报》2006,26(2):103-107
《邓小平文选》是领导者语言的范例,存在大量的礼貌现象.体现着礼貌的思想。它们的运用可以给交际对方留面子,从而使交际活动更好地进行下去。以Brown和Levinson的面子保全论为理论基础,运用Leeoh的礼貌原则及六个次准则分析了《邓小平文选》领导语言中的各种礼貌的语言现象,其实现途径以及它的内在语用机制。这说明礼貌理论对文本交际活动也具有很强的阐释力。 相似文献
949.
文章通过对湖州市矿业经济发展简介,提出矿业开发促进了当地的经济发展,也造成了生态环境的破坏.对保护自然资源,保持生态环境,提出矿业综合治理措施的建议和措施. 相似文献
950.
Aquifer overexploitation: what does it mean? 总被引:9,自引:0,他引:9
Emilio Custodio 《Hydrogeology Journal》2002,10(2):254-277
Groundwater overexploitation and aquifer overexploitation are terms that are becoming common in water-resources management.
Hydrologists, managers and journalists use them when talking about stressed aquifers or some groundwater conflict. Overexploitation
may be defined as the situation in which, for some years, average aquifer abstraction rate is greater than, or close to the
average recharge rate. But rate and extent of recharge areas are often very uncertain. Besides, they may be modified by human
activities and aquifer development. In practice, however, an aquifer is often considered as overexploited when some persistent
negative results of aquifer development are felt or perceived, such as a continuous water-level drawdown, progressive water-quality
deterioration, increase of abstraction cost, or ecological damage. But negative results do not necessarily imply that abstraction
is greater than recharge. They may be simply due to well interferences and the long transient period that follow changes in
the aquifer water balance. Groundwater storage is depleted to some extent during the transient period after abstraction is
increased. Its duration depends on aquifer size, specific storage and permeability. Which level of "aquifer overexploitation"
is advisable or bearable, depends on the detailed and updated consideration of aquifer-development effects and the measures
implemented for correction. This should not be the result of applying general rules based on some indirect data. Monitoring,
sound aquifer knowledge, and calculation or modelling of behaviour are needed in the framework of a set of objectives and
policies. They should be established by a management institution, with the involvement of groundwater stakeholders, and take
into account the environmental and social constraints. Aquifer overexploitation, which often is perceived to be associated
with something ethically bad, is not necessarily detrimental if it is not permanent. It may be a step towards sustainable
development. Actually, the term aquifer overexploitation is mostly a qualifier that intends to point to a concern about the
evolution of the aquifer-flow system in some specific, restricted points of view, but without a precise hydrodynamic meaning.
Implementing groundwater management and protection measures needs quantitative appraisal of aquifer evolution and effects
based on detailed multidisciplinary studies, which have to be supported by reliable data.
Electronic Publication 相似文献