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21.
国土资源数据分析及其整合与集成   总被引:4,自引:1,他引:3  
本文详细分析了国土资源数据特点、综合数据来源、产生方式和使用方法等方面,对数据进行了分类,比较了不同的数据格式。在此基础上,阐述了国土资源数据的集成框架,讨论了数据整合和集成的方法和流程,提出了数据整合与集成的三种框架问题。  相似文献   
22.
以时空数据模型及房产价格为研究对象,在同时满足基于特征和事件的空间时态数据模型基础上,结合数据库、统计分析、数据挖掘等技术创建基于位置(栅格)和对象(矢量)相结合的时空数据模型,实现了对马鞍山市房产价格的查询和管理.  相似文献   
23.
This paper proposes a novel history-matching method where reservoir structure is inverted from dynamic fluid flow response. The proposed workflow consists of searching for models that match production history from a large set of prior structural model realizations. This prior set represents the reservoir structural uncertainty because of interpretation uncertainty on seismic sections. To make such a search effective, we introduce a parameter space defined with a “similarity distance” for accommodating this large set of realizations. The inverse solutions are found using a stochastic search method. Realistic reservoir examples are presented to prove the applicability of the proposed method.  相似文献   
24.
张子扬 《现代测绘》2008,31(2):41-42
阐述了GIS系统的设计原则,建设方案,揭示了GIS系统功能模块的效能,利用Map控件建立信息管理系统,最后探讨了GIS系统在应用领域的发展前景。  相似文献   
25.
提出在数字化测图的外业编码数据采集过程中,对于未能连线的方向给与一个指向箭头,以便于在内业的地形图编辑中,根据指向箭头进行连线,提高连线率,减小外业作图工作量,提高工作效率。  相似文献   
26.
GPS-RTK联合全站仪的野外数据采集   总被引:1,自引:0,他引:1  
对于地形测绘和其它环境条件复杂的地区,用常规方法进行数据采集比较困难,传统的测绘方法越来越不能满足测量效率和成本的要求,但采用GPS RTK与全站仪联合作业,使RTK与全站仪优势互补,在保证测量精度的前提下,可大幅度提高测量速度和效率。  相似文献   
27.
NTRIP是一种播发实时差分定位改正信息的IP协议。本文讨论了NTRIP的组成、工作原理,并给出一个应用实例。  相似文献   
28.
Many decision-making processes in the Earth sciences require the combination of multiple data originating from diverse sources. These data are often indirect and uncertain, and their combination would call for a probabilistic approach. These data are also partially redundant with each other or with all others taken jointly. This overlap in information arises due to a variety of reasons—because the data arises from the same geology, because they originate from the same location or the same measurement device, etc. The proposed tau model combines partially redundant data, each taking the form of a prior probability for the event being assessed to occur given that single datum. The parameters of that tau model measure the additional contribution brought by any single datum over that of all previously considered data; they are data sequence-dependent and also data value-dependent. Data redundancy depends on the sequence in which the data is considered and also on the data values themselves. However, for a given sequence, averaging the tau model parameters over all possible data values leads to exact analytical expressions and corresponding approximations and inference avenues. Information on multiple-point connectivity of permeability arrives from core data, well-test data and seismic data which are defined over varying supports with complex redundancy between these information sources. In order to compute these tau weights for determining connectivity, one needs a model of data redundancy, here expressed as a vectorial training image (Ti) constructed using a prior conceptual knowledge of geology and the physics of data measurement. From such a vectorial Ti, the tau weights can be computed exactly. Neglecting data redundancy leads to an over-compounding of individual data information and the possible risk of making extreme decisions.  相似文献   
29.
The advent of the Virtual Observatory has begun an evolution in the space physics data environment. A number of nascent and discipline specific Virtual Observatories have started to emerge with an emphasis on data search and retrieval. As this new data environment takes shape an emphasis will be placed on interdisciplinary communication in attempts to address large scale and global problems. To this end we formulate the development of a query language to facilitate Virtual Observatory to Virtual Observatory communication. Furthermore, we outline the goals of such a language, how it would work and how existing community efforts can be leveraged to speed the development of this query language.
T.W. NarockEmail:
  相似文献   
30.
Numerical models are starting to be used for determining the future behaviour of seismic faults and fault networks. Their final goal would be to forecast future large earthquakes. In order to use them for this task, it is necessary to synchronize each model with the current status of the actual fault or fault network it simulates (just as, for example, meteorologists synchronize their models with the atmosphere by incorporating current atmospheric data in them). However, lithospheric dynamics is largely unobservable: important parameters cannot (or can rarely) be measured in Nature. Earthquakes, though, provide indirect but measurable clues of the stress and strain status in the lithosphere, which should be helpful for the synchronization of the models.The rupture area is one of the measurable parameters of earthquakes. Here we explore how it can be used to at least synchronize fault models between themselves and forecast synthetic earthquakes. Our purpose here is to forecast synthetic earthquakes in a simple but stochastic (random) fault model. By imposing the rupture area of the synthetic earthquakes of this model on other models, the latter become partially synchronized with the first one. We use these partially synchronized models to successfully forecast most of the largest earthquakes generated by the first model. This forecasting strategy outperforms others that only take into account the earthquake series. Our results suggest that probably a good way to synchronize more detailed models with real faults is to force them to reproduce the sequence of previous earthquake ruptures on the faults. This hypothesis could be tested in the future with more detailed models and actual seismic data.  相似文献   
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