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301.
《International Journal of Digital Earth》2013,6(5):411-431
With growing demand on multi-purpose or multi-modal navigation, the route calculation needs to traverse semantically enriched road networks for different transportation modes. Currently, operational route planning algorithms reveal rather limited performances or their potential for comprehensive applications are constrained by the unavailable or insufficient interoperation among the underlying geo-data that are separately maintained in different spatial databases. To overcome this limitation, a novel approach has been proposed to integrate the routing-relevant information from different data sources, which involves three processes: (1) automatic matching to identify the corresponding road objects between different datasets; (2) interaction to refine the automatic matching result; and (3) transferring the routing-relevant information from one data-set to another. In process (1), the Delimited Stroke Oriented algorithm is employed to achieve the automatic data matching between different datasets, which has revealed a high matching rate and certainty. However uncertain matching problems occur in areas where topological conditions are too complicated or inconsistent. The remaining unmatched or wrongly matched objects are treated in process (2), with the help of a series of interaction tools. On the basis of refined matching results after the interaction, process (3) is dedicated to automatic integration of the routing-relevant information from different data sources. 相似文献
302.
《International Journal of Digital Earth》2013,6(9):901-922
ABSTRACTSpatial online analytical processing (OLAP) and spatial data warehouse (SDW) systems are geo-business intelligence technologies that enable the analysis of huge volumes of geographic data. In the last decade, the conceptual design and implementation of SDWs that integrate spatial data, which are represented using the vector model, have been extensively investigated. However, the integration of field data (a continuous representation of spatial data) in SDWs is a recent unresolved research issue. Enhancing SDWs with field data improves the spatio-multidimensional analysis capabilities with continuity and multiresolutions. Motivated by the need for a conceptual design tool and relational online analytical processing (ROLAP) implementation, we propose a UML profile for SDWs that integrates a regular grid of points and supports continuity and multiresolutions. We also propose an efficient implementation of a ROLAP architecture. 相似文献
303.
《International Journal of Digital Earth》2013,6(10):1070-1076
ABSTRACTIn this opinion paper, we, a group of scientists from environmental-, geo-, ocean- and information science, argue visual data exploration should become a common analytics approach in Earth system science due to its potential for analysis and interpretation of large and complex spatio-temporal data. We discuss the challenges that appear such as synthesis of heterogeneous data from various sources, reducing the amount of information and facilitating multidisciplinary, collaborative research. We argue that to fully exploit the potential of visual data exploration, several bottlenecks and challenges have to be addressed: providing an efficient data management and an integrated modular workflow, developing and applying suitable visual exploration concepts and methods with the help of effective and tailored tools as well as generating and raising the awareness of visual data exploration and education. We are convinced visual data exploration is worth the effort since it significantly facilitates insight into environmental data and derivation of knowledge from it. 相似文献
304.
随着城市规划信息化建设的不断深入与完善,GIS已成为一种辅助规划管理必不可少的新技术,怎样实现GIS与广泛使用的CAD之间的集成,成为当前规划信息化建设工作中必须解决的一项课题。本文以宁波市规划管理信息系统为例,实现了CAD与GIS、MIS系统的集成应用,对图文进行一体化管理。 相似文献
305.
针对分布式环境下区域分片片段间的各种原始缝隙,提出一种3RM(Three Relational Matrix)缝隙处理模型。该模型采用两阶段流程,第1步划分空间计算单元,对区域分片边界处的要素进行聚类分组;第2步对各个空间计算单元进行缝隙处理。模型研究区域分片边界处缝隙的描述和区分方法,依据要素拓扑关系、属性关系以及精度3种关系建立了3RM缝隙处理矩阵,发现线状和面状要素在分片数据边界处的38种潜在的缝隙,并建立了相应的缝隙处理方法。运用3RM模型对异构的土地利用分片数据进行缝隙处理试验,试验结果表明,本文提出的缝隙处理模型能够有效处理实际分片数据当中的各种缝隙。 相似文献
306.
The basic properties to be dealt with, when considering initially the research needs related to the integration of remote sensing (RS) information into a geographic information system (GIS), are many-sided. The primary combination of remote sensing and GIS is mainly realized by the transforms of data structure. Because of its own limitations, there is an urgent need to investigate the integration of RS and GIS in higher levels. In this paper, we discuss the different types of combinations of RS with GIS, and propose that GIS data should be directly brought into image processing from the beginning. A tentative idea of how to use the method of granularity to study the common processing unit of RS and GIS is described. The example for the determination of granularity of spatial data processing related to run-length-code line is also given. 相似文献
307.
AbstractUrban integration is an increasingly popular phenomenon. It is important to characterize the dynamic processes of urban integration from the perspective of geography. However, previous studies mainly focussed on the overall characteristics of a single entity and failed to consider inter-city influences. Therefore, this study aims to systematically investigate this phenomenon. Firstly, spatial clustering technique and landscape metric were used to analyze the temporal change of spatial layout. Secondly, we built multiple ring buffers of city boundary to reveal the directional differences in urban expansion. Lastly, we compared the observed land use data with the results simulated by cellular automata model. These experiments have shown that the urban expansion characteristics during the urban integration process are rather different from those of a single city, and the above methodology can effectively characterize the urban integration phenomenon. The successful example of Guangzhou–Foshan integration could also provide practical experience for other similar attempts. 相似文献
308.
309.
In the representation of topographic data, the distribution of hydrographic networks should be constrained by the contour model’s landform features. During the integration of topographic databases, however, spatial conflicts may destroy these constraints, generating inconsistencies. This study presents a method to detect and correct inconsistencies between river networks and contour data by spatial knowledge. First, structured terrain features are extracted from the contour-based geometric representation and matching relationships between rivers and contours are constructed based on spatial knowledge of the distribution of rivers and talwegs. We then propose a distance metric for measuring differences and identifying inconsistencies between the matched river and contour features. Three correction approaches are provided for different inconsistency situations, including river adjustment referenced to the contour, contour adjustment referenced to the river and adjustment of both river and contour to middle positions. We apply the proposed method to the integration and maintenance of national topographic infrastructure in order to demonstrate its effectiveness. 相似文献
310.