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471.
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473.
Lucia Maria Seebach Peter Strobl Jesus San Miguel-Ayanz Annemarie Bastrup-Birk 《International journal of geographical information science》2013,27(11):1865-1884
Detailed and harmonized information on spatial forest distribution is an essential input for forest-related environmental assessments, in particular, for biomass and growing stock modeling. In the last years, several mapping approaches have been developed in order to provide such information for Europe in a harmonized way. Each of these maps exhibits particular properties and varies in accuracy. Yet, they are often used in parallel for different modeling purposes. A detailed spatial comparison seemed necessary in order to provide information on the advantages and limitations of each of these forest cover maps in order to facilitate their selection for modeling purposes. This article confronts the high-resolution forest cover map recently developed by the Joint Research Centre for the year 2000 (FMAP2000) with previously existing maps for the same time period: the CORINE Land Cover 2000 (CLC2000) and the Calibrated European Forest Map 1996 (CEFM1996). The spatial comparison of these three maps was carried out based on forest proportion maps of 1 km derived from the original maps. To characterize differences according to biogeographic regions, two criteria were used: detail of thematic content within each map and local spatial agreement. Concerning thematic content, CLC2000 displayed a surfeit of non-forested areas at the cost of low forest proportions, while FMAP2000 showed a more balanced distribution likely to preserve more detail in forest spatial pattern. Good spatial agreement was found for CLC2000 and FMAP2000 within about 70% of the study area, while only 50% agreement was found when compared with CEFM1996. The largest spatial differences between all maps were found in the Alpine and Mediterranean regions. Reasons for these might be different input data and classification techniques and, in particular, the calibration of CEFM1996 to reported national statistics. 相似文献
474.
Julian Hagenauer Marco Helbich 《International journal of geographical information science》2013,27(10):2026-2042
Spatial sciences are confronted with increasing amounts of high-dimensional data. These data commonly exhibit spatial and temporal dimensions. To explore, extract, and generalize inherent patterns in large spatiotemporal data sets, clustering algorithms are indispensable. These clustering algorithms must account for the distinct special properties of space and time to outline meaningful clusters in such data sets. Therefore, this research develops a hierarchical method based on self-organizing maps. The hierarchical architecture permits independent modeling of spatial and temporal dependence. To exemplify the utility of the method, this research uses an artificial data set and a socio-economic data set of the Ostregion, Austria, from the years 1961 to 2001. The results for the artificial data set demonstrate that the proposed method produces meaningful clusters that cannot be achieved when disregarding differences in spatial and temporal dependence. The results for the socio-economic data set show that the proposed method is an effective and powerful tool for analyzing spatiotemporal patterns in a regional context. 相似文献
475.
Ken Arroyo Ohori Hugo Ledoux Jantien Stoter 《International journal of geographical information science》2013,27(7):1166-1186
One solution to the integration of additional characteristics, for example, time and scale, into GIS data sets is to model them as extra geometric dimensions perpendicular to the spatial ones, creating a higher-dimensional model. While this approach has been previously described and advocated, it is scarcely used in practice because of a lack of high-level construction algorithms and accompanying implementations. We present in this paper a dimension-independent extrusion algorithm permitting us to construct from any (n–1)-dimensional linear cell complex represented as a generalised map, an n-dimensional one by assigning to each (n–1)-cell one or more intervals where it exists along the nth dimension. We have implemented the algorithm in C++11 using CGAL, made the source code publicly available and tested it in experiments using real-world 2D GIS data sets which were extruded to construct up to 5D models. 相似文献
476.
The goal of this article is to analyse several aspects of the construction of a unique project in cartography: the three-dimensional model of the city of Cadiz constructed between 1777 and 1779. Cadiz was the most important fortification in Spain at the time. We focus on new investigations of the two documentary sources relating to the construction of this maquette, or relief map, which hitherto have not been studied in conjunction. This approach facilitates an elucidation of the details of the production of the relief map that benefits from improved knowledge regarding materials, tools, construction techniques and the cost of preparing the model. Additionally, new conclusions are drawn regarding the true utility of maquettes at court and the possible causes of the sudden cancellation of this military project. 相似文献
477.
Rasha Deeb Kristien Ooms Veerle Van Eetvelde Philippe De Maeyer 《The Cartographic journal》2013,50(4):325-335
The main goal of this research is to investigate the influence of a map’s background colour on user preferences regarding labels’ typography, including their size, shape, orientation and texture. Four sets of backgrounds were tested: blank maps, grey scale, hot colours and cold colours. The foreground of these maps is populated with name labels, which are associated with point objects or areal objects. Bertin’s visual variables were applied to this set of name labels, both separately and in combination. User preferences of different typographic variations were registered and compared on the basis of different background colours using a one-way ANOVA. The results indicated that the typographic design of the map labels should not be adapted according to the map’s background colour. 相似文献
478.
Andrea Nanetti Angelo Cattaneo Siew Ann Cheong Chin-Yew Lin 《The Cartographic journal》2013,50(2):159-167
AbstractFor many years geological students have been graduating from universities with little knowledge of how to use the cartographic language of line, letter, symbol and tone by which the distribution and spatial arrangement of earth science data can be best expressed. The author discusses the development of the teaching of geological cartography in the Department of Earth Sciences at the University of Leeds. Details of this innovation are set against the background of data obtained from a recent questionnaire on the practice of cartography as a discipline in departments of geology in British universities. 相似文献
479.
none 《The Cartographic journal》2013,50(3):266-274
AbstractWhile graphic variables in 2D maps have been extensively investigated, 4D cartography is still a widely unexplored field. In this paper, we investigate the usefulness of 4D maps (three spatial dimensions plus time) for cartographically illustrating spatio-temporal environmental phenomena. The presented approach focuses mostly on explorative research rather than on enhancement and extension of existing methods and principles. The user study described in the paper shows that 4D cartography is not a well-explored research area and that many experienced map users try to apply their knowledge from 2D maps to 4D dynamic visualisations. Thus, in order to foster the discussion within the community, we formulated several basic research questions for the area of 4D cartography, which range from methods for representing time in 4D visualisations and understanding the temporal context to finding generic methods to achieve optimized temporal generalisation and a consistent definition of graphical variables for 3D and 4D. 相似文献
480.
Alexander J. Kent 《The Cartographic journal》2013,50(3):203-204
AbstractColour is considered a key means of expression for use in cartographic works. This is because colours and the relations among them influence not only the aesthetic impression a map creates but also its overall utility. In addition to Newton’s spectral colour theory, today theories with origins in artistic technique are gaining ground in cartography. This article introduces J. Itten’s colour theory (first published in 1961 in The Art of Colour [Kunst der Farbe]) with special attention given to his concept of seven colour contrasts. The article also discusses the suitability and unsuitability of their application in practical cartography, and it contributes original examples employing thematic maps, a discipline with broad possibilities for the application of these inventive methods by today’s mapmakers. 相似文献