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921.
922.
We have systematized the effects associated with climate change on urban spaces in Chile reported between 2000 and 2012. The method was based on a review of scientific articles in three databases (Scopus, Web of Knowledge and Scielo) using 32 keywords. Only 14 research papers were found related to climate change in urban spaces, most of which were case studies focused on the capital, Santiago. The main effects on urban spaces were found in four areas: (1) increase in temperature (heat islands, heat waves), (2) health problems in vulnerable populations (cardiac complications, heat stroke, and respiratory diseases), (3) increased demand for water, and (4) damage to the urban infrastructure with resulting risk to the population. In these circumstances the following measures are needed: (1) effective incorporation of the potential impacts of climate change into territorial planning instruments, (2) increased green areas to mitigate the impact of heat waves, (3) limiting of housing or public services in areas at risk, (4) encouraging the design of adaptation plans by involving the vulnerable population, and (5) implementing water conservation measures. We conclude that climate change is causing effects in urban areas that should be considered in the design and expansion of cities. 相似文献
923.
AbstractThe paper analyses the legal and regulatory instruments for water quality management that have been set in place in Singapore for control of water pollution, and their evolution since the time of independence in 1965. The role of institutions in the strict implementation of the laws and regulations is also discussed, with special emphasis on the efficient inter-institutional coordination machinery that has made it possible. The analyses show that overall long-term planning and policy-making and a strong political will have been instrumental to give all aspects of water management high priority in the national agenda, thus directly supporting urban, industrial and commercial growth.Editor Z.W. Kundzewicz 相似文献
924.
《International Journal of Digital Earth》2013,6(8):798-813
ABSTRACTCities often have a substantial green infrastructure, which provides local ecosystem services that improve the quality of life of urban residents. These services should be explicitly addressed in urban development policies, and areas with insufficient vegetation and limited access to public green spaces should be identified. This paper presents two spatially explicit urban green indicators that are derived using remote sensing imagery, freely available map data and spatial analysis tools from open source geospatial libraries and commercial software. The first indicator represents proportional green cover (public as well as private) in the vicinity of each building within a city. The second indicator quantifies the proximity of public green spaces as walking distances from buildings to actual park entrances. A dasymetric mapping approach was used to take spatial variations in population density into account. This allows representing the indicators from the perspective of citizens instead of buildings, which may be more meaningful for deriving statistics at city level or at the level of neighbourhoods or administrative zones. The potential use of these indicators in a planning context is discussed on a case study carried out for the city of Brussels, Belgium. 相似文献
925.
This paper aims to use spatial statistical tools to explore the reciprocal spatial–temporal effects of transport infrastructure and urban growth of Jeddah city, a fast developing polycentric city in Saudi Arabia. Global spatial autocorrelation (Moran's I) and local indicators of spatial association (LISA) are first used to analyze the spatial–temporal clustering of urban growth and transport infrastructure from 1980 to 2007. Then, spatial regression analysis is conducted to investigate the mutual spatial–temporal effects of urban growth and transport infrastructure. Results indicate a significant positive global spatial autocorrelation of all defined variables between 1980 and 2007. LISA results also reveal a constant significant spatial association of transport infrastructure expansion and urban growth variables from 1980 to 2007. The results not only indicate a mutual spatial influence of transport infrastructure and urban growth but also reveal that spatial clustering of transport infrastructure seems to be influenced by other factors. This study shows that transport infrastructure is a constant and strong spatial influencing factor of urban growth in the polycentric urban structure that Jeddah has. Overall, this study demonstrates that exploratory spatial data analysis and spatial regression analysis are able to detect the spatial–temporal mutual effects of transport infrastructure and urban growth. Further studies on the reciprocal relationship between urban growth and transport infrastructure using the study approach for the case of monocentric urban structure cities are necessary and encouraged. 相似文献
926.
This paper presents an approach to automated identification of slum area change patterns in Hyderabad, India, using multi-year and multi-sensor very high resolution satellite imagery. It relies upon a lacunarity-based slum detection algorithm, combined with Canny- and LSD-based imagery pre-processing routines. This method outputs plausible and spatially explicit slum locations for the whole urban agglomeration of Hyderabad in years 2003 and 2010. The results indicate a considerable growth of area occupied by slums between these years and allow identification of trends in slum development in this urban agglomeration. 相似文献
927.
In this study, a multi-scale approach was used for classifying land cover in a high resolution image of an urban area. Pixels and image segments were assigned the spectral, texture, size, and shape information of their super-objects (i.e. the segments that they are located within) from coarser segmentations of the same scene, and this set of super-object information was used as additional input data for image classification. The accuracies of classifications that included super-object variables were compared with the classification accuracies of image segmentations that did not include super-object information. The highest overall accuracy and kappa coefficient achieved without super-object information was 78.11% and 0.727%, respectively. When single pixels or fine-scale image segments were assigned the statistics of their super-objects prior to classification, overall accuracy increased to 84.42% and the kappa coefficient increased to 0.804. 相似文献
928.
主要从北京市规划委员会关于北京市城市轨道交通项目用地证核发方面的特殊要求探讨分析了北京市城市轨道交通项目拨地测量的可行性方法,明确了此类拨地测量不能完全参照常规的拨地测量方法进行作业,为此笔者从已经顺利完成拨地测量且证实方法可行的轨道交通线路上总结经验,本着避免造成用地浪费及保证用地范围合理性等诸多方面的考虑详细介绍了此类拨地测量的具体作业方法步骤及特殊要求,旨在能为北京市后续大批量的城市轨道交通项目拨地测量的作业人员提供有效指导,进而为规划部门提供合理准确的拨地成果进行用地审批,进一步体现测量在服务首都规划建设方面的积极作用。 相似文献
929.
Abstract Recent investigations demonstrated that inter‐year NOAA‐AVHRR NDVI variations at the middle of the rainy season can provide information on annual crop yields in Sahelian countries. This line of research is presently extended to the consideration of multitemporal NDVI data for several years (1986-1991) pre‐processed by a proven methodology. The investigation was conducted using NDVI and crop yield data from the sahelian sub‐districts of Niger. The results confirm that geographically standardized NDVI data are efficient for crop yield forecasting, but notable differences exist in this prediction capability depending on the beginning of the season. Late beginnings of the growing (rainy) season (after the end of June) allow optimum forecasting only after mid‐August, while early beginnings lead to anticipate the forecasting capability but also to decrease its accuracy. The importance of these findings in the context of an early warning system is finally discussed. 相似文献
930.
Eric Clark 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):83-91
Danish Journal of Geography 95: 83–91, 1995. The core of Stockholm's central business district, Lower Norrmalm, underwent a process of total renewal during the post-war period. This study asks if this renewal process may be interpreted as a manifestation of a logic of cyclicity inherent to the economies of regions and nations. First, time series over construction activity are presented for three geographic levels: Stockholm, the inner city and Lower Norrmalm. Then the observed booms and slumps are analyzed in the following contexts: construction activity on the national scale, transportation and urbanization, and finally, economic and spatial restructuring. Developments on Lower Norrmalm during this period seem to have been part of a regional and national building cycle, and were moulded by adaptation to transportation needs and rapid economic restructuring. But the local effects of these forces would have been very different were it not for the mediating and actively orchestrating roles assumed by local institutions. 相似文献