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911.
D. Skarlatos 《The Photogrammetric Record》1999,16(94):643-650
This paper investigates possible solutions to the problem of urban orthophotography. Extensive work has been carried out to attain the best possible results, using all the existing software in the Department of Geomatic Engineering, University College London. Two of the most promising methods, which yield the best results, are analysed further. New routines were written in C language, as additions to the existing software, to allow for the special problems that arise in urban areas. The final results overcome the problem of double mapping (or occlusions) and will potentially enable even greater success to be achieved. A simple accuracy assessment of the results has been made. Difficulties and current limitations are analysed and presented. 相似文献
912.
天津市空气污染数值预报试验中的模式系统 总被引:9,自引:1,他引:8
介绍了天津市空气污染数值预报实验中城市空气污染数值预报模式系统的构成及各模块的功能。在天津市空气污染预报实验期间, α中尺度气象模式对区域范围内的逐时风、温、湿及其降水预报取得了较好的效果, 且模式的计算时间短; β中尺度气象模式在边界层内具有较高的垂直分辨率, 模拟结果合理, 其中计算与观测的风向差小于60o的概率达到643% , 计算与观测的风速比值接近于1; 预报的地面SO2、NOx和TSP浓度与同步监测值相比, 城市空气污染预报模式对SO2和NOx的日平均浓度的预报效果较好, 预报准确率达640% , 而对TSP的预报则较差 相似文献
913.
914.
Budapest's built environment in transition 总被引:1,自引:0,他引:1
Alan Dingsdale 《GeoJournal》1999,49(1):63-78
The construction of major new buildings has been noticed in Budapest since the mid 1980s. New hotels, office blocks, housing
projects and most recently shopping centres have become a prominent feature of the landscape in several districts of the city.
The paper first outlines a conceptualisation of the `Transition' in terms of eastern Europe as a whole identifying internationalisation,
Europeanisation and national government policies as key strands in a specific case of a process of change interpreted as the
interaction of antecedent conditions and current processes. It then addresses the question of conceptualising the built environment
in terms of the `Transition' and three `schools of thought' in geography stressing the urban morphogenesis approach. It thus
poses the question of how radical a change has `occurred on the ground' since 1989–1990. Consequently the paper examines the
transition in the built environment of Budapest under three principal headings:
(a) the antecedent conditions of the built environment of Budapest by spatial structure,
(b) the relationship between new buildings and current processes,
(c) comparing models of the spatial structure of Budapest as a socialist city and as a post-socialist-(industrial) city or
post-industrial (capitalist) city.
It concludes that although the processes shaping the city's built environment have changed quite radically since 1990 the
physical fabric of the city and its antecedent usage have strongly influenced the spatial impact of the current processes.
Budapest is a post-socialist industrial city with capitalist forms fitted into it. The city is passing from socialist to capitalist
processes in a way that suggests that morphological analysis has clear potential in theorising the relationship between the
global and the local.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
915.
The developing countries at present have a high urban growth rate that is likely to continue for at least another quarter-century.
In addition, many of these urban centres are located in the Neogene plate boundary zones and are subject to multiple earthquake
and volcanic hazards. Slope failures and accelerated surface and channel erosion are particularly severe in cities near active
plate margins, and in areas affected also by tropical cyclones. We discuss two extreme cases: Singapore and Kingston (Jamaica).
Singapore is located in a stable environment and the urbanization related problems of flood and slope instability have been
reduced by proper building and drainage practices at a considerable cost. In Kingston, the external disturbances are repetitive,
large-scale, and very difficult to control. The fast-growing cities in the tropics need to be carefully monitored, especially
when located in an unstable physical environment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
916.
Luděk Sýkora 《GeoJournal》1999,49(1):79-89
The article overviews the most important changes in the internal urban structure of Prague since 1989. Post-communist urban
development has been influenced by government-directed reforms of political and economic system, internationalisation and
globalisation, public policies favouring unregulated market development, economic restructuring in terms of deindustrialisation
and growth of producer services, and increasing social differentiation. The three most transparent processes of urban change
in Prague have been (1) commercialisation of the historical core; (2) revitalisation of some inner city neighbourhoods; and
(3) residential and commercial suburbanisation in the outer city.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
917.
Omkar M. Shrestha Achyuta Koirala Jörg Hanisch Klaus Busch Martin Kerntke Stefan Jäger 《GeoJournal》1999,49(2):165-172
An engineering and environmental geological map of the Kathmandu Valley in Nepal has been elaborated within a project of German-Nepalese
cooperation. In the Kathmandu Valley, the major geo-environmental problems arise from haphazard exploitation of geologic resources,
local landslide zones, severe problems of garbage disposal, river flooding and a dramatic river pollution. The map was prepared
by the use of GIS techniques. It contains all basic geological and environmental data, as geotechnical risk zones (landslide-prone
areas or those of poor foundation conditions), areas for preferable extraction of construction material and those not to be
allowed to be exploited, areas of immediate need of reforestation in order to prevent landslide or badland development, groundwater
protection zones, and suitable garbage disposal sites.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
918.
城市垃圾性质及其填埋场的工程地质评价 总被引:10,自引:0,他引:10
王国强 《水文地质工程地质》1999,26(6):20-23
卫生填埋是现阶段处理城市垃圾的主要方法,正确评价,选择填埋垃圾的工程性质对填埋场的设计极为重要;填埋场是一个综合性污染源,若处理不当,会产生严重的环境工程地质问题,做好填埋场的工程地质研究,对于水资源及环境保护具有重要意义,本文对城市垃圾的工程性质进行了分析,评价,从环境工程地质学的角度对合肥市清溪路垃圾埋场的地基勘察,主要工程地质问题及应采取的工程措施进行了探讨。 相似文献
919.
在台风风暴增水过程中,风应力占主要作用,气压项的作用要上对较小,许多风暴潮预报模式中气压项被忽略。本文在建立台湾海峡风暴潮预报模型的基础上峄台风气压项作用进行了模拟,结果发现在台湾海峡狭长的海域内,台风气压项的作用表现得较为特殊,在台风风暴潮模拟过程中,应考虑其贡献及大小。 相似文献
920.
本文讨论1961 ̄1996年11月份福建省莆田地区出现暴雨过程的成因,分析表明暴雨的发生与南海东部沿海热带气旋(或低压)的例槽和北方冷空气共同影响密切相关,并讨论其形势特点、分析其物理量特征,同时进行对比分析。 相似文献