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基于GIS的远程移动视频监控系统 总被引:3,自引:0,他引:3
针对实际应用,从系统架构、应用解析、实现方法等方面介绍了将GIS技术应用于远程移动视频监控系统的解决方案。提出的视频与GIS数据集成方法是一个新的技术尝试,具有应用价值。 相似文献
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Yizhao Gao Anand Padmanabhan Junjun Yin Guofeng Cao 《International journal of geographical information science》2018,32(3):425-449
Tracking spatial and temporal trends of events (e.g. disease outbreaks and natural disasters) is important for situation awareness and timely response. Social media, with increasing popularity, provide an effective way to collect event-related data from massive populations and thus a significant opportunity to dynamically monitor events as they emerge and evolve. While existing research has demonstrated the value of social media as sensors in event detection, estimating potential time spans and influenced areas of an event from social media remains challenging. Challenges include the unstable volumes of available data, the spatial heterogeneity of event activities and social media data, and the data sparsity. This paper describes a systematic approach to detecting potential spatiotemporal patterns of events by resolving these challenges through several interrelated strategies: using kernel density estimation for smoothed social media intensity surfaces; utilizing event-unrelated social media posts to help map relative event prevalence; and normalizing event indicators based on historical fluctuation. This approach generates event indicator maps and significance maps explaining spatiotemporal variations of event prevalence to identify space-time regions with potentially abnormal event activities. The approach has been applied to detect influenza activity patterns in the conterminous US using Twitter data. A set of experiments demonstrated that our approach produces high-resolution influenza activity maps that could be explained by available ground truth data. 相似文献
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Land, Sea and Human Effort was the central theme of the 28th IGU Congress in The Hague, The Netherlands. This volume contains the key-note addresses highlighting this central theme. Three major issues regarding low-land coasts came to the fore: land-use, environmental quality and safeguarding of the land. An interesting question is whether the concentration of human activities in large urban nodes will continue, or that such nodes and hierarchies will no longer structure our world, because of the ever-increasing importance of all means of communication and transport, as indicated by Johnston. Functions may disperse to specialised environments. A similar specialisation may be encountered in e.g. the development of tourism in the coastal zone. As Gormsen has elucidated, tourism has over time extended in a sequence of spatial peripheries. Consequently, phases in development may be identified with a growing impact and participation of local tourism interwoven with international growth. The environmental quality of coastal zones is seriously under threat, due to ever-increasing population pressure and human exploitation. The major problems are pollution and the availability of good quality water. Oudshoorn explored the worlds resources of drinking water, indicating the great need for political awareness of this huge problem. Cross-sectoral planning is advocated by Oudshoorn, even if water management often trespasses international boundaries and the harmonisation of the planning strategies is mostly difficult. The environmental quality of the coastal zone is also affected by the exploitation of oil and gas resources. Odell demonstrates that the conditions for this exploitation in the North Sea are unique, especially because of the great impact of an international agreement on offshore exploitation. Planning in sea areas is becoming an issue of increasing importance as it has to cope with the many, often conflicting interests, such as shipping, fishery, mining, waste disposal in relation to environmental and ecological constraints. The safeguarding of the land against river floods and sea side storm surges under the threat of a rising sea level is another important issue in coastal low-lands. Callander reviews the present state of human influence on climatic change and the associated sea level change. As indicated by Hesselman et al. new remote sensing and associated GIS techniques have recently been developed which are a great contribution in determining the fate of the coastal zones with respect to the threats induced by natural and human activities. 相似文献
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Abnormally high-priced transactions in urban land speculation bring detrimental effects on economy, environment, and society. Governmental agencies around the world are striving hard to monitor and control land speculation by introducing various policy objectives and tools for an efficient urban development planning. One of the major challenges in controlling land speculation is to quickly identify the spatiotemporal locations of concern (hot spots) by monitoring the spatial clustering pattern changes over time and to alert the appropriate decision-making agencies for timely policy intervention. In this paper, we introduce a framework to rapidly detect the spatiotemporal hot spots of speculative land transactions in near-real-time data by exploiting the prospective monitoring procedures. We applied this method in the city of Hwasung, Republic of Korea, as an empirical illustration and found that the locations Jeongnam, Bongdam, Mado, and Dongtan were identified as hot spots with high, concentrated transaction values. The results indicate that the proposed framework is a capable tool for capturing prospective temporal indicators and pinpointing the localities of land speculation. 相似文献
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Carpenter A 《Marine pollution bulletin》2007,54(2):149-163
This paper examines the use of aerial surveillance activities conducted in the North Sea region of Europe since 1986 to assess trends in levels of oil inputs into the marine environment, both across the whole region and within the waters of the different coastal states. It makes use of data collected under the aegis of the 1969 Bonn Agreement through its Annual Reports on Aerial Surveillance and examines developments in surveillance methods and technology which have led to improvements in the detection of oil spills, even during the hours of darkness. The paper then examines country specific data for the eight North Sea contracting parties to the Agreement to assess trends in oil spills in the region. 相似文献
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Chathura Wickramasinghe Luke Wallace Karin Reinke Simon Jones 《International Journal of Digital Earth》2020,13(4):457-473
ABSTRACTThe AHI-FSA (Advanced Himawari Imager - Fire Surveillance Algorithm) is a recently developed algorithm designed to support wildfire surveillance and mapping using the geostationary Himawari-8 satellite. At present, the AHI-FSA algorithm has only been tested on a number of case study fires in Western Australia. Initial results demonstrate potential as a wildfire surveillance algorithm providing high frequency (every 10 minutes), multi-resolution fire-line detections. This paper intercompares AHI-FSA across the Northern Territory of Australia (1.4 million km2) over a ten-day period with the well-established fire products from LEO (Low Earth Orbiting) satellites: MODIS (Moderate Resolution Imaging Spectroradiometer) and VIIRS (Visible Infrared Imaging Radiometer Suite). This paper also discusses the difficulties and solutions when comparing high temporal frequency fire products with existing low temporal resolution LEO satellite products. The results indicate that the multi-resolution approach developed for AHI-FSA is successful in mapping fire activity at 500?m. When compared to the MODIS, daily AHI-FSA omission error was only 7%. High temporal frequency data also results in AHI-FSA observing fires, at times, three hours before the MODIS overpass with much-enhanced detail on fire movement. 相似文献
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Pine plantations in Australia are subject to a range of abiotic and biotic damaging agents that affect tree health and productivity. In order to optimise management decisions, plantation managers require regular intelligence relating to the status and trends in the health and condition of trees within individual compartments. Remote sensing technology offers an alternative to traditional ground-based assessment of these plantations. Automated estimation of foliar crown health, especially in degraded crowns, can be difficult due to mixed pixels when there is low or fragmented vegetation cover. In this study we apply a linear spectral unmixing approach to high spatial resolution (50 cm) multispectral imagery to quantify the fractional abundances of the key image endmembers: sunlit canopy, shadow, and soil. A number of Pinus radiata tree crown attributes were modelled using multiple linear regression and endmember fraction images. We found high levels of significance (r2 = 0.80) for the overall crown colour and colour of the crown leader (r2 = 0.79) in tree crowns affected by the fungal pathogen Sphaeropsis sapinea, which produces both needle necrosis and chlorosis. Results for stands associated with defoliation and chlorosis through infestation by the aphid Essigella californica were lower with an r2 = 0.33 for crown transparency and r2 = 0.31 for proportion of crown affected. Similar analysis of data from a nitrogen deficient site produced an outcome somewhat in between the other two damaging agents. Overall the sunlit canopy image fraction has been the most important variable used in the modelling of forest condition for all damaging agents. 相似文献