首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   286篇
  免费   16篇
  国内免费   6篇
测绘学   65篇
大气科学   15篇
地球物理   28篇
地质学   52篇
海洋学   11篇
天文学   1篇
综合类   23篇
自然地理   113篇
  2024年   1篇
  2023年   1篇
  2022年   9篇
  2021年   6篇
  2020年   7篇
  2019年   13篇
  2018年   6篇
  2017年   17篇
  2016年   6篇
  2015年   16篇
  2014年   14篇
  2013年   28篇
  2012年   17篇
  2011年   9篇
  2010年   11篇
  2009年   11篇
  2008年   20篇
  2007年   20篇
  2006年   16篇
  2005年   11篇
  2004年   9篇
  2003年   21篇
  2002年   7篇
  2001年   4篇
  2000年   6篇
  1999年   2篇
  1998年   2篇
  1996年   1篇
  1995年   1篇
  1994年   2篇
  1993年   5篇
  1988年   2篇
  1987年   2篇
  1985年   1篇
  1983年   1篇
  1982年   3篇
排序方式: 共有308条查询结果,搜索用时 0 毫秒
141.
福建省政务信息资源标准规范改造与集成   总被引:1,自引:0,他引:1  
对电子政务的标准化和网络化推行,政务信息数据标准化改造和共享集成是基础。本文分析了福建省政务信息资源的现状,提出了省级政务信息资源标准化、规范化改造的信息共享、分类体系、交换接口和信息服务模式。开发了福建省政务信息共享平台,充分应用XMLWebServices技术,将政务数据库分别按空间数据库、关系数据库、文件数据和多媒体数据4种类型,将分布在各单位、各行业的异构数据库集成到共享平台,并采用面向信息服务的集成架构,将多个分布式异构数据库进行实时的XML格式化,依据不同的共享级别按4种服务方式集成到各个应用系统中,实现数据库与应用系统的整合,提高政务信息资源的共享利用与服务水平。  相似文献   
142.
The latest Cretaceous continental vertebrate faunas of the wider Transylvanian area figured prominently in discussions concerning the Cretaceous–Paleogene Boundary (K-Pg) events when they were first described by Nopcsa between 1897 and 1929, because they were assumed to be late Maastrichtian in age. Subsequently their age was reconsidered as early Maastrichtian, and were thus regarded of lesser importance in understanding the K-Pg boundary events in Europe and worldwide. Moreover, Transylvanian continental vertebrate assemblages (the so-called ‘Haţeg Island’ faunas) were often lumped together as a temporally restricted assemblage with a homogenous taxonomic composition. Recent fossil discoveries and more precise dating techniques have considerably expanded knowledge of the Transylvanian vertebrate assemblages, their ages, and their evolution. A synthesis of the available stratigraphic data allows development of the first comprehensive chronostratigraphic framework of the latest Cretaceous Transylvanian vertebrates. According to these new data, expansion of continental habitats and emergence of their vertebrate faunas started locally during the latter part of the late Campanian, and these faunas continued up to the second half of the Maastrichtian. During this time, long-term faunal stasis appears to have characterized the Transylvanian vertebrate assemblages, which is different from the striking turnovers recorded in western Europe during the same time interval. This suggests that there was no single ‘Europe-wide’ pattern of latest Cretaceous continental vertebrate evolution. Together, the available data shows that dinosaurs and other vertebrates were relatively abundant and diverse until at least ca. 1 million years before the K-Pg boundary, and is therefore consistent with the hypothesis of a sudden extinction, although this must be tested with future discoveries and better age constraints and correlations.  相似文献   
143.
In 2009, New Zealand's new National-led government abandoned the Carbon Neutral Public Service (CNPS) programme, a Labour-led government initiative intended to help Government achieve carbon neutrality within its core agencies. This short analysis article provides an overview and brief assessment of the CNPS initiative by drawing on the relevant scholarly literature and public documents relating to New Zealand's climate change agenda. It is argued that although the CNPS programme faced a range of challenges it was successful in some respects. Although the Labour-led government was keen to act on climate change mitigation, New Zealand no longer intends to take a lead on carbon neutrality under the National-led government.  相似文献   
144.
《Climate Policy》2013,13(1):813-828
A novel approach is described for limiting transport emissions through a cap-and-trade emissions trading scheme, whereby local governments would be the participants of emissions trading. It is proposed that emissions trading for passenger road transport has the effect of channelling the carbon costs away from fuel prices to land use costs. A ‘municipal emissions trading scheme’ could achieve this—local governments would have to cover vehicle traffic emissions generated by homes, businesses and industry on their territory. Municipalities are able to participate in an emissions trading scheme because they have planning control over development on their territory, and could control the amount of future vehicular traffic. Through planning, municipalities have access to a wide range of strategies to minimize transport emissions. Municipal emissions can be calculated as a share of total national road transport emissions with the help of a gravity model of traffic attraction. A municipal emissions trading system would result in capping and controlling passenger road transport emissions, not through raising fuel prices or importing credits, but by enforcing prudent and climate-efficient urban planning practices.  相似文献   
145.
GIS的发展一直伴随着在电子政务中的不断应用,基于GIS技术的国土资源电子政务信息系统是当前国土资源信息化建设的重要技术手段之一。结合湖南省长沙县国土资源电子政务信息系统开发的实际,全面阐述了以ArcGIS为基础开发平台的一体化国土资源电子政务信息系统的设计思想、目标、整体结构以及功能的实现,并对系统实现的关键技术问题...  相似文献   
146.
中国地方政府财政赤字率的时空演变——地理监视的应用   总被引:1,自引:1,他引:1  
纪小美  王超  赵晓迪 《地理科学》2019,39(3):424-432
运用重心模型、时空跃迁和地理监视揭示了中国地市财政赤字率的时空演变规律与空间相互作用。赤字率重心西移,地域不均衡。赤字率分布具有路径依赖和空间溢出效应。经济越落后赤字风险越高,赤字冷点区集中于沿海且消退;热点区东扩且风险上升。赤字累积风险顺地势阶梯递减。 广大中东部地市为非预警区,继续积极财政政策,但支出需偏向社会福利,依靠内需拉动经济增长;预警区多为中西部工业城市,应增强内生动力以实现财政与经济长期协调发展;调控区集中于青藏高原及边缘,中央应加大扶持民生,减轻地方压力。  相似文献   
147.
BOOK REVIEWS     
Book Reviewed in this article: Portable Utopia: Glasgow and the United States 1820–1920. Bernard Aspinwall. Studies in Russian Historical Geography. James H. Bater and R. A. French, eds. Water and Sanitation: Economic and Sociological Perspectives. Peter G. Bourne, ed. Green Politics. Fritjof Capra and Charlene Spretnak. The Southern Cone: Realities of the Authoritarian State. César N. Caviedes. Women in Third World Development. Sue Ellen Charlton. Land Management: New Directions. David Chiddick and Alan Millington, eds. Geography and Ethnic Pluralism. Colin Clarke, David Ley, Ceri Peach, eds. Geomorphological Hazards in Los Angeles. R. U. Cooke. Regional Impacts of United States-Mexico Economic Relations. Alfonso Corona and Lay James Gibson. eds. Patterns of Jobs and Geographic Mobility. Torvald Gerger. Cities and Sickness: Health Care in Urban America. Ann Lennarson Greer and Scott Greer, eds. Neighborhoods: Their Place in Urban Life. Howard W. Hallman. Development and the Rural-Urban Divide. John Harriss and Mick Moore, eds. Patterns of Undocumented Migration: Mexico and the United States. Richard C. Jones, ed. Central Place Theory. Leslie J. King. The Geography of Western Europe: A Socio-economic Survey. Paul L. Knox. Regions and Resources: Strategies for Development. David T. Krisge, Daniel A. Seiver, Oliver S. Goldsmith and Michael J. Scott. Geography of Crowding and Human Response. A Study of Ahmedabad City. K. M. Kulkarni. Haciendo Pueblo. The Development of a Guadalajaran Suburb. Kathleen Logan. The Imperial Lion: Human Dimensions of Wildlife Management in Central Africa. Stewart A. Marks. Water in the Hispanic Southwest: A Social and Legal History, 1550–1850. Michael C. Meyer. Imlil: A Moroccan Mountain Community in Change. James A. Miller. Tourism in Canada: Selected Issues and Options. Peter E. Murphy, ed. David Harvey's Geography. John L. Paterson. Raster Scanning, Processing and Plotting of Cartographic Documents. Donna J. Peuquet and A. Raymond Boyle. The USSR and the Muslim World: Issues in Domestic and Foreign Policy. Yaacov Ro'i, ed. Environmental Perception and Behavior: An Inventory and Prospect. Thomas F. Saarinen, David Seamon, and James L. Sell. Incised channels, Morphology, Dynamics, and Control. Stanley A. Schumm, Michael D. Harvey, and Chester C. Watson. The Gap Between Rich and Poor: Contending Perspectives on the Political Economy of Development. Mitchell A. Seligson, ed. Twentieth-Century Richmond. Planning, Politics and Race. Christopher Silver. Land Conservation and Development: Examples of Land-Use Planning Projects and Programs. F. R. Steiner and H. N. van Lier, eds. Biogeography: Recent Advances and Future Directions. J. A. Taylor, ed. Late Quaternary Environments of the Soviet Union. A. A. Velichko, ed. H. E. Wright, Jr. and C. W. Barnosky, eds.  相似文献   
148.
Abstract

In the past 10 years, geographic information systems (GIS) have been widely used in urban and regional planning in the developed countries in Australia, North America and Europe. However, the use of GIS in urban and regional planning in the developing countries is limited and still at an early stage of development. This paper examines the current use of GIS in urban and regional planning in the developing countries in Asia. The major hindrances in the use of GIS in the developing countries is related not so much to the technology of GIS but more to data availability, leadership, organization structure and planning practice. For GIS to be more useful to urban and regional planning in the developing countries the development of a sustainable strategy in developing GIS and staff training is needed. International assistance agencies and GIS software companies can play an active role in making GIS available and usable to the planners in the developing countries.  相似文献   
149.
围绕地质资料管理和公共服务需求,以提高地质资料管理效率和服务能力为目标,分析了地质资料信息管理服务现状和存在的问题,提出"用户为本、资源整合、业务协同、共享服务"的总体建设思路。地质资料信息管理服务系统建设以业务需求驱动应用集成,借鉴"互联网+政务服务"应用模式,以地质资料政务信息管理和公共服务为核心构建系统总体架构,实现全国地质资料管理和服务信息的"一站协同、一网通查、一码通管",推进全国地质资料管理和服务信息的共享利用,形成"全国统一、动态更新、多级联动、权威发布"的地质资料管理和服务体系,为地质资料汇交和社会公众提供更好的服务。  相似文献   
150.
政府决策需要地理信息支持,地理信息能有效辅助政府决策,这种需求和应用的有效契合,促进了地理信息在政府决策的广泛和深入应用.在剖析政府决策应用地理信息现状的基础上,结合政府决策的需求前景和地理信息技术前景,提出地理信息更好服务政府决策的对策与建议.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号