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Comparison between two time points of the same categorical variable for the same study extent can reveal changes among categories over time, such as transitions among land categories. If many categories exist, then analysis can be difficult to interpret. Category aggregation is the procedure that combines two or more categories to create a single broader category. Aggregation can simplify interpretation, and can also influence the sizes and types of changes. Some classifications have an a priori hierarchy to facilitate aggregation, but an a priori aggregation might make researchers blind to important category dynamics. We created an algorithm to aggregate categories in a sequence of steps based on the categories’ behaviors in terms of gross losses and gross gains. The behavior-based algorithm aggregates net gaining categories with net gaining categories and aggregates net losing categories with net losing categories, but never aggregates a net gaining category with a net losing category. The behavior-based algorithm at each step in the sequence maintains net change and maximizes swap change. We present a case study where data from 2001 and 2006 for 64 land categories indicate change on 17% of the study extent. The behavior-based algorithm produces a set of 10 categories that maintains nearly the original amount of change. In contrast, an a priori aggregation produces 10 categories while reducing the change to 9%. We offer a free computer program to perform the behavior-based aggregation. 相似文献
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月球的构造演化:嫦娥月图解释的理论基础 总被引:7,自引:0,他引:7
基于月球研究资料的整理、综合及嫦娥1月图影像的实例解读和解释,本文介绍并总结了月球的构造及演化研究的若干概念、研究思路和新的观点。通过纲要性勾画,描绘月球不同类型和阶段构造演化的基本轮廓,重点论述了四个方面的问题:对月面建造历史和月球演化的历史进行了修正,将月球演化按照其特点三分为冥、古、新月宙/界,并提出建立南海纪/系的主张;以东海Hevelius抛射建造(/东海群)分析为例,主张建立构造一建造综合分析思路;从抛射建造与月面相互作用的角度,提出并阐述了掘积系统的概念、掘积系统内外带之间划分的新标志即蚀积盂及其所组成的捩侵蚀带(TSZ);在月球表面形貌构造区划分析的基础上,通过对月盆、月海的时空分布规律的分析、综合,提出月球晚期大轰击(LHB)所造成的月盆开掘期间,具有“轰击漂移”现象,并推测月球LHB过程中出现准对跖翻转;通过对古老月陆区所保存的线性构造解读和构造形迹的组合关系分析,尝试性地提出在冥月宙月球岩浆洋(LMO)演化晚期可能存在单板模式的月全球构造。月球构造演化从初始阶段的LMO所驱动的内动力体制转向冲击造成的外动力体制。 相似文献
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The variations of sea ice are different in different regions in Antarctica, thus have different impacts on local atmospheric circulation and global climatic system. The relationships between the sea ice in Ross Sea and Weddell Sea regions and the synoptic climate in summer of China are investigated in this paper via diagnostic analysis methods by using global sea ice concentration gridded data covering Jan. 1968 through Dec. 2002 obtained from Hadley Center, combined with Geopotential Height on 500hPa and 100hPa over North Hemisphere and monthly precipitation and air temperatures data covering the corresponding period over 160 meteorological stations in China obtained from CMA ( China Meteorological Administration). Results disclose that both these two regions are of indicative meanings to the climate in summer of China. The Ross Sea Region is the key sea ice region to the precipitation in Northeast China in summer. More sea ice in this region in September will result in less precipitation in Northeast China in the following June. Weddell Sea Region is the key sea ice region to the air temperature in Northeast China in summer. More sea ice in this region in September will contribute to lower air temperature in Northeast China in the following June. 相似文献
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Beverley Darkin 《Climate Policy》2013,13(3):257-274
Abstract New Labour came to power in 1997 pledging to put environment concerns at the heart of policy-making. Shortly after being elected, the Labour Government signed the Kyoto Protocol and adopted a voluntary domestic target of a 20% cut in carbon dioxide emissions by 2010. This article looks at the development of UK climate policy since 1997 and the political drivers that have led to development of the climate policy mix. It assesses the Climate Change Programme adopted in 2000 and its delivery, and it also looks at the 5-year Climate Change Programme Review published in March 2006. It conducts a quantitative assessment of the UK's performance by looking at emissions data, and it also provides a qualitative analysis, by looking at the UK policies and measures within their political and institutional context. The article concludes that Labour has been actively promoting climate policy since coming to power and has played a strong leadership role internationally. The UK is on track to meet and surpass its Kyoto target, meeting its international commitments. Between 24.1 and 29.1 million tonnes of carbon savings per year are expected by 2010. Policies and measures in the industrial sector are delivering real emissions reductions, in addition to the reductions made through fuel switching. The Government has found it more difficult to make some of the tough choices necessary to deliver emissions reductions in the transport and the household sectors. The article seeks to explain why the Labour Government has found it uncomfortable, politically, to implement stronger measures in these parts of the economy. The article highlights the changing dynamics within UK politics and concludes that there are two possible avenues for taking more stringent measures in the future. The first involves the development of a cross-party consensus on climate change. The second is to change the way that climate change is framed, so that it is no longer seen as an ‘environment’ issue but one with which voters and decision-makers can immediately connect. Only then will it be possible to implement the necessary policies and measures across the whole economy. 相似文献
218.
《Climate Policy》2013,13(4):293-301
Abstract This article summarises the results of an evaluation of the Climate Change Initiative launched by President Bush in February 2002. The policy target to reduce the greenhouse gas intensity of the US economy by 18% between 2002 and 2012 can be considered modest at best. The Initiative is likely to result in a 32% increase in US greenhouse gas emissions in 2012 compared to the 1990 levels. The effort also falls considerably short of efforts of the EU, Japan and Canada under the Kyoto Protocol. The Bush Initiative advocates using intensity targets in the international climate change regime, but overlooks fundamental problems associated with this approach. All the same, the Bush Initiative is of political significance as it recognises the importance of the climate change problem and may improve the longer-term prospects for US participation in a global climate regime. 相似文献
219.
《Climate Policy》2013,13(2-3):231-239
Abstract Articles 4.8 and 4.9 of the United Nations Framework Convention on Climate Change (UNFCCC) and Article 3.14 of its Kyoto Protocol require parties to take measures to minimise the adverse effects of climate change on developing and least developed countries (LDCs). The Alliance of Small Island States (AOSIS) argue that this should mean assistance for capacity building to help them adapt to a changing climate. Articles 4.8 and 3.14 also require parties to take measures to minimise the impacts of emission reduction measures on energy exporting countries. The Organisation of Petroleum Exporting Countries (OPEC) countries argue that this should mean assistance to compensate for lost oil revenues. This paper explores the dimensions of the adverse effects/impacts issue. It explains how, in arguing that progress on Articles 4.8, 4.9 and 3.14 be equal to progress on the issue of assistance to compensate for lost oil revenues, OPEC countries obstruct progress on assistance to developing and LDCs for adaptation to climate change. This suggests that tacit G77/China support for OPEC's position may ultimately not be in their best interests. The paper discusses the outlook for the adverse effects/impacts of response measures issue. 相似文献
220.
Drawing on the adaptation, justice, and resettlement literatures, this study explores the prospects for procedural (who is involved, how they are selected) and distributive justice (how the outcomes are experienced by different groups) in a resettlement project in the coastal city of Iloilo in the Philippines. This project, which sought to reduce flood risks, required the resettlement of 3500 families. The city was lauded locally and internationally and the government intends to replicate it across the country. This study uses a mixed method approach, including 200 household surveys and interviews with government officials, NGO staff, and community members. It finds that while some households experience notable improvements in their housing quality, incomes and climate resilience, the resettlement process exacerbated intra-community inequality and exclusion. It also finds that the distribution of these benefits was a function of political power and pre-existing wealth discrepancies rather than of need. To avoid these mistakes in the future, governments and resettlement planners must take account of how inequality and asymmetries in power shape resettlement outcomes. To do this, questions of procedural, distributive and contextual justice must be brought to the fore. 相似文献