全文获取类型
收费全文 | 299篇 |
免费 | 18篇 |
国内免费 | 15篇 |
专业分类
测绘学 | 75篇 |
大气科学 | 20篇 |
地球物理 | 39篇 |
地质学 | 82篇 |
海洋学 | 9篇 |
天文学 | 1篇 |
综合类 | 45篇 |
自然地理 | 61篇 |
出版年
2022年 | 2篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 9篇 |
2014年 | 12篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 18篇 |
2010年 | 10篇 |
2009年 | 18篇 |
2008年 | 12篇 |
2007年 | 18篇 |
2006年 | 17篇 |
2005年 | 24篇 |
2004年 | 12篇 |
2003年 | 9篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 12篇 |
1999年 | 16篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有332条查询结果,搜索用时 56 毫秒
101.
102.
土木大类测量实习基地的建设探讨 总被引:1,自引:0,他引:1
索俊锋 《测绘与空间地理信息》2011,(6):7-9,17
从土木工程专业培养目标和测绘学科的发展出发,考虑民族院校特点和所在校区的具体情况,探讨了实习基地建立原则,建立校内普通测量、野外综合测量实习基地的方法、实施步骤和功能,旨在加强实践教学,培养学生的动手操作能力,为进一步深化非测绘工程专业测量学教学实习改革创造了良好的条件。 相似文献
103.
对加强地震政府网站地震突发事件信息保障工作的思考 总被引:1,自引:0,他引:1
地震政府网站是地震行业面向社会宣传防震减灾工作、服务公众的重要窗口.汶川、玉树地震后,地震工作越来越受到社会的关注,地震政府网站已成为社会公众和主流媒体、网站获取地震信息的重要平台,在抗震救灾中发挥着越来越重要的作用.本文通过地震政府网站在汶川、玉树等地震突发事件中信息保障工作的实践,从网站应急制度建设、编制网站应急预... 相似文献
104.
105.
106.
政府网络监管与个人隐私保护 总被引:1,自引:0,他引:1
石雁 《成都信息工程学院学报》2006,21(1):101-104
网络时代政府监管与个人隐私保护的冲突问题比以往更加突出,我国有关法律法规涉及到网络空间个人隐私权的法律保护问题,但缺少操作细则,立法应当对政府的网络监管权作出制约.在网络上实现巨大公共利益的同时,实现对个人隐私的保护. 相似文献
107.
盛楠 《成都信息工程学院学报》2006,21(4):604-608
行政生态平衡包括行政个体、行政团体、行政整体的平衡以及行政系统与社会环境诸要素间的平衡。如果行政系统的能量变换和物质循环处于平衡动态,系统的活动就能正常开展;否则系统活动将失调,平衡难以实现。 相似文献
108.
以乌鲁木齐市矿政管理业务需求与特点为基础,对矿政管理业务系统进行了分析与设计,并基于Super-Map iServer平台进行构建。系统实现了矿权登记、储量管理、规费管理、地质环境、矿山年检、数据交换等业务需求。该矿政管理系统实现了一体化、集成化的业务管理,提升了乌鲁木齐市国土资源矿政业务的管理水平,对基层矿政管理系统的建设具有一定的借鉴意义。 相似文献
109.
Tobias Böhmelt 《Climate Policy》2013,13(6):698-717
Does civil society lobbying affect states’ policies on climate change? Does it facilitate or hamper cooperation towards ‘greener’ policies? Environmental non-governmental organizations (ENGOs) and business lobbying groups alike are increasingly seeking to access states’ negotiation delegations at the United Nations Framework Convention on Climate Change (UNFCCC) in order to affect or even change official delegates’ policies. Previous studies have failed to control for the fact that the set of states that have granted civil society access to their delegations is unlikely to be a random sample. Moreover, the fact that a delegation's policy outputs may converge with the preferences of a civil society group cannot be taken as evidence that it was caused by civil society lobbying. A matching approach that addresses both problems is proposed, which corrects for the non-random assignment of civil society organizations to state delegations and forms quasi-experimental contrasts by sampling a set of ‘most similar’ cases that only differ in their treatment; i.e. civil society lobbying. This approach facilitates a causal interpretation of lobbying efforts. The results indicate that only business groups are likely to exert a causal influence on states’ climate delegations. However, contrary to expectations, these groups appear to have enhanced states’ efforts towards environmentally friendly policies.Policy relevanceWhat impact can non-governmental actors have in influencing states’ policies at the climate change negotiations? This question is addressed empirically using a matching approach, which corrects potential challenges in the research on interest group influence. It is shown that business groups are likely to influence states’ policies at the UNFCCC – unlike green interest groups or civil society in general. In light of these findings, three policy implications are derived that might be of importance for states and non-governmental decision makers alike. Most importantly, ENGOs should refocus their efforts for exerting their influence. ENGOs could make their lobbying more effective by first identifying the states that may be more receptive to their preferences and positions. 相似文献
110.
ABSTRACTThe administration of U.S. President Donald Trump has promised to stop the ongoing spiralling down of the U.S. coal industry. We discuss the origins of the decline and assess the effects of policy interventions by the Trump administration. We find that, with fierce competition from natural gas and renewables, a further decrease of coal consumption must be expected by the old and inefficient U.S. coal-fired electricity generation fleet. By contrast, we consider the overly optimistic (for coal producers) view of the U.S. Energy Information Agency, and test whether the tide for the U.S. coal industry could turn as a result of three potential support measures: (i) revoking the Clean Power Plan (CPP); (ii) facilitating access to the booming Asian market; and (iii) enhanced support for Carbon Capture, Transport and Storage (CCTS) technology. We investigate the short-term and long-term effects on U.S. coal production using a comprehensive partial equilibrium model of the world steam coal market, COALMOD-World (Holz, Haftendorn, Mendelevitch, & von Hirschhausen, 2016). We find that revoking the CPP could stop the downward trend of steam coal consumption in the U.S., but even allowing for additional exports, will not lead to a return of U.S. coal production to the levels of the 2000s, that is, over 900?Mt per year. When global steam coal use is aligned with the 2°C climate target, U.S. steam coal production drops to around 100?Mt per year by 2030 and below 50?Mt by 2050, even if CCTS is available and exports via the U.S. West Coast is possible.Key policy insights
Declining U.S. coal use is primarily caused by competition from natural gas and renewables not by environmental regulation of the coal sector.
Without substantial policy support, U.S. coal-fired generation capacity will continue to decline rapidly.
Revoking the Clean Power Plan will lead to about one eighth higher U.S. coal production in the next years.
Carbon Capture, Transport and Storage does not prevent the rapid decline of coal use required under stringent climate policy.
Even in the most extreme pro-coal scenarios with additional export possibilities, U.S. coal production will not return to its pre-2010 levels.