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161.
中国重要矿产资源的需求预测 总被引:18,自引:22,他引:18
以往对矿产资源的中长期需求预测,大都基于纯数学模型或情景分析对已有数据的经验外推。由于缺乏对工业化过程矿产资源消费需求基本规律的把握,预测结果几乎无一例外地存在巨大偏差。笔者在深入分析工业化经济增长与矿产资源消费需求的相关关系、基本规律和模式的基础上,探讨了工业化过程中矿产资源消费从怎样的初始值通过什么样的方式到达多高的峰值,进而提取经济增长与矿产资源消费需求的模式参数,预测了中国未来30a能源、钢、铜、铝、锌的消费需求。 相似文献
162.
新增亿元GDP用地量是衡量土地节约集约利用的重要指标,在分析烟台市新增亿元GDP用地量现状的基础上,确定烟台市新增亿元GDP用地量,并以此为基础对烟台市未来5年合理新增用地量进行预测,为促进土地节约集约利用提供参考。 相似文献
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164.
Electricity is one of the most important components in energy consumption, which is directly related to economic growth, CO2 emission and global warming. This research intends to estimate spatial distribution of electricity consumption in China, the largest developing country, and analyze the temporal and spatial change of electricity consumption during 1994–2009. The spatial modeling is based on the total electricity consumption of each province and DMSP (Defense Meteorological Satellite Program) – Operational Line-scan System (OLS) data, the latter provides the nighttime light information corresponding to electricity consumption, GDP and population. A simple method was developed to correct the saturated pixels with digital number of 63 in non-radiance-corrected DMSP-OLS data, using cities’ GDP data. The spatial electricity consumption maps were produced during 1994–2009, and they were validated by the electricity consumption records of 101 cities. Finally, the spatial–temporal changes of electricity consumption were analyzed. The results of this research can help to understand the regional discrepancy, especially rural and urban areas of China, of electricity consumption and economic development. 相似文献
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167.
我国经济增长的自组织模型研究 总被引:2,自引:0,他引:2
经济系统的复杂性决定了经济变动及影响因素解释的困难性.应用自组织数据挖掘方法,建立一个解释我国GDP增长的自组织模型,同时与用主成分分析方法建立的GDP增长模型进行比较,分析影响我国经济增长的主要因素,并在此基础上提出相应的对策思路. 相似文献
168.
《Marine Policy》2014
There are tradeoffs in managing fisheries, and ideally such tradeoffs should be known when setting fisheries policies. An aspect of this, which is rarely considered, is the spin-off effect of different fisheries: the economic and social benefits that fisheries generate through processing through distribution and on to the end consumer. This study evaluated the benefits generated in the Peruvian marine fisheries sector through a comprehensive value chain analysis, based on a newly-developed combined ecosystem-economic modeling approach, which was integrated in the widely-used Ecopath with Ecosim approach and software. The value chain was parameterized by extensive data collection through 35 enterprise types covering the marine fisheries sector in Peru, including the world's biggest single-species fishery for anchoveta. While anchoveta is what is known about Peruvian fisheries, the study finds that anchoveta accounts for only 31% of the sector contribution to GDP and for only 23% of the employment. Thus, while anchoveta indeed is the fundamental fish species in the Peruvian ecosystem, there are other fisheries to be considered for management. The study indicates that the economic multipliers for Peruvian fisheries were 2.9 on average over the industry, and that these varied surprisingly little between fleets and between seafood categories indicating that the multipliers can be used beyond Peru to generalize the spin-off effect of the value chain. Employment multipliers vary much more across types of fisheries, but also around an average of 2.9; here it was clear that longer value chains result in more employment. 相似文献
169.
新疆天山北坡干旱区GDP时空模拟 总被引:6,自引:1,他引:5
针对资源环境研究领域对空间型社会经济数据的需求,本文以新疆天山北坡为试验区,在分析区域经济发展特征的基础上,根据分县控制、分产业建模的思路,建立基于土地利用的1 km栅格GDP空间化模型对统计型经济数据进行空间分布仿真模拟。对第一产业产值采用面积权重的方法进行拟合;对第二产业建立基于道路的反距离加权模型;第三产业则以城镇规模为基础,通过引入城市边缘距离概念建立多中心的距离衰减加幂指数模型。结果表明,天山北坡GDP空间分布模拟在分产业和分县水平上具有较高精度,模拟值与真实值间的相对误差均在1%以内。从研究区GDP的空间分布来看,高值区主要集中在米泉至沙湾一线,以乌鲁木齐市、石河子市以及克拉玛依市为核心向周围地区辐射;城市内部GDP密度由城市中心向外围递减,建成区GDP密度明显高于城郊及农村地区。1995、2000和2007年三期GDP模拟结果的对比较真实地反映了区域经济发展的历程,对准确把握区域经济动态具有一定的实用价值。 相似文献
170.
Control of atmospheric CO<Subscript>2</Subscript> concentrations by 2050: A calculation on the emission rights of different countries 总被引:1,自引:0,他引:1
This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system ... 相似文献