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广东省碳减排总量目标的地区分解及其盈亏格局 总被引:1,自引:0,他引:1
合理界定初始排放权并进行排放权交易是实现减排目标和减排资源最优配置的关键。对低碳试点省广东进行减排目标地区分解,既能明确减排责任,又能使碳交易变得更加明确而具有可操作性。设定广东碳减排目标的假设情景,以碳排放核算方法和最优经济增长模型为基础,引入兼顾人均平等和历史责任的“碳预算”思路,对广东省减排目标进行地区分解,计算各市排放权配额并测算未来时期排放权的盈亏格局,初步模拟广东省各市之间“碳交易”基础。结果表明:1)1985―2020年全省累积碳排放配额区间为524 659.185 5~542 518.565 2万t,人均碳排放配额区间为57.065 5~59.008 0 t/人。人均碳排放配额、人口数量和实际碳排放量是影响各市排放权配额的重要因素。2)预计到2020年7个城市将出现“碳预算”赤字,主要分布于珠三角;14个城市拥有“碳预算”盈余,集中分布在粤北山区和东西两翼。 相似文献
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以认知神经科学的研究成果为依据,对视网膜会强烈响应大反差视觉刺激的现象和初级视觉皮层上视觉信息的生成机制进行了模拟,提出了一种基于视觉反差的显著图生成与目标检测方法。本方法可以在不考虑目标的形状、边缘或其他形式先验知识的情况下检测出场景中具有显著反差的目标。在对地场景中车辆目标的检测实验里,将其与另外两种典型的显著图生成方法进行了对比,结果显示,这种基于视觉反差的目标检测方法能够较好地将注意力集中在场景中具有较大反差的目标之上,且具有高效性和鲁棒性。 相似文献
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The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR. 相似文献
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以河北省昌黎地震台为例,使用该台地磁Z分量的分钟值数据,分别对比了正常时段、磁暴发生时段、 低点位移时段的主要频率谱值变化特征. 通过多频点功率谱对数拟合,发现在数据长度相等的情况下,相对于正常时段而言磁暴时段各频率的能量明显增强,特别是高频端尤其明显; 而当大范围低点位移发生时,高频端的能量基本与正常时段持平,但4个小时以上的周期功率谱大部分要低于正常段. 通过对多日低点位移时段的FFT累加与正常时段对比后发现,低点位移发生时,8.5小时和13.7小时周期的频谱值增加. 通过与DE-METER卫星观测的电子密度数据空间图象进行对比,发现地磁低点位移的发生与空间Ne的增加有很好的对应性. 最后对这些变化特征及低点位移可能产生的机制进行了探讨. 相似文献
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The “Grain for Green Project” initiated by the governments since 1999 were the dominant contributors to the vegetation restoration in the agro-pastoral transitional zone of northern China. Climate change and human activities are responsible for the improvement and degradation to a certain degree. In order to monitor the vegetation variations and clarify the causes of rehabilitation in the Shaanxi-Gansu-Ningxia Region, this paper, based on the MODIS-NDVI and climate data during the period of 2000-2009, analyzes the main characteristics, spatial-temporal distribution and reasons of vegetation restoration, using methods of linear regression, the Hurst Exponent, standard deviation and other methods. Results are shown as follows. (1) From 2000 to 2009, the NDVI of the study area was improved progressively, with a linear tendency being 0.032/10a, faster than the growth of the Three-North Shelter Forest Program (0.007/10a) from 1982 to 2006. (2) The vegetation restoration is characterized by two fast-growing periods, with an “S-shaped” increasing curve. (3) The largest proportion of the contribution to vegetation restoration was observed in the slightly improved area, followed by the moderate and the significantly improved area; the degraded area is distributed sporadically over southern part of Ningxia Hui Autonomous Region as well as eastern Dingbian of Shaanxi province, Huanxian and Zhengyuan of Gansu province. (4) Climate change and human activities are two driving forces in vegetation restoration; moreover anthropogenic factors such as “Grain for Green Project” were the main causes leading to an increasing trend of NDVI on local scale. However, its influencing mechanism remains to be further investigated. (5) The Hurst Exponent of NDVI time series shows that the vegetation restoration was sustainable. It is expected that improvement in vegetation cover will expand to the most parts of the region. 相似文献
69.
历史时期渭河中下游平原水旱灾害 总被引:3,自引:0,他引:3
1IntroductionFor long historical development course, we know that the changes of natural environment and resources have interactive effect with the construction, development and decline of the cities. Internationally, there were some relevant researches, … 相似文献
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