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121.
Andoni Arenas-Martija Victor Salinas-Silva Leonor Margalef-García Maria Otero-Auristondo 《The Journal of geography》2017,116(2):57-66
This research aims to evaluate the geographical knowledge of nine teachers in the region of Valparaiso, Chile. An interpretive case study was conducted with data collected through classroom observations, interviews, and questionnaires, and these data were then analyzed through triangulation. The findings showed that these teachers, who are the most qualified within the region's context, consider geography to be marginal knowledge in the school curriculum, although they also consider it relevant to the education of their pupils. Both elements provided evidence of the fragility of their geographical knowledge, which fell within a spectrum that combines expert knowledge and lay knowledge. 相似文献
122.
H.-W. Ma 《Stochastic Environmental Research and Risk Assessment (SERRA)》2002,16(6):464-478
There exist many sites with contaminated groundwater because of inappropriate handling or disposal of hazardous materials
or wastes. Health risk assessment is an important tool to evaluate the potential environmental and health impacts of these
contaminated sites. It is also becoming an important basis for determining whether risk reduction is needed and what actions
should be initiated. However, in research related to groundwater risk assessment and management, consideration of multimedia
risk assessment and the separation of the uncertainty due to lack of knowledge and the variability due to natural heterogeneity
are rare. This study presents a multimedia risk assessment framework with the integration of multimedia transfer and multi-pathway
exposure of groundwater contaminants, and investigates whether multimedia risk assessment and the separation of uncertainty
and variability can provide a better basis for risk management decisions. The results of the case study show that a decision
based on multimedia risk assessment may differ from one based on risk resulting from groundwater only. In particular, the
transfer from groundwater to air imposes a health threat to some degree. By using a methodology that combines Monte Carlo
simulation, a rank correlation coefficient, and an explicit decision criterion to identify information important to the decision,
the results obtained when uncertainty and variability are separate differ from the ones without such separation. In particular,
when higher percentiles of uncertainty and variability distributions are considered, the method separating uncertainty and
variability identifies TCE concentration as the single most important input parameter, while the method that does not distinguish
the two identifies four input parameters as the important information that would influence a decision on risk reduction. 相似文献
123.
白垩系是西昆仑山前地区最重要的储层,受区域构造演化控制,其岩性与分布在纵、横向上均发生变化。下白垩统为冲积扇辫状河相沉积的红色砾岩、砂岩夹泥岩;上白垩统英吉沙群在研究区西部为一套海相碳酸盐岩地层。白垩系在喀什凹陷最厚,往西、往东、往北均逐渐变薄,并发生相变与尖灭,控制储层发育。本文在研究区域首次通过地震相研究,根据白垩系反射特征精细追踪对比其层位,确定尖灭位置,进而确定白垩系分布范围。研究认为,地震相能在区域上宏观地反映白垩系的沉积特征与分布范围,进而指导油气勘探,具有很重要的现实意义。 相似文献
124.
地块—海槽边缘带成油成气新概念 总被引:1,自引:0,他引:1
对准噶尔,塔里木等盆地沉积环境的研究表明,古生代时,中国西北区海相沉积,沉积盆地的基底是一些离散的古老结晶地块,其上海水侵浸,地块之间为大洋或窄大洋的海槽,地块之间的海槽或地块与海槽过渡的边缘带盆地是油气形成的有利地带。 相似文献
125.
126.
The seismic assessment of the local failure modes in existing masonry buildings is currently based on the identification of the so‐called local mechanisms, often associated with the out‐of‐plane wall behavior, whose stability is evaluated by static force‐based approaches and, more recently, by some displacement‐based proposals. Local mechanisms consist of kinematic chains of masonry portions, often regarded as rigid bodies, with geometric nonlinearity and concentrated nonlinearity in predefined contact regions (unilateral no‐tension behavior, possible sliding with friction). In this work, the dynamic behavior of local mechanisms is simulated through multi‐body dynamics, to obtain the nonlinear response with efficient time history analyses that directly take into account the characteristics of the ground motion. The amplification/filtering effects of the structure are considered within the input motion. The proposed approach is validated with experimental results of two full‐scale shaking‐table tests on stone masonry buildings: a sacco‐stone masonry façade tested at Laboratório Nacional de Engenharia Civil and a two‐storey double‐leaf masonry building tested at European Centre for Training and Research in Earthquake Engineering (EUCENTRE). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
127.
128.
为监测公网盲区地质灾害,提出采用无线信号将前端传感器采集的数据传输到主站,然后使用公网信号再将数据传输到后端指挥中心.对珠峰保护区泥石流沟公网盲区泥石流的监测实验表明,该方法是可行的. 相似文献
129.
130.
田泽海 《测绘与空间地理信息》2014,(3):164-166,169
通过对利用网络RTK控制点进行放线测量的现有作业模式的总结,提出了一些质量控制技术的改进。通过测量手簿的集成和基于PDA的放线测量程序的二次开发,实现了由PDA放线测量程序对GZCORS-RTK数据进行质量控制。与以前的作业模式的比较,质量得到有效控制,效率得到提高。 相似文献