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991.
经历多期构造运动后叠合形成的塔河西南部,用常规速度分析及成图方法都无法制作高精度的构造图,不能满足生产的需要。这里利用塔河西南部钻遇S-D的50口钻、测井资料和3D地震资料,提出了以标准层为基础的井控外推法来拟合速度并最终作构造图的方法。该方法简单实用、成本低,与实际钻探圈闭相对误差小于1.5%,能满足成图精度要求。同时,在研究过程中还发现了多个圈闭,这必将对该区油气资源的重新评价及进一步勘探有重要意义。 相似文献
992.
Danilo R. Velis 《Mathematical Geology》2007,39(4):409-417
Stationary segments in well log sequences can be automatically detected by searching for change points in the data. These
change points, which correspond to abrupt changes in the statistical nature of the underlying process, can be identified by
analysing the probability density functions of two adjacent sub-samples as they move along the data sequence. A statistical
test is used to set a significance level of the probability that the two distributions are the same, thus providing a means
to decide how many segments comprise the data by keeping those change points that yield low probabilities. Data from the Ocean
Drilling Program were analysed, where a high correlation between the available core-log lithology interpretation and the statistical
segmentation was observed. Results show that the proposed algorithm can be used as an auxiliary tool in the analysis and interpretation
of geophysical log data for the identification of lithology units and sequences. 相似文献
993.
降水入渗补给量随地下水埋深变化的实验研究 总被引:1,自引:0,他引:1
利用冉庄8m定埋深地中蒸渗仪的观测资料,根据蓄满产流理论,采用分层计算还原的方法,研究降水入渗补给量随地下水埋深的变化规律。揭示了最佳埋深和稳定点的形成机理。在试验条件下,最佳埋深出现在3m左右,降水入渗补给量随地下水埋深的增大而减小,6m以后趋于稳定。 相似文献
994.
An assessment of Bernese GPS software precise point positioning using IGS final products for global site velocities 总被引:2,自引:1,他引:2
We assess the use of precise point positioning (PPP) within the Bernese GPS software (BSW) Version 5.0 over the period from
2000 to 2005. In our strategy, we compute a set of daily PPP solutions for international GNSS service (IGS) reference frame
(IGb00) sites by fixing IGS final satellite orbits and clock products, followed by a Helmert transformation of these solutions
into ITRF2000, forming a set of continuous position time series over the entire time span. We assess BSW PPP by comparing
our set of transformation parameters with those produced by the IGS analysis centre coordinator (ACC) and our position time
series with those of the Jet Propulsion Laboratory (JPL) and the Scripps Orbit and Permanent Array Centre at the Scripps Institute
of Oceanography (SIO). The distributions of the north (N), east (E) and up (U) daily position differences are characterized
by means and SD of +2.2 ± 4.8, −0.6 ± 7.9 and +4.8 ± 17.3 mm with respect to JPL, and of +0.1 ± 4.4, −0.1 ± 7.4 and −0.1 ± 11.8 mm
with respect to SIO. Similarly, we find sub-millimetre mean velocity differences and SD for the N, E and U components of 0.9,
1.5 and 2.2 mm/year with JPL, and of 1.2, 1.6 and 2.3 mm/year with SIO. A noise analysis using maximum likelihood estimation
(MLE) shows that when estimating global site velocities from our position time series, the series need to be on average up
to 1.3 times longer than those of JPL and SIO, before an uncertainty of less than 0.5 mm/year is obtained. 相似文献
995.
基于广义点理论的多基线影像钣金件3D重建与尺寸检测 总被引:1,自引:0,他引:1
采用沿CAD模型在影像中投影的外轮廓边缘点统计与最邻近直线广义点平差迭代相结合的方法,实现了钣金件初始方位的2D-3D自动定位。提出利用影像上的直线信息进行广义点平差,并基于多基线影像对工业钣金件进行高精度三维重建和尺寸误差检验,给出了带端点约束条件的多基线影像广义点摄影测量平差模型,并验证了其有效性。 相似文献
996.
997.
A new convenient combinatorial method is developed here to derive the invariant points in multisystem closed nets – the absent phase substitution (APS) method. It substantially simplifies the derivation of the closed nets in multisystems with many components and phases. For the multisystems whose total phase number (NPS) ≤ twice the number of the absent phases (m) in an invariant assemblage, the method can yield regular closed nets with or without globally absent phases; for other multisystems, the method can yield the regular closed nets with globally absent phases. As examples, the APS method was used to predict: (1) the regular closed nets of unary to quinary n + 4‐phase multisystems, unary 6‐phase multisystem and ternary 8‐phase multisystem; (2) the basic properties of the regular closed nets of the quaternary and quinary multisystems with n + 4 and n + 5 phases. Two multisystems were chosen to demonstrate how to select a realistic closed net from the numerous possible closed nets of a complex multisystem, and how to derive a realistic partially closed‐net, closed‐net‐diagram and the related realistic straight‐line‐net‐diagram. Comparisons of our APS method for the derivation of complicated closed nets with other methods indicate that this method is much simpler and more efficient. 相似文献
998.
从以往的资料看出,太阳系天体中不同观测对象对天球参考架零点改正的权重是不同的,以不同的小行星为观测对象,其零点改正的结果之间也有较大的差异,因为它们的轨道根数是不相同,本文利用最小二乘法方法分析了不同类型轨道的小行星在测定E和D改正时最或然值的偏差量以及必须满足的观测条件。此工作是为今后有效地选取合适的小行星观测来测定零点改正作准备;同时,这一方法也能够分析实测所得到的E和D的精度 相似文献
999.
数字海图点群状特征的识别、量测与综合 总被引:1,自引:0,他引:1
空间分布特征的保持是点群自动综合的核心和难点所在,为此,本文定义了4个参量:分布范围、分布密度、分布中心和分布轴线,来描述点群目标的结构化信息。利用Delaunay三角网和Voronoi图两种模型,着重探讨了点群分布特征的识别和量测问题,并在识别与量测的基础上,通过Voronoi图的动态构建,给出了点群自动综合模型,通过实际岛群数据的检测,证明了模型的正确性与可行性。 相似文献
1000.