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161.
The purpose of this paper is to describe a mathematical and computer model that has been developed by TransCanada for TransCanada
Pipelines (TCPL) and for the Canadian Gas Potential Committee (CGPC) for future Canadian natural gas resource assessment work.
It was developed in the contexts of developing a gas supply model for forecasting future Canadian gas supply for TCPL and
of improving the CGPC's assessment methodologies and software.
The model developed in this paper integrates two discovery process models used by the CGPC and solves the economic truncation
problem for semi-mature to mature plays. It is based on applying techniques developed by G. M. Kaufman and J. D. Fuller and
colleagues in new ways which extends the work of these authors.
This model has a number of important advantages including: fast computational speed, integration of parametric and nonparametric
statistical approaches, integration of the Kaufman and others model and the Arps-Roberts model, overcoming a PETRIMES limitation
of a maximum of 1000 samples, providing a finding rate forecast for economic analysis and providing a fresh look at solving
the economic truncation problem.
The details of the new Modified Arps-Roberts Model (now known as the Truncated Discovery Process Model or TDPM for short)
are discussed in this paper. 相似文献
162.
163.
蒋家沟泥石流输沙年际变化及其灾变预测 总被引:1,自引:0,他引:1
根据云南东川蒋家沟泥石流年输沙量的时序资料,分析了蒋家沟泥石流输沙的年际变化特征,发现历年输沙量变动幅度大,波动明显且年际变化频繁,用灰色系统理论的灾变预测方法,建立泥石流年输沙量的等维新息灾变预测模型,能够对未来可能出现的灾变年份进行较好的预测。在前期研究基础上,补充最新观测资料,建立了新的灾变时间序列和相应的等维新息灾变预测模型,使蒋家沟泥石流的年输沙量灾变预测得以连续进行,并对预测结果进行了检验,效果较为理想。 相似文献
164.
W. G. Strupczewski K. Kochanek S. Weglarczyk V. P. Singh 《Stochastic Environmental Research and Risk Assessment (SERRA)》2005,19(4):280-291
Robustness of large quantile estimates to the largest element in a sample of methods of moments (MOM) and L-moments (LMM) was evaluated and compared. Quantiles were estimated by log-logistic and log-Gumbel distributions. Both are lower bounded and two-parameter distributions, with the coefficient of variation (CV) serving as the shape parameter. In addition, the results of these two methods were compared with those of the maximum likelihood method (MLM). Since identification and elimination of the outliers in a single sample require the knowledge of the samples parent distribution which is unknown, one estimates it by using the parameter estimation method which is relatively robust to the largest element in the sample. In practice this means that the method should be robust to extreme elements (including outliers) in a sample.The effect of dropping the largest element of the series on the large quantile values was assessed for various coefficient of variation (CV) / sample size (N) combinations. To that end, Monte-Carlo sampling experiments were applied. The results were compared with those obtained from the single representative sample, (the first order approximation), i.e., consisting of both the average values (Exi) for every position (i) of an ordered sample and the theoretical quantiles based on the plotting formula (PP).The ML-estimates of large quantiles were found to be most robust to largest element of samples except for a small sample where MOM-estimates were more robust. Comparing the performance of two other methods in respect to the large quantiles estimation, MOM was found to be more robust for small and moderate samples drawn from distributions with zero lower bound as shown for log-Gumbel and log-logistic distributions. The results from representative samples were fairly compatible with the M-C simulation results. The Ex-sample results were closer to the M-C results for smaller CV-values, and to the PP-sample results for greater CV values. 相似文献
165.
海水中铜离子对氨基酸—粘土体系液—固界面作用的影响 总被引:2,自引:0,他引:2
用E(%)-pH曲线法实验研究了海水中三元表面络合物的形成和构型。通过海水中金属铜离子对氨基酸—粘土界面作用的E(%)-pH曲线影响的研究,发现曲线具有“单向上移”的规律,表明甘氨酸、天冬氨酸—铜离子—高岭土三元体系在实验条件下主要形成(Ⅰ)型三元表面络合物即≡S—O—M—L。该系列论文另一部分已研究氨基酸对金属离子—粘土体系的影响,证明可形成(Ⅱ)型三元表面络合物即≡S—O—L—M。据此可以推测(Ⅰ)型和(Ⅱ)型在某一条件下可以转变构型,其中间构型可能即是Leckie等提出的环形三元表面络合物。 相似文献
166.
167.
Jin Xueshen Jin Yanping Zhao Jun and Dai YinghuaSeismological Bureau of Hebei Province Shijiazhuang China 《中国地震研究》1995,(3)
Based on the site historical earthquake data,a method of seismic risk analysis is presented.Once the frequency of earthquake response intensity and the relative value showed a logarithmic linear,the maximum similarity method would be used to obtain β,λ,and Imax,and also achieve the results of risk analysis on each site.At the same time,the "logic tree" method can be used to calibrate the uncertainty of the risk on each site.Then the final results of risk analysis indicate that this method is feasible,particularly for the sites showing intensity anomaly. 相似文献
168.
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170.