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71.
What potential effect do flexible mechanisms under the Kyoto Protocol have on energy efficiency, fuel switching and the development of renewable energy sources for the eight post-communist EU Member States that accessed in 2004? These countries are chief candidates for hosting Joint Implementation (JI) projects and for participating in international emission trading, which may assist the implementation and financing of projects in these target areas. The potentials and barriers to Joint Implementation are reviewed, as well as the conditions under which international emission trading can influence the energy use of the selling country. Different strategies adopted by the host countries towards the application of these instruments, and their impact on sustainable energy development, are examined. The article concludes that the Kyoto flexibility mechanisms may play a positive, but rather limited, role in the sustainable energy development of the region, but the barriers to Joint Implementation may shift the emphasis towards transactions under the framework of international emission trading. If innovative mechanisms are tied to sustainable development goals, this may mobilize the energyefficiency potentials of these countries. An attractive opportunity exists to achieve energy efficiency and emission reductions, utilizing the revenues from allowance sales through ‘green investment’ schemes. 相似文献
72.
淮河流域是中国南北气候重要的过渡带,气象灾害频繁发生。这里水网、农田、丘陵、山地、城镇密布,地-气作用复杂,干冷与暖湿空气时常交汇于此,造成局地或流域旱涝经常发生。淮河流域处于梅雨区,且是中国重要的农业生产基地,具有气象和水文综合观测系统,积累了长序列的气象和水文观测资料。因此,淮河流域是研究能量和水分循环的理想试验区。国家自然科学基金重大项目“淮河流域能量与水分循环试验和研究(HUaihe river Basin Experiment,简称HUBEX)”于1998、1999年夏在淮河流域开展了气象和水文联合观测试验。文中回顾了HUBEX试验的目的、观测网设计与布局,介绍了HUBEX推动下的淮河流域综合观测网的发展,总结了HUBEX观测试验对区域气候事件和暴雨等灾害性天气机理研究、提高模式模拟和预报能力及建立长期连续的气象观测数据集等方面的成果和作用。 相似文献
73.
Modeling the spread of subsurface contaminants requires coupling a groundwater flow model with a contaminant transport model. Such coupling may provide accurate estimates of future subsurface hydrologic states if essential flow and contaminant data are assimilated in the model. Assuming perfect flow, an ensemble Kalman filter (EnKF) can be used for direct data assimilation into the transport model. This is, however, a crude assumption as flow models can be subject to many sources of uncertainty. If the flow is not accurately simulated, contaminant predictions will likely be inaccurate even after successive Kalman updates of the contaminant model with the data. The problem is better handled when both flow and contaminant states are concurrently estimated using the traditional joint state augmentation approach. In this paper, we introduce a dual estimation strategy for data assimilation into a one-way coupled system by treating the flow and the contaminant models separately while intertwining a pair of distinct EnKFs, one for each model. The presented strategy only deals with the estimation of state variables but it can also be used for state and parameter estimation problems. This EnKF-based dual state-state estimation procedure presents a number of novel features: (i) it allows for simultaneous estimation of both flow and contaminant states in parallel; (ii) it provides a time consistent sequential updating scheme between the two models (first flow, then transport); (iii) it simplifies the implementation of the filtering system; and (iv) it yields more stable and accurate solutions than does the standard joint approach. We conducted synthetic numerical experiments based on various time stepping and observation strategies to evaluate the dual EnKF approach and compare its performance with the joint state augmentation approach. Experimental results show that on average, the dual strategy could reduce the estimation error of the coupled states by 15% compared with the joint approach. Furthermore, the dual estimation is proven to be very effective computationally, recovering accurate estimates at a reasonable cost. 相似文献
74.
通过在同一条测线上应用三种不同地震勘探手段(共偏移距地震反射法、横波反射法与高分辨率折射法)联合反演的方法,获得了测线控制地段内废黄河断层的确切位置、上断点埋深以及速度分布图像.探测结果表明:在薄覆盖层地区的断裂调查中,上述三种技术手段的联合反演要比单独使用其中任何一种手段更加可靠,并能从不同角度查明断层的位置、性质及其特征,为钻孔联合剖面位置的布设和钻孔深度的设计提供地震学依据.经高精度钻孔联合地质剖面证实,三种地震勘探方法反演得到的主要地层界面和构造特征都与钻孔联合地质剖面吻合较好.试验表明了上述三种地震勘探方法在基岩面埋深较浅地区联合反演的可行性以及地震勘探与钻孔联合地质剖面相结合的工作方法的有效性. 相似文献
75.
76.
In consideration of large uncertainties in severe convective weather forecast, ensemble forecasting is a dynamic method developed to quantitatively estimate forecast uncertainty. Based on ensemble output, joint probability is a post-processing method to delineate key areas where weather event may actually occur by taking account of the uncertainty of several important physical parameters. An investigation of the environments of little rainfall convection and strong rainfall convection from April to September (warm season) during 2009-2015 was presented using daily disastrous weather data, precipitation data of 80 stations in Anhui province and NCEP Final Analysis (FNL) data. Through ingredients-based forecasting methodology and statistical analysis,four convective parameters characterizing two types of convection were obtained, respectively, which were used to establish joint probability forecasting together with their corresponding thresholds. Using the ECMWF ensemble forecast and observations from April to September during 2016-2017, systematic verification mainly based on ROC and case study of different weather processes were conducted. The results demonstrate that joint probability method is capable of discriminating little rainfall convection and non-convection with comparable performance for different lead times, which is more favorable to identifying the occurrence of strong rainfall convection. The joint probability of little rainfall convection is a good indication for the occurrence of regional or local convection, but may produce some false alarms. The joint probability of strong rainfall convection is good at indicating regional concentrated short-term heavy precipitation as well as local heavy rainfall. There are also individual missing reports in this method, and in practice, 10% can be roughly used as joint probability threshold to achieve relative high TS score. Overall, ensemble-based joint probability method can provide practical short-term probabilistic guidance for severe convective weather. 相似文献
77.
78.
老寨湾金矿控矿层位时代及控矿因素新认识 总被引:2,自引:0,他引:2
矿区主要金矿化层为下奥陶统老寨组(O1l),而非下泥盆统坡松冲组。金矿化主要受断裂构造+岩浆活动+不整合面+岩性等多因素的综合控制,矿体富集的空间部位与断裂构造及深部岩浆活动有密切的关系。丰富和扩展了滇东南地区加里东不整合面控矿理论的内涵,明确矿区深部及外围找矿空间。 相似文献
79.
Local and Spatial Joint Frequency Uncertainty and its Application to Rock Mass Characterisation 总被引:1,自引:1,他引:0
Stability is a key issue in any mining or tunnelling activity. Joint frequency constitutes an important input into stability
analyses. Three techniques are used herein to quantify the local and spatial joint frequency uncertainty, or possible joint
frequencies given joint frequency data, at unsampled locations. Rock quality designation is estimated from the predicted joint
frequencies. The first method is based on kriging with subsequent Poisson sampling. The second method transforms the data
to near-Gaussian variables and uses the turning band method to generate a range of possible joint frequencies. The third method
assumes that the data are Poisson distributed and models the log-intensity of these data with a spatially smooth Gaussian
prior distribution. Intensities are obtained and Poisson variables are generated to examine the expected joint frequency and
associated variability. The joint frequency data is from an iron ore in the northern part of Norway. The methods are tested
at unsampled locations and validated at sampled locations. All three methods perform quite well when predicting sampled points.
The probability that the joint frequency exceeds 5 joints per metre is also estimated to illustrate a more realistic utilisation.
The obtained probability map highlights zones in the ore where stability problems have occurred. It is therefore concluded
that the methods work and that more emphasis should have been placed on these kinds of analyses when the mine was planned.
By using simulation instead of estimation, it is possible to obtain a clear picture of possible joint frequency values or
ranges, i.e. the uncertainty. 相似文献
80.
瑞利面波垂直-水平振幅比(或ZH振幅比)是一个随频率变化的函数,对于台站下方浅层地壳结构非常敏感,且具有和频散资料不同的深度敏感核,是传统频散反演方法的一个很好的补充,从而可以将基阶瑞利面波的ZH振幅比和面波频散数据联合起来更好地反演获得观测台站下方的速度结构.本文提出了基于邻域算法的面波频散曲线与ZH振幅比联合反演方法,我们进行了基于理论模型的模拟测试,证明了联合反演是一种更为可靠的反演方法,且能更好地约束浅层地壳结构.相比于频散曲线单独反演,联合反演不仅可以精确反演获得地壳的Vs结构,对分层地壳的Vp/Vs也能很好地约束.然后我们将联合反演算法应用于实际测量数据,获得了中国西南昆明台(KMI)下方更为准确的地壳横波速度结构及Vp/Vs模型. 相似文献