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991.
基于传统的古构造应力场重建方法,依据元谋?昔格达断裂及其附近的构造形迹,恢复了区域构造应力场.结果表明,研究区自上新世以来,主要受早期(中更新世之前)的NNE-SSW向和晚期(中更新世以来)的NNW-NWW向水平主压应力作用;而江边?下雷弄、化同?秧田井、一平浪?罗川一带的元谋?昔格达断裂晚第四纪倾滑特征与相应段落处的... 相似文献
992.
针对我国铁矿矿产资源储量数据一直处于分散状态,没有发挥其应有价值的实际情况,对全国性铁矿资源潜力数据的共享与应用进行了深入研究.系统地梳理了以矿区作为基本单元的全国2 026个大中型铁矿的资源潜力信息,基于Oracle Spatial和面向对象特性建立了可兼容其他矿种的铁矿空间数据模型,以Web服务为基本组件的面向服务体系结构搭建系统基础框架,采用面向对象程序设计语言实现目标系统.结合系统对我国铁矿类型、铁矿资源潜力预测等进行了分析,统计结果表明:预测铁矿资源潜力为600.233 2 亿t,预测有资源潜力的矿区为389处,15个铁矿找矿远景区的潜在资源量为378 亿t.这种松耦合的系统框架易扩展与集成,从而可方便地为其他系统提供数据支撑. 相似文献
993.
ZHOU Jia XIAO Haifeng SHANG Jincheng ZHANG Xuelin 《中国地理科学(英文版)》2007,17(4):304-310
Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongjiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis (PCA) to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process (AHP) method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990-2002, with a turn in 1998, and the development could be sustainable, the status trend was more harmonious in 1999-2002. 相似文献
994.
河南内乡—淅川地区具有一完整的边缘成矿体系。应用边缘成矿理论,通过野外对该区控矿要素的实际调研和室内对比分析,提出了豫西南内乡—淅川地区边缘成矿体系的新认识。一级成矿边缘为华北板块与扬子板块边缘对接处(山阳—西峡断裂带两侧),控制了两个跨省大型成矿带的形成;二级成矿边缘为区域深大断裂边缘,控制区域成矿带形成;三级成矿带边缘为岩体边缘、次级断裂带边缘和地层交界面等,控制矿田、矿床的形成;四级成矿边缘为岩体边缘不同岩相分界面、不同岩性层间面和构造形态、产状变化处。不同边缘交叉、叠合地段是成矿最有利地段。研究表明,边缘成矿体系的形成与地质异常事件密切相关,板块活动、区域构造、火山、岩浆侵入、沉积环境演化是边缘成矿体系形成的主导因素。根据边缘成矿规律进行了成矿预测,指出主要找矿方向和有利找矿区段(靶区)。 相似文献
995.
该文基于标准化自协方差函数的组合算法计算了阿仑方差、哈达玛方差的重叠和非重叠形式以及改进阿仑方差、时间方差的等效自由度,并用经验公式计算了总方法估计的等效自由度,在此基础上对各种方差估计不同噪声情况下的等效自由度进行了比较分析,得出如下结论,总方法估计的等效自由度大于相应非总方法估计的等效自由度,重叠和非重叠阿仑方差估计的等效自由度大于相应哈达玛方差估计的等效自由度;对非重叠估计而言,噪声的频率越低,其等效自由度越大;而相应的重叠估计和总方法估计与之相反,噪声的频率越高,其等效自由度越大,这也说明重叠估计和相应的总方法估计对高频噪声等效自由度的提高优于低频噪声. 相似文献
996.
焦宝文 《测绘与空间地理信息》2021,44(z1):198-199,205
当工程测量投影长度变形超限时,一般要建立独立坐标系.基于高斯投影3°带,以测区抵偿高程面为投影面建立独立坐标系是比较常用的方法.通过实例,本文对投影于测区抵偿高程面上的坐标计算公式进行了详细推导,仅供同行们参考. 相似文献
997.
998.
Public weather services are trending toward providing users with probabilistic weather forecasts, in place of traditional deterministic forecasts. Probabilistic forecasting techniques are continually being improved to optimize available forecasting information. The Bayesian Processor of Forecast (BPF), a new statistical method for probabilistic forecast, can transform a deterministic forecast into a probabilistic forecast according to the historical statistical relationship between observations and forecasts generated by that forecasting system. This technique accounts for the typical forecasting performance of a deterministic forecasting system in quantifying the forecast uncertainty. The meta-Gaussian likelihood model is suitable for a variety of stochastic dependence structures with monotone likelihood ratios. The meta-Gaussian BPF adopting this kind of likelihood model can therefore be applied across many fields, including meteorology and hydrology. The Bayes theorem with two continuous random variables and the normal-linear BPF are briefly introduced. The meta-Gaussian BPF for a continuous predictand using a single predictor is then presented and discussed. The performance of the meta-Gaussian BPF is tested in a preliminary experiment. Control forecasts of daily surface temperature at 0000 UTC at Changsha and Wuhan stations are used as the deterministic forecast data. These control forecasts are taken from ensemble predictions with a 96-h lead time generated by the National Meteorological Center of the China Meteorological Administration, the European Centre for Medium-Range Weather Forecasts, and the US National Centers for Environmental Prediction during January 2008. The results of the experiment show that the meta-Gaussian BPF can transform a deterministic control forecast of surface temperature from any one of the three ensemble predictions into a useful probabilistic forecast of surface temperature. These probabilistic forecasts quantify the uncertainty of the control forecast; accordingly, the performance of the probabilistic forecasts differs based on the source of the underlying deterministic control forecasts. 相似文献
999.
1000.