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71.
Sun  Han  Wang  Hai  Hu  Xueyuan 《Natural Resources Research》2020,29(6):3581-3598

Achieving the coordinated development of mineral exploitation and the water environment (the mine–water system, MWS) is an urgent difficulty in the construction of China’s ecological civilization. Based on the theory of synergy, a synergetic model was used to construct a network of the MWS, and then, social network analysis was applied to study the network characteristics for ten provinces of the Yangtze River Economic Belt. The research results show that the natural water system has always been at the center of the MWS, and water conservancy construction is particularly critical. However, the synergistic effect is not strong between the water environmental stress system and other systems, and as a result, the water environment is under great pressure. Among the crucial factors, the discharge of wastewater and solid waste is at the core of the network and directly affects the coordinated development trend of the MWS. However, the sustainable development of the water environment is better achieved by the treatment of solid waste than by the control of wastewater discharge. Generally, the synergistic relationship based on the natural water system is very important. At the same time, the core role of the water environmental protection system should be strengthened by adjusting sequence parameters to promote the overall coordinated development of the MWS.

  相似文献   
72.
Located on the centre of ice drainage range, the highest Dome Argus (Dome A) of East Antarctic Ice Sheet (EAIS), could be represented as an ideal site for deep ice cores drilling containing oldest paleo-climate records. To select a suitable drilling site for deep ice core, it needs gather all information pertaining to the local meteorology, ice sheet landforms, ice thickness, subgla- cial topography of bed rocks, ice velocity, internal structures of ice sheet, etc. Based on the International Partnerships in Ice Core Sciences (IPICS), we present recent achievement of glaciological research and its perspective at Dome A in this paper. We system- atically discussed the merits and possible ventures of potential drilling sites around Dome A. Among all the candidates, we find that the Chinese Antarctic Kunlun Station is the best site for and assess further the possibility to obtain a replicate core for carrying out the first deep ice core drilling campaign. We emphasize studying dynamics and evolution of climate change.  相似文献   
73.
针对矿山开发秩序混乱的问题, 通过描述矿山开发要素与采矿权的空间位置关系, 介绍和设计了点面、面面拓扑关系的判定及矿山开发秩序的检验;以2010年QuickBird遥感影像为数据源, 对宁武矿区进行了矿山监测, 基于空间数据库引擎和嵌入式GIS组件, 实现了矿山开发要素的空间拓扑关系判定和查询, 为矿山监测提供了有效的参考信息。  相似文献   
74.
用NCEP/NCAR月平均再分析资料对南亚高压和对流层上层西风急流的季节变化及盛夏两类型态进行对比。结果表明,南亚高压和西风急流中心都有从冬到夏的西移北进和从夏到冬的东退南撤,急流中心位于南亚高压中心北侧。东亚夏季风盛行期间南亚高压中心的北移提前于西风急流中心的北移,二者的强度呈反相的季节变化。一般情况下,伊朗高压对应西部急流型,青藏高压对应东部急流型。典型东、西部急流年份中高纬气温及高度场的差异表明气压梯度力强弱对比是急流东西型变化的主要原因,南亚高压的位置基本上决定了急流中心的型态,但由于南亚高压具有"趋热性",而急流的移动符合热成风的规律,因而二者的热力影响机制有所不同。  相似文献   
75.
研究了可用于多传感器组合导航系统的两级分布式最优融合算法,以理论的形式证明了在有、无信息反馈的情况下最终的融合结果是等价的与最优的。仿真结果在验证上述理论的情况下,也说明了来自融合中心的反馈信息可明显提高子滤波的滤波性能。  相似文献   
76.
针对不同导航传感器存在的采样率不同步(或尺度不同),提出了一种基于状态方程多尺度变换的异步多传感器组合导航系统信息融合算法。仿真结果表明,本算法不仅具有较好的实时性,而且具有较好的融合精度。  相似文献   
77.
据索尔库都克铜-钼矿床地化特征探讨其成因类型   总被引:6,自引:0,他引:6  
索尔库都克铜(钼)矿床,主要赋存于辉石闪长玢岩外接触带的安山质岩石中。除Cu,Mo外,Ca,Fe,Mn,Pb,Zn,Ti,Cr,Ni和Co含量也较高。Si,Na,K和REE含量最低,具一套与中基性岩有关(矿床)的元素组合特征。索尔库都克铜(钼)矿的同位素特征与辉石闪长玢岩相近,类似美洲的依尔·萨尔瓦多斑岩铜矿。因此,笔者认为该矿是与辉石闪长玢岩有关的斑岩型矿床。  相似文献   
78.
Gold deposits of the meso-epithermal carbonate type were first proposed based on the study of the Baguamiao gold deposit.This new type of gold deposits has many unique characteristics as follows:(1)Obviously strata-bound.The gold deposits are hosted in Middle Devonian turbidite formations;(2)Structrually controlled.Struc-ture is an important factor leading to metallogenesis of this type of gold deposits.The shape and distribution of orebodies are controlled by byittle-ductile shear zones;(3)Multi-stage wall-rock alteration.According to the characteristics of mineral assemblage,gold mineralization can be classified into three stages in association with various wall-rock al-terations.Wall-rock alterations closely genetically related to the gold mineralization are ankerization ,silicification,pyrrhotization and pyritization ;(4)Mineral compositions of the orebodies are mainly pyrrhotite,pyrite,marcasitolite,chalcopyrite,quartz,ankerite,and sericite.Gold mineralization is associated closely in space and time with iron sulfides;(5)Rare elements and REE in ores are low in contents relative to those of the crust.Au content varies from 1.91g/t to 11.15g/t ,averaging 5.5g/t;(6)Studies of sulfur,hydrogen,oxygen and carbon isotopes in main gangue minerals (quartz and ankerite)indicate that fluids and ore-forming materials came from deep-seated sources;(7)Three types of inclusions are recognized in terms of their composition and the vapor amounts of inclusions.The homogenization temperatures of inclusions range from 210℃to 310℃,averaging 230℃,showing that this type of gold deposits belongs to the meso-epithermal type;(8)Metallogenic age of this type of gold deposits is similar to that of the collision between the Yangtze Plate and the North China Plate,indicating that gold deposits of this type are genetically related to continental-margin plate activity.  相似文献   
79.
一种低成本、低精度SINS/GPS组合导航系统及试验研究   总被引:3,自引:0,他引:3  
在SINS(捷联式惯性导航系统)与GPS组合时,航向角的可观测性较弱,经过卡尔曼滤波后,航向角误差虽有所改善,但仍呈发散趋势,当采用低成本、低精度SINS时,该趋势进一步加剧。为了抑制该发散趋势,针对某型低成本、低精度SINS硬件组成(包括AHRS(姿态和航向参考系统)与IMU(惯性测量器件))的特点,提出了利用AHRS代替SINS航向角信息的方法。实际静态与动态试验表明,利用该方法可有效地抑制组合系统航向角的发散趋势,定位精度较高。  相似文献   
80.
唐学远  张占海  孙波 《极地研究》2006,18(4):290-300
数值模拟南极冰盖是提升人们认识南极冰盖演化行为的重要手段。通过数值模拟研究可以揭示某些观测数据包含的冰盖物理机理以及在缺乏观测数据的情形下预测冰盖的演化行为。本文在综述南极冰盖数值研究国际进展的基础上,分析了南极冰盖数值模拟方面几个主要模型的特点,特别针对南极冰盖的三维数值模拟展开讨论,分析并探讨了冰盖数值模拟可能会遇到的潜在不稳定源以及在拓展模型研究范围时会遇到的障碍。对目前三维冰盖数值模拟存在的几个问题进行了讨论,并对未来发展进行了展望。  相似文献   
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