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101.
如何对传感器资源进行重新组合并用于发现来实现高级的信息共享是目前亟待解决的问题。本文针对目前传感器的建模现状和发现机制现状,选择传感器模型语言(Sensor ML)实现传感器信息的建模。针对Sensor ML用于发现机制的Profile规则,提出了面向处理的传感器抽象模板建模方法。并且使用传感器实例注册(Sensor Instance Registry,SIR)客户端传感器信息模型。基于本文提出的方法,采用自主设计开发的传感器建模软件SensorModel完成了对传感器的快速实例化建模,应用SIR客户端完成了对所建传感器信息模型有效的注册和发现。  相似文献   
102.
In recent years, El Nio Modoki (a type of pseudo-El Nio) has been distinguished as a unique large-scale ocean warming phenomenon happening in the central tropical Pacific that is quite different from the traditional El Nio. In this study, EOF analysis was used to successfully separate El Nio and El Nio Modoki. The abilities of the NINO3 index, NINO3.4 index, NINO1+2 index and NINO4 index in characterizing El Nio were explored in detail. The resulting suggestion was that, comparatively, NINO3 is the op...  相似文献   
103.
针对面板堆石坝摊铺层表面及测量机器人采集摊铺层离散数据密且精度高等特征,利用径向神经网络方法,采用复二次函数作为径向基,根据数理统计理论和逐步趋近法自适应优选平滑因子拟合摊铺层高程,以达到与实际高程的最佳吻合。以某面板堆石坝的测量机器人采集的数据为例,对该方法进行了验证。结果表明,其拟合精度明显优于常规拟合方法,更加适合面板堆石坝摊铺层表面的高程拟合。  相似文献   
104.
Classical 3D/4D variation fusion is based on the theory that error follows Gaussian distribution. When using minimization iteration, the gradient of objective function is involved, and the solution of which requires the continuity of data. This paper adopted the extended classical 3D/4D variation fusion method, and explicitly applied the prior knowledge, which was based on L1-norm, as regularization constraint to the classical variation fusion method. Original data was firstly projected into the wavelet domain during the implementation process, and new fusion model was adopted for data fusion in wavelet space, then inverse wavelet transform was used to project the result to the observation space. Ideal experiment was carried out by using linear advection-diffusion equation as four-dimensional prediction model, which made a hypothesis of the discontinuity with the data between background and observation, and that meant the derivatives between left and right were not equal on some points. The result of the experiment showed that the method adopted here was practicable. A further research was also done for multi-source precipitation fusion. Firstly, CMORPH inversion precipitation data were corrected through PDF (Probability Density Function, PDF) matching method based on GAMMA fitting function. Then corrected data was fused with the observation one. By comparison with the reference field, the result showed that this method can keep some outliers better, which might represent certain weather phenomenon. The L1-norm regularization variation fusion in this paper provided a possible way to deal with discrete data, especially for jump point.  相似文献   
105.
岩溶动力系统中的生物作用机理初探   总被引:24,自引:1,他引:24  
岩溶动力系统是地球表层系统的重要组成部分。生物是地球表层系统中最活跃的地质营力之一 ,它在岩溶动力系统中扮演着重要的角色。地质历史时期 ,生物圈大气圈界面上 ,生物通过植物的光合同化、动植物分泌 ,使大气圈中的CO2 不断转移到碳酸盐岩中 ,形成岩溶发育的物质基础 ,并成为全球最大的碳库 ;生物圈水圈界面上 ,生物形成的生物 (微 )环境改变了水循环的强度和方向 ,并影响岩溶发育 ;生物圈岩石圈界面上 ,生物通过生物物理、生物化学过程 ,殖居碳酸盐岩之上 ,并以之为生存依托 ,生物的新陈代谢过程使碳酸盐岩岩石圈活化 ,使其积极参与全球碳循环。  相似文献   
106.
黄河源区降水与径流过程对ENSO事件的响应特征   总被引:19,自引:10,他引:19  
根据最新季分辨率ENSO指数序列所确认的近40年多来所发生的20次ENSO事件,并确定了每次ENSO事件强度及其影响年,通过对相应年份黄河源区降水与径流距平变化值的对比,分析了降水与径流过程对ENSO事件响应的统计规律;ENSO事件与黄河源区降水与径流年际波动变化有很好的相关性,这种相关性与ENSO事件的性质强弱,发生季节以及持续时间等有关。一般夏秋季暖事件无论强弱均使影响年降水减少,发生于春季的中等强度暖事件使发生年降水呈负距平,影响年降水呈增加趋势,冷事件与暖事件对降水的影响正好相反;暖事件对应年份黄河源区径流量减少,而冷事件则使其增加,随着20世纪90年代以来暖事件发生频率的增加,径流呈现持续减少。  相似文献   
107.
40a来江河源区的气候变化特征及其生态环境效应   总被引:68,自引:19,他引:68  
通过江河源区分布的5个气象台站有关气温与降水的多年数据,分析了近40a来江河源区的气候变化特征,结果表明,近40a来江河源区气候变化的总趋势是气温升高,降水量增加,但降水量的增加主要体现在春季降水和近15a来冬季降水的明显增加上,对植被生长起重要作用的夏季降水量却呈明显减少趋势;江河源区20世纪80年代10a平均气温比50年代高0.12~0.9℃,大部分地区高于0.3℃,属于青藏高原高温区或升温幅度最大的地区之一,平均升温0.44℃,明显比全国平均升温0.2℃要高出一倍,在这种背景下,与植被生长关系密切的4、5月和9月气温呈现持续下降态势,江河源区脆弱的生态环境体系对气候的这种变化响应强烈,冰川退缩,多年冻土消融加剧,导致大范围高寒草甸与草原被植退化。  相似文献   
108.
东秦岭基底组成与构造区划分   总被引:2,自引:1,他引:2  
从基本地质组成上,东秦岭构造基底可划分为华北,北秦岭、佛坪、白水江,汉南和武当六大地体,不同地体的基底组成有明显差异,它们先后于中-晚元古在不同时间段,通过不同的方式而拼合为统一的华夏泛大陆,从而完成东秦岭从原始地壳生长到典型板块构造体制上的转换,是全球Rodinia事件在本区的具体表现。  相似文献   
109.
The Izu-Ohshima-Kinkai earthquake (M = 7.0 on the Richter scale) occurred at 12h24 Japan Standard Time on 14 January 1978 in Sagami Bay, and caused hazards in the eastern to central Izu Peninsula. The meizoseismal zone extended 15 km from east to west by 20 km from north to south.

The aftershock zone shifted westward to the interior of the peninsula. The largest aftershock (M = 5.8) struck the central to western part of the peninsula on 15 January, causing severe damage in its mountainous terrain.

Most of the hazards related to slope failures of sea cliffs, river cliffs and road cuttings of convex vertical section with the upper parts sloping gently and the lower parts steeply.

Large slope failures occurred close to the activated faults, indicating that the shocks and displacement were locally amplified along the activated faults.

In the meizoseismal zone, high embankments of roads and housing sites on natural slopes were damaged by slides and tension cracks between the embankment and natural ground.

Subsidence and tilting of retaining structures were generally observed. Damage to high concrete retaining walls of gravity type was due to the insufficient bearing capacity of the foundation soil. Any type of retaining structure, even if seismic-resistant, would be considered ineffective in case of failure of the back slope.

Buildings in the meizoseismal zone were damaged due to sliding of the underlying embankments and ground displacement due to the activated faults.

Falling rock blocks and sliding soil masses struck cars and houses close to the foot of cliffs and steep slopes, causing many deaths and injuries.

A number of tension cracks in the middle to upper parts of steep slopes and on the shoulders of road embankments threatened to cause secondary failures, rockfalls and avalanches during heavy rain.

At a gold and silver mine, the tailings dam of a concentration plant failed due to liquefaction of the tailings.

The above experience may throw some light on the possibility of seismic failures in mountainous countries in seismically active regions of the world.  相似文献   

110.
The organic-rich shale of the Shanxi and Taiyuan Formation of the Lower Permian deposited in a marine-continental transitional environment are well developed in the Ordos Basin, NW China, which is considered to contain a large amount of shale hydrocarbon resources. This study takes the Lower Permian Shanxi and Taiyuan shale collected from well SL# in the Ordos Basin, NW China as an example to characterize the transitional shale reservoir. Based on organic geochemistry data, X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FE-SEM) observations, the desorbed gas contents of this transitional shale were systematically studied and the shale gas potential was investigated. The results indicate that the Lower Permian Shanxi and Taiyuan shale has a relatively high total organic carbon (TOC) (average TOC of 4.9%) and contains type III kerogen with a high mature to over mature status. XRD analyses show that an important characteristic of the shale is that clay and brittle minerals of detrital origin comprise the major mineral composition of the marine-continental transitional shale samples, while the percentages of carbonate minerals, pyrite and siderite are relatively small. FE-SEM observations reveal that the mineral matrix pores are the most abundant in the Lower Permian shale samples, while organic matter (OM) pores are rarely developed. Experimental analysis suggests that the mineral compositions mainly govern the macropore development in the marine-continental transitional shale, and mineral matrix pores and microfractures are considered to provide space for gas storage and migration. In addition, the desorption experiments demonstrated that the marine-continental transitional shale in the Ordos Basin has a significantly potential for shale gas exploration, ranging from 0.53 to 2.86 m3/t with an average value of 1.25m3/t, which is in close proximity to those of terrestrial shale (1.29 m3/t) and marine shale (1.28 m3/t). In summary, these results demonstrated that the Lower Permian marine-continental transitional shale in the Ordos Basin has a significantly potential for shale gas exploration.  相似文献   
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