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961.
The cooling and humidifying effects of urban parks are an essential component of city ecosystems in terms of regulating microclimates or mitigating urban heat islands(UHIs).Air temperature and relative humidity are two main factors of thermal environmental comfort and have a critical impact on the urban environmental quality of human settlements.We measured the 2-m height air temperature and relative humidity at the Beijing Olympic Park and a nearby building roof for more than 1 year to elucidate seasonal variations in air temperature and relative humidity,as well as to investigate the outdoor thermal comfort.The results showed that the lawn of the park could,on average,reduce the air temperature by(0.80±0.19)℃,and increase the relative humidity by(5.24±2.91)% relative to the values measured at the building roof during daytime.During the nighttime,the lawn of the park reduced the air temperature by(2.64±0.64)℃ and increased the relative humidity by(10.77±5.20)%.The park was cooler and more humid than surrounding building area,especially in night period(more pronounced cooling with 1.84℃).Additionally,the lawn of the park could improve outdoor thermal comfort through its cooling and humidifying effects.The level of thermal comfort in the park was higher than that around the building roof for a total of 11 days annually in which it was above one or more thermal comfort levels(average reduced human comfort index of 0.92)except during the winter.  相似文献   
962.
水源热泵系统中地下水流贯通及其对温度场的影响   总被引:3,自引:0,他引:3  
利用含水层储能的一般特点,提出流贯通;分析流贯通和热贯通的相互作用、相互影响及对工程实际的意义;并基于地下水水热运移的基本原理,建立地下水流动和热量输运的耦合数值模型。在此基础上对沈阳某场地水源热泵工程的运行进行流场及温度场的数值模拟分析,给出产生流贯通的依据,即利用水力坡度定量的判断流贯通发生与否;当水力坡度变化非常小、可忽略不计时,认为含水层出现流贯通;进而研究抽、灌量对流贯通的影响,发现抽、灌量越大,则出现流贯通时间越短;而大量的抽、灌量更容易发生流贯通,进而会引起热贯通的发生。在实际工程中可降低抽、灌水量,在条件许可的情况下可提高抽、灌井的间距,并可在抽、灌井运行一个周期后调整抽灌井位置,以减少热贯通的发生。  相似文献   
963.
The performance of the ensemble Kalman filter (EnKF) for continuous updating of facies location and boundaries in a reservoir model based on production and facies data for a 3D synthetic problem is presented. The occurrence of the different facies types is treated as a random process and the initial distribution was obtained by truncating a bi-Gaussian random field. Because facies data are highly non-Gaussian, re-parameterization was necessary in order to use the EnKF algorithm for data assimilation; two Gaussian random fields are updated in lieu of the static facies parameters. The problem of history matching applied to facies is difficult due to (1) constraints to facies observations at wells are occasionally violated when productions data are assimilated; (2) excessive reduction of variance seems to be a bigger problem with facies than with Gaussian random permeability and porosity fields; and (3) the relationship between facies variables and data is so highly non-linear that the final facies field does not always honor early production data well. Consequently three issues are investigated in this work. Is it possible to iteratively enforce facies constraints when updates due to production data have caused them to be violated? Can localization of adjustments be used for facies to prevent collapse of the variance during the data-assimilation period? Is a forecast from the final state better than a forecast from time zero using the final parameter fields?To investigate these issues, a 3D reservoir simulation model is coupled with the EnKF technique for data assimilation. One approach to enforcing the facies constraint is continuous iteration on all available data, which may lead to inconsistent model states, incorrect weighting of the production data and incorrect adjustment of the state vector. A sequential EnKF where the dynamic and static data are assimilated sequentially is presented and this approach seems to have solved the highlighted problems above. When the ensemble size is small compared to the number of independent data, the localized adjustment of the state vector is a very important technique that may be used to mitigate loss of rank in the ensemble. Implementing a distance-based localization of the facies adjustment appears to mitigate the problem of variance deficiency in the ensembles by ensuring that sufficient variability in the ensemble is maintained throughout the data assimilation period. Finally, when data are assimilated without localization, the prediction results appear to be independent of the starting point. When localization is applied, it is better to predict from the start using the final parameter field rather than continue from the final state.  相似文献   
964.
965.
王瑜  周丽云 《中国区域地质》2008,(12):2014-2019
从同位素年代学发展到构造年代学,中间必须经历热年代学、构造-热年代学、变形年代学等阶段。同位素年代学只是提供简单的地质事件年龄,热年代学同时赋予了地质事件温度和年龄信息,而构造年代学则强调地质或构造过程中时间-空间的四维演化过程。构造年代学使年龄数据的科学意义除了时间外,还有温度、地壳深度变化、是否有流体参与等多重意义,它涉及到多维空间的变化:时间、温度、水平方向的二维变形、垂直方向的变形等。在现有技术和认知水平的条件下,强调指出了从变形年代学到构造年代学的发展中要注意的一些关键问题,而回归传统地质、以野外变形为基础的变形年代学研究是构造年代学发展的前提。  相似文献   
966.
Failures Associated with the 2004 Mindulle Typhoon in Taiwan   总被引:2,自引:0,他引:2  
On July 2, 2004, a 2000-km southwest air current following the Mindulle Typhoon caused serious damages to infrastructures in Taiwan. The disaster resulted in extensive geological and structural failures, mainly as a result of debris flow. Some of the sites were subjected to types of repeated failures compared to previous typhoons. Some structural failures were attributed to geotechnical failures. It is decided to document and identify causes for some of these major failures triggered by typhoons. The case history showed significant implications to future disaster prevention and management works. New challenges were posed in geotechnical engineering design in encountering rainfall-induced failures.  相似文献   
967.
The first attempted republican map of present-day Colombia remained unachieved. Francisco José de Caldas worked on it since 1797 and, come the revolution and Nueva Granada's republican inception, he prepared two successive cartouches to introduce it: the first one in 1811, the latter in 1815. Finally entitled Provincias de la Nueva Granada, Caldas's map remains understudied. In this article, I establish its basic cartographic parameters, discuss the political context of its unfinished making and link it to its pertinent cartographic precedents.  相似文献   
968.
我国云南腾冲地区地热资源丰富,对地热资源进行定量的预测评价势在必行。而以遥感为手段进行地表温度的反演是地热研究的重要方法。本文利用ETM数据的Band6热红外通道,对工作区进行温度反演并通过消除阴影影响对反演温度进行修正使得温度差异较大的情况得到改善,减少了太阳照射造成的温差影响。结果表明,研究区地表温度分布主要有3个区域;通过温度反演结果与已知地热点叠加分析,选取14~21℃为进行地热预测评价的有利区间。  相似文献   
969.
《坤輿万国全图》与《利玛窦中国札记》中外译本考疑   总被引:1,自引:0,他引:1  
金尼阁编译的《利玛窦中国札记》多种欧洲文字版本之间存在翻译差异,而300年后出版的英译本和中译本与原文存在严重错漏。600页的札记,利玛窦只用不到两页的篇幅叙述测绘《坤輿万国全图》一事,连实际比例尺的描述也不清楚。利玛窦承认没有见过其他的版本,"六幅版"地图出现在南京或北京,个别欧洲文字翻译版本不一,《坤輿万国全图》究竟是在南京还是北京完成的也有疑问。《利玛窦中国札记》用的是中国传统的测绘术语,指出地图的错误是针对西方地图而不是中国地图。《坤輿万国全图》中一半的中文地名,当时欧洲地图没有对应。1593年,利玛窦尚未制作《坤輿万国全图》,"六幅版"中文世界地图已出现在南京。因此,《坤輿万国全图》原本早已存在,《坤輿万国全图》应是郑和时代(1405—1433)大航海的成果,中国的地图学,不是西学东渐,甚至有可能是中国的世界地理与地图学流传到西方。世界地图史应该还原中国对地理大发现与地图学的贡献。  相似文献   
970.
应用 1988年和 1992年福州市卫星图像 ,对福州市热岛效应进行动态研究 ,结果表明 :随着城市建设的发展 ,原热岛范围内高温区增加 ,热岛范围明显扩大 ,尤其是市区东部施展最快 ,在 1988~ 1992这 4年中福州的热岛范围向东扩展了约 15km2 ,同时热岛外围小热岛也不断涌现。在这些动态变化特征的基础上 ,本文分析了福州市热岛效应动态变化的原因以及减轻热岛效应影响的具体措施。  相似文献   
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