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111.
Each year across the USA, destructive weather events disrupt transportation and commerce, resulting in both loss of lives and property. Mitigating the impacts of such severe events requires innovative new software tools and cyberinfrastructure through which scientists can monitor data for specific severe weather events such as thunderstorms and launch focused modeling computations for prediction and forecasts of these evolving weather events. Bringing about a paradigm shift in meteorology research and education through advances in cyberinfrastructure is one of the key research objectives of the Linked Environments for Atmospheric Discovery (LEAD) project, a large-scale, interdisciplinary NSF funded project spanning ten institutions. In this paper we address the challenges of making cyberinfrastructure frameworks responsive to real-time conditions in the physical environment driven by the use cases in mesoscale meteorology. The contribution of the research is two-fold: on the cyberinfrastructure side, we propose a model for bridging between the physical environment and e-Science1 workflow systems, specifically through events processing systems, and provide a proof of concept implementation of that model in the context of the LEAD cyberinfrastructure. On the algorithmic side, we propose efficient stream mining algorithms that can be carried out on a continuous basis in real time over large volumes of observational data. 1 e-Science is used to describe computationally intensive science that is typically carried out in highly distributed network  相似文献   
112.
东北地区一次暴雪过程的诊断分析   总被引:1,自引:0,他引:1  
利用观测资料对东北地区的一次暴雪过程作了物理量场的诊断分析。分析结果表明:1.本次暴雪是受到贝加尔湖强冷空气和江淮暖湿气流的共同影响而形成的;2.稳定的地面形势和空中冷性长波槽的过境为本次暴雪过程提供了强大的动力条件;3.北上江淮暖湿气流携带来自东海和渤海两个源地的充沛水汽到达东北地区,为东北暴雪的产生提供了水汽条件;4.高低空垂直切变明显、高层辐散与低层辐合相配置导致的强上升运动以及中低层深厚的正涡度产生和维持是东北暴雪形成的动力机制。  相似文献   
113.
1991年是青海省最热的年份之一,而且青海省各地降水量时空分布不均匀。本文分析了导致今年天气异常发生的主要原因。  相似文献   
114.
本文介绍美国天气电报业务在90年代的新发展;讨论了天气电报业务监视软件的设计方案;并叙述该软件设计中主要技术问题的处理方法。  相似文献   
115.
人工影响天气领域一直致力寻求一种经济有效且催化效果明显的过冷云催化剂,纳米催化剂是首选.具有与冰晶结构相近的纳米材料因其尺寸效应、体积效应和其他表面效应等特性,有望提高冰晶晶核数量,有可能提高人工增雨的作业效果和作业能力,使寻求高效、价廉的人工影响天气催化剂成为了可能.作者主要针对纳米材料的性质和特点,通过理论分析和初步的实验,探讨了纳米催化剂在人工影响天气中的应用前景.  相似文献   
116.
大同地区暴雨的天气分型及其成因的初步分析研究   总被引:2,自引:0,他引:2       下载免费PDF全文
根据大同市所辖8个县气象站点自有气象记录以来的暴雨资料,应用天气学及气候学等原理,对大同地区暴雨的天气气候特征和形成机制进行了系统的分析与研究,得出了相关结论。  相似文献   
117.
The main objective of the present paper is to show a methodology for undertaking rainfall regionalization of a region taking into account the convective features of the precipitation, and useful for establishing homogeneous zones for improving the alert system. This methodology has been applied to a hydrographic region located in northeast Spain, with an area of 16000 km2 and characterized by a highly contrasted topography. Information provided by meteorological radar and 5-min precipitation data for 126 automatic raingauges has been used for the period 1996–2002. The previous analysis done on the basis of the 1927–1981 rainfall rate series for the Jardí raingauge, located in Barcelona, has also been considered. To that end, the first step was to draw up a proposal for classification of the pluviometric episodes. Recourse was had for this purpose to definition of the β parameter, related with the greater or lesser convective character of the event and calculated on the basis of the rainfall intensity at the surface (Llasat, 2001) and, when data are available, on the basis of radar reflectivity. Results show that the threshold of 35 mm/h to characterize convective episodes from raingauge data can be corroborated from the radar point of view when convective precipitation is identified using 2-D algorithms with a reflectivity threshold of 43 dBZ. Once the soundness of the β parameter had been corroborated, it was applied to more than 2900 precipitation episodes recorded in the region, in order to discriminate the features of the different subregions and their time and space distribution throughout the entire series of the samples. Using this definition, 92% of the precipitation events recorded in this region, with accumulated rainfall above 35 mm, are classified as convective ones, representing 95% of the precipitation amount. Application of the β parameter combined with monthly rainfall data allows differentiation of 8 regions with different convective precipitation features.  相似文献   
118.
本文分析了晋城市人工影响天气工作的现状,通过与先进地(市)比较,指出了存在的问题,并提出了以下对策:加强人工影响天气工作的领导和科学体系的建设;适应社会发展,拓宽服务领域;加强沟通协调,彻底解决空域申请难的问题;加大科研开发力度,加强人工影响天气队伍建设。  相似文献   
119.
利用2006—2015年京津冀气象站的常规观测资料和同期NCEP/NCAR再分析资料,以秋冬季影响雾霾形成与消散的静稳大气和通透大气为研究对象,统计分析了气象因子的分布状况。结果表明:京津冀秋冬季降水对雾霾起不到冲刷作用,反而促进雾霾的形成与维持;京津冀秋冬季雾霾消散主要是风场因子的贡献。雾霾消散的大气状态可分为3种类型,在不同大气状态下,各风场因子对雾霾消散的贡献不同。采用迭代自组织数据类差最大值阈值分割法找出了各风场因子的最佳阈值。根据各风场因子对雾霾消散的敏感性和因子间的相关,筛选出3类大气状态下雾霾消散因子指标。采用指标叠套法对2016、2017年秋冬季大气进行检验,表明雾霾消散指标及其阈值能较好区分静稳大气和通透大气,对雾霾过程具有较好的指示意义;通过对derf2.0模式产品释用,可为延伸期雾霾过程客观化预测提供技术支撑。  相似文献   
120.
Mountain range specific analog weather forecast model is developed utilizing surface weather observations of reference stations in each mountain range in northwest Himalaya (NW-Himalaya). The model searches past similar cases from historical dataset of reference observatory in each mountain range based on current situation. The searched past similar cases of each mountain range are used to draw weather forecast for that mountain range in operational weather forecasting mode, three days in advance. The developed analog weather forecast model is tested with the independent dataset of more than 717 days (542 days for Pir Panjal range in HP) of the past 4 winters (2003–2004 to 2006–2007). Independent test results are reasonably good and suggest that there is some possibility of forecasting weather in operational weather forecasting mode employing analog method over different mountain ranges in NW-Himalaya. Significant difference in overall accuracy of the model is found for prediction of snow day and no-snow day over different mountain ranges, when weather is predicted under snow day and no-snow day weather forecast categories respectively. In the same mountain range, significant difference is also found in overall accuracy of the model for prediction of snow day and no-snow day for different areas. This can be attributed to their geographical position and topographical differences. The analog weather forecast model performs better than persistence and climatological forecast for day-1 predictions for all the mountain ranges except Karakoram range in NW-Himalaya. The developed analog weather forecast model may help as a guidance tool for forecasting weather in operational weather forecasting mode in different mountain ranges in NW-Himalaya.  相似文献   
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