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81.
Storm surges pose significant danger and havoc to the coastal residents' safety, property, and lives, particularly at offshore locations with shallow water levels. Predictions of storm surges with hours of warning time are important for evacuation measures in low-lying regions and coastal management plans. In addition to experienced predictions and numerical models, artificial intelligence (AI) techniques are also being used widely for short-term storm surge prediction owing to their merits in good level of prediction accuracy and rapid computations. Convolutional neural network (CNN) and long short-term memory (LSTM) are two of the most important models among AI techniques. However, they have been scarcely utilised for surge level (SL) forecasting, and combinations of the two models are even rarer. This study applied CNN and LSTM both individually and in combination towards multi-step ahead short-term storm surge level prediction using observed SL and wind information. The architectures of the CNN, LSTM, and two sequential techniques of combining the models (LSTM–CNN and CNN–LSTM) were constructed via a trial-and-error approach and knowledge obtained from previous studies. As a case study, 11 a of hourly observed SL and wind data of the Xiuying Station, Hainan Province, China, were organised as inputs for training to verify the feasibility and superiority of the proposed models. The results show that CNN and LSTM had evident advantages over support vector regression (SVR) and multilayer perceptron (MLP), and the combined models outperformed the individual models (CNN and LSTM), mostly by 4%–6%. However, on comparing the model computed predictions during two severe typhoons that resulted in extreme storm surges, the accuracy was found to improve by over 10% at all forecasting steps.  相似文献   
82.
利用实测资料对比和FVCOM数值模拟等方法,研究了"利奇马"台风风暴潮在渤海的演变规律。研究表明:渤海沿岸的风暴潮过程是由局地风"直接作用"及外部天气系统"间接影响"共同作用引起的,且它们引起的风暴潮时空分布明显不同。在"利奇马"台风风暴潮中,"直接作用"引起的风暴增水在渤海湾和莱州湾沿岸分别约占总风暴增水的2/3和1/2。  相似文献   
83.
因台风风暴潮的突发性、情景演变时间的连续性和路径的不确定性,导致应急决策者在应急救援中难以做出正确决策,针对这一现状,将“情景—应对”应用在台风风暴潮应急决策中。本文在分析台风风暴潮情景、情景要素的概念模型基础上,首先通过资料搜集、属性识别等方法提取关键情景要素,采用框架表示法构建情景;然后分析台风风暴潮情景演变规律及演变路径;其次通过动态贝叶斯网络法构建台风风暴潮动态情景网络;最后利用先验概率与条件概率计算情景状态概率,实现了台风风暴潮的关键情景推演。本文以2018年9月16日11时至17时山竹台风对广东省沿海城市影响为例,演示了台风风暴潮的情景推演流程及关键技术。实证分析结果表明,溃堤、海水倒灌、洪水、滑坡发生的概率分别为85%、81%、74%、54%,验证了情景推演在风暴潮中应用的合理性。  相似文献   
84.
利用三维普林斯顿海洋模型(POM)以及逐时水位观测数据,研究印度洋北部斯里兰卡北部海岸风暴潮-潮汐相互作用特征.选择了2008年的"Nisha"台风作为台风风暴潮个例进行研究,并进行了3个数值敏感性试验.经验证,该风暴潮模型可以很好地再现该台风期间研究区域内的潮汐和总海水水位.试验结果表明,沿斯里兰卡西北海岸的风暴潮-潮汐相互作用显著,其强度与台风的强度和轨迹相关.当TC在42 h达到较大强度时,可以得到风暴潮-潮汐相互作用导致的最大增水值TSI (0.6 m)和从印度洋外海向斯里兰卡西北部浅滩流入的最大相互作用流场.在TC强度较弱的第30小时,得到最大负TSI (-0.6 m)和向南流出西北部浅水区域的较弱的相互作用流场.在整个台风期间,强TSI都发生在斯里兰卡西北部海滩到对岸的印度洋近岸区域.  相似文献   
85.
In this study,a coupled tide-surge-wave model was developed and applied to the South Yellow Sea.The coupled model simulated the evolution of storm surges and waves caused by extreme weather events,such as tropical cyclones,cold waves,extratropical cyclones coupled with a cold wave,and tropical cyclones coupled with a cold wave.The modeled surge level and significant wave height matched the measured data well.Simulation results of the typhoon with different intensities revealed that the radius to the maximum wind speed of a typhoon with 1.5 times wind speed decreased,and its influence range was farther away from the Jiangsu coastal region;moreover,the impact on surge levels was weakened.Thereafter,eight hypothetical typhoons based on Typhoon Chan-hom were designed to investigate the effects of varying typhoon tracks on the extreme value and spatial distribution of storm surges in the offshore area of Jiangsu Province.The typhoon along path 2 mainly affected the Rudong coast,and the topography of the Rudong coast was conducive to the increase in surge level.Therefore,the typhoon along path 2 induced the largest surge level,which reached up to 2.91 m in the radial sand ridge area.The maximum surge levels in the Haizhou Bay area and the middle straight coastline area reached up to 2.37 and 2.08 m,respectively.In terms of typhoons active in offshore areas,the radial sand ridge area was most likely to be threatened by typhoon-induced storm surges.  相似文献   
86.
Extreme water levels are related to astronomical tides and storm surges.Eleven typhoon systems,which have caused extreme water level rises,were selected based on 60-yr water level data from the Xiamen tide gauge station.In these 11 typhoon systems,the astronomical tide component accounts for 71%-95%of the total water level.The Gumbel distribution of extreme water level rise was estimated,and the impact of typhoon surges on water levels during the return period was analyzed.The ex-treme tide levels caused by typhoons Herb(1996)and Dujuan(2015)are much higher than those of other typhoons and correspond to the return period of 76 yr and 71 yr,respectively.The differences of sea levels in the presence and absence of these two typhoons in the 10-100 yr return period are 5.8-11.1 cm.For the 100-yr return period,the total risks within 10,25,50,and 100 yr increase by 94.3%,85.4%,72.9%,and 54.4%,respectively,if the Herb and Dujuan are not considered.Assuming that typhoon Herb(1996)occurred during the highest astronomical tide,it will produce a water level higher than that of the 1000-yr return period.Sea level rise has an important influence on the water level return period,and the contribution of nonlinear sea level rise in the next 100 yr is estimated to be 10.34%.  相似文献   
87.
青岛近海台风暴潮灾害分析   总被引:3,自引:0,他引:3  
分析了青岛沿海地区的台风暴潮灾害状况,阐明了潮灾成因,明确指出风暴潮在沿海自然灾害中占有重要的地位。  相似文献   
88.
江毓武  吴培木 《台湾海峡》1999,18(4):432-436
在台风风暴增水过程中,风应力占主要作用,气压项的作用要上对较小,许多风暴潮预报模式中气压项被忽略。本文在建立台湾海峡风暴潮预报模型的基础上峄台风气压项作用进行了模拟,结果发现在台湾海峡狭长的海域内,台风气压项的作用表现得较为特殊,在台风风暴潮模拟过程中,应考虑其贡献及大小。  相似文献   
89.
太湖和大浦河口风成流、风涌水的数值模拟及其单站验证   总被引:11,自引:5,他引:6  
介绍了太湖风成流和风涌水的数值摸拟工作。使用两种不同水平分辨率的数值模式,利用中日合作研究组在大浦河口实测的水位、湖流和风的资料对模拟结果进行了验证。结果指出,模式对风涌水及流向有较好的预报能力,流速的预报尚待进一步改进。  相似文献   
90.
本文根据影响湛江的典型热带气旋和风暴潮增水资料,系统地分析了热带气旋登陆地点、路径等要素和湛江港增水的关系。结果表明,湛江港发生的增水极值时间和增水形式因热带气旋登陆地点和路径的不同而异。从动力学进一步分析也表明,湛江港的增水类型与热带气旋登陆地点和路径关系非常密切。本文最后还讨论共振现象对湛江港增水的影响。  相似文献   
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