检索结果-南通市图书馆

Frontogenesis and Frontolysis of a Cold Filament Driven by the Cross-Filament Wind and Wave Fields Simulated by a Large Eddy Simulation

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第3期41卷 509-528页

作者： Guojing LI dongxiao WANG changming dong Jiayi PAN Yeqiang SHU Zhenqiu ZHANG State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Shool of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

The variations of the frontogenetic trend of a cold filament induced by the cross-filament wind and wave fields are studied by a non-hydrostatic large eddy simulation. Five cases with different strengths of wind and wave fields are *** results show that the intense wind and wave fields further break the symmetries of submesoscale flow fields and suppress the levels of filament frontogenesis. The changes of secondary circulation directions—that is, the conversion between the convergence and divergence of the surface cross-filament currents with the downwelling and upwelling jets in the filament center—are associated with the inertial oscillation. The filament frontogenesis and frontolysis caused by the changes of secondary circulation directions may periodically sharpen and smooth the gradient of submesoscale flow *** lifecycle of the cold filament may include multiple stages of filament frontogenesis and frontolysis.

关键词： cold filament frontogenesis frontolysis large eddy simulation

Study on the interannual variability of the Kerama Gap transport and its relation to the Kuroshio/Ryukyu Current system

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第3期43卷 1-14页

作者： Han Zhou Kai Yu Jianhuang Qin Xuhua Cheng Meixiang Chen changming dong Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210003China College of Oceanography Hohai UniversityNanjing 210003China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 211800China

An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryukyu Current *** study found a significant difference in the interannual variability of the upstream and downstream transports of the East China Sea-(ECS-)Kuroshio and the Ryukyu *** interannual variability of the KGT was found to be of paramount importance in causing the differences between the upstream and downstream ***,it contributed approximately 37%to the variability of the Ryukyu *** interannual variability of the KGT was well described by a two-layer rotating hydraulic *** was dominated by its subsurface-intensified flow core,and the upper layer transport made a weaker negative contribution to the total *** subsurface flow core was found to be mainly driven by the subsurface pressure head across the Kerama Gap,and the pressure head was further dominated by the subsurface density anomalies on the Pacific *** density anomalies could be traced back to the eastern open ocean,and their propagation speed was estimated to be about 7.4 km/d,which is consistent with the speed of the local first-order baroclinic Rossby *** the negative(positive)density anomaly signal reached the southern region of the Kerama Gap,it triggered the increase(decrease)of the KGT towards the Pacific side and the formation of an anticyclonic(cyclonic)vortex by baroclinic ***,there is an increase(decrease)in the upstream transport of the entire Kuroshio/Ryukyu Current system and an offshore flow that decreases(increases)the downstream Ryukyu Current.

关键词： Kerama Gap Kuroshio Ryukyu Current OGCM for the Earth Simulator(OFES) hydraulic theory

Rotating tank experiments for the study of geophysical fluid dynamics

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第5期42卷 1385-1398页

作者： changming dong Xiaojie LU Yuli LIU Guoqing HAN Minghan FU Qian CAO Yang ZHANG Xu CHEN Yeping YUAN International Geophysical Fluid Dynamics Laboratory Nanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric and Oceanic Sciences University of CaliforniaLos Angeles CA 90095USA State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Zhejiang Ocean University Zhoushan 316022China Guangdong Ocean University Zhanjiang 524088China Ocean University of China Qingdao 266100China Zhejiang University Hangzhou 310058China

Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural *** a wide range of applications such as weather forecasts and climate prediction,GFD employs various research approaches including in-situ observations,satellite measurements,numerical simulations,theoretical analysis,artificial intelligence,and physical model experiments in *** these approaches,rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in *** proportional scaling and proper techniques,scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system,which allows for the simulation of essential characteristics of fluid motions in the atmosphere and *** this review,rotating tanks of various scales in the world are introduced,as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere *** illustrate the GFD experiments,three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments:mesoscale eddies in the ocean,convection processes,and plume *** references for the experimental procedures are *** studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research *** is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes.

关键词： laboratory experiment rotating tank geophysical fluid dynamics(GFD)

全氟乙烯基醚类单体的自由基共聚合、基于“SuFEx”点击反应的后修饰及其性能

在线全文

学校读者我要写书评

暂无评论

功能高分子学报 2024年第3期37卷 205-214页

作者：葛玮宋莹莹魏刚董常明上海交通大学化学化工学院上海市电气绝缘与热老化重点实验室上海200240 山东东岳未来氢能材料股份有限公司含氟功能膜材料国家重点实验室山东淄博256401

首先在常压和非氟溶剂中通过自由基热引发共聚合制备了6种全氟乙烯基醚类单体与非氟乙烯基醚类单体的共聚物,然后经“SuFEx”点击反应进行功能化修饰制得聚合物分子刷,进一步通过透析法构筑高含氟量的聚合物纳米粒子。利用傅里叶变换红... 详细信息

首先在常压和非氟溶剂中通过自由基热引发共聚合制备了6种全氟乙烯基醚类单体与非氟乙烯基醚类单体的共聚物,然后经“SuFEx”点击反应进行功能化修饰制得聚合物分子刷,进一步通过透析法构筑高含氟量的聚合物纳米粒子。利用傅里叶变换红外光谱(FT-IR)、核磁共振氟谱(^(19)F-NMR)、核磁共振氢谱(^(1)H-NMR)差示扫描量热分析(DSC)和凝胶渗透色谱(GPC)等详细表征了含氟聚合物的结构、接枝率及物化性能,证明全氟乙烯基醚类单体与非氟乙烯基醚类单体共聚合得到交替共聚物,与乙酸乙烯酯单体共聚合得到无规共聚物。同时“SuFEx”点击反应可以实现磺酰氟(―SO_(2)F)共聚物侧链的高效接枝。紫外-可见分光光度计(UV-Vis)、动态光散射(DLS)和透射电镜(TEM)分析表明,两亲性氟化共聚物自组装形成了流体力学粒径120 nm左右的球形胶束状聚集体,且具有较低的临界聚集浓度。

关键词：全氟乙烯基醚氟化共聚物 SuFEx点击反应氟化聚合物刷纳米粒子

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

孟加拉湾南部冷池的极端事件及其机理初析

应用海洋学学报 2024年第1期43卷 12-19页

作者：冯建杰潘爱军董昌明林新宇邱云自然资源部第三海洋研究所福建厦门361005 南京信息工程大学海洋科学学院江苏南京210044 南方海洋科学与工程广东省实验室(珠海) 广东珠海519082

本研究利用多源卫星遥感数据对比分析了2018年和2015年孟加拉湾南部冷池的极端异常事件。孟加拉湾南部冷池早期出现在5月,8月和9月强度达到最大,10月开始减弱,随后逐渐消失。数据显示2018年和2015年冷池海表温度距平值分别为-0.55℃和0... 详细信息

本研究利用多源卫星遥感数据对比分析了2018年和2015年孟加拉湾南部冷池的极端异常事件。孟加拉湾南部冷池早期出现在5月,8月和9月强度达到最大,10月开始减弱,随后逐渐消失。数据显示2018年和2015年冷池海表温度距平值分别为-0.55℃和0.43℃,是1993—2018年26年中冷池降温最强和最弱的年份。2018年孟加拉湾南部冷池风应力距平值为0.02 N/m2,而2015年距平值为-0.01 N/m2。2018年Ekman抽吸速度距平在冷池区域为正,2015年为负。经混合层热收支计算得到,造成冷池产生的主要原因是平流效应,且2018年与2015年的夏季(6—8月)降温平流项分别占49.2%和80.7%。冷池极端事件主要发生在6月,2018年6月冷池降温是2015年的2.76倍,并且海表净热通量项和平流项的异常对冷池极端事件的产生起了重要作用。

关键词：海洋水文学冷池西南季风流混合层热收支孟加拉湾

在线全文

学校读者我要写书评

暂无评论

基于STL的南海海表温度组合预测模型

海洋环境科学 2024年第1期43卷 109-118页

作者：杨乐晴王丽娜张红春董昌明南京信息工程大学人工智能学院(未来技术学院) 江苏南京210044 南方海洋科学与工程广东省实验室(珠海) 广东珠海519080 南京信息工程大学海洋科学学院江苏南京210044

海表温度(sea surface temperature,SST)是海洋科学研究的重要内容之一。SST的异常波动导致海洋灾害、气象灾害现象时有发生,SST的精确预测对海洋环境保护和海洋经济发展有重要意义。针对SST序列的季节性、非平稳性,首先利用周期趋势分... 详细信息

海表温度(sea surface temperature,SST)是海洋科学研究的重要内容之一。SST的异常波动导致海洋灾害、气象灾害现象时有发生,SST的精确预测对海洋环境保护和海洋经济发展有重要意义。针对SST序列的季节性、非平稳性,首先利用周期趋势分解算法(seasonal-trend decomposition procedure based on loess, STL)对数据进行预处理,分解得到季节分量、趋势分量和残差分量子序列,依次选择相应的预测方法构建组合模型。季节分量应用具有时间嵌入编码模块的Transformer网络预测,充分挖掘序列全局信息,解决时间序列长时间依赖问题;趋势分量应用线性回归模型预测;残差分量应用自回归模型预测。选取南海海域单点SST数据,应用基于STL的SST组合预测模型建模,预测5 d的SST值。实验结果表明,本文模型在单点SST预测任务中,能够有效捕获SST变化规律,提高预测精度。

关键词：海表温度周期趋势分解 Transformer 线性回归 AR模型

基于CNN-STLSTM-CNN模型的有效波高预测

在线全文

学校读者我要写书评

暂无评论

海洋环境科学 2024年第3期43卷 417-429页

作者：王丽娜齐致远张红春董昌明南京信息工程大学人工智能学院(未来技术学院) 江苏南京210044 南方海洋科学与工程广东省实验室(珠海) 广东珠海519080 南京信息工程大学长望学院江苏南京210044 南京信息工程大学海洋科学学院江苏南京210044

有效波高(significant wave height,SWH)是海洋的重要参数之一,对其的精确预测对渔业发展、海上交通和海洋生态系统具有重要意义。为了提高有效波高的预测精度,本文提出了一种基于卷积神经网络-时空长短时记忆神经网络-卷积神经网络(con... 详细信息

有效波高(significant wave height,SWH)是海洋的重要参数之一,对其的精确预测对渔业发展、海上交通和海洋生态系统具有重要意义。为了提高有效波高的预测精度,本文提出了一种基于卷积神经网络-时空长短时记忆神经网络-卷积神经网络(convolutional neural network-spatiotemporal long short-term memory-convolutional neural network,CNN-STLSTM-CNN)的有效波高预测模型。该模型由编码器(Encoder)、解释器(Translator)和解码器(Decoder)构成。Encoder通过卷积神经网络提取SWH数据的空间特征,Translator通过时空长短时记忆神经网络(spatiotemporallongshort-term memory,STLSTM)提取SWH数据的空间特征在时间上的变化特性,Decoder通过卷积神经网络的转置卷积模块重建预测结果。对东海和南海海域的二维有效波高数据进行建模,实验结果表明CNNSTLSTM-CNN模型的均方根误差(root mean squared error,RMSE)、平均绝对误差(mean absolute error,MAE)、均方根误差均值(mean of root mean squared error,M_RMSE)和平均绝对误差均值(mean of mean absolute error,M_MAE)等指标值均低于已有的方法,验证了CNN-STLSTM-CNN模型的有效性。

关键词：有效波高卷积神经网络时空长短时记忆神经网络转置卷积

在线全文

学校读者我要写书评

暂无评论

融合IVMD的海表温度时空智能预测方法

海洋测绘 2024年第3期44卷 53-57,61页

作者：韩莹曹允重张凌珺赵芮晗董昌明江苏省大气环境与装备技术协同创新中心江苏南京210044 南京信息工程大学自动化学院江苏南京210044 南方海洋科学与工程广东省实验室(珠海) 广东珠海519000 南京信息工程大学海洋科学学院江苏南京210044

精准的海洋表面温度(sea surface temperature, SST)预测在海洋和气象领域具有重要意义,如海洋渔业捕捞和海洋天气预报等。提出一种融合改进变分模态分解(improved variational mode decomposition, IVMD)的时空混合模型来预测SST,采用... 详细信息

精准的海洋表面温度(sea surface temperature, SST)预测在海洋和气象领域具有重要意义,如海洋渔业捕捞和海洋天气预报等。提出一种融合改进变分模态分解(improved variational mode decomposition, IVMD)的时空混合模型来预测SST,采用中心频率观察法、残差指数最小化和皮尔逊相关系数改进变分模态分解(variational mode decomposition, VMD),去除SST序列冗余,利用图卷积神经网络(graph convolutional network, GCN)提取SST交互特征并结合长短时记忆网络(long short-term memory, LSTM)捕捉时间动态,提高预测精度。选取中国东海海域进行实证分析,实验结果表明:与现有模型对比,本文模型在均方根误差、平均绝对误差和平均绝对百分比误差3个指标上均有显著提升,验证了本文模型的有效性和稳定性。

关键词：海洋表面温度预测改进变分模态分解皮尔逊相关系数图卷积神经网络长短时记忆网络

Statistical analysis of intensity variations in tropical cyclones in the East China Sea passing over the Kuroshio

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2020年第6期38卷 1632-1639页

作者： YU Yang dong changming SHAN Haixia ZOU Bin College of Marine Sciences Nanjing University of Information Science&TechnologyNanjing 210044China National Satellite Ocean Application Service Ministry of Natural ResourcesBeijing 100080China Southern Laboratory of Ocean Science and Engineering Zhuhai 519000China

Intensity variations of the SE-NW-oriented tropical cyclones(TC)in the East China Sea(ECS)passing over the Kuroshio are studied using multi-year high-resolution sea surface temperature data,the tropical cyclone data,and the global reanalysis *** statistical results show that there are 81 TCs passing over the Kuroshio from the southeast in the East China Sea,over 68 years from 1949 to *** terms of the change of the atmospheric pressure in the center of the TC,there are three categories:31 TCs are intensified,28 maintain their intensities,and 22 *** seasonal differences are presented in the *** the analysis on the intensified TCs,it is found that the TCs in the range where the center translational speed is from 1 m/s to 8 m/s and the distance from the Kuroshio main axis is from 10 km to 75 km are intensified more *** analysis of three specific examples of TCs show that the stronger characteristics of the Kuroshio warm water in the ECS,the greater the intensity increase of such tropical cyclones.

关键词： intensity of typhoons Kuroshio East China Sea