检索结果-南通市图书馆

A process-based model for sediment transport under various wave and current conditions

International Journal of Sediment research 2011年第4期26卷 498-512页

作者： Chi ZHANG,Jin-Hai ZHENG,Yi-Gang WANG, Meng-Tao ZHANG,Dong-Sheng JENG,and Ji-Sheng ZHANG 1 Dr.,State Key Laboratory of Hydrology-water resources and Hydraulic engineering,Hohai University,1 Xikang Road,nanjing 2.0098,china, 2 Prof,Corresponding author,State Key Laboratory of Hydrology-water resources and Hydraulic engineering, Hohai University,1 Xikang Road,nanjing 2.0098,china, 3 Prof.,4 Bachelor,6 Assoc.Prof.,College of Harbor,Coastal and Offshore engineering,Hohai University,1 Xikang Road,nanjing 2.0098,china 5 Prof,center for Marine Geotechnical engineering research,Shanghai Jiao Tong University,Shanghai 200240, china Division of Civil engineering,University of Dundee,Dundee DD1 4HN,United Kingdom [a] Dr. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University 1 Xikang Road Nanjing 210098 China [b] Prof. Corresponding author State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University 1 Xikang Road Nanjing 210098 China [c] Prof. College of Harbor Coastal and Offshore Engineering Hohai University 1 Xikang Road Nanjing 210098 China [d] Bachelor College of Harbor Coastal and Offshore Engineering Hohai University 1 Xikang Road Nanjing 210098 China [e] Prof. Center for Marine Geotechnical Engineering Research Shanghai Jiao Tong University Shanghai 200240 China Division of Civil engineering University of Dundee Dundee DD1 4HN United Kingdom [f] Assoc. Prof. College of Harbor Coastal and Offshore Engineering Hohai University 1 Xikang Road Nanjing 210098 China

The purpose of this study is to investigate the capability of a newly developed process-based model for sediment transport under a wide variety of wave and current *** model is based on the first-order boundary layer equation and the sediment advection-diffusion *** particular,a modified low Reynolds number k-e model is coupled to provide the turbulence *** model verifications have been performed by simulating a number of laboratory experiments,covering a considerable range of hydrodynamic conditions such as sinusoidal waves,asymmetric waves and wave-current *** model provides satisfactory numerical results which agree well with the measured results,including the time-averaged/dependent sediment concentration profiles and sediment flux profiles,as well as the time series of concentration at given *** observed influences of wave orbital velocity amplitude,wave period and sediment grain size are correctly reproduced,indicating that the fundamental physical mechanisms of those processes are properly represented in the *** is revealed that the present model is capable of predicting sediment transport under a wide range of wave and current conditions,and can be used to further study the morphodynamic processes in real coastal regions.

关键词： Sediment transport Wave Current Numerical model

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Heavy-duty anticorrosive Zn-Al composite coatings for offshore steel structure

Heavy-duty anticorrosive Zn-Al composite coatings for offsho...

引用

2011中国材料研讨会

作者： Fumin Lu a,Aibin Ma a,b,Jinghua Jiang a,b,Liuyan Zhang a,Dan Song a,Donghui Yang a,Jianqing Chen a a College of Mechanics and Materials,Hohai University,nanjing 2.0098,china b national engineering research center of water resources efficient utilization and engineering safety,Hohai University,nanjing 2.0098,china

With aim to protect the steel tower part of wind power facility against marine corrosion,three kinds of heavy-duty anticorrosive composite coatings （CZ,CA and CZA） were *** a three-layer system,the composite coating consists of arc-sprayed metallic （Zn,Al or Zn-15mass%Al） coating （primer layer）,epoxy paint pigmented with micaceous iron oxide （intermediate layer） and acrylic polyurethane coating （surface layer）.The corrosion behaviors of single-layer arc-sprayed metallic coatings （SZ,SA and SZA） were investigated by potentiodynamic polarization tests,electrochemical impedance spectroscopy （EIS） analyses and SEM *** suit performance of composite coatings was evaluated by salt spray *** results indicated that the SZA coating behaved both good blocking effect like SA coating and good ability of cathodic protection like SZ ***,the CZA coating with excellent suit performance and good stability satisfied the request for long-term anti-corrosion for offshore steel structure.

关键词： electric arc spraying corrosion behavior composite coating suit performance durability

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

基于结构振动参数的损伤识别法

引用

水电能源科学 2009年第4期27卷 104-107页

作者：霍中艳张岚河海大学水利水电工程学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

综述了基于结构振动的损伤识别方法中较为常用和有效的方法,在前人研究基础上对其进行分类和评述,重点论述了基于曲率的损伤识别法的优缺点及其适用范围,并对基于结构振动参数的损伤识别法应用于水工结构等大型复杂结构中存在的问题进... 详细信息

综述了基于结构振动的损伤识别方法中较为常用和有效的方法,在前人研究基础上对其进行分类和评述,重点论述了基于曲率的损伤识别法的优缺点及其适用范围,并对基于结构振动参数的损伤识别法应用于水工结构等大型复杂结构中存在的问题进行了讨论,展望了未来发展方向和趋势。

关键词：损伤识别结构振动模态参数振型曲率

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Delayed Hopf bifurcation in time-delayed slow-fast systems

引用

Science china(Technological Sciences) 2010年第3期53卷 656-663页

作者： ZHENG YuanGuang1 & WANG ZaiHua1,2 1 Institute of Vibration engineering research,nanjing University of Aeronautics and Astronautics,nanjing 210016,china 2 Institute of Science,PLA University of Science and Technology,nanjing 211101,china 1. Institute of Vibration engineering research Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Institute of Science PLA University of Science and Technology Nanjing 211101 China

This paper presents an investigation on the phenomenon of delayed bifurcation in time-delayed slow-fast differential *** the two delayed's have different *** delayed bifurcation means that the bifurcation does not happen immediately at the bifurcation point as the bifurcation parameter passes through some bifurcation point,but at some other point which is above the bifurcation point by an obvious *** a time-delayed system,the evolution of the system depends not only on the present state but also on past *** this paper,the time-delayed slow-fast system is firstly simplified to a slow-fast system without time delay by means of the center manifold reduction,and then the so-called entry-exit function is defined to characterize the delayed bifurcation on the basis of Neishtadt's *** shows that delayed Hopf bifurcation exists in time-delayed slow-fast systems,and the theoretical prediction on the exit-point is in good agreement with the numerical calculation,as illustrated in the two illustrative examples.

关键词： time delay delayed bifurcation Hopf bifurcation slow-fast systems exit-point entry-exit function

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

大坝安全监控PCA-BP融合模型研究

引用

水电能源科学 2011年第2期29卷 47-49,34页

作者：刘红萍马文丽河海大学水利水电学院江苏南京210098 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对大坝资料分析中经常遇到多因子的相关性影响分析效果的问题,利用主成分分析法提取综合变量,与BP神经网络相融合构建了大坝安全监控PCA-BP融合模型,并与传统大坝安全监控模型做了对比分析。结果表明,模型优化拟合精度得到提高,收敛... 详细信息

针对大坝资料分析中经常遇到多因子的相关性影响分析效果的问题,利用主成分分析法提取综合变量,与BP神经网络相融合构建了大坝安全监控PCA-BP融合模型,并与传统大坝安全监控模型做了对比分析。结果表明,模型优化拟合精度得到提高,收敛时间加快。

关键词：大坝安全监控模型主成分分析 BP神经网络

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Large-eddy simulations and vortex structures of turbulent jets in crossflow

引用

Science china(Physics,Mechanics & Astronomy) 2007年第1期50卷 118-132页

作者： GUAN Hui1,2 & WU ChuiJie2 1 School of Mechanical and Power engineering,East china University of Science and Technology,Shanghai 200237,china 2 research center for Fluid Dynamics,PLA University of Science and Technology,nanjing 211101,china 1. School of Mechanical and Power engineering East China University of Science and Technology Shanghai 200237 China 2. research center for Fluid Dynamics PLA University of Science and Technology Nanjing 211101 China

Using the method of large-eddy simulation, the 3-dimensional turbulent jets in crossflow with stream-wise and transverse arrangements of nozzle are simulated, emphasizing on the dynamical process of generation and evolution of vortex structures in these flows. The results show that the basic vortex structures in literatures, such as the counter-rotating vortex pair, leading-edge vortices, lee-side vortices, hanging vortices, kidney vortices and anti-kidney vortices, are not independent physical substances, but local structures of the basic vortex structure of turbulent jets in crossflow-the 3-D stretching vortex rings originating from the orifice of the nozzle, which is discovered in this study. Therefore, the most important large-scale structures of turbulent jets in crossflow are unified to the 3-D vortex rings which stretch and twist in stream-wise and swing in transverse directions. We also found that the shedding frequencies of vortex rings are much lower than the one corresponding to the appearance of leading-edge and lee-side vortices in the turbulent jets.

关键词： turbulent jet in crossflow coherent structure large-eddy simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Molecular hosts for triplet emitters in organic light-emitting diodes and the corresponding working principle

引用

Science china Chemistry 2010年第8期53卷 1679-1694页

作者： MI BaoXiu1,2,GAO ZhiQiang1,LIAO ZhangJin2,HUANG Wei2 & CHEN Chin Hsin3 1Jiangsu engineering center for Flat-Panel Displays & Solid-State Lighting School of Materials Science & engineering,nanjing University of Posts & Telecommunications,nanjing 210046,china 2Key Laboratory for Organic Electronics & Information Displays (KLOEID),Institute of Advanced Materials (IAM),nanjing University of Posts & Telecommunications,nanjing 210046,china 3Display Institute,Microelectronics and Information Systems research center,national Chiao Tung University Hsinchu,Hsinchu,300 china 1. Jiangsu engineering center for Flat-Panel Displays & Solid-State Lighting School of Materials Science & engineering Nanjing University of Posts & Telecommunications Nanjing 210046 China2. Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing 210046 China3. Display Institute Microelectronics and Information Systems Research Center National Chiao Tung University Hsinchu Hsinchu 300 China

This paper summarizes the mechanism and routes for excitation of triplet emitters in dopant emission based phosphorescent organic light-emitting diodes (PhOLEDs),providing a comprehensive overview of recent progress in molecular hosts for triplet emitters in ***,based on the nature of different hosts,e.g.,hole transporting,electron transporting or bipolar materials,in which the dopant emitters can be hosted to generate phosphorescence,the respective device performances are summarized and *** are given to the relationships among the molecular structure,thermal stability,triplet energy,carrier mobility,molecular orbital energy level and their corresponding device performances.