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Sediment movement characteristics of coast and analysis of seabed evolution

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Acta Oceanologica Sinica 2011年第5期30卷 101-107页

作者： KONG Lingshuang CAO Zude WANG Wei qi dingman Shanghai Estuary and Coastal Science Research Center Shanghai 201201 China Tianjin Research Institute for Water Transport Engineering Ministry of Transport Tianjin 300456 China

The rotary ring flume is used to study the silty sand movement in a periodic alternating *** of sediment movement of different coasts in the tidal current are *** detailed analysis of erosion-sedimentation function in a numerical simulation is *** equilibrium sediment concentration is *** on the equilibrium sediment concentration,the seabed erosion-sedimentation index is derived and the seabed erosion-sedimentation calculation is *** seabed erosion-sedimentation index is used to calculate the seabed evolution of Yangshan sea area and a good agreement with field measurements is obtained.

关键词： sediment movement periodic alternating current sediment numerical simulation equilibrium sediment concentration seabed erosion-sedimentation index

Study on roughness coefficient for unsubmerged reed in the Changjiang Estuary

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Acta Oceanologica Sinica 2011年第5期30卷 108-113页

作者： GU Fengfeng MU Lin qi dingman LI Junhua KONG Lingshuang WAN Yuanyang Shanghai Estuary and Coastal Science Research Center Shanghai 201201 China National Marine Data and Information Service State Oceanic Administration Tianjin 300171 China College of Ocean Environment and Engineering Shanghai Maritime University Shanghai 200135 China

The influence of density,foliage and stem flexibility on the roughness coefficients under unsubmerged conditions,such as Manning＇s n,is investigated *** instrumentation system has been developed for measuring the flow rate ranging from 0.1 to 0.3 L/s under the condition of different artificial foliated *** on the experimental results,the influence on the relationship between n with different density,foliage,flexibility and flow depth is *** is found that the foliage and the density are the important factors affecting Manning＇s *** a range of relatively low velocity and relatively large bending stiffness of stem,Manning＇s n is not influenced significanthy by the flexibility of stem.

关键词： Manning's coefficient foliage density flexibility reed

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小波在瞬态空化噪声分析中的应用

振动与冲击 2001年第1期20卷 82-84,30页

作者：戚定满沈焕庭华东师范大学河口海岸国家重点实验室上海200062

本文采用小波变换对于空泡溃灭过程中辐射的瞬态噪声进行了分析 ,得到对应的小波系数随时间和频率的变化图象。与传统的Fourier谱相比 ,小波系数图象能描述出噪声谱中各种频率成分随时间的变化 ,更准确地反映出瞬态空化噪声的时域特征。

关键词：小波分析瞬态空化噪声空泡溃灭时域特征

基于泥沙随机交换过程及不同推移形式的推移质输沙公式

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应用基础与工程科学学报 2023年第3期31卷 599-610页

作者：沈淇顾峰峰万远扬戚定满同济大学土木工程学院水利工程系上海200092 上海河口海岸科学研究中心上海201201

针对推移质输沙率公式难以兼顾高、低输沙强度计算的不足,提出结构上考虑推移质泥沙滑移及跃移特征的输沙率计算公式.基于无后效Markov随机理论,通过改进泥沙状态转化概率矩阵,优化了泥沙随机交换过程的描述.综合考虑床面遮蔽、水流脉... 详细信息

针对推移质输沙率公式难以兼顾高、低输沙强度计算的不足,提出结构上考虑推移质泥沙滑移及跃移特征的输沙率计算公式.基于无后效Markov随机理论,通过改进泥沙状态转化概率矩阵,优化了泥沙随机交换过程的描述.综合考虑床面遮蔽、水流脉动特征及床面泥沙运动特征的影响,从理论受力分析及概率统计角度,确定了床面推移质泥沙数量.通过引入推移质泥沙滑动、跃移平均运动速度,建立基于泥沙随机交换过程及不同推移形式的推移质输沙公式.最终计算结果与不同输沙强度下的试验及现场实测结果吻合较好,表明公式能兼顾高、低推移质输沙强度的计算,可应用于工程分析.

关键词：推移质输沙率泥沙交换 Markov过程滑移跃移概率统计分析

长江口深水航道三期工程后北槽洪枯季水沙运动特征研究

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海洋学报 2014年第7期36卷 118-124页

作者：沈淇高钦钦顾峰峰戚定满上海河口海岸科学研究中心交通部河口海岸重点实验室上海201201 上海市水利工程设计研究院有限公司上海200062

利用长江口深水航道三期整治工程前后,北槽洪枯季各测点水沙资料初步探讨了北槽洪枯季水沙运动特征。研究结果表明,北槽洪枯季潮周期平均含沙量分布自上而下总体呈"低-高-低"的分布态势,中段含沙量较高。洪季北槽各测点潮周期平均含沙... 详细信息

利用长江口深水航道三期整治工程前后,北槽洪枯季各测点水沙资料初步探讨了北槽洪枯季水沙运动特征。研究结果表明,北槽洪枯季潮周期平均含沙量分布自上而下总体呈"低-高-低"的分布态势,中段含沙量较高。洪季北槽各测点潮周期平均含沙量与潮周期平均流速相关性较差,北槽泥沙输运以平流输移为主。枯季两者相关较好,北槽泥沙运动则以起悬输运为主。北槽悬沙输运主要以欧拉输运为主,洪季北槽悬沙净输运率要明显大于枯季。洪季北槽中段潮泵及垂向环流作用最为明显,枯季,除北槽上段外,潮泵及垂向环流作用较小,水沙输运方向较为相近。造成洪季北槽中段潮泵作用及垂向环流输沙较大的原因是由于北槽中段滩槽泥沙交换频繁,涨潮流经南槽拦门沙及九段沙滩面后,挟带一定高含沙水体进入北槽,进而造成北槽中段潮泵及垂向环流输沙明显。

关键词：泥沙输运含沙量北槽机制分析

Friction between Strongly Compressed Polymer Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1368-1374,I0008页

作者： qi Liao Institute of Chemistry Chinese Academy of SciencesBejing 100190China

We present the results of molecular dynamics simulations of steady shear between a pair of neutral polymer brushes,as well as a pair of charged polymer brushes in the strongly compressed *** results of the molecular dynamic simulations of neutral and polyelectrolyte brushes in implicit solvent including normal forces,shear forces,viscosities and friction coefficients as a function of separation between brushes,are presented in the *** comparison of the simulation results of neutral and charged brushes shows that the charged brushes is in the quasi-neutral regime,and the dependence of viscosity on the separation distance show the similar power law of neutral *** simulation results confirm that the implicit solvent simulations of polyelectrolyte brushes that ignore hydrodynamics interaction are in agreement with the scaling predictions qualitatively because of screening of hydrodynamic interaction and long-range electrostatic interactions on the correlation length *** of neutral and charged brushes show the lubrication properties that the friction coefficient decreases with the separation decreases at enough large ***,a maximum of friction coefficients is observed for polyelectrolyte brushes,which is in contrast to the neutral brushes with monotonical dependence.

关键词： Polymer brush Frictions coefficient Polyelectrolyte Lubrication

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空化噪声谱特性研究

振动与冲击 1999年第3期18卷 32-36页

作者：戚定满鲁传敬何友声上海交通大学工程力学系上海200030

空化发生时，气泡经历成长、溃灭、反弹、再溃灭等复杂过程，辐射出尖的声压脉冲，对空泡辐射的噪声特性起主导作用。空泡一次溃灭辐射的脉冲可以用单指数函数或双指数函数来描述，空泡多次溃灭辐射的脉冲可以用振幅衰减的指数函数序列... 详细信息

空化发生时，气泡经历成长、溃灭、反弹、再溃灭等复杂过程，辐射出尖的声压脉冲，对空泡辐射的噪声特性起主导作用。空泡一次溃灭辐射的脉冲可以用单指数函数或双指数函数来描述，空泡多次溃灭辐射的脉冲可以用振幅衰减的指数函数序列来描述，本文对这些指数模型进行了详细的分析，得到不同模型对应的噪声谱。指出了这些模型的适用范围。并对经典单空泡噪声谱的特征进行了解释和说明。

关键词：空泡噪声空化指数脉冲噪声谱

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： Yong qi Shufen Zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic *** can produce one or more temporary shapes through nanoscale deformation,memorizing current *** can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural *** porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and ***,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and *** primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface *** aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of ***,perspectives on future research directions and applications are also *** is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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Science China(Technological Sciences) 2024年第5期67卷 1510-1523页

作者： WU ChengXing qi qi CHEN BaiJin YANG JiXiang DING Han State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height