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Impact of Wind on Tide-Induced Advective Salt Transport in A Well- Mixed Estuary

China Ocean Engineering 2021年第1期35卷 107-122页

作者： CHEN Wei-lun zhu yu-liang KONG Jun CHU Ao ZHANG Wei-sheng State Key Laboratory of Hydrology Water Resources and Hydraulic EngineeringHohai UniversityNanjing 210098China Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai UniversityNanjing 210098China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Key Laboratory of the Pearl River Estuarine Dynamics and Associated Process Regulation Ministry of Water ResourcesGuangzhou 510610China Faculty of Civil Engineering and Geosciences Section of Hydraulic EngineeringDelft University of Technology2600 GA DelftThe Netherlands

The tide-induced net advective salt flux in well-mixed estuaries consists of five terms according to the method from *** term resulted from the vertical variation in salinity can be negligible in well-mixed estuaries with four tide-induced salt flux terms,known as F1−*** explore the effects of wind on these salt fluxes,the current-salinity analytical model combined with the perturbation analysis is extended by including *** expressions for the four salt fluxes are derived separately in the present *** the assumption that only the M_(2) tidal component is accounted for and the salt flux generated by diffusion is not studied,the tide-induced net advective salt flux Q_(sx) is in the seaward direction without the wind *** applying the Western Scheldt estuary case,the wind influence on the tidal advection salt flux(TASF)distribution in the F4 term was *** phase difference between zero-order velocity and first-order salinity(Δφ)at the surface layer of the estuary is larger than 90°and smaller than 90°at the bottom layer,which leads to landward TASF in the surface layer and seaward TASF in the bottom *** distribution ofΔφis not uniform in the horizontal direction with wind included,which differs from the result without *** the case of seaward wind with the speed of 18 m/s,the decrease in the zeroth-order velocity phase(φu)at the surface layer is larger than that of the first-order salinity phase(φs)downstream,which leads to an abnormal seaward TASF in this *** to the surface stress caused by wind,the Stokes compensation flow in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is ***,the first-order velocity in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is also *** first-order salinity also increases/decreases with the increase of la

关键词： tide-induced net advective salt flux analytical expression wind effect well-mixed estuary Western Scheldt Estuary

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Batch image alignment via subspace recovery based on alternative sparsity pursuit

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Computational Visual Media 2017年第3期3卷 295-304页

作者： Xianhui Lin zhu liang yu Zhenghui Gu Jun Zhang Zhaoquan Cai College of Automation Science and Engineering South China University of Technology School of Information Engineering Guangdong University of Technology School of Computer Science Huizhou University

The problem of robust alignment of batches of images can be formulated as a low-rank matrix optimization problem, relying on the similarity of well-aligned images. Going further, observing that the images to be aligned are sampled from a union of low-rank subspaces, we propose a new method based on subspace recovery techniques to provide more robust and accurate alignment. The proposed method seeks a set of domain transformations which are applied to the unaligned images so that the resulting images are made as similar as possible. The resulting optimization problem can be linearized as a series of convex optimization problems which can be solved by alternative sparsity pursuit techniques. Compared to existing methods like robust alignment by sparse and low-rank models, the proposed method can more effectively solve the batch image alignment problem,and extract more similar structures from the misaligned images.

关键词： image alignment subspace recovery sparse representation convex optimization image similarity

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Sampling Surface Particle Size Distributions and Stability Analysis of Deep Channel in the Pearl River Estuary

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China Ocean Engineering 2017年第3期31卷 299-307页

作者： FENG Hao-chuan ZHANG Wei zhu yu-liang LEI Zhi-yi JI Xiao-mei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Particle size distributions （PSDs） of bottom sediments in a coastal zone are generally multimodal due to the complexity of the dynamic environment. In this paper, bottom sediments along the deep channel of the Pearl River Estuary （PRE） are used to understand the multimodal PSDs＇ characteristics and the corresponding depositional environment. The results of curve-fitting analysis indicate that the near-bottom sediments in the deep channel generally have a bimodal distribution with a fine component and a relatively coarse component. The particle size distribution of bimodal sediment samples can be expressed as the sum of two lognormal functions and the parameters for each component can be determined. At each station of the PRE, the fine component makes up less volume of the sediments and is relatively poorly sorted. The relatively coarse component, which is the major component of the sediments, is even more poorly sorted. The interrelations between the dynamics and particle size of the bottom sediment in the deep channel of the PRE have also been investigated by the field measurement and simulated data. The critical shear velocity and the shear velocity are calculated to study the stability of the deep channel. The results indicate that the critical shear velocity has a similar distribution over large part of the deep channel due to the similar particle size distribution of sediments. Based on a comparison between the critical shear velocities derived from sedimentary parameters and the shear velocities obtained by tidal currents, it is likely that the depositional area is mainly distributed in the northern part of the channel, while the southern part of the deep channel has to face higher erosion risk.

关键词： multimodality particle size distribution tidal currents potential erosion Pearl River Estuary

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THREE-DIMENSIONAL NUMERICAL MODELLING OF SUBMERGED DIKE ALIGNMENT IN CURVED ESTUARINE CHANNEL

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Journal of Hydrodynamics 2005年第5期17卷 601-606页

作者： ZHENG Jin-hai LIU Ying-qi YAN Yi-xin zhu yu-liang Research Institute of Coastal and Ocean Engineering Hohai University Nanjing 210098 China

Submerged dikes were frequently built in curved estuarine channels to improve navigational conditions. A three-dimensional numerical model of tidal motions was developed to simulate flows through the submerged dike alignment in curved estuarine reach of complex bathymetry on the basis of satisfactory calibrations. Through the analysis of the morphological characteristics of the curved channel of the Huangpu River mouth in the Yangtze River Delta, a submerged dike alignment project was examined. The effect of the navigation channel improvement project and its influence on the flow regimes, the navigational conditions, the flood control and the operating conditions of harbours within the adjacent water area were evaluated, and the technical feasibility of the navigation channel improvement scheme was demonstrated.

关键词： submerged dike alignment three-dimensional numerical model curved estuarine channel morphological analysis

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EXPERIMENTAL INVESTIGATION OF CHARACTERISTIC FREQUENCY IN UNSTEADY HYDRAULIC BEHAVIOUR OF A LARGE HYDRAULIC TURBINE

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Journal of Hydrodynamics 2009年第1期21卷 12-19页

作者： WANG Fu-jun LI Xiao-qin MA Jia-mei YANG Min zhu yu-liang College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China Beijing Huake Tongan Monitoring Technology Co. Ltd. Beijing 100037 China

The features of unsteady flow such as pressure variation and fluctuation in a large hydraulic turbine usually lead to the instability of operation. This article reports the recent in site investigation concerning the characteristic frequencies in pressure fluctuation, shaft torsional oscillation and structural vibration of a prototype 700 MW Francis turbine unit. The investigation was carried out for a wide load range of 200 MW-700 MW in the condition of water head 57 m-90 m. An extensive analysis of both time-history and frequency data of these unsteady hydraulic behaviours was conducted. It was observed that the pressure fluctuation in a draft tube is stronger than that in upstream flow passage. The low frequency with about one third of rotation frequency is dominative for the pressure fluctuation in part load range. Also the unsteady features of vibration of head cover and torsional oscillation of shaft exhibited the similar features. Numerical analysis showed that the vibration and oscillation are caused by vortex rope in the draft tube. In addition, a strong vibration with special characteristic frequency was observed for the head cover in middle load range. The pressure fluctuation in the draft tube with the same frequency was also recorded. Because this special vibration has appeared in the designed normal running condition, it should be avoided by carefully allocating power load in the future operation.

关键词： hydraulic turbine part load swirling flow unsteady behaviour characteristic frequency power load allocation

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珠江口盐水入侵预测模式研究

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水利学报 2013年第9期44卷 1009-1014页

作者：诸裕良闫晓璐林晓瑜河海大学港口海岸与近海工程学院江苏南京210098

随着珠江口地区经济的迅速发展，盐水入侵日益严晕，不仅影响到周边城市的淡水供应．也为工农业生产带来了不必要的损失。基于前人研究成果，推导了一种简单有效的盐水入侵预测模式。该预测模式首先通过对现有的水文资料做线性回归分析... 详细信息

随着珠江口地区经济的迅速发展，盐水入侵日益严晕，不仅影响到周边城市的淡水供应．也为工农业生产带来了不必要的损失。基于前人研究成果，推导了一种简单有效的盐水入侵预测模式。该预测模式首先通过对现有的水文资料做线性回归分析，反演出河道的扩散系数Dx，再将Dx代入预测模式，即可计算出河道沿程的盐度值和盐水入侵距离。为了检验该预测模式，利用磨刀门2005年1月19日至2月4日的水文实测资料，就磨刀门的盐水入侵情况进行模拟，并采用卡方拟合优度检验法分析预测误差，结果表明该盐水入侵预测模型在磨刀¨具有适用性。最后，通过分析磨刀门地区盐水入侵距离与潮差的响应关系，得出小潮前2～3d为增大压咸流量的最佳时机这一结论，可为“咸害”的防治提供理论依据。

关键词：盐水入侵预测模式磨刀门卡方拟合优度检验法

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宽度学习系统在蘑菇毒性判别中的应用

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现代食品科技 2019年第7期35卷 267-272,54页

作者：李旺俞祝良华南理工大学自动化科学与工程学院

为了提升蘑菇毒性判别的准确率,消除个体差异,本文提出了一种基于宽度学习系统的蘑菇毒性判别方法。文章首先对蘑菇各特征指标与其毒性判别的相关性进行了探究,其所得结果显示蘑菇的气味和颜色是其区分度最大的特征,该结果与人工判别积... 详细信息

为了提升蘑菇毒性判别的准确率,消除个体差异,本文提出了一种基于宽度学习系统的蘑菇毒性判别方法。文章首先对蘑菇各特征指标与其毒性判别的相关性进行了探究,其所得结果显示蘑菇的气味和颜色是其区分度最大的特征,该结果与人工判别积累的经验相符。接着构建宽度学习系统并进行训练,对比分析不同样本量情况下所提方法的准确率,发现当样本数量大于1000时,宽度学习系统分类准确率便高于99.5%。与BP-神经网络相比,该方法准确率高且所需训练时间短。最后依据宽度学习系统的增量学习算法,在模型性能不满足要求时,通过增加隐藏层节点快速更新系统,使系统分类准确率从98.55%提升至99.99%,而不需要将网络重新进行训练,这使实时判别蘑菇毒性成为可能。因此对比其他方法,基于宽度学习系统的蘑菇毒性判别方法具有准确率高、训练时间短、判别迅速且易拓展的优点。

关键词：毒蘑菇机器学习宽度学习系统

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“Slope-adsorption & plateau-pore filling” mechanism unlocking the potential of hard carbon anodes for “fast-charging & large-sized”batteries

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Science China Materials 2025年第1期 309-311页

作者： Tian liang Xiaoming zhu Hubei Key Laboratory of Radiation Chemistry and Functional Materials School of Nuclear Technology and Chemistry & Biology Hubei University of Science and Technology

To date, there has been no report on fast-charging and Ahlevel sodium-ion batteries (SIBs) by utilizing thick hard carbon anodes that demonstrate prolonged cycling life and high areal capacity at high rates. Further, the relationship among the complex structure of hard carbon, storage mechanism, and fastcharging performance in alkali-metal ion batteries has been a subject of ongoing debate [1,2].

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某沿海吹填土堤边坡稳定的颗粒流细观模拟分析

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水电能源科学 2016年第3期34卷 148-151页

作者：王鑫诸裕良河海大学港口海岸与近海工程学院江苏南京210098 上海交通建设总承包有限公司上海200136

针对浙江省宁波市沿海某围垦吹填土堤边坡稳定问题,引入颗粒流方法,借助颗粒流双轴试验标定吹填土细观参数,给出了颗粒流法土堤边坡失稳的判据,建立吹填土堤颗粒流分析模型,分别利用强度折减法和重力增加法分析了该土堤边坡的稳定性。... 详细信息

针对浙江省宁波市沿海某围垦吹填土堤边坡稳定问题,引入颗粒流方法,借助颗粒流双轴试验标定吹填土细观参数,给出了颗粒流法土堤边坡失稳的判据,建立吹填土堤颗粒流分析模型,分别利用强度折减法和重力增加法分析了该土堤边坡的稳定性。结果表明,可直接观察土堤的失稳破坏过程和滑动面的形成;发现整个堤坡表现出上部受拉、中部受剪、底部受压的破坏形式;颗粒流法中的重力增加法的安全系数和强度折减法一致,但其边坡破坏表现为浅层滑动;对比颗粒流法与刚体极限平衡法的计算结果,两者滑坡面形状相似,但安全系数有所偏差。该方法可为沿海吹填土堤边坡设计提供参考依据。

关键词：吹填土堤边坡稳定颗粒流双轴试验强度折减法

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人工采沙及航道整治对珠江三角洲水流动力条件的影响

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水利学报 2008年第9期39卷 1098-1104页

作者：张蔚严以新诸裕良杨明远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 广东省航道局广东广州510150

本文借助数值计算,运用"三级联合解法"对圣维南方程组进行求解,对1990年和2005年实测地形条件下珠江三角洲动力条件进行复演,研究了在高强度、大范围人工采沙和航道整治等人类活动作用下,三角洲航道网内部水流动力条件的变化。研究结果... 详细信息

本文借助数值计算,运用"三级联合解法"对圣维南方程组进行求解,对1990年和2005年实测地形条件下珠江三角洲动力条件进行复演,研究了在高强度、大范围人工采沙和航道整治等人类活动作用下,三角洲航道网内部水流动力条件的变化。研究结果表明:由于河床的下切,导致同流量水位下降明显,一级分流节点思贤站的百年一遇流量水位下降达2.68m;同时,由于河槽容积增加,航道网内部潮汐动力增强,该站的年均潮差从1990年的0.35m增加到2005年的0.53m。河道断面面积的剧烈变化,引起了航道网内部及口门处水量的重新分配,其中洪奇门和磨刀门流量增加显著,其余6个口门均有不同程度的减少。珠江三角洲航道网内部水流动力条件的变化,亦是近年来珠江三角洲咸灾频发的主要诱因之一。

关键词：珠江三角洲河网采沙潮汐动力水流动力变化

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