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Observation and modeling of tide- and wind-induced surface currents in Galway Bay

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Water Science and Engineering 2015年第4期8卷 345-352页

作者： lei Ren Stephen Nash Michael Hartnett Department of Civil Engineering College of Engineering and Informatics National University of Ireland

A high-frequency radar system has been deployed in Galway Bay, a semi-enclosed bay on the west coast of Ireland. The system provides surface currents with fine spatial resolution every hour. Prior to its use for model validation, the accuracy of the radar data was verified through comparison with measurements from acoustic Doppler current profilers （ADCPs） and a good correlation between time series of surface current speeds and directions obtained from radar data and ADCP data. Since Galway Bay is located on the coast of the Atlantic Ocean, it is subject to relatively windy conditions, and surface currents are therefore strongly wind-driven. With a view to assimilating the radar data for forecasting purposes, a three-dimensional numerical model of Galway Bay, the Environmental Fluid Dynamics Code （EFDC）, was developed based on a terrain-following vertical （sigma） coordinate system. This study shows that the performance and accuracy of the numerical model, particularly with regard to tide- and wind-induced surface currents, are sensitive to the vertical layer structure. Results of five models with different layer structures are presented and compared with radar measurements. A variable vertical structure with thin layers at the bottom and the surface and thicker layers in the middle of the water column was found to be the optimal layer structure for reproduction of tideand wind-induced surface currents. This structure ensures that wind shear can properly propagate from the surface layer to the sub-surface layers, thereby ensuring that wind forcing is not overdamped by tidal forcing. The vertical layer structure affects not only the velocities at the surface layer but also the velocities further down in the water column.

关键词： Wind-induced surface current Vertical layer structure High-frequency radar Coastal ocean dynamics application radar Environmental fluid dynamicscode Galway Bay

Functionalized periodic mesoporous organosilicas: Hierarchical and chiral materials

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Science China Chemistry 2010年第2期53卷 351-356页

作者： YANG QiHua LIU Jian ZHANG lei State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

The integration of organic and inorganic fragments within the pore walls of the periodic mesoporous organosilicas (PMOs) represents one of the recent breakthroughs in material science. The resulting PMOs are promising materials for applications in such areas as catalysis, adsorption, separation and drug-delivery. We summarize here the recent progress made in the synthesis of PMOs with hierarchical structures and large functional groups, with special emphasis on the chiral mesoporous organosilicas and their potential applications as novel chiral solids in heterogeneous asymmetric catalysis.

关键词： periodic mesoporous organosilicas chiral hierarchical

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一种低功耗可级联拓展的电刺激IC

半导体技术 2025年第1期50卷 64-70页

作者：吴黎霞张轩薛宁姚镭刘春秀中国科学院空天信息创新研究院传感器技术国家重点实验室北京100094 中国科学院大学电子电气与通信工程学院北京100094 上海矩智科技有限公司上海201899 临港实验室上海200031

设计了一种低功耗可级联拓展的电刺激芯片,该芯片主要由16个独立电刺激通道、一个全局数字控制器(GDC)及电流偏置模块组成。每个独立电刺激通道包含一个8 bit数模转换器(DAC)、一个高压刺激前端(SFE)电路以及通道本地数字控制器(LDC),... 详细信息

设计了一种低功耗可级联拓展的电刺激芯片,该芯片主要由16个独立电刺激通道、一个全局数字控制器(GDC)及电流偏置模块组成。每个独立电刺激通道包含一个8 bit数模转换器(DAC)、一个高压刺激前端(SFE)电路以及通道本地数字控制器(LDC),能够输出脉冲幅度/宽度/相位间隔时间可独立配置的单极性双相脉冲刺激电流。GDC控制16个通道的配置和刺激使能,并有一个可进行多芯片级联拓展的控制接口。LDC和GDC共用同一组时钟/数据控制信号,节省了端口资源。提出的电路采用GF 0.18μm CMOS BCD高压工艺进行设计和制备,总面积为1.5 mm×3.1 mm。测试结果表明,在5 V/15 V/-15 V供电下,该电路的静态功耗为2.14μW,最大输出电流为1 mA,输出200μA恒定电流时顺从电压为13.5 V。

关键词：电刺激集成电路(IC) 低功耗可拓展性多通道电刺激器

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淮安市水资源保护现状及对策措施

水利技术监督 2025年第1期 73-76页

作者：鞠伟韩磊张新星江苏省水文水资源勘测局淮安分局江苏淮安223005

文章为总结和推进淮安市水资源保护工作,保障淮安市饮水安全和良好河湖生态,在研究淮安市水资源保护现状的基础上,结合最严格水资源管理制度及高质量发展需求,分析当前水资源保护工作中存在问题,提出了加强饮用水源地保护、水生态环境... 详细信息

文章为总结和推进淮安市水资源保护工作,保障淮安市饮水安全和良好河湖生态,在研究淮安市水资源保护现状的基础上,结合最严格水资源管理制度及高质量发展需求,分析当前水资源保护工作中存在问题,提出了加强饮用水源地保护、水生态环境保护与修复、提高水资源空间管护能力、提升水资源保护信息化水平等对策措施,以期为实现地方水资源的可持续保护与合理利用提供借鉴。

关键词：水资源保护存在问题对策措施淮安市

Dual-stage constructed random graph algorithm to generate random graphs featuring the same topological characteristics with power grids

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Journal of Modern Power Systems and Clean Energy 2017年第5期5卷 683-695页

作者： Shiqian MA Yixin YU lei ZHAO State Grid Tianjin Electric Power Research Institute Tianjin 300384China Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China

It is a common practice to simulate some historical or test systems to validate the efficiency of new methods or concepts. However, there are only a small number of existing power system test cases, and validation and evaluation results, obtained using such a limited number of test cases, may not be deemed sufficient or convincing. In order to provide more available test cases, a new random graph generation algorithm, named ‘‘dualstage constructed random graph’’ algorithm, is proposed to effectively model the power grid topology. The algorithm generates a spanning tree to guarantee the connectivity of random graphs and is capable of controlling the number of lines precisely. No matter how much the average degree is,whether sparse or not, random graphs can be quickly formed to satisfy the requirements. An approach is developed to generate random graphs with prescribed numbers of connected components, in order to simulate the power grid topology under fault conditions. Our experimental study on several realistic power grid topologies proves that the proposed algorithm can quickly generate a large number of random graphs with the topology characteristics of real-world power grid.

关键词： Power gird topology Dual-stage constructed random graph(DSCRG)algorithm Random graph generation Connectivity Average degree Connected component

Characteristics of trace elements of the No.9 coal seam from the Anjialing Mine, Ningwu coalfield, China

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Chinese Journal Of Geochemistry 2015年第3期34卷 391-400页

作者： Wang Jinxi Wang Qi Tian lei Key Laboratory of Resource Exploration Research of Hebei Province Hebei University of Engineering

Trace elements of the No. 9 coal seam from Aanjialing mine were measured by ICP–MS. The results indicated that Li, Ga, Cr, Sr, Zr and Pb are significantly enriched in the No. 9 coal seam. The Li and Ga contents in most of the coal seam samples reached an economically valuable level. Most trace elements were enriched near the roof and floor. The data from the Sr/Ba, V/Zn, Th/U, V/Zr and V/Ni ratios reveal that during this period, the peat swamp from this area was formed in swamp water, which was influenced by sea-water or, in an sea-land transition environment, where the ancient water salinity was slightly high. The Eu negative anomaly obviously shows that the rare earth elements are consistent with the terrigenous rocks, so we deduced that the rare earth elements contained in the mineral may mainly come from terrestrial detritus.

关键词：微量元素特征宁武煤田煤层煤矿微量元素富集陆源碎屑岩中国 ICP-MS

Assembling ZnO Nanorods into Microflowers through a Facile Solution Strategy: Morphology Control and Cathodoluminescence Properties

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Nano-Micro Letters 2012年第1期4卷 45-51页

作者： Ying lei Fengyu Qu Xiang Wu Key Laboratory of Semiconductor Nanocomposite Materials Ministry of Education and College of Chemistry and Chemical EngineeringHarbin Normal University

In this work, flowerlike ZnO micro/nanostructures assembled from nanorods are obtained through a facile hydrothermal route. The experimental results indicated that the as-synthesized ZnO microflowers have an average diameter of 2 μm, composed of nanorods of an average diameter of 200 nm and a tapered *** with other morphologies were also obtained by varying the reaction conditions. Systematical conditiondependent experiments were conducted to reveal the growth mechansim of the microflowers. It is suggested that the zinc source types, solution p H value, and reaction temperature, as well as reaction time are responsible for the variations of ZnO morphology. luminescence properties of ZnO microflowers were investigated through monitoring different parts of nanorods, showing good optical quality.

关键词： Microflowers Solution growth Zn O Cathodoluminescence

Unconventional Hamilton-type variational principles for electromagnetic elastodynamics

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 119-128页

作者： luO En ZHU Huijian YUAN lei Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China

According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified new way proposed by luo, the unconventional Hamilton-type variational principles for electromagnetic elastodynamics can be established systematically. This new variational principles can fully characterize the initial-boundary-value problem of this dynamics. In this paper, the expression of the generalized principle of virtual work for electromagnetic dynamics is given. Based on this equation, it is possible not only to obtain the principle of virtual work in electromagnetic dynamics, but also to derive systematically the complementary functionals for eleven-field, nine-field and six-field unconventional Hamilton-type variational principles for electromagnetic elastodynamics, and the potential energy functionals for four-field and three-field ones by the generalized Legendre transformation given in this paper. Furthermore, with this approach, the intrinsic relationship among various principles can be explained clearly.

关键词： electromagnetic elastodynamics, unconventional Hamilton-type variational principle, principle of virtual work, dual-complementarity, initial-boundary-value problem.

A magnetically driven origin for the low luminosity GRB 170817A associated with GW170817

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Research in Astronomy and Astrophysics 2018年第6期18卷 59-64页

作者： Hao Tong Cong Yu lei Huang School of Physics and Electronic Engineering Guangzhou University School of Physics and Astronomy Sun Yat-sen University Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

The gamma-ray burst GR170817 A associated with GW170817 is subluminous and subenergetic compared with other typical short gamma-ray bursts. It may be due to a relativistic jet viewed off-axis, or a structured jet or cocoon emission. Giant flares from magnetars may possibly be ruled ***, the luminosity and energetics of GRB 170817 A are coincident with those of magnetar giant flares. After the coalescence of a binary neutron star, a hypermassive neutron star may be formed. The hypermassive neutron star may have a magnetar-strength magnetic field. During the collapse of this hypermassive neutron star, magnetic field energy will also be released. This giant-flare-like event may explain the luminosity and energetics of GRB 170817 A. Bursts with similar luminosity and energetics are expected in future neutron star-neutron star or neutron star-black hole mergers.

关键词： stars: magnetar stars: neutron gamma-ray bursts: individual(GRB 170817A) gravitational waves