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A three-dimensional modeling of the morphological change in the Liaodong Bay

Frontiers of Earth Science 2015年第3期9卷 509-520页

作者： qiushun wang haigui kang State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

The morphology in the Liaodong Bay has undergone a marked change over the past decades due to the cutoff of nearby rivers. The fine sediment of the bay consists of both non-cohesive and cohesive fractions with relatively small particles over the seabed. Thus, a three- dimensional morphodynamic model accounting for non- cohesive and cohesive fractions is established to investi- gate the morphological change without sediment input from nearby rivers. A representative wave is chosen to compute the wave distribution in the Liaodong Bay and depth-dependent wave radiation stresses are employed by the hydrodynamic model. The advection-diffusion equa- tion is used to simulate the fine sediment transport under the representative wave and tidal currents. The erosion flux of non-cohesive and cohesive sediment is taken into account. The simulated results of tidal level, velocities, directions, and sediment concentrations are in agreement with the measured data. The results demonstrate that the present model, which takes the erosion flux of both non- cohesive and cohesive fractions into account, gives more reasonable values than when accounting for cohesive sediment alone. When the three-dimensional morphody- namic model is applied to predict morphological change over the course of a year, the deposition is shown to be relatively small and the range of the erosion is increased compared to previous results of sediment input from the river. It can be concluded that the erosion in the Liaodong Bay is increasing due to the cutoff of the river, and that morphological evolution must be taken into account if any type of coastal construction plans are to be carried out over the seabed.

关键词： fine sediment three-dimensional model morphological change representative wave

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Highly efficient optics/microwave beam splitter based on frequency selective surface

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Chinese Optics Letters 2024年第6期22卷 136-141页

作者： Qiao Sun Nianxi Xu haigui Yang Dongzhi Shan Yang Tang Xin Chen Tongtong wang Jinsong Gao Yu Cai Key Laboratory of Optical System Advanced Manufacturing Technology Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China Jilin Provincial Key Laboratory of Advanced Optoelectronic Equipment and Instrument Manufacturing Technology Changchun 130033China Unit 96951 of the People’s Liberation Army Beijing 100039China

The development of hybrid optics/microwave communication systems puts forward a new requirement for beam splitters to efficiently transmit microwave signals and simultaneously reflect optical signals. Owing to mechanical constraints, the physical thickness of beam splitters is of the order of tens of millimeters. The corresponding electrical thickness has the same order of magnitude as microwave wavelengths, and the resulting multi-beam interference effect significantly reduces the microwave transmittance, impacting the beam splitting *** study presents a new optics/microwave beam splitter based on the ability of the frequency selective surface(FSS) to shape the resonant curve. A beam splitter sample,whose physical thickness and substrate material are 20 mm and quartz glass, respectively, is designed, simulated, fabricated, and characterized to validate the feasibility of this strategy. The measured results show that the minimum microwave transmittance between 35 and 36.5 GHz with an incidence angle of 45° under TE polarization is 86.43%, and the mean value of the reflectance spectra from 450 to 900 nm and that from 7.7 to 10.5 μm both exceed 96%. This FSS-based optics/microwave beam splitter is expected to play a key role in hybrid optics/microwave communication systems.

关键词： beam splitter multi-beam interference frequency selective surface high transmission

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钱塘江河口治江缩窄对涌潮的影响

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水科学进展 2024年第3期35卷 496-507页

作者：鲁海燕潘存鸿胡成飞汪求顺曹颖曾剑浙江省水利河口研究院(浙江省海洋规划设计研究院) 浙江杭州310020 浙江省河口海岸重点实验室浙江杭州310020

20世纪60年代后期以来,钱塘江河口进行了大规模的治江缩窄,显著改变了河口的水沙、地貌及其相互作用过程,而对于涌潮在高强度人类活动扰动下的响应认知尚不全面。基于实测资料,结合涌潮数学模型分析大规模治江缩窄对钱塘江河口潮汐、河... 详细信息

20世纪60年代后期以来,钱塘江河口进行了大规模的治江缩窄,显著改变了河口的水沙、地貌及其相互作用过程,而对于涌潮在高强度人类活动扰动下的响应认知尚不全面。基于实测资料,结合涌潮数学模型分析大规模治江缩窄对钱塘江河口潮汐、河床以及涌潮的影响。结果表明:治江缩窄后,滩槽分布基本稳定;山潮水比增大,大致以盐官为界,涌潮河段下游段淤积,上游段冲刷,沙坎下移;高潮位沿程抬升,涌潮起潮点附近及闸口—仓前河段潮差增大,仓前—盐官河段潮差减小;涌潮起潮点和最大涌潮位置下移,观潮位置固定,潮景丰富稳定,潮到时间稳定,涌潮高度变幅减小,仓前—盐官河段涌潮高度减小。为保护涌潮,需要在涌潮河段维持较大的潮差和适宜的水深,不宜开展大规模的缩窄。

关键词：涌潮潮汐治江缩窄沙坎钱塘江河口

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Wave-Current Forces on Slender Circular Cylinders

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China Ocean Engineering 1991年第3期6卷 287-310页

作者： Li, Yucheng wang, Fenglong kang, haigui Dalian Univ of Technology Dalian China

A series model tests of wave forces by both regular and irregular waves combined with currents on single piles and bipiles in tandem and parallel arrays have been carried out. Based on Morison Equation, linear wave theory and linear wave spectrum theory as well, the characteristics of inline, lift and resultant forces on cylinders have been analyzed respectively. The drag, inertia and lift coefficients CD, CM and CL for single piles related to KC number and the grouping effect coefficients of inline, lift and resultant forces on bipiles in tandem and parallel arrays related to KC number are given in this paper.

关键词： Piles Stresses Water Waves Spectrum Analysis

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基于遥感影像的浙江省三门湾近40年海岸线及海岸带时空变化分析

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海洋地质前沿 2024年第4期40卷 60-70页

作者：马苑浩辜鹏周春艳汪求顺河海大学海岸灾害及防护教育部重点实验室南京210098 南京水科院瑞迪科技集团有限公司南京210009 浙江省水利河口研究院杭州310020

根据1985、1995、2005、2013和2020年的Landsat卫星图像,采用人机交互手段将三门湾海岸线分为基岩岸线、砂质岸线、淤泥质岸线、人工岸线和河口岸线。采用交互式监督分类将三门湾海岸带的土地利用分为水体、林地、裸地、建设用地和农业... 详细信息

根据1985、1995、2005、2013和2020年的Landsat卫星图像,采用人机交互手段将三门湾海岸线分为基岩岸线、砂质岸线、淤泥质岸线、人工岸线和河口岸线。采用交互式监督分类将三门湾海岸带的土地利用分为水体、林地、裸地、建设用地和农业用地。研究结果表明:近40年三门湾人工岸线和基岩岸线变化最大,分别增加了80.3 km和减少了79.3 km;近40年三门湾海岸带面积累计增加了130 km^(2),建设用地和水体是围填海新增土地的主要利用类型,主要的土地转移形式为裸地向建设用地、农业用地的转变以及林地转为建设用地;近40年三门湾岸线分形维数由1.22减小至1.201,人工岸线比例和建设用地占比分别上升了13%和22.57%,总体上呈现向海推进、人工化加强的趋势。人类活动是造成三门湾岸线及海岸带变化的主要原因,随着对海岸带保护与合理利用的推进,三门湾海岸带开发利用格局正逐渐稳中向好。

关键词： Landsat卫星图像三门湾岸线时空变化土地利用遥感

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基于局部探测法的外压球壳屈曲载荷设计方法研究

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压力容器 2024年第4期41卷 22-33页

作者：王庆范海贵侯怡航顾文广大连理工大学化工学院辽宁大连116024

由于受外压球形容器的缺陷敏感性不可避免,其屈曲设计是值得关注的课题,因此系统地研究了基于局部探测法的外压条件下的缺陷敏感球壳结构屈曲设计。根据探测结果,提出了3种屈曲载荷设计方法:能量势垒法、最大曲率法、等效缺陷法。在考... 详细信息

由于受外压球形容器的缺陷敏感性不可避免,其屈曲设计是值得关注的课题,因此系统地研究了基于局部探测法的外压条件下的缺陷敏感球壳结构屈曲设计。根据探测结果,提出了3种屈曲载荷设计方法:能量势垒法、最大曲率法、等效缺陷法。在考虑材料属性影响的基础上,详细介绍了3种屈曲载荷设计方法,并通过具有不同几何缺陷的球壳屈曲响应,对提出的设计方法进行对比与验证。研究结果表明,所提出的屈曲载荷设计方法与现行标准相比,能够针对特定的球壳结构,在考虑缺陷敏感性的前提下,给出精细化的屈曲载荷设计结果。利用3种特定结构对该方法进行验证,每种结构最低试验折减因子分别为0.390,0.224,0.290,而通过文中提出的设计方法计算得到的每种结构最高设计折减因子分别为0.315,0.213,0.171,均低于试验值,体现了提出的设计方法的可靠性。

关键词：外压球壳屈曲设计缺陷敏感性局部探测

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Characteristics of river discharge and its indirect effect on the tidal bore in the Qiantang River, China

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International Journal of Sediment Research 2023年第2期38卷 253-264页

作者： Cunhong Pan qiushun wang Dongzi Pan Chengfei Hu Zhejiang Institute of Hydraulics and Estuary Zhejiang Provincial Key Laboratory of Estuary and Coast

Based on field data of river discharge, tide, tidal bore, and riverbed topography, the characteristics of river discharge, the effect of river discharge on riverbed erosion and sedimentation, and the feedback effect of riverbed erosion and sedimentation on the tide and tidal bore in the Qiantang River are analyzed. The results show that the inter-annual and seasonal variation of river discharge in the Qiantang River is noticeable, while the seasonal distribution of river discharge tends to be uniform after the construction of Xin’anjiang Reservoir. River discharge has a major effect on the erosion and sedimentation in the reach from Zhakou to Yanguan. There are laws of riverbed erosion in wet seasons and years and sedimentation in dry seasons and years. Relations in the Zhakou to Yanguan reach among the riverbed volume after the flood season, the mean and maximum river discharge during the flood season, and riverbed volume before the flood season are established. With the riverbed erosion from Zhakou to Yanguan, the low tide level decreases and the tidal range is amplified, and thus, the tidal bore is enhanced. The relation among tidal range, river discharge, and riverbed volume, as well as the one between the tidal bore height and tidal range is established on the basis of the field data. Furthermore, the variation range of tidal bores after the flood season is analyzed in wet and dry years. The indirect effect of the Xin’anjiang Reservoir on the height of the tidal bore is predicted and the mean height of the tidal bore from Zhakou to Yanguan decreases by 0.1-0.2 m.

关键词： Qiantang River Tidal bore Tide River discharge Riverbed erosion Riverbed sedimentation

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基于TFD模型对大小长山岛海域潮流能估算

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太阳能学报 2016年第4期37卷 1057-1063页

作者：郭伟康海贵汪求顺于汀大连理工大学海岸和近海工程国家重点实验室大连116024 中海油研究总院新能源研究中心北京100027

基于潮流场评估的数值模（tidal flow development，TFD）对大连大小长山岛之间海域的潮流场进行数值模拟，得到该海域沿水深平均的潮流场分布。模型计算和实测结果接近，可得出该海域潮流为明显的往复流，最大流速可达到2m／s，较适合... 详细信息

基于潮流场评估的数值模（tidal flow development，TFD）对大连大小长山岛之间海域的潮流场进行数值模拟，得到该海域沿水深平均的潮流场分布。模型计算和实测结果接近，可得出该海域潮流为明显的往复流，最大流速可达到2m／s，较适合进行潮流能开发应用。结合有效影响因子S／F评估方法对该海域潮流能进行评估，大潮期间最大瞬时峰值潮流能储量为90MW，可开发利用总装机容量达到18MW，年平均发电量3．3×10^7kWh。结果表明，该数值模型可有效弥补潮流能流速实测资料不足的问题，为准确评估潮流能储量提供一种有效的方法。

关键词：数值模型大小长山岛 SIF方法潮流能评估

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Gel-tape-casting of aluminum nitride ceramics

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Journal of Advanced Ceramics 2017年第1期6卷 67-72页

作者： qiushun SHANG Zhengjuan wang Jun LI Guohong ZHOU Hailong ZHANG Shiwei wang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Aluminum nitride ceramic sheets were formed for the first time by a novel and simple method,namely gel-tape-casting process,where only two additives were used to prepare the *** (a water-soluble copolymer of isobutylene and maleic anhydride) acted as both dispersant and gelling agent,and PEG (polyethylene glycol) acted as *** the advantages of gel-casting and tape-casting processes,flexible and uniform green tapes were *** rheological properties of AlN slurries were studied to optimize the PIBM content and solids *** drying and debinding,the green sheets were sintered at 1840 ℃ in N2 *** microstructure with average grain size of about 7 μm was observed in the final AlN *** conductivity of the AlN ceramics was 161 W/(m·K).

关键词： AlN ceramic sheets gel-tape-casting PIBM rheological properties microstructure

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Numerical Investigation on Submerged Horizontal Plate

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Marine Science Bulletin 2001年第2期3卷 19-29页

作者： kang haigui(康海贵) wang Ke(王科) Department of Civil Engineering Dalian University of Technology Dalian 116024 Graduate School of Civil Engineering Dalian University of Technology Dalian 116024

Hydrodynamic characters on a horizontal, thin, rigid plate located beneath the free surface are numerically investigated. Assuming a linear, time-harmonic potential flow and utilizing Green identity, the governing Laplace equation can be simplified into Fredholm integral equation ofthe second kind. Supposing linear-order discontinuous elements along intersecting vertical boundaries, and by use of the boundary element method, numerical solution about source strength distribution on the plate can be changed into a series of algebraic equations. The 3D Green function is introduced to set up the integral equations, and the GMRES solver is performed for solving the large dense linear system of equations. The added-mass, damping force and exciting force are evaluated directly from the equations. It is found that the added-mass coefficient becomes negative for a range of frequencies when the plate is sufficiently close to the free surface.

关键词： Submerged plate, Dreen function, Added mass, Damping coefficient

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