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HiGH OrDEr COMPACT MULTiSYMPLECTiC SCHEME FOr COUPLED NONLiNEAr SCHrODiNGEr-KDV EQUATiONS

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Journal of Computational Mathematics 2018年第4期36卷 591-604页

作者： lan wang Yushun wang Jiangsu Key Laboratory of NSLSCS School of Mathematical Sciences Nanjing Normal University Nanjing 210023 China School of Mathematics and information Science Jiangxi Normal University Nanchang 330022 China

in this paper, a novel multisymplectic scheme is proposed for the coupled nonlinear Schrodinger-KdV （CNLS-KdV） equations. The CNLS-KdV equations are rewritten into the multisymplectic Hamiltonian form by introducing some canonical momenta. To simulate the problem efficiently, the CNLS-KdV equations are approximated by a high order compact method in space which preserves N semi-discrete multisymplectic conservation laws. We then discretize the semi-discrete system by using a symplectic midpoint scheme in time. Thus, a full-discrete multisymplectic scheme is obtained for the CNLS-KdV equations. The conservation laws of the full-discrete scheme are analyzed. Some numerical experiments are presented to further verify the convergence and conservation laws of the new scheme.

关键词： Schrodinger-KdV equations High order compact method Conservation law Multisymplectic scheme

Tautological integrals on Symmetric Products of Curves

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Acta Mathematica Sinica,English Series 2016年第8期32卷 901-910页

作者： Zhi lan wang institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

We propose a conjecture on the generating series of Chern numbers of tautological bundles on symmetric products of curves and establish the rank 1 and rank -1 case of this conjecture. Thus we compute explicitly the generating series of integrals of Segre classes of tautological bundles of line bundles on curves, which has a similar structure as Lehn＇s conjecture for surfaces.

关键词： Hilbert schemes tautological sheaves

Experiment and evaluation of wrinkling str.in in a corner tensioned square membrane

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Acta Mechanica Sinica 2014年第3期30卷 430-436页

作者： lan lan Chang-Guo wang Hui-Feng Tan Center for Composite Materials National Key Laboratory of Science and Technology on Advanced Composites in Special EnvironmentsHarbin Institute of Technology

Prediction of wrinkling characteristics is strongly correlated with the str.in perpendicular to wrinkling direc- tion. in this paper, the str.in field of wrinkled membrane is tested by ViC-3D system based on the digital image correlation technique. Experimental results are validated by the tension wrinkling simulation. The experimental str.in perpendicular to wrinkling direction is analyzed in depth. The wrinkling str.in of a square wrinkled membrane under corner tension is extracted from experimental str.in perpendicular to wrinkling direction. A quantitative characterization format of the experimental wrinkling str.in is proposed. A modified prediction method of wrinkling amplitude is presented based on the experimental wrinkling str.in. The re- sults show that the precision of modified prediction model has improved 13.2% compared with the classical prediction model. The results reveal that the modified model can give an accurate prediction of the wrinkling amplitude.

关键词： Membrane structure. Wrinkle Wrinkling str.in.Digital image correlation Wrinkling amplitude

Comparison of Temperature Field Distribution between Cement Preclinkering Technology and Cement Precalcining Technology

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Journal of Wuhan Univer.ity of Technology(Materials Science) 2016年第2期31卷 355-360页

作者：徐迅 wang lan Country State Key Laboratory of Green Building Materials China Building Materials Academy Beijing 100024 China Country State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials Southwest University of Science and Technology Mianyang 62101O China

Through the comparison of calcination conditions between cement preclinkering technology and cement precalcining technology,we studied the characteristics of temperature field distribution of cement preclinkering technology systems including cyclone preheater,preclinkering furnace,and rotary *** used numericalsimulation method to obtain data of temperature field *** results are found by system *** ratio of tailcoalof cement preclinkering technology is about 70%,and raw mealtemperature can reach 1070 ℃.Shorter L/D kiln type of preclinkering technology can obtain more stable calcining zone *** highest solid temperature of cement preclinkering technology is higher than 80 ℃,and high temperature region（〉1450 ℃）length is 2 times,which is beneficialfor calcining clinker and higher clinker *** cement preclinkering technology can obtain more performance temperature filed,which improves both the solid-phase reaction and liquid-phase reaction.

关键词： cement preclinkering technology temperature field distribution kiln production heat balance solve the equation

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas for.ing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan ren Fei Zheng Tingwei Cao Qiang wang international Center for Climate and Environment Science(iCCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Univer.ity of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overtur.ing Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas for.ing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after.its *** a new optimization strategy,the extra freshwater flux(FWF)parameter.is deter.ined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOi)data assimilation and new machine lear.ing methods are adopted to optimize the FWF parameter.in an abrupt 4×CO_(2) for.ing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) for.ing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,accor.ing to their physical relationship with FWF on the interdecadal timescale.

关键词： recovery of AMOC 4×CO_(2)for.ing Key parameter Parameter estimation Data assimilation Machine lear.ing

Multi-dimensional ambiguity function for subarray-based space-time coding radar

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Journal of Systems Engineering and Electronics 2019年第5期30卷 886-896页

作者： lan lan LiAO Guisheng XU Jingwei wang Hanbing National Laboratory of radar Signal Processing Xidian University

Space-time coding radar has been recently proposed and *** is a radar framework which can perform transmit beamfor.ing at the ***,the range resolution decreases when the number of the transmit element increases.A subarray-based space-time coding(sub-STC)radar.is explored to alleviate the range resolution *** the proposed radar configuration,an identical waveform is transmitted and it introduces a small time offset in different *** multidimensional ambiguity function of sub-STC radar.is defined by considering resolutions in multiple domains including the range,Doppler,angle and probing *** on proper.ies of the multi-dimensional ambiguity function of the sub-STC radar with regard to the spatial coverage,resolution performance and low sidelobes are also *** reveal that the range resolution and low sidelobes performance are improved with the proposed approach.

关键词： space-time coding radar multi-dimensional ambiguity function range resolution wide spatial coverage subarray sidelobe

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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international Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin wang Hui Guo Zhenjia Xie Chengjia Shang Collaborative innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu Li Mengyao Li Yude wang National Center for.international research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical island resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heter.interface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2ser.ing as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： internal electric field Cationic accelerator ion diffusion kinetics Cathode modification strategy Aqueous zinc ion battery

基于无人机多光谱数据和氮素空间分异的玉米冠层氮浓度估算

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作物学报 2025年第1期51卷 189-206页

作者：郝琪陈天陆王富贵王振白岚方王永强王志刚内蒙古农业大学农学院内蒙古呼和浩特010010

作物冠层氮素营养的遥感诊断对指导作物精准施氮,提高作物氮效率和产量具有重要意义。本研究针对玉米冠层纵深大影响无人机估算氮浓度精度的问题,基于2022年和2023年不同氮肥运筹处理下田间无人机多光谱数据和氮浓度实测数据,分析玉米... 详细信息

作物冠层氮素营养的遥感诊断对指导作物精准施氮,提高作物氮效率和产量具有重要意义。本研究针对玉米冠层纵深大影响无人机估算氮浓度精度的问题,基于2022年和2023年不同氮肥运筹处理下田间无人机多光谱数据和氮浓度实测数据,分析玉米冠层氮浓度空间分布特征,并利用随机森林算法确定估算冠层氮浓度的有效叶层。进一步结合随机森林算法和多光谱植被指数构建有效叶层氮浓度估算模型,最终将有效叶层氮浓度转换到冠层尺度实现冠层氮浓度的估算。结果表明:(1)九叶展期和大喇叭口期玉米冠层氮浓度表现为上层叶片>中层叶片>下层叶片,吐丝期和乳熟期表现为中层叶片>上层叶片>下层叶片。(2)各时期估算冠层氮浓度的有效叶层分别为下层、中层、中层和中层。与支持向量回归模型相比,随机森林回归估算冠层氮浓度的精度较高。(3)结合随机森林算法,基于有效叶层氮浓度估算冠层氮浓度的平均rMSE、NrMSE和MAE分别为0.10%、4.41%和0.07%,而直接基于植被指数估算冠层氮浓度的平均rMSE、NrMSE和MAE分别为0.19%、9.00%和0.15%。综上,玉米冠层氮浓度存在空间分异特征,估算冠层氮浓度时考虑基于随机森林和植被指数估算的有效叶层氮浓度能明显提高冠层氮浓度的估算精度。本研究确定的考虑空间分异的冠层氮浓度估算框架可为玉米氮素营养实时诊断提供理论支撑。

关键词：玉米冠层氮浓度氮素空间分异多光谱数据机器学习