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DEVELOPMENT OF COUPLED 1D-2D MATHEMATICAL MODELS FOR TIDAL RIVERS

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Journal of Hydrodynamics 2004年第6期16卷 767-776页

作者： XUZu-xin YINHai-long StateKeyLaboratoryofPollutionControlandResourceReuse TongjiUniversityShanghai200092.China

Some coupled 1D-2D hydrodynamic and water quality models depicting tidalwater bodies with complex topography were presented. For the coupled models, finite element methodwas used to solve the governing equations so as to study tidal rivers with complex topography. Sincethe 1D and 2D models were coupled, the principle of model coupling was proposed to accountappropriately for the factors of water level, flow and pollutant flux and the related dynamicalbehavior was simulated. Specifically the models were used to probe quantitative pollutioncontribution of receiving water from neighboring Jiangsu and Zhejiang Provinces to the pollution inthe Huangpu River passing through Shanghai City, Numerical examples indicated that the developedcoupled 1D-2D models are applicable in tidal river network region of Shanghai.

关键词： tidal river hydrodynamic water quality coupled model Huangpu River Shanghai

Fuzzy Zorn’s lemma with applications

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 521-536页

作者： xin Xiao-long FU Yu-long School of Science Xi’an Polytechnic UniversityXi’an 710048China School of Mathematics Northwest UniversityXi’an 710127China School of Cyber Engineering Xidian UniversityXi’an 710071China

We introduced the fuzzy axioms of choice,fuzzy Zorn’s lemma and fuzzy well-ordering principle,which are the fuzzy versions of the axioms of choice,Zorn’s lemma and well-ordering principle,and discussed the relations among *** an application of fuzzy Zorn’s lemma,we got the following results:(1)Every proper fuzzy ideal of a ring was contained in a maximal fuzzy ideal.(2)Every nonzero ring contained a fuzzy maximal ideal.(3)Introduced the notion of fuzzy nilpotent elements in a ring R,and proved that the intersection of all fuzzy prime ideals in a commutative ring R is the union of all fuzzy nilpotent elements in R.(4)Proposed the fuzzy version of Tychonoff Theorem and by use of fuzzy Zorn’s lemma,we proved the fuzzy Tychonoff Theorem.

关键词： fuzzy axioms of choice fuzzy Zorn’s lemma fuzzy well-ordering principle fuzzy ideal of a ring fuzzy Tychonoff Theorem

Interaction Mechanism of the Parametrically Excited Solitons

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Chinese Physics Letters 1998年第12期15卷 859-861页

作者： WANG xin-long Institute of Acoustics and State Key Laboratory of Modern Acoustics Nanjing UniversityNanjing 210093

The parametrically excited solitons manifest themselves with many distinct particle-like *** the internal dynamics of the soliton-soliton interactions is explored both analytically and *** results confirm the attraction between polarity-like solitons and the repulsion between opposite polarity *** attraction can make a pair of like polarity solitons form a standing(or oscillating)bound ***,multisolitons in an unbounded waveguide would asymptotically develop into an array of mutually independent standing soliton(s)or/and the bound state(s).It is shown that the bound state has two unidirectional momenta flowing toward the symmetric center,and thus the solitons do not perform the collisions in the classical *** is further demonstrated that the observed periodic“collisions”are actually due to the dissipative-induced collapses and the parametric recreations of solitons.

关键词： soliton solitons polarity

Dynamics of Soliton-Soliton Interactions in Parametrically-Driven Systems

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Chinese Physics Letters 1997年第2期14卷 109-112页

作者： WANG xin-long Institute of Acoustics Nanjing UniversityNanjing 210093

The parametrically-driven,damped nonlinear Schrodinger equation is numerically investigated and the parameter regions for the double-solitons of like polarity are *** simulations of the soliton evolution in the parameter regions are in good agreement with the experimental *** computations also reveal that the“particles number”,momentum and energy are no more constants but vary in a periodic fashion in the system.

关键词： Soliton soliton momentum

Numerical investigation of the influence of vortex generator on propeller cavitation and hull pressure fluctuation by DDES

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Journal of Hydrodynamics 2022年第3期34卷 444-450页

作者： Yun long Han-qiao Han Bin Ji xin-ping long Wuhan Second Ship Design and Research Institute Wuhan430064China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China

In this study,the delayed detached eddy simulation(DDES)is coupled with a homogenous cavitation model to simulate the cavitating turbulent flow around a propeller behind a full body ship with special emphasis on the influence of the vortex generator(VG)on the propeller cavitation and the hull pressure *** small calculation uncertainty as evaluated by the DDES verification and validation(V&V)method indicates that the present simulation can accurately reproduce the propeller performance and cavitation,and the predicted hull pressure fluctuation is in a fairly good agreement with the available experimental *** mechanism is explored through the current numerical results how the VG affects the local velocity distribution,along with the influences of the VG on the propeller cavitation and the hull pressure *** is shown that the streamwise vortex is induced by the VG near the hull boundary *** very low velocity region in the hull wake is reduced due to the effect of the streamwise ***,the propeller cavitation develops more mildly and the hull pressure fluctuation decreases due to the influence of the VG.

关键词： Propeller cavitation delayed detached eddy simulation(DDES) vortex generator(VG) streamwise vortex

Anick Resolution and the Minimal Projective Resolution of U_(q)+(C_(3))

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Acta Mathematica Sinica,English Series 2023年第6期39卷 1022-1052页

作者： Ling Ling MAO Xiao long xin School of Mathematics Northwest UniversityXi'an 710127P.R.China School of Science Xi'an Polytechnic UniversityXi'an 710048P.R.China

In this paper,from the Anick’s resolution and Grobner-Shirshov basis for quantized enveloping algebra of type C_(3),we compute the minimal projective resolution of the trivial module U_(q)+(C_(3))and as an applicatio... 详细信息

关键词： Anick resolution minimal projective resolution Grobner-Shirshov basis global dimension

Design Optimization of Pillar Bump Structure for Minimizing the Stress in Brittle Low K Dielectric Material Layer

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Acta Metallurgica Sinica(English Letters) 2020年第4期33卷 583-594页

作者： xin-Jiang long Jin-Tang Shang Li Zhang Key Laboratory of MEMS of Ministry of Education Southeast UniversitySipailou 2#Nanjing 210096China Jiangyin Changdian Advanced Packaging Co. Ltd.No.275 Binjiang RdJiangyin 214400China

Cu pillar bump offers a number of advantages for flip chip packaging,compared to the conventional solder ***,due to its rigidity structure,Cu pillar bump introduces a lot of stress to the chip,which causes the failure of packaging structures,especially for the advanced node devices which typically have brittle low K dielectric *** this paper,for the first time we propose two types of Cu pillar structures to reduce the *** first Cu pillar structure has bigger Cu dimensions at the *** other one is designed to add an additional Cu pad under the Cu pillar *** element analysis is used to study the stress of the both structures,and it is found that with the increase in pillar bump contact area over the chip surface,the stress decreases in both *** also indicate that the Cu pillar bump undercut induces higher stress,and thin Cu6 Snss intermetallic compound has less impact on the stress during flip chip mount *** study provides a novel way to improve the reliability by reducing the stress in the Cu pillar bump related packaging.

关键词： Cu pillar bump Flip chip Low K stress Undercut

Some Results on Space-Like Self-Shrinkers

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Acta Mathematica Sinica,English Series 2016年第1期32卷 69-82页

作者： Hua Qiao LIU Yuan long xin School of Mathematics and Information Sciences He'nan University Institute of Mathematics Fudan University

We study space-like self-shrinkers of dimension n in pseudo-Euclidean space Rm^m＋n with index m. We derive drift Laplacian of the basic geometric quantities and obtain their volume estimates in pseudo-distance function. Finally, we prove rigidity results under minor growth conditions in terms of the mean curvature or the image of Gauss maps.

关键词： Space-like self-shrinker pseudo-distance volume growth rigidity

Neural networks for optimal approximation of continuous functions in R^d

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Applied Mathematics(A Journal of Chinese Universities) 2012年第3期27卷 335-344页

作者： XIE Ting-fan ZHOU xin-long Department of Mathematics China Jiliang University310018 HangzhouChina Department of Mathematics University of Duisburg-Essen47048 DuisburgGermany

Using some regular matrices we present a method to express any multivariate algebraic polynomial of total order n in a normal form. Consequently, we prove constructively that, to approximate continuous target function... 详细信息

关键词： approximation rate neural network ridge function sigmoidal function.