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SOLUTION OF 2D SHALLOW WATER EQUATIONS BY GENUINELY MULTIDIMENSIONAL SEMI-DISCRETE CENTRAL SCHEME

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Journal of Hydrodynamics 2006年第4期18卷 436-442页

作者： chen jian-zhong, shi zhong-ke College of Automation Northwestern Polytechnical University Xi＇an 710072 China

A numerical two-dimensional shallow water method was based on method for solving the equations was presented. This the third-order genuinely multidimensional semi-discrete central scheme for spatial discretization and the optimal third-order Strong Stability Preserving （SSP） Runge-Kutta method for time integration. The third-order compact Central Weighted Essentially Non-Oscillatory （CWENO） reconstruction was adopted to guarantee the non-oscillatory behavior of the presented scheme and improve the resolution. Two kinds of source terms were considered in this work. They were evaluated using different approaches. The resulting scheme does not require Riemann solvers or characteristic decomposition, hence it retains all the attractive features of central schemes such as simplicity and high resolution. To evaluate the performance of the presented scheme, several numerical examples were tested. The results demonstrate that our method is efficient, stable and robust.

关键词： 2D shallow water equations semi-discrete central scheme Central Weighted Essentially Non-Oscil]atory (CWENO) reconstruction

A relaxation scheme for a multi-class Lighthill-Whitham-Richards traffic flow model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1835-1844页

作者： jian-zhong chen zhong-ke shi Yan-mei HU College of Automation Northwestern Polytechnical University Xi 'an 710072 China College of Science Chang 'an University Xi 'an 710064 China

We present a high-resolution relaxation scheme for a multi-class Lighthill-Whitham-Richards (MCLWR) traffic flow model. This scheme is based on high-order reconstruction for spatial discretization and an implicit-explicit Runge-Kutta method for time integration. The resulting method retains the simplicity of the relaxation schemes. There is no need to involve Riemann solvers and characteristic decomposition. Even the computation of the eigenvalues is not required. This makes the scheme particularly well suited for the MCLWR model in which the analytical expressions of the eigenvalues are difficult to obtain for more than four classes of road users. The numerical results illustrate the effectiveness of the presented method.

关键词： Relaxation scheme Multi-class LWR model Traffic flow CWENO reconstruction Implicit-explicit Runge-Kutta

Numerical solutions of a multi-class traffic flow model on an inhomogeneous highway using a high-resolution relaxed scheme

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第1期13卷 29-36页

作者： jian-zhong chen zhong-ke shi Yan-mei HU College of Automation Northwestern Polytechnical University Xi＇an 710072 China College of Science Chang ＇an University Xi ＇an 710064 China

A high-resolution relaxed scheme which requires little information of the eigenstructure is presented for the multiclass Lighthill-Whitham-Richards （LWR） model on an inhomogeneous highway. The scheme needs only an estimate of the upper boundary of the maximum of absolute eigenvalues. It is based on incorporating an improved fifth-order weighted essentially non-oscillatory （WENO） reconstruction with relaxation approximation. The scheme benefits from the simplicity of relaxed schemes in that it requires no exact or approximate Riemann solvers and no projection along characteristic directions. The effectiveness of our method is demonstrated in several numerical examples.

关键词： Relaxed scheme Multi-class model Weighted essentially non-oscillatory (WENO) reconstruction

α-clustering effect on flows of direct photons in heavy-ion collisions

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Nuclear Science and Techniques 2021年第6期32卷 122-132页

作者： chen-zhong shi Yu-Gang Ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China University of the Chinese Academy of Sciences Beijing 100080China

In this study,we reconstruct theγ-photon energy spectrum,which is in good agreement with the experimental data of ^(86)Kr+^(12)C at E/A=44 Me V within the framework of the modified EQMD *** directed and elliptic flows of free protons and direct photons were investigated by considering theα-clustering structure of ^(12)*** with free protons,direct photon flows provide clearer information about the early stage of a nuclear *** difference in the collective flows between different configurations of ^(12)C is observed in this *** indicates that the collective flows of direct photons are sensitive to the initial ***,theγbremsstrahlung process might be taken as an alternative probe to investigate theα-clustering structure in a light nucleus from heavy-ion collisions within the Fermienergy region.

关键词： Nuclear reaction Direct photon Collective flow α-clustering configuration

Optimal Grading Policies in the Online Acquisition of Used Products

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Journal of Systems Science and Systems Engineering 2021年第1期30卷 29-43页

作者： Xiang Chu zhong Wen jian chen School of Maritime Economics and Management Dalian Maritime UniversityDalian116026China International Business School Beijing Foreign Studies UniversityBeijing100089China School of Economics and Management Tsinghua UniversityBeijing100084China

Although online reverse commerce(recommerce)is convenient and efficient,it is not without *** limits recommerce firms’flexibility to offer personalized prices and may cause mismatched grading between the firms and sellers of used *** study examines a recommerce firm’s decision on grading criteria and *** find that the firm’s optimal policy exhibits two distinctly different patterns depending on the trade value of the *** demonstrate that sellers’overestimate and underestimate errors have qualitatively different effects on firm profitability,and the effects crucially rely on the type of optimal *** findings can apprise firms on how to preset sorting criteria and prices as well as reduce grading errors.

关键词： Closed-loop supply chains used-product acquisition management recommerce grading error grading policy

On exponential stability for systems with state delays

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1296-1303页

作者： chen Yun XUE An-ke GE Ming WANG jian-zhong LU Ren-quan Institute of Operational Research and Cybernetics Hangzhou Dianzi University Hangzhou 310018 China National Laboratory of Industrial Control Technology. Zhejiang University Hangzhou 310027 China Institute of Information and Control Hangzhou Dianzi University. Hangzhou 310018 China

This paper considers the issue of delay-dependent exponential stability for time-delay systems. Both nominal and uncertain systems are investigated. New sufficient conditions in terms of linear matrix inequalities(LMIs) are obtained. These criteria are simple owing to the use of an integral inequality. The model transformation approaches,bounding techniques for cross terms and slack matrices are all avoided in the derivation. Rigorous proof and numerical examples showed that the proposed criteria and those based on introducing slack matrices are equivalent.

关键词： Exponential stability Uncertain time-delay systems Integral inequality Slack matrix Linear matrix inequality (LMI)

Effect of Coagulation and Diffusion on Nanoparticle Distribution in a Fully Developed Turbulent Boundary Layer

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Chinese Physics Letters 2012年第5期29卷 157-160页

作者： LIN jian-zhong chen zhong-Li Department of Mechanics Zhejiang UniversityHangzhou 310027 Institute of Fluid Mechanics China Jiliang UniversityHangzhou 310018

Nanoparticle distributions in a fully developed turbulent boundary layer are simulated numerically using the moment *** effects of Schmidt number and Damk(o)hler number on the nanoparticle distribution are *** is found that the particle number concentration and total particle mass increase from the wall to the *** difference of particle number concentration and total particle mass near the wall and near the outside becomes smaller with the increasing Schmidt number *** particle diameter and geometric standard deviation increase from the wall to the outside at a fixed Damk(o)hler number Da,and grow with the increase of Da at the same lateral position.

关键词： particle outside Boundary

The limit of the Boussinesq system of Rayleigh-Bénard convection as the Prandtl number approaches infinity

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Applied Mathematics(A Journal of Chinese Universities) 2011年第4期26卷 493-502页

作者： shi jian-guo WU zhong-lin Department of Mathematics Huanghuai University Zhumadian 463000 China

Benard convection is studied by the asymptotic expansion methods of singular perturbation theory and the classical energy methods. For ill-prepared initial data, an exact approximating 1 solution with expansions up to any order are given and the convergence rates O（εm＋1/2）and the optimal convergence rates O（εm＋1） are obtained respectively. This improves the result of J.G. shi.

关键词： Infinite Prandtl number limitl Rayleigh-Benard convection Boussinesq system asymptotic expansions singular perturbation classical energy methods.

Properties of the Collision Efficiency of Nanoparticles in Brownian Coagulation

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Chinese Physics Letters 2011年第1期28卷 130-133页

作者： WANG Yu-Ming LIN jian-zhong chen zhong-Li Institute of Fluid Mechanics China Jiliang University Hangzhou 310018 Department of Mechanics Zhejiang University Hangzhou 310027

The collision efficiency of nanoparticles with diameters from 100nm to 750nm in the Brownian coagulation is studied by building and solving＂ numerically the equations of particle collision in the presence of the van der Waals force, the elastic deformation force, the Stokes resistance, the lubrication force and the electrostatic force. The results show that the collision efficiency decreases overall with the increasing- particle diameter. It is found that there exists an abrupt increase in the collision efficiency when the particle diameter is equals to 550nm. Finally a new expression for the collision efficiency is presented.

关键词： Condensed matter: structural, mechanical & thermal Nanoscale science and low-D systems