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Journal of Computational Mathematics 2024年第2期42卷 544-569页

作者： changhui yao Fengdan Zhang Cheng Wang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Department of Mathematics University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we consider the Cahn-Hilliard-Hele-Shaw(CHHS)system with the dynamic boundary conditions,in which both the bulk and surface energy parts play important *** scalar auxiliary variable approach is introduced for the physical system;the mass conservation and energy dissipation is proved for the CHHS ***,a fully discrete SAV finite element scheme is proposed,with the mass conservation and energy dissipation laws established at a theoretical *** addition,the convergence analysis and error estimate is provided for the proposed SAV numerical scheme.

关键词： Cahn-Hilliard-Hele-Shaw system Dynamic boundary conditions Bulk energy and surface energy Scalar auxiliary variable formulation Energy stability Convergence analysis

Unconditional Superconvergence Analysis of Energy Conserving Finite Element Methods for the Nonlinear Coupled Klein-Gordon Equations

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Advances in Applied Mathematics and Mechanics 2023年第3期15卷 602-622页

作者： Ming Cui Yanfei Li changhui yao Faculty of Science Beijing University of TechnologyBeijing 1000124China School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China

In this paper,we consider the energy conserving numerical scheme for coupled nonlinear Klein-Gordon *** propose energy conserving finite element method and get the unconditional superconvergence resultO(h^(2)+Dt^(2))by using the error splitting technique and postprocessing *** experiments are carried out to support our theoretical results.

关键词： Energy conserving the nonlinear coupled Klein-Gordon equations unconditional superconvergence result postprocessing interpolation finite element method

SAV Finite Element Method for the Peng-Robinson Equation of State with Dynamic Boundary Conditions

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Advances in Applied Mathematics and Mechanics 2023年第1期15卷 139-158页

作者： changhui yao Zhaoyue Du Lei Yang School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China Faculty of Information Technology Macao University of Science and TechnologyMacao

In this paper,the Peng-Robinson equation of state with dynamic boundary conditions is discussed,which considers the interactions with solid *** first,the model is introduced and the regularization method on the nonlinear term is ***,The scalar auxiliary variable(SAV)method in temporal and finite element method in spatial are used to handle the Peng-Robinson equation of ***,the energy dissipation law of the numerical method is ***,we acquire the convergence of the discrete SAV finite element method(FEM).Finally,a numerical example is provided to confirm the theoretical result.

关键词： Peng-Robinson equation of state dynamic boundary conditions scalar auxiliary variable finite element method error estimates

Nonconforming Mixed FEM Analysis for Multi-Term Time-Fractional Mixed Sub-Diffusion and Diffusion-Wave Equation with Time-Space Coupled Derivative

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Advances in Applied Mathematics and Mechanics 2023年第2期15卷 322-358页

作者： Fangfang Cao Yanmin Zhao Fenling Wang Yanhua Shi changhui yao School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China School of Science Xuchang UniversityXuchangHenan 461000China Henan Joint International Research Laboratory of High Performance Computation for Complex Systems XuchangHenan 461000China

The main contents of this paper are to establish a finite element fully-discrete approximate scheme for multi-term time-fractional mixed sub-diffusion and diffusionwave equation with spatial variable coefficient,which contains a time-space coupled *** nonconforming EQ^(rot)_(1)element and Raviart-Thomas element are employed for spatial discretization,and L1 time-stepping method combined with the Crank-Nicolson scheme are applied for temporal ***,based on some significant lemmas,the unconditional stability analysis of the fully-discrete scheme is *** the assistance of the interpolation operator I_(h)and projection operator Rh,superclose and convergence results of the variable u in H^(1)-norm and the flux~p=k_(5)(x)ru(x,t)in L^(2)-norm are obtained,***,the global superconvergence results are derived by applying the interpolation postprocessing ***,the availability and accuracy of the theoretical analysis are corroborated by experimental results of numerical examples on anisotropic meshes.

关键词： Multi-term time-fractional mixed sub-diffusion and diffusion-wave equation nonconforming EQ^(rot)_(1)mixed FEM L1 approximation and Crank-Nicolson scheme convergence and superconvergence

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化工行业碳排放核算及影响因素

化工管理 2024年第20期 96-99页

作者：么长慧马朝君冯早彭巨擘云南锡业集团(控股)有限责任公司研发中心云南昆明650200 昆明理工大学信息工程与自动化学院云南昆明650500

“双碳”政策提出后,管理温室气体的排放已成为当前学术界研究的焦点。目前,温室气体排放问题较为突出,越来越多地关注集中在了减排降碳的重点产业。确定化工行业的核算边界是开展化工行业碳排放研究的前提,然而当前的相关研究在划分的... 详细信息

“双碳”政策提出后,管理温室气体的排放已成为当前学术界研究的焦点。目前,温室气体排放问题较为突出,越来越多地关注集中在了减排降碳的重点产业。确定化工行业的核算边界是开展化工行业碳排放研究的前提,然而当前的相关研究在划分的标准上有出入,缺乏一致性的规范,导致各研究案例之间缺少可比性。为了给化工企业节约能源减少碳排放的研究提供参考,文章重点介绍了化工行业碳排放核算方法的主要特点及研究现状,并分析了三类主要方法的优缺点及其应用情况,重点研究了工业领域和化工行业的驱动影响因素,从化工企业碳排放的核算方法、影响因素等方面指出了现有研究的不足之处。

关键词：化工行业碳排放影响因素核算方法

基于灰狼优化支持向量机回归与SHAP值的锡冶炼能耗预测

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有色金属（冶炼部分） 2024年第2期 1-7页

作者：马朝君彭巨擘袁海滨郑光发么长慧章夏冰冯早云南锡业集团(控股)有限责任公司研发中心昆明650200 昆明理工大学信息工程与自动化学院昆明650500

锡冶炼过程综合能源消耗占整个锡生产过程90%,存在很大节能潜力。针对锡冶炼过程综合能耗机理模型难以建立、导致预测准确度不高的问题,提出灰狼优化的支持向量机回归(GWO-SVR)模型用于锡冶炼过程综合能耗的预测,并以某锡冶炼厂为例,将... 详细信息

锡冶炼过程综合能源消耗占整个锡生产过程90%,存在很大节能潜力。针对锡冶炼过程综合能耗机理模型难以建立、导致预测准确度不高的问题,提出灰狼优化的支持向量机回归(GWO-SVR)模型用于锡冶炼过程综合能耗的预测,并以某锡冶炼厂为例,将所提模型与SVR、RF(随机森林)、BP(反向传播神经网络)、LR(线性回归)模型进行比较。结果表明,GWO-SVR模型可获得最理想的预测结果,在预测精度上相比于其他机器学习算法有着巨大优势。此外,使用SHAP值从全局解释和单样本解释两个方面解释所建立的GWO-SVR模型,可视化特征对输出的贡献,增加了GWO-SVR的可解释性,并以此制定可靠的节能策略。

关键词：锡冶炼预测模型模型可解释性支持向量机回归灰狼优化算法

Binary Level Set Methods for Dynamic Reservoir Characterization by Operator Splitting Scheme

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Advances in Applied Mathematics and Mechanics 2012年第6期4卷 780-798页

作者： changhui yao Department of Mathematics Zhengzhou UniversityNo.100 of Science RoadZhengzhou 450001HenanChina

In this paper,operator splitting scheme for dynamic reservoir characterization by binary level set method is *** this problem,the absolute permeability of the two-phase porous medium flow can be simulated by the constrained augmented Lagrangian optimization method with well data and seismic time-lapse *** transforming the constrained optimization problem in an unconstrained one,the saddle point problem can be solved by Uzawas algorithms with operator splitting scheme,which is based on the essence of binary level set *** the simple and complicated numerical examples demonstrate that the given algorithms are stable and efficient and the absolute permeability can be satisfactorily recovered.

关键词： Dynamic reservoir characterization binary level set method operator splitting scheme the augmented lagrangian method

Nonconforming Finite Element Methods for Wave Propagation in Metamaterials

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Numerical Mathematics(Theory,Methods and Applications) 2017年第1期10卷 145-166页

作者： changhui yao Lixiu Wang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou450001P.R.China Beijing ComputationalScience Research Center Beijing100193P.R.China

In this paper,nonconforming mixed finite element method is proposed to simulate the wave propagation in *** error estimate of the semi-discrete scheme is given by convergence order O(h 2),which is less than 40 percent of the computational costs comparing with the same effect by using Nédélec-Raviart element.A Crank-Nicolson full discrete scheme is also presented with O(τ2+h 2)by traditional discrete formula without using penalty *** examples of 2D TE,TM cases and a famous re-focusing phenomena are shown to verify our theories.

关键词： Wave Propagation Metamaterials Nonconforming Mixed Finite Element Error Estimates

A Confined Two-peaked Solar Flare Observed by EAST and SDO

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Research in Astronomy and Astrophysics 2024年第4期24卷 71-83页

作者： Liang Zhang Ruisheng Zheng Zhike Xue changhui Rao Qing Lin Zhimao Du Jiawen yao Libo Zhong yao Chen Institute of Space Sciences Shandong UniversityWeihai 264209China Yunnan Key Laboratory of the Solar physics and Space Science Kunming 650011China Institute of Frontier and Interdisciplinary Science.Shandong University Qingdao266237China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China National Laboratory on Adaptive Optics Chengdu610209China University of Chinese Academy of Sciences Beijing 100049China Shanghai Astronomy Museum Shanghai201306China

The solar flare is one of the most violent explosions,and can disturb the near-Earth space *** for commonly single-peaked solar flares in soft X-ray,some special flares show intriguing a two-peak feature that is deserved much more ***,we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics *** the flare,a magnetic flux rope(MFR)formed through partially tether-cutting reconnection between two sheared *** flare occurred after the MFR eruption that was confined by the overlying strong ***,a small underlying filament immediately erupted,which was possibly destabilized by the flare *** successive eruptions were confirmed by the analysis of the emission measure and the reconnection ***,we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.

关键词： Sun:activity Sun:corona Sun:flares Sun:magnetic fields Sun:filaments prominences Online material:animations

Extrapolation of Mixed Finite Element Approximations for the Maxwell Eigenvalue Problem

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Numerical Mathematics(Theory,Methods and Applications) 2011年第3期4卷 379-395页

作者： changhui yao Zhonghua Qiao Department of Mathematics Zhengzhou UniversityZhengzhouChina Institute for Computational Mathematics&Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong.

In this paper,a general method to derive asymptotic error expansion formulas for the mixed finite element approximations of the Maxwell eigenvalue problem is *** lemmas for the error of the eigenvalue approximations are ob*** on the asymptotic error expansion formulas,the Richardson extrapolation method is employed to improve the accuracy of the approximations for the eigenvalues of the Maxwell system from O(h2)to O(h4)when applying the lowest order Nédélec mixed finite element and a nonconforming mixed finite *** our best knowledge,this is the first superconvergence result of the Maxwell eigenvalue problem by the extrapolation of the mixed finite element *** experiments are provided to demonstrate the theoretical results.

关键词： Maxwell eigenvalue problem mixed finite element asymptotic error expansion Richardson extrapolation.