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NORMALIZED SOLUTIONS FOR THE GENERAL KIRCHHOFF TYPE EQUATIONS
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作者 Wenmin LIU Xuexiu ZHONG Jinfang ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1886-1902,共17页
In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈ℝ×H^(1)(ℝ^(N))to the general Kirchhoff problem-M\left(\int_{\mathbb{R}^N}\vert\nabla u\ve... In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈ℝ×H^(1)(ℝ^(N))to the general Kirchhoff problem-M\left(\int_{\mathbb{R}^N}\vert\nabla u\vert^2{\rm d}x\right)\Delta u+\lambda u=g(u)~\hbox{in}~\mathbb{R}^N,u\in H^1(\mathbb{R}^N),N\geq 1,satisfying the normalization constraint\int_{\mathbb{R}^N}u^2{\rm d}x=c,where M∈C([0,∞))is a given function satisfying some suitable assumptions.Our argument is not by the classical variational method,but by a global branch approach developed by Jeanjean et al.[J Math Pures Appl,2024,183:44–75]and a direct correspondence,so we can handle in a unified way the nonlinearities g(s),which are either mass subcritical,mass critical or mass supercritical. 展开更多
关键词 normalized solution Kirchhoff type equations general nonlinearities asymptotic behavior
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A Survey Study on TPACK Framework for Normal Students of English Major in Ethnic Colleges and Universities:Empirical Analysis Based on Structural Equation Modeling
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作者 Qinxian Chen Xuanxuan Zhong Xinyi Liu 《Journal of Contemporary Educational Research》 2024年第9期112-119,共8页
With the continuous advancement of education informatization,Technological Pedagogical Content Knowledge(TPACK),as a new theoretical framework,provides a novel method for measuring teachers’informatization teaching a... With the continuous advancement of education informatization,Technological Pedagogical Content Knowledge(TPACK),as a new theoretical framework,provides a novel method for measuring teachers’informatization teaching ability.This study takes normal students of English majors from three ethnic universities as the research object,collects relevant data through questionnaires,and uses structural equation modeling to conduct data analysis and empirical research to investigate the differences in the TPACK levels of these students at different grades and the structural relationships among the elements in the TPACK structure.The technological pedagogical knowledge element of the TPACK structure was not obtained by exploratory factors analysis but through path analysis and structural equation modeling,the results show that the one-dimensional core knowledge of technological knowledge(TK),content knowledge(CK),and pedagogical knowledge(PK)have a positive effect on the two-dimensional interaction knowledge of technological content knowledge(TCK)and pedagogical content knowledge(PCK);furthermore,TCK and PCK have a positive effect on TPACK;and TK,CK,and PK indirectly affect TPACK through TCK and PCK.On this basis,suggestions are provided to ethnic colleges and universities to develop the TPACK knowledge competence of normal students of English majors. 展开更多
关键词 TPACK Ethnic colleges and universities normal students of English major Structural equation modeling
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THE EXISTENCE AND STABILITY OF NORMALIZED SOLUTIONS FOR A BI-HARMONIC NONLINEAR SCHR?DINGER EQUATION WITH MIXED DISPERSION
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作者 罗庭健 郑世骏 朱世辉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期539-563,共25页
In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bu... In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bulk medium with a second-order dispersion term.Denoting by Qpthe ground state for the BNLS withμ=0,we prove that in the mass-subcritical regime p∈(1,1+8/d),there exist orbit ally stable ground state solutions for the BNLS when p∈(-λ0,∞)for someλ0=λ0(p,d,‖Qp‖L2)>0.Moreover,in the mass-critical case p=1+8/d,we prove the orbital stability on a certain mass level below‖Q*‖L2,provided thatμ∈(-λ1,0),where■and Q*=Q1+8/d.The proofs are mainly based on the profile decomposition and a sharp Gagliardo-Nirenberg type inequality.Our treatment allows us to fill the gap concerning the existence of the ground states for the BNLS when p is negative and p∈(1,1+8/d]. 展开更多
关键词 elliptic equations bi-harmonic operator normalized solutions profile decomposition
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High-efciency improved symmetric successive over-relaxation preconditioned conjugate gradient method for solving large-scale finite element linear equations 被引量:1
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作者 李根 唐春安 李连崇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第10期1225-1236,共12页
Fast solving large-scale linear equations in the finite element analysis is a classical subject in computational mechanics. It is a key technique in computer aided engineering (CAE) and computer aided manufacturing ... Fast solving large-scale linear equations in the finite element analysis is a classical subject in computational mechanics. It is a key technique in computer aided engineering (CAE) and computer aided manufacturing (CAM). This paper presents a high-efficiency improved symmetric successive over-relaxation (ISSOR) preconditioned conjugate gradient (PCG) method, which maintains lelism consistent with the original form. Ideally, the by 50% as compared with the original algorithm. the convergence and inherent paralcomputation can It is suitable for be reduced nearly high-performance computing with its inherent basic high-efficiency operations. By comparing with the numerical results, it is shown that the proposed method has the best performance. 展开更多
关键词 improved preconditioned conjugate gradient (PCG) method conjugate gradient method large-scale linear equation finite element method
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STABILITY OF NONLINEAR COMPARISON EQUATIONS FOR DISCRETE LARGE-SCALE SYSTEMS
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作者 舒煌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期779-785,共7页
On the stability analysis of large-scale systems by Lyapunov functions, it is necessary to determine the stability of vector comparison equations. For discrete systems, only the stability of linear autonomous comparis... On the stability analysis of large-scale systems by Lyapunov functions, it is necessary to determine the stability of vector comparison equations. For discrete systems, only the stability of linear autonomous comparison equations was studied in the past. In this paper, various criteria of stability for discrete nonlinear autonomous comparison equations are completely established. Among them, a criterion for asymptotic stability is not only sufficient, but also necessary, from which a criterion on the function class C, is derived. Both of them can be used to determine the unexponential stability, even in the large, for discrete nonlinear (autonomous or nonautonomous) systems. All the criteria are of simple algebraic forms and can be readily used. 展开更多
关键词 STABILITY OF NONLINEAR COMPARISON equatIONS FOR DISCRETE large-scale SYSTEMS
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Normalization of Hydrodynamic Coefficients in Morison Equation 被引量:2
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作者 LI Yucheng Professor, the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, P. R. China. 《China Ocean Engineering》 SCIE EI 1999年第2期125-132,共8页
The hydrodynamic coefficients C-d and C-m are not only dependent on the size of slender cylinder, its location in water, KC number and Re number, but also vary with environmental conditions, i.e., in regular waves or ... The hydrodynamic coefficients C-d and C-m are not only dependent on the size of slender cylinder, its location in water, KC number and Re number, but also vary with environmental conditions, i.e., in regular waves or in irregular waves, in pure waves or in wave-current coexisting field. In this paper, the normalization of hydrodynamic coefficients for various environmental conditions is discussed. When a proper definition of KC number and proper characteristic values of irregular waves are used, a unified relationship between C-d, C-m and KC number for regular waves, irregular waves, pure waves and wave-current coexisting field can be obtained. 展开更多
关键词 Morison equation drag force coefficient inertia force coefficient hydrodynamic coefficient normalIZATION
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TO SOLVE MATRIX EQUATION sum (A^iXBi=c) BY THE SMITH NORMAL FORM
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作者 Huang LipingInstitute of Mathematics and Software, Xiangtan Polytechnic University, Xiangtan 411201. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期109-118,共10页
By using the Smith normal form of polynomial matrix and algebraic methods, this paper discusses the solvability for the linear matrix equation A iXB i=C over a field, and obtains the explicit formulas of general sol... By using the Smith normal form of polynomial matrix and algebraic methods, this paper discusses the solvability for the linear matrix equation A iXB i=C over a field, and obtains the explicit formulas of general solution or unique solution. 展开更多
关键词 matrix equation Smith normal form universally solvable g-inverse.
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SOLUTIONS TO A CLASS OF PARABOLIC INHOMOGENEOUS NORMALIZED p-LAPLACE EQUATIONS
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作者 刘芳 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期477-494,共18页
In this article, we prove that viscosity solutions of the parabolic inhomogeneous equationsn+p/put-△p^Nu=f(x,t)can be characterized using asymptotic mean value properties for all p ≥ 1, including p = 1 and p = ∞... In this article, we prove that viscosity solutions of the parabolic inhomogeneous equationsn+p/put-△p^Nu=f(x,t)can be characterized using asymptotic mean value properties for all p ≥ 1, including p = 1 and p = ∞. We also obtain a comparison principle for the non-negative or non-positive inhomogeneous term f for the corresponding initial-boundary value problem and this in turn implies the uniqueness of solutions to such a problem. 展开更多
关键词 Parabolic normalized p-Laplace equation viscosity solution asymptotic mean value property comparison principle uniqueness theorem infinity Laplacian
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On Finding Geodesic Equation of Normal Distribution and Gaussian Curvature
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作者 William W. S. Chen 《Applied Mathematics》 2017年第9期1336-1342,共7页
In this paper, we apply two different algorithms to find the geodesic equation of the normal distribution. The first algorithm consists of solving a triply partial differential equation where these equations originate... In this paper, we apply two different algorithms to find the geodesic equation of the normal distribution. The first algorithm consists of solving a triply partial differential equation where these equations originated from the normal distribution. While the second algorithm applies the well-known Darboux Theory. These two algorithms draw the same geodesic equation. Finally, we applied Baltzer R.’s finding to compute the Gaussian Curvature. 展开更多
关键词 DARBOUX Theory DIFFERENTIAL Geometry GEODESIC equatION PARTIAL DIFFERENTIAL equatION normal Distribution
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A Principal Theorem of Normal Discretization Schemes for Operator Equations of the First Kind
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作者 Du Nai lin 1, Wang Hannah 2 1.School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China 2. School of Foreign Languages and Literature,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第4期767-768,共2页
The authors announce a newly-proved theorem of theirs. This theorem is of principal significance to numerical computation of operator equations of the first kind.
关键词 operator equation of the first kind normal discretization scheme pure pseudoinverse
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Assessments of Some Simultaneous Equation Estimation Techniques with Normally and Uniformly Distributed Exogenous Variables
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作者 O. O. Alabi B. A. Oyejola 《Applied Mathematics》 2015年第11期1902-1912,共11页
In each equation of simultaneous Equation model, the exogenous variables need to satisfy all the basic assumptions of linear regression model and be non-negative especially in econometric studies. This study examines ... In each equation of simultaneous Equation model, the exogenous variables need to satisfy all the basic assumptions of linear regression model and be non-negative especially in econometric studies. This study examines the performances of the Ordinary Least Square (OLS), Two Stage Least Square (2SLS), Three Stage Least Square (3SLS) and Full Information Maximum Likelihood (FIML) Estimators of simultaneous equation model with both normally and uniformly distributed exogenous variables under different identification status of simultaneous equation model when there is no correlation of any form in the model. Four structural equation models were formed such that the first and third are exact identified while the second and fourth are over identified equations. Monte Carlo experiments conducted 5000 times at different levels of sample size (n = 10, 20, 30, 50, 100, 250 and 500) were used as criteria to compare the estimators. Result shows that OLS estimator is best in the exact identified equation except with normally distributed exogenous variables when . At these instances, 2SLS estimator is best. In over identified equations, the 2SLS estimator is best except with normally distributed exogenous variables when the sample size is small and large, and;and with uniformly distributed exogenous variables when n is very large, , the best estimator is either OLS or FIML or 3SLS. 展开更多
关键词 normally DISTRIBUTED EXOGENOUS VARIABLES UNIFORMLY DISTRIBUTED EXOGENOUS VARIABLES Identification Status ESTIMATORS Exact Identified equatION Over Identified equatION
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STUDYING THE FOCAL VALUE OF ORDINARY DIFFERENTIAL EQUATIONS BY NORMAL FORM THEORY
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作者 张琪昌 梁以德 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第9期891-900,共10页
We present a new method to calculate the focal value of ordinary differential equation by applying the theorem defined the relationship between the normal form and focal value,with the help of a symbolic computation l... We present a new method to calculate the focal value of ordinary differential equation by applying the theorem defined the relationship between the normal form and focal value,with the help of a symbolic computation language M ATHEMATICA,and extending the matrix representation method.This method can be used to calculate the focal value of any high order terms.This method has been verified by an example.The advantage of this method is simple and more readily applicable.the result is directly obtained by substitution. 展开更多
关键词 normal form ordinary differential equation focal value MATHEMATICA
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Application of Neurocomputing in Adaptive Control of Large-Scale Aerospace Systems
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作者 Lu Zhao & Lu He(Department of Electrical & Computer Engineering University of Houston, USA Department of Automation, Tianjin Institute of Technology, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第4期61-65,共5页
We are engaged in solving two difficult problems in adaptive control of the large-scale time-variant aerospace system. One is parameter identification of time-variant continuous-time state-space modei; the other is ho... We are engaged in solving two difficult problems in adaptive control of the large-scale time-variant aerospace system. One is parameter identification of time-variant continuous-time state-space modei; the other is how to solve algebraic Riccati equation (ARE) of large order efficiently. In our approach, two neural networks are employed to independently solve both the system identification problem and the ARE associated with the optimal control problem. Thus the identification and the control computation are combined in closed-loop, adaptive, real-time control system . The advantage of this approach is that the neural networks converge to their solutions very quickly and simultaneously. 展开更多
关键词 large-scale system System identification Hopfield neural network Algebraic Riccati equation Recurrent neural network.
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Normalized fatigue properties of asphalt mixture at various temperatures 被引量:2
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作者 Dongdong Ge Zihao Ju +3 位作者 Defeng Duan Songtao Lyu Weiwei Lu Chaochao Liu 《Journal of Road Engineering》 2023年第3期279-287,共9页
This study normalized the mixture's fatigue behavior at various temperatures,and the strength and fatigue tests of the mixture were conducted.The stress state of the asphalt mixture includes direct tensile,uniaxia... This study normalized the mixture's fatigue behavior at various temperatures,and the strength and fatigue tests of the mixture were conducted.The stress state of the asphalt mixture includes direct tensile,uniaxial compression,and indirect tensile.The Desai yield surface and fatigue path were proposed.And a normalized fatigue characteristics model of the mixture was established.The following conclusions were obtained.With the increases in the loading rate,the strength of the asphalt mixture increased.As the temperature increases,the strength of the mixture is reduced.At various temperatures and rates,the strength forms a closed curved surface.The Desai strength yield surface was established,which forms a closed curved surface.When the loading rate and temperature are below a certain critical line,the asphalt mixture will not undergo strength damage.At a fixed stress state,the fatigue damage path of the mixture was determined.The stress ratio was determined considering the influence of the loading rate.In this way,a normalized model can be described to express the asphalt mixture fatigue properties at various temperatures and stress levels.For the asphalt mixture in an indirect tensile state,the normalized fatigue equation parameter is 4.09.This model is more suitable for reflecting the viscous-elastic behavior of the mixtures than the fatigue equation determined by the notional stress ratio. 展开更多
关键词 Asphalt mixture normalization equation Load rates Test temperature Stress level Desai yield surface
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Factorized Smith Method for A Class of High-Ranked Large-Scale T-Stein Equations
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作者 LI Xiang YU Bo TANG Qiong 《Chinese Quarterly Journal of Mathematics》 2024年第3期235-249,共15页
We introduce a factorized Smith method(FSM)for solving large-scale highranked T-Stein equations within the banded-plus-low-rank structure framework.To effectively reduce both computational complexity and storage requi... We introduce a factorized Smith method(FSM)for solving large-scale highranked T-Stein equations within the banded-plus-low-rank structure framework.To effectively reduce both computational complexity and storage requirements,we develop techniques including deflation and shift,partial truncation and compression,as well as redesign the residual computation and termination condition.Numerical examples demonstrate that the FSM outperforms the Smith method implemented with a hierarchical HODLR structured toolkit in terms of CPU time. 展开更多
关键词 large-scale T-Stein equations High-ranked Deflation and shift Partially truncation and compression Smith method
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A normalized wavefield separation cross-correlation imaging condition for reverse time migration based on Poynting vector 被引量:15
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作者 陈婷 何兵寿 《Applied Geophysics》 SCIE CSCD 2014年第2期158-166,253,共10页
Prestack reverse time migration(PSTM) is a common imaging method; however low-frequency noises reduce the structural imaging precision. Thus, the suppression of migration noises must be considered. The generation me... Prestack reverse time migration(PSTM) is a common imaging method; however low-frequency noises reduce the structural imaging precision. Thus, the suppression of migration noises must be considered. The generation mechanism of low-frequency noises is analyzed and the up-, down-, left-, and right-going waves are separated using the Poynting vector of the acoustic wave equation. The computational complexity and memory capacitance of the proposed method are far smaller than that required when using the conventional separation algorithm of 2D Fourier transform. The normalized wavefield separation crosscorrelation imaging condition is used to suppress low-frequency noises in reverse time migration and improve the imaging precision. Numerical experiments using the Marmousi model are performed and the results show that the up-, down-, left-, and right-going waves are well separated in the continuation of the wavefield using the Poynting vector. We compared the imaging results with the conventional method, Laplacian filtering, and wavefield separation with the 2D Fourier transform. The comparison shows that the migration noises are well suppressed using the normalized wavefield separation cross-correlation imaging condition and higher precision imaging results are obtained. 展开更多
关键词 acoustic wave equation Poynting vector wavefield separation normalized crosscorrelation migration noises
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基于双调和插值的锥束CT金属伪影校正算法
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作者 王中昊 夏竟 +1 位作者 李世杰 蔡志平 《计算机工程与科学》 CSCD 北大核心 2024年第3期471-478,共8页
在计算机断层扫描(CT)中,金属植入物会引入严重的伪影,导致图像质量降低影响诊断价值。为了对锥束CT中的金属伪影进行校正,提出了一种基于双调和方程的金属伪影校正算法。首先,对含金属伪影的重建图像进行双边滤波和金属阈值分割,获得... 在计算机断层扫描(CT)中,金属植入物会引入严重的伪影,导致图像质量降低影响诊断价值。为了对锥束CT中的金属伪影进行校正,提出了一种基于双调和方程的金属伪影校正算法。首先,对含金属伪影的重建图像进行双边滤波和金属阈值分割,获得金属和非金属图像;然后,对二者进行正向投影,获得金属投影区域和先验投影图像;接下来,利用先验投影图像对原始投影进行归一化,并对金属区域进行双调和方程插值修复,获得修复的投影数据;最后,对修复的投影数据去归一化,并利用FDK算法进行重建,再与金属图像融合获得最终的校正图像。为了验证该算法的性能,采用实际拍摄的数据进行金属伪影校正实验。结果表明,与常用的线性插值校正算法和归一化校正算法相比,所提算法ROI区域内图像的均方根误差分别减少了22%和8%,有效地抑制了金属伪影,优于常用的去金属伪影算法。 展开更多
关键词 锥束CT 金属伪影校正 双调和插值 修复 归一化校正
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Kirchhoff型方程正规化解的多重性及渐近行为
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作者 靳振峰 孙红蕊 张为民 《数学物理学报(A辑)》 CSCD 北大核心 2024年第4期871-884,共14页
该文研究了如下Kirchhoff型方程{−(a+b∫R^(3)|∇u|^(2)dx)Δu=λu+|u|^(p−2)u,x∈R^(3),∥u∥22=ρ,其中a,b,ρ>0,λ∈R是与质量约束∥u∥22=ρ有关的Lagrange乘子.当p∈(2,103)或者p∈(143,6)时,利用亏格理论证明了上述方程L2-正规... 该文研究了如下Kirchhoff型方程{−(a+b∫R^(3)|∇u|^(2)dx)Δu=λu+|u|^(p−2)u,x∈R^(3),∥u∥22=ρ,其中a,b,ρ>0,λ∈R是与质量约束∥u∥22=ρ有关的Lagrange乘子.当p∈(2,103)或者p∈(143,6)时,利用亏格理论证明了上述方程L2-正规化解的多重性.此外,该文证明了上述解关于参数b→0^(+)时的渐近行为. 展开更多
关键词 KIRCHHOFF方程 变分法 正规化解 渐近行为
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考虑材料应变率效应的冲击响应模型相似律研究
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作者 王傲寒 王帅 李继承 《装备环境工程》 CAS 2024年第4期55-61,共7页
目的研究考虑材料应变率效应的冲击响应模型相似律,获得一个能够综合材料弹塑性和应变率效应的精确相似解,支撑工程领域的模型试验。方法根据BuckinghamП定理,综合考虑材料的弹性、应变硬化和应变率效应,进一步推导了工程结构在冲击响... 目的研究考虑材料应变率效应的冲击响应模型相似律,获得一个能够综合材料弹塑性和应变率效应的精确相似解,支撑工程领域的模型试验。方法根据BuckinghamП定理,综合考虑材料的弹性、应变硬化和应变率效应,进一步推导了工程结构在冲击响应的模型相似律表达式。在此基础上,提出改变结构质量和冲击器速度来满足模型相似律的方法。结果相比最近冲击模型相似律的研究中存在近似相似、迭代求解的缺陷,该方法是一个显式、完全精确的相似解,并且能够同时考虑材料的弹性、应变硬化和应变率效应。采用圆板撞击的有限元数值模型进行了验证。结论推导出的模型相似律能够准确地预测原型的动态冲击的响应。相比而言,使用以往的相似方法具有明显的误差。 展开更多
关键词 应变率 模型相似律 相似 缩比 冲击 模化方程
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Normalized Solution for p-Kirchhoff Equation with a L2-supercritical Growth
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作者 Zhi-min REN Yong-yi LAN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第2期414-429,共16页
In this paper,we investigate the following p-Kirchhoff equation{∫R^(N)|u|^(2)dx=ρ,(a+b)∫RN(|Δu}^(p)+|u|^(p))dx)(-Δpu+|u|^(p-2u)=|u|^(s-2)u+μu,x∈R^(N),where a>0,b≥0,p>0 are constants,constants,p*=N-P/Np i... In this paper,we investigate the following p-Kirchhoff equation{∫R^(N)|u|^(2)dx=ρ,(a+b)∫RN(|Δu}^(p)+|u|^(p))dx)(-Δpu+|u|^(p-2u)=|u|^(s-2)u+μu,x∈R^(N),where a>0,b≥0,p>0 are constants,constants,p*=N-P/Np is the critical Sobolev exponent,μis a Lagrange multiplier,-Δpu=-div(|Δu|_(p-2)u),2<p<N2p,μ∈R,and s∈(2N/N+2p-2,p*).We demonstratethat he p-Kirchhoff equation has a normalized solution using the mountain pass lemma and some analysis techniques. 展开更多
关键词 p-Kirchhoff equation normalized solution mountain-pass lemma
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