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Path integral solutions for n-dimensional stochastic differential equations underα-stable Lévy excitation
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作者 Wanrong Zan Yong Xu Jürgen Kurths 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第2期98-112,共15页
In this paper,the path integral solutions for a general n-dimensional stochastic differential equa-tions(SDEs)withα-stable Lévy noise are derived and verified.Firstly,the governing equations for the solutions of... In this paper,the path integral solutions for a general n-dimensional stochastic differential equa-tions(SDEs)withα-stable Lévy noise are derived and verified.Firstly,the governing equations for the solutions of n-dimensional SDEs under the excitation ofα-stable Lévy noise are obtained through the characteristic function of stochastic processes.Then,the short-time transition probability density func-tion of the path integral solution is derived based on the Chapman-Kolmogorov-Smoluchowski(CKS)equation and the characteristic function,and its correctness is demonstrated by proving that it satis-fies the governing equation of the solution of the SDE,which is also called the Fokker-Planck-Kolmogorov equation.Besides,illustrative examples are numerically considered for highlighting the feasibility of the proposed path integral method,and the pertinent Monte Carlo solution is also calculated to show its correctness and effectiveness. 展开更多
关键词 Path integral method α-stable Lévy noise Monte carlo method Fokker-Planck-Kolmogorov equation
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Verification of the Landau Equation and Hardy’s Inequality
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作者 Salih Yousuf Mohamed Salih 《Applied Mathematics》 2023年第3期208-229,共22页
We prove the L estimate for the isotropic version of the homogeneous landau problem, which was explored by M. Gualdani and N. Guillen. As shown in a region of the smooth potentials range under values of the interactio... We prove the L estimate for the isotropic version of the homogeneous landau problem, which was explored by M. Gualdani and N. Guillen. As shown in a region of the smooth potentials range under values of the interaction exponent (2), a weighted Poincaré inequality is a natural consequence of the traditional weighted Hardy inequality, which in turn implies that the norms of solutions propagate in the L1 space. Now, the L estimate is based on the work of De Giorgi, Nash, and Moser, as well as a few weighted Sobolev inequalities. 展开更多
关键词 Hardy’s Inequality Sobolev Inequalities the Landau equation L-Estimate
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基于Maxwell方程和R-L分数阶导数的高频激励条件下纳米晶材料磁滞特性预测模型 被引量:1
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作者 姬俊安 赵志刚 +3 位作者 张时 杜振斌 翟志强 贾慧杰 《中国电机工程学报》 EI CSCD 北大核心 2024年第13期5431-5440,I0035,共11页
准确预测高频激励条件下纳米晶材料的磁滞特性,对电力电子变压器等高频电力设备磁性元件的优化设计具有重要意义。该文基于Maxwell方程和Riemann-Liouville(R-L)分数阶导数,建立高频激励下纳米晶材料磁滞特性预测模型。首先,根据Maxwel... 准确预测高频激励条件下纳米晶材料的磁滞特性,对电力电子变压器等高频电力设备磁性元件的优化设计具有重要意义。该文基于Maxwell方程和Riemann-Liouville(R-L)分数阶导数,建立高频激励下纳米晶材料磁滞特性预测模型。首先,根据Maxwell方程,首次推导出计及趋肤效应影响的涡流磁场强度解析式;其次,针对现有静态磁滞特性和异常效应建模方法未考虑趋肤效应影响的问题,依据R-L型分数阶导数理论,建立有效描述带材内部磁通密度分布不均时纳米晶静态磁滞特性与异常效应综合预测模型,并提出一种考虑频率效应的阻尼系数ρ和非整数阶n的解析计算方法;最后,基于磁场分离理论,建立高频激励下纳米晶材料磁滞特性预测模型。通过与纳米晶材料1K107B在高频激励下实测磁滞回线进行对比,验证该文所建预测模型的有效性。相较于经典模型,该文所建模型对磁滞回线的预测精度提升了35.8%。 展开更多
关键词 MAXWELL方程 Riemann-Liouville(R-L)分数阶导数 趋肤效应 磁滞回线
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线性Poisson-Boltzmann方程的虚单元L^(2)误差估计
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作者 陈键铧 李倩 阳莺 《应用数学》 北大核心 2024年第3期699-705,共7页
针对一类线性Poisson-Boltzmann方程的虚单元L^(2)误差估计进行分析.首先引入正则化的线性Poisson-Boltzmann方程,将原问题转化为非奇性Poisson-Boltzmann方程.然后给出L^(2)范数的误差估计.最后在四边形和五边形混合多边形网格上进行... 针对一类线性Poisson-Boltzmann方程的虚单元L^(2)误差估计进行分析.首先引入正则化的线性Poisson-Boltzmann方程,将原问题转化为非奇性Poisson-Boltzmann方程.然后给出L^(2)范数的误差估计.最后在四边形和五边形混合多边形网格上进行数值实验,数值结果验证了理论分析的正确性. 展开更多
关键词 POISSON-BOLTZMANN方程 虚单元法 L 2误差估计 混合多边形网格
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2维薛定谔方程的一种高精度紧致差分格式
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作者 依力米努尔·尼扎木 开依沙尔·热合曼 《江西师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期189-193,共5页
该文对2维薛定谔方程利用局部一维化方法,将2维方程分裂为x、y方向的2个1维薛定谔方程,然后采用6阶紧致格式的离散方法来处理空间变量的2阶导数项,将薛定谔方程转化为一个常微分方程组.通过L-稳定Simpson方法对上述空间离散化得到的常... 该文对2维薛定谔方程利用局部一维化方法,将2维方程分裂为x、y方向的2个1维薛定谔方程,然后采用6阶紧致格式的离散方法来处理空间变量的2阶导数项,将薛定谔方程转化为一个常微分方程组.通过L-稳定Simpson方法对上述空间离散化得到的常微分方程进行离散化,得到了一种具有空间6阶精度和时间3阶精度的格式,并证明了该格式无条件稳定性.并通过数值模拟和对比方法验证了格式的有效性. 展开更多
关键词 2维薛定谔方程 高精度紧致差分格式 局部1维化方法 L-稳定Simpson方法
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一类漂移系数分段连续的随机微分方程驯服Euler方法的L^(p)收敛率
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作者 胡慧敏 甘四清 《数学理论与应用》 2024年第2期1-19,共19页
本文研究一类漂移系数分段连续的标量随机微分方程的驯服Euler方法的L^(p)收敛率.更确切地说,本文在漂移系数是分段连续的并且呈多项式增长,扩散系数是Lipschitz连续的并且在漂移系数的间断点处不为0的假设下,证明方程具有唯一的强解,... 本文研究一类漂移系数分段连续的标量随机微分方程的驯服Euler方法的L^(p)收敛率.更确切地说,本文在漂移系数是分段连续的并且呈多项式增长,扩散系数是Lipschitz连续的并且在漂移系数的间断点处不为0的假设下,证明方程具有唯一的强解,并且对于任意的p∈[1,∞),驯服Euler方法的L^(p)收敛阶都可以达到1/2.此外,本文还提供一个数值算例来验证理论结果. 展开更多
关键词 随机微分方程 漂移系数 驯服Euler方法 L^(p)收敛率
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2维带色散4阶扩散方程的高精度紧致格式
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作者 王红玉 李冉冉 开依沙尔·热合曼 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第4期27-35,共9页
针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解... 针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解常微分方程组的L-稳定的Simpson方法构造时间3阶、空间6阶精度的数值格式,并证明该格式是绝对稳定的.通过数值实验和比较,验证论文格式的有效性. 展开更多
关键词 2维带色散4阶扩散方程 高精度紧致差分格式 CRANK-NICOLSON格式 局部1维化方法 L-稳定Simpson格式
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一类含时Poisson-Nernst-Planck方程的虚单元计算
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作者 刘亚 阳莺 《桂林电子科技大学学报》 2024年第1期1-6,共6页
针对一类含时Poisson-Nernst-Planck(PNP)方程,为避免在解决实际问题时有限元法中的网格适应性问题,构造了L^(2)投影算子与Gummel迭代相结合的虚单元算法。该算法允许以更简单的方式设计和分析新的格式,可以灵活处理各种网格,对于多边... 针对一类含时Poisson-Nernst-Planck(PNP)方程,为避免在解决实际问题时有限元法中的网格适应性问题,构造了L^(2)投影算子与Gummel迭代相结合的虚单元算法。该算法允许以更简单的方式设计和分析新的格式,可以灵活处理各种网格,对于多边形或多面体单元甚至非凸单元组成的网格剖分都可以很好地处理,使得虚单元法可以适应于任意多边形网格,大大降低了网格的生成难度。给出了虚单元算法在三角形网格、四边形网格、非凸网格下的数值算例。数值实验结果表明,在这3种多边形网格上,L^(2)和H^(1)模的收敛阶分别为二阶和一阶,均达到了最优阶。 展开更多
关键词 Poisson-Nernst-Planck方程 虚单元算法 L^(2)投影 Gummel迭代 L^(2)模 H^(1)模
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一类拟线性Schrodinger方程L^(2)约束解的多重性
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作者 彭玉碧 杨先勇 《云南师范大学学报(自然科学版)》 2024年第1期17-22,共6页
通过一个新的形变引理,研究了如下拟线性Schrodinger方程在2<p<4时L^(2)约束解的多重性.-Δu+μu-Δu^(2)u=u^(p-2)u,x∈ℝ^(3),∫_(ℝ^(3))u^(2)d x=m;其中m>0是给定的常数,μ∈ℝ是Lagrange乘子.
关键词 拟线性方程 L^(2)约束解的多重性 新的形变理论
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Singular and non-topological soliton solutions for nonlinear fractional differential equations 被引量:4
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作者 Ozkan Guner 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期10-15,共6页
In this article, the fractional derivatives are described in the modified Riemann-Liouville sense. We propose a new approach, namely an ansatz method, for solving fractional differential equations(FDEs) based on a f... In this article, the fractional derivatives are described in the modified Riemann-Liouville sense. We propose a new approach, namely an ansatz method, for solving fractional differential equations(FDEs) based on a fractional complex transform and apply it to solve nonlinear space-time fractional equations. As a result, the non-topological as well as the singular soliton solutions are obtained. This method can be suitable and more powerful for solving other kinds of nonlinear fractional FDEs arising in mathematical physics. 展开更多
关键词 SOLITONS ansatz method the space-time fractional Boussinesq equation the space-time fractional(2+l)-dimensional breaking soliton equations
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THE HOMOGENEOUS DIRICHLET PROBLEM FOR QUASILINEAR ANISOTROPIC DEGENERATE PARABOLIC-HYPERBOLIC EQUATION WITH L^p INITIAL VALUE 被引量:1
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作者 王志刚 李亚纯 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1727-1742,共16页
The aim of this paper is to prove the well-posedness(existence and uniqueness) of the L p entropy solution to the homogeneous Dirichlet problems for the anisotropic degenerate parabolic-hyperbolic equations with L p... The aim of this paper is to prove the well-posedness(existence and uniqueness) of the L p entropy solution to the homogeneous Dirichlet problems for the anisotropic degenerate parabolic-hyperbolic equations with L p initial value.We use the device of doubling variables and some technical analysis to prove the uniqueness result.Moreover we can prove that the L p entropy solution can be obtained as the limit of solutions of the corresponding regularized equations of nondegenerate parabolic type. 展开更多
关键词 degenerate parabolic-hyperbolic equation L p entropy solution device of doubling variables vanishing viscosity method
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THE ERGODICITY OF STOCHASTIC GENERALIZED POROUS MEDIA EQUATIONS WITH LVY JUMP 被引量:2
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作者 周国立 侯振挺 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期925-933,共9页
In this article,we first prove the existence and uniqueness of the solution to the stochastic generalized porous medium equation perturbed by Lévy process,and then show the exponential convergence of(pt)t≥0 to... In this article,we first prove the existence and uniqueness of the solution to the stochastic generalized porous medium equation perturbed by Lévy process,and then show the exponential convergence of(pt)t≥0 to equilibrium uniform on any bounded subset in H. 展开更多
关键词 stochastic porous medium equation Lévy processes ERGODICITY
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Periodic Solitary Wave Solutions of the (2 + 1)-Dimensional Variable-Coefficient Caudrey-Dodd-Gibbon-Kotera-Sawada Equation 被引量:2
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作者 Yang Zhou 《Open Journal of Applied Sciences》 2020年第3期60-68,共9页
In this paper, through symbolic computations, we obtain two exact solitary wave solitons of the (2 + l)-dimensional variable-coefficient Caudrey-Dodd- Gibbon-Kotera-Sawada equation. We study basic properties of l-peri... In this paper, through symbolic computations, we obtain two exact solitary wave solitons of the (2 + l)-dimensional variable-coefficient Caudrey-Dodd- Gibbon-Kotera-Sawada equation. We study basic properties of l-periodic solitary wave solution and interactional properties of 2-periodic solitary wave solution by using asymptotic analysis. 展开更多
关键词 (2 + l)-Dimensional vc-CDGKS equation SOLITARY WAVE SOLUTION Period-ic SOLITARY WAVE SOLUTION Asymptotic Analysis
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Third-Order Upwind Schemes for Convection Equations
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作者 丁丽娟 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期31-36,共6页
Aim To construct a third order upwind scheme for convection equation. Methods Upwind Lagrange interpolation was used. Results and Conclusion The schemes L p stability for p∈ is proved. Numerical exam... Aim To construct a third order upwind scheme for convection equation. Methods Upwind Lagrange interpolation was used. Results and Conclusion The schemes L p stability for p∈ is proved. Numerical examples show that performance of the third order upwind scheme is better than that of most second order schemes. 展开更多
关键词 upwind scheme convection equation L p stability
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Solitons and Waves in (2+l)-Dimensional Dispersive Long-Wave Equation 被引量:1
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作者 MA Zheng-Yi LIU Yu-Lu +1 位作者 LU Zhi-Ming ZHENG Chun-Long2LU Zhi-Ming,1 and ZHENG Chun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期799-803,共5页
For a higher-dimensional integrable nonlinear dynamical system, there are abundant coherent soliton excitations. With the aid of an improved projective Riccati equation approach, the paper obtains several types of exa... For a higher-dimensional integrable nonlinear dynamical system, there are abundant coherent soliton excitations. With the aid of an improved projective Riccati equation approach, the paper obtains several types of exact solutions to the (2+l)-dimenslonal dispersive long-wave equation, including multiple-soliton solutions, periodic soliton solutions, and Weierstrass function solutions. From these solutions, apart from several multisoliton excitations, we derive some novel features of wave structures by introducing some types of lower-dimensional patterns. 展开更多
关键词 (2+l)-dimensional dispersive long-wave equation projective Riccati equation approach soliton annihilation traveling wave
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STABILITY OF THE RAREFACTION WAVE FOR THE GENERALIZED KDV-BURGERS EQUATION 被引量:12
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作者 王治安 朱长江 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期319-328,共10页
This paper is concerned with the stability of the rarefaction wave for the generalized KdV-Burgers equation [GRAPHICS] Roughly speaking, under the assumption that u(-) < u(+), the solution u(x, t) to Cauchy problem... This paper is concerned with the stability of the rarefaction wave for the generalized KdV-Burgers equation [GRAPHICS] Roughly speaking, under the assumption that u(-) < u(+), the solution u(x, t) to Cauchy problem (1) satisfying (sup)(x&ISIN;R)\u(x, t) - u(R)(x/t)\ --> 0 as t --> infinity, where u(R)(x/t) is the rarefaction wave of the non-viscous Burgers equation u(t) + f(u)(x) = 0 with Riemann initial data [GRAPHICS] 展开更多
关键词 XdV-Burgers equation rarefaction wave a priori estimate L-2-energy method
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ON THE CONCENTRATION PROPERTIES FOR THE NONLINEAR SCHRDINGER EQUATION WITH A STARK POTENTIAL 被引量:1
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作者 朱世辉 张健 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1923-1938,共16页
In this paper, we study blow-up solutions of the Cauchy problem to the L2 critical nonlinear Schrdinger equation with a Stark potential. Using the variational characterization of the ground state for nonlinear Schrdin... In this paper, we study blow-up solutions of the Cauchy problem to the L2 critical nonlinear Schrdinger equation with a Stark potential. Using the variational characterization of the ground state for nonlinear Schrdinger equation without any potential, we obtain some concentration properties of blow-up solutions, including that the origin is the blow-up point of the radial blow-up solutions, the phenomenon of L2-concentration and rate of L2-concentration of blow-up solutions. 展开更多
关键词 nonlinear Schrdinger equation blow-up solution blow-up point L2-concentration concentration compact principle
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Some Numerical Extrapolation Methods for the Fractional Sub-diffusion Equation and Fractional Wave Equation Based on the L1 Formula 被引量:1
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作者 Ren-jun Qi Zhi-zhong Sun 《Communications on Applied Mathematics and Computation》 2022年第4期1313-1350,共38页
With the help of the asymptotic expansion for the classic Li formula and based on the L1-type compact difference scheme,we propose a temporal Richardson extrapolation method for the fractional sub-diffusion equation.T... With the help of the asymptotic expansion for the classic Li formula and based on the L1-type compact difference scheme,we propose a temporal Richardson extrapolation method for the fractional sub-diffusion equation.Three extrapolation formulas are presented,whose temporal convergence orders in L_(∞)-norm are proved to be 2,3-α,and 4-2α,respectively,where 0<α<1.Similarly,by the method of order reduction,an extrapola-tion method is constructed for the fractional wave equation including two extrapolation formulas,which achieve temporal 4-γ and 6-2γ order in L_(∞)-norm,respectively,where1<γ<2.Combining the derived extrapolation methods with the fast algorithm for Caputo fractional derivative based on the sum-of-exponential approximation,the fast extrapolation methods are obtained which reduce the computational complexity significantly while keep-ing the accuracy.Several numerical experiments confirm the theoretical results. 展开更多
关键词 L1 formula Asymptotic expansion Fractional sub-diffusion equation Fractional wave equation Richardson extrapolation Fast algorithm
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NONLINEAR STABILITY OF PLANAR SHOCK PROFILES FOR THE GENERALIZED KdV-BURGERS EQUATION IN SEVERAL DIMENSIONS 被引量:1
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作者 陈正争 肖清华 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1531-1550,共20页
This paper is concerned with the nonlinear stability of planar shock profiles to the Cauchy problem of the generalized KdV-Burgers equation in two dimensions. Our analysis is based on the energy method developed by Go... This paper is concerned with the nonlinear stability of planar shock profiles to the Cauchy problem of the generalized KdV-Burgers equation in two dimensions. Our analysis is based on the energy method developed by Goodman [5] for the nonlinear stability of scalar viscous shock profiles to scalar viscous conservation laws and some new decay estimates on the planar shock profiles of the generalized KdV-Burgers equation. 展开更多
关键词 generalized KdV-Burgers equation shock profiles nonlinear stability L^2 energy estimate
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Dynamics of solitons of the generalized(3+1)-dimensional nonlinear Schr(o|¨)dinger equation with distributed coefficients
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作者 刘晓蓓 李彪 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期339-345,共7页
We present three families of soliton solutions to the generalized (3+l)-dimensional nonlinear Schrodinger equation with distributed coefficients. We investigate the dynamics of these solitons in nonlinear optics wi... We present three families of soliton solutions to the generalized (3+l)-dimensional nonlinear Schrodinger equation with distributed coefficients. We investigate the dynamics of these solitons in nonlinear optics with some selected parameters. Different shapes of bright solitons, a train of bright solitons and dark solitons are observed. The obtained results may raise the possibilities of relevant experiments and potential applications. 展开更多
关键词 (3+l)-dimensional nonlinear Schodinger equation optical soliton soliton propagation
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