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Segmentation and classification of high spatial resolution images based on Hölder exponents and variance
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作者 Debasish Chakraborty Sourabh Singh Dibyendu Dutta 《Geo-Spatial Information Science》 SCIE EI CSCD 2017年第1期39-45,共7页
Pixel-based or texture-based classification technique individually does not yield an appropriate result in classifying the high spatial resolution remote sensing imagery since it comprises textured and non-textured re... Pixel-based or texture-based classification technique individually does not yield an appropriate result in classifying the high spatial resolution remote sensing imagery since it comprises textured and non-textured regions.In this study,Hölder exponents(HE)and variance(VAR)are used together to transform the image for measuring texture.A threshold is derived to segment the transformed image into textured and non-textured regions.Subsequently,the original image is extracted into textured and non-textured regions using this segmented image mask.Afterward,extracted textured region is classified using ISODATA classification algorithm considering HE,VAR,and intensity values of individual pixel of textured region.And extracted non-textured region of the image is classified using ISODATA classification algorithm.In case of non-textured region,HE and VAR value of individual pixel is not considered for classification for significant textural variation is not found among different classes.Consequently,the classified outputs of non-textured and textured regions that are generated independently are merged together to get the final classified image.IKONOS 1 m PAN images are classified using the proposed algorithm,and the classification accuracy is more than 88%. 展开更多
关键词 high-resolution image texture SEGMENTATION hölder exponents variance CONTRAST classification ISODATA
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Strong Feller Property for SDEs with Super-linear Drift and Hölder Diffusion Coefficients
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作者 WANG Yanmin SHA Xiang GUO Zhongkai 《应用数学》 北大核心 2024年第4期1066-1073,共8页
In this paper,we investigate the strong Feller property of stochastic differential equations(SDEs)with super-linear drift and Hölder diffusion coefficients.By utilizing the Girsanov theorem,coupling method,trunca... In this paper,we investigate the strong Feller property of stochastic differential equations(SDEs)with super-linear drift and Hölder diffusion coefficients.By utilizing the Girsanov theorem,coupling method,truncation method and the Yamada-Watanabe approximation technique,we derived the strong Feller property of the solution. 展开更多
关键词 Super-linear drift hölder continuous diffusion SDEs Strong Feller
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Existence of a Hölder Continuous Extension on Embedded Balls of the 3-Torus for the Periodic Navier Stokes Equations
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作者 Terry E. Moschandreou 《Advances in Pure Mathematics》 2024年第2期118-138,共21页
This article gives a general model using specific periodic special functions, which is degenerate elliptic Weierstrass P functions whose presence in the governing equations through the forcing terms simplify the perio... This article gives a general model using specific periodic special functions, which is degenerate elliptic Weierstrass P functions whose presence in the governing equations through the forcing terms simplify the periodic Navier Stokes equations (PNS) at the centers of cells of the 3-Torus. Satisfying a divergence-free vector field and periodic boundary conditions respectively with a general spatio-temporal forcing term which is smooth and spatially periodic, the existence of solutions which have finite time singularities can occur starting with the first derivative and higher with respect to time. The existence of a subspace of the solution space where v<sub>3</sub> is continuous and {C, y<sub>1</sub>, y<sub>1</sub><sup>2</sup>}, is linearly independent in the additive argument of the solution in terms of the Lambert W function, (y<sub>1</sub><sup>2</sup>=y<sub>2</sub>, C∈R) together with the condition v<sub>2</sub>=-2y<sub>1</sub>v<sub>1</sub>. On this subspace, the Biot Savart Law holds exactly [see Section 2 (Equation (13))]. Also on this subspace, an expression X (part of PNS equations) vanishes which contains all the expressions in derivatives of v<sub>1</sub> and v<sub>2</sub> and the forcing terms in the plane which are related as with the cancellation of all such terms in governing PDE. The y<sub>3</sub> component forcing term is arbitrarily small in ε ball where Weierstrass P functions touch the center of the ball both for inviscid and viscous cases. As a result, a significant simplification occurs with a v<sub>3 </sub>only governing PDE resulting. With viscosity present as v changes from zero to the fully viscous case at v =1 the solution for v<sub>3</sub> reaches a peak in the third component y<sub>3</sub>. Consequently, there exists a dipole which is not centered at the center of the cell of the Lattice. Hence since the dipole by definition has an equal in magnitude positive and negative peak in y<sub>3</sub>, then the dipole Riemann cut-off surface is covered by a closed surface which is the sphere and where a given cell of dimensions [-1, 1]<sup>3</sup> is circumscribed on a sphere of radius 1. For such a closed surface containing a dipole it necessarily follows that the flux at the surface of the sphere of v<sub>3</sub> wrt to surface normal n is zero including at the points where the surface of sphere touches the cube walls. At the finite time singularity on the sphere a rotation boundary condition is deduced. It is shown that v<sub>3</sub> is spatially finite on the Riemann Sphere and the forcing is oscillatory in y<sub>3</sub> component if the velocity v3</sub> is. It is true that . A boundary condition on the sphere shows the rotation of a sphere of viscous fluid. Finally on the sphere a solution for v3</sub> is obtained which is proven to be Hölder continuous and it is shown that it is possible to extend Hölder continuity on the sphere uniquely to all of the interior of the ball. 展开更多
关键词 Navier-Stokes PNS 3-Torus PERIODIC Ball Sphere hölder CONTINUOUS Riemann-Surface Uniqueness
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From Hölder Continuous Solutions of 3D Incompressible Navier-Stokes Equations to No-Finite Time Blowup on [ 0,∞ ]
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作者 Terry E. Moschandreou 《Advances in Pure Mathematics》 2024年第9期695-743,共49页
This article gives a general model using specific periodic special functions, that is, degenerate elliptic Weierstrass P functions composed with the LambertW function, whose presence in the governing equations through... This article gives a general model using specific periodic special functions, that is, degenerate elliptic Weierstrass P functions composed with the LambertW function, whose presence in the governing equations through the forcing terms simplify the periodic Navier Stokes equations (PNS) at the centers of arbitrary r balls of the 3-Torus. The continuity equation is satisfied together with spatially periodic boundary conditions. The yicomponent forcing terms consist of a function F as part of its expression that is arbitrarily small in an r ball where it is associated with a singular forcing expression both for inviscid and viscous cases. As a result, a significant simplification occurs with a v3(vifor all velocity components) only governing PDE resulting. The extension of three restricted subspaces in each of the principal directions in the Cartesian plane is shown as the Cartesian product ℋ=Jx,t×Jy,t×Jz,t. On each of these subspaces vi,i=1,2,3is continuous and there exists a linear independent subspace associated with the argument of the W function. Here the 3-Torus is built up from each compact segment of length 2R on each of the axes on the 3 principal directions x, y, and z. The form of the scaled velocities for non zero scaled δis related to the definition of the W function such that e−W(ξ)=W(ξ)ξwhere ξdepends on t and proportional to δ→0for infinite time t. The ratio Wξis equal to 1, making the limit δ→0finite and well defined. Considering r balls where the function F=(x−ai)2+(y−bi)2+(z−ci)2−ηset equal to −1e+rwhere r>0. is such that the forcing is singular at every distance r of centres of cubes each containing an r-ball. At the centre of the balls, the forcing is infinite. The main idea is that a system of singular initial value problems with infinite forcing is to be solved for where the velocities are shown to be locally Hölder continuous. It is proven that the limit of these singular problems shifts the finite time blowup time ti∗for first and higher derivatives to t=∞thereby indicating that there is no finite time blowup. Results in the literature can provide a systematic approach to study both large space and time behaviour for singular solutions to the Navier Stokes equations. Among the references, it has been shown that mathematical tools can be applied to study the asymptotic properties of solutions. 展开更多
关键词 Navier-Stokes Periodic Navier-Stokes Equations 3-Torus PERIODIC Ball Sphere hölder Continuous Functions Uniqueness Angular Velocity Velocity in Terms of Vorticity
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Hölder不等式的两种新证法及Cauchy-Schwarz不等式的加细
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作者 施俊 刘建忠 彭庆英 《江苏理工学院学报》 2024年第2期1-4,共4页
Hölder不等式是一类重要的不等式。本文分别利用Cauchy-Schwarz不等式及关于凸函数的Jensen不等式,给出了积分型Hölder不等式的两种新的证明方法。据此,结合受控理论给出Cauchy-Schwarz不等式的一种加细及一个新的反向Hö... Hölder不等式是一类重要的不等式。本文分别利用Cauchy-Schwarz不等式及关于凸函数的Jensen不等式,给出了积分型Hölder不等式的两种新的证明方法。据此,结合受控理论给出Cauchy-Schwarz不等式的一种加细及一个新的反向Hölder不等式。 展开更多
关键词 CAUChY-SChWARZ不等式 hölder不等式 JENSEN不等式 凸函数 Schur凸函数
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Hölder不等式的一种新证法及推广
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作者 施俊 刘建忠 彭庆英 《数学教学》 2024年第3期13-16,共4页
1引言Hölder不等式是非常重要的不等式,本文首先给出Hölder不等式的一个等价形式,然后利用函数的凸性给出了Hölder不等式的一种新的证明方法,并据此结合受控理论(theory of majorization)给出Cauchy-Schwarz不等式的一... 1引言Hölder不等式是非常重要的不等式,本文首先给出Hölder不等式的一个等价形式,然后利用函数的凸性给出了Hölder不等式的一种新的证明方法,并据此结合受控理论(theory of majorization)给出Cauchy-Schwarz不等式的一种加细及一个新的反向Hölder不等式.我们需要一些简单的符号和高等数学知识. 展开更多
关键词 等价形式 函数的凸性 加细 新证法 hölder不等式 高等数学知识 CAUChY-SChWARZ不等式
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Robust H∞ Control with Exponent Stability for Time-Delay Uncertain Systems 被引量:1
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作者 Luo Xiaoyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第1期27-33,共7页
This paper is concerned with the robust H ∞ control with exponent stability for a class of time delay uncertain systems. Attention is focused on the design of controllers such that the resulting closed loop system... This paper is concerned with the robust H ∞ control with exponent stability for a class of time delay uncertain systems. Attention is focused on the design of controllers such that the resulting closed loop system not only is exponentially stable but also satisfies, H ∞ disturbance attenuance via memoryless state feedback control. Sufficient conditions for feasibility are obtained in terms of LMIs. Moreover, optimization of LMI is considered such that the controller with low gain parameters is formulated. 展开更多
关键词 Uncertain system Time delay Robust h control exponent attenuance LMI.
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Hölder Derivative of the Koch Curve
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作者 Guangjun Yang Xiaoling Yang Ping Wang 《Journal of Applied Mathematics and Physics》 2023年第1期101-114,共14页
In this paper, we introduce a K H&#246;lder p-adic derivative that can be applied to fractal curves with different H&#246;lder exponent K. We will show that the Koch curve satisfies the H&#246;lder conditi... In this paper, we introduce a K H&#246;lder p-adic derivative that can be applied to fractal curves with different H&#246;lder exponent K. We will show that the Koch curve satisfies the H&#246;lder condition with exponent and has a 4-adic arithmetic-analytic representation. We will prove that the Koch curve has exact -H&#246;lder 4-adic derivative. 展开更多
关键词 FRACTAL Koch Curve hölder Inequality hölder Derivative
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可积函数HÖlder不等式的等价不等式
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作者 沈诗雨 张盛婕 张文彬 《应用数学进展》 2023年第3期1068-1076,共9页
HÖlder不等式在分析学和初等不等式理论中扮演着极其重要的角色。作为相关研究的一个重要方面, 它与其它不等式之间的等价关系的研究也越来越受到重视。本文证明了测度空间上积分形式的H¨older不等式与算术平均-几何平均不等... HÖlder不等式在分析学和初等不等式理论中扮演着极其重要的角色。作为相关研究的一个重要方面, 它与其它不等式之间的等价关系的研究也越来越受到重视。本文证明了测度空间上积分形式的H¨older不等式与算术平均-几何平均不等式,以及它与喜平均不等式之间的等价关系。这些结果极大地推广了李勇涛等最近建立的离散不等式等价关系。 展开更多
关键词 hölder不等式 算术平均-几何平均不等式 喜平均不等式 等价性
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THE WEIGHTED KATO SQUARE ROOT PROBLEMOF ELLIPTIC OPERATORS HAVING A BMOANTI-SYMMETRICPART
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作者 马文贤 杨四辈 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期532-550,共19页
Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted... Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted Kato square root problem for L.More precisely,we prove that the square root L^(1/2)satisfies the weighted L^(p)estimates||L^(1/2)(f)||L_(ω)^p(R^(n))≤C||■f||L_(ω)^p(R^(n);R^(n))for any p∈(1,∞)andω∈Ap(ℝ^(n))(the class of Muckenhoupt weights),and that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,2+ε)andω∈Ap(ℝ^(n))∩RH_(2+ε/p),(R^(n))(the class of reverse Hölder weights),whereε∈(0,∞)is a constant depending only on n and the operator L,and where(2+ε/p)'denotes the Hölder conjugate exponent of 2+ε/p.Moreover,for any given q∈(2,∞),we give a sufficient condition to obtain that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,q)andω∈A_(p)(R^(n))∩pRH_(q/p),(R^(n)).As an application,we prove that when the coefficient matrix A that appears in L satisfies the small BMO condition,the Riesz transform∇L^(−1/2)is bounded on L_(ω)^(p)(ℝ^(n))for any given p∈(1,∞)andω∈Ap(ℝ^(n)).Furthermore,applications to the weighted L^(2)-regularity problem with the Dirichlet or the Neumann boundary condition are also given. 展开更多
关键词 elliptic operator Kato square root problem Muckenhoupt weight Riesz transform reverse hölder inequality
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一类Hlder连续的混沌系统分析和控制 被引量:2
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作者 张建雄 唐万生 《系统工程学报》 CSCD 北大核心 2010年第6期829-834,共6页
构造了新的三维连续时间混沌系统.该系统含有两个参数和一个非线性项,其中的非线性项满足1/2阶Hlder连续但不满足Lipschitz连续性条件.通过理论分析和数值仿真研究了系统的动力学特性.此外,利用线性状态反馈对此混沌系统进行了控制,... 构造了新的三维连续时间混沌系统.该系统含有两个参数和一个非线性项,其中的非线性项满足1/2阶Hlder连续但不满足Lipschitz连续性条件.通过理论分析和数值仿真研究了系统的动力学特性.此外,利用线性状态反馈对此混沌系统进行了控制,实现了系统的全局镇定.通过分段线性状态反馈方法对新混沌系统的同步进行了研究,实现了系统的全局同步. 展开更多
关键词 混沌系统 hlder连续 线性反馈 同步
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度量空间中某类泛函极小的Hlder连续性 被引量:2
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作者 陈平 刘海蓉 《安徽师范大学学报(自然科学版)》 CAS 北大核心 2012年第2期103-106,共4页
主要研究了牛顿空间中泛函F(u,gu)=∫f(u,gu)dμ的极小问题,其中对某常数c>0,泛函满足gup-c|u|p≤f(u,gu)≤gpu+c|u|p.牛顿空间是Sobolev空间在度是空间中的推广,具有更一般的性质.在该空间中研究偏微分方程,对建立更一般的偏微分方... 主要研究了牛顿空间中泛函F(u,gu)=∫f(u,gu)dμ的极小问题,其中对某常数c>0,泛函满足gup-c|u|p≤f(u,gu)≤gpu+c|u|p.牛顿空间是Sobolev空间在度是空间中的推广,具有更一般的性质.在该空间中研究偏微分方程,对建立更一般的偏微分方程理论具有指导和开拓意义.本文利用De Giorgi迭代的方法研究了该泛函极小的正则性,证明了该泛函极小的Hlder连续性.这使得我们在不求精确解的情况下,利用方程本身的条件可以对方程解进行数值估计. 展开更多
关键词 Newton空间 hlder连续性 DE Giorgi迭代
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从贝努利不等式到Hlder不等式的演变过程及应用 被引量:1
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作者 邢家省 王洪志 《吉首大学学报(自然科学版)》 CAS 2010年第2期10-14,共5页
首先利用贝努利不等式给出几何平均算术平均不等式的证明,然后给出Young不等式和Young逆不等式的初等证明方法,进而给出Hlder不等式的初等证明,并将这些结果应用到一些重要不等式的证明.
关键词 贝努利不等式 几何平均算术平均不等式 YOUNG不等式 hlder不等式 MINKOWSKI不等式
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A-调和方程弱解的逆Hlder不等式及其应用 被引量:2
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作者 高红亚 陈银珠 《应用数学》 CSCD 北大核心 2002年第4期102-104,共3页
本文给出A 调和方程弱解的逆H lder不等式及其若干应用 .
关键词 弱解 A-调和方程 holder不等式 拟正则映射
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一个抛物型方程侧边值问题的具有Hlder连续性的Fourier正则化方法(英文) 被引量:1
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作者 傅初黎 熊向团 李洪芳 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第2期5-7,共3页
逆热传导问题是具有重要应用背景的严重不适定问题,但目前已有结果大都仅局限于标准的热传导方程侧边值问题的讨论.本文对一个抛物型方程侧边值问题给出了一种新的具有Hlder连续性的Fourier正则化方法。
关键词 抛物方程侧边值问题 不适定问题 正则化 hoelder稳定性
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具有单调、Hlder连续及可积参数的一维倒向随机微分方程(英文) 被引量:1
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作者 肖立顺 李慧颖 范胜君 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第1期130-137,共8页
建立了具有可积参数的一维倒向随机微分方程(BSDE)解的一个存在唯一性结果,其中生成元g关于y单调且关于z是α-Hlder(0<α<1)连续的.利用Tanaka公式及Girsanov变换建立BSDE的L^1解的一个比较定理,从而得到解的唯一性.使用卷积技... 建立了具有可积参数的一维倒向随机微分方程(BSDE)解的一个存在唯一性结果,其中生成元g关于y单调且关于z是α-Hlder(0<α<1)连续的.利用Tanaka公式及Girsanov变换建立BSDE的L^1解的一个比较定理,从而得到解的唯一性.使用卷积技术给出生成元g的一个一致逼近序列并借助于它构造出BSDE的L^1解的一个序列,然后证明其极限即为所需的解,从而证明解的存在性. 展开更多
关键词 倒向随机微分方程 可积参数 单调生成元 hlder连续 存在唯一性
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Hlder不等式的初等证明及其应用 被引量:5
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作者 邢家省 郭秀兰 朱建设 《河南科学》 2009年第12期1484-1488,共5页
首先利用贝努利不等式给出了几何平均算术平均不等式的证明,其次给出了Young不等式和Young逆不等式的初等证明方法,进而给出了Hlder不等式的初等证明,沟通了这些重要的不等式之间在初等数学阶段的联系.
关键词 贝努利不等式 几何平均算术平均不等式 YOUNG不等式 hlder不等式 MINKOWSKI不等式
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Clifford分析中拟Cauchy型积分的Hlder连续性 被引量:1
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作者 乔海英 王丽萍 乔玉英 《高校应用数学学报(A辑)》 CSCD 北大核心 2010年第3期333-342,共10页
以拟Cauchy型积分公式及超正则函数的Plemelj公式为基础,进一步研究了拟Cauchy型积分的H(o|¨)lder连续性:即对两点都在边界上;一点在边界上,另一点在区域内(区域外);两点都在区域内(两点都在区域外)这三种情形分别进行了研究.
关键词 CLIFFORD分析 超正则函数 拟Cauchy型积分 h(o|¨)lder连续性
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一类三角插值多项式在Hlder度量下的逼近 被引量:5
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作者 侯象乾 《宁夏大学学报(自然科学版)》 CAS 2001年第3期282-283,共2页
研究在H lder度量下 ,双周期 (0 ,m)三角插值多项式 (m为偶数 )的逼近与饱和 。
关键词 hOElder度量 饱和 三角插值多项式 逼近
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一个障碍问题解梯度的 Hlder 连续性 被引量:4
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作者 梁(派金)廷 于鸣岐 《数学杂志》 CSCD 北大核心 1993年第3期298-306,共9页
证明一个变分不等式单侧障碍问题解梯度的 H(o|¨)lder 连续性,证实了 Lindqvist的一个猜想.
关键词 障碍问题 梯度 h连续性
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