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Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem 被引量:5
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作者 SUN Yong-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期413-419,共7页
The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied.... The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″(t) + q(t)f(t,u(t),u′(t)) = 0, 0 〈 t 〈 1, u(0) = u″(0) = u′(1) = 0 is studied. The iterative schemes for approximating the solutions are obtained by applying a monotone iterative method. 展开更多
关键词 third-order two-point boundary value problem monotone iterative method positive solution existence iterative scheme
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A Pseudo-Spectral Scheme for Systems of Two-Point Boundary Value Problems with Left and Right Sided Fractional Derivatives and Related Integral Equations
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作者 I.G.Ameen N.A.Elkot +2 位作者 M.A.Zaky A.S.Hendy E.H.Doha 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第7期21-41,共21页
We target here to solve numerically a class of nonlinear fractional two-point boundary value problems involving left-and right-sided fractional derivatives.The main ingredient of the proposed method is to recast the p... We target here to solve numerically a class of nonlinear fractional two-point boundary value problems involving left-and right-sided fractional derivatives.The main ingredient of the proposed method is to recast the problem into an equivalent system of weakly singular integral equations.Then,a Legendre-based spectral collocation method is developed for solving the transformed system.Therefore,we can make good use of the advantages of the Gauss quadrature rule.We present the construction and analysis of the collocation method.These results can be indirectly applied to solve fractional optimal control problems by considering the corresponding Euler–Lagrange equations.Two numerical examples are given to confirm the convergence analysis and robustness of the scheme. 展开更多
关键词 Spectral collocation method weakly singular integral equations two-point boundary value problems convergence analysis
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Existence of Solutions of Two-Point Boundary Value Problems for 4n th-Order Nonlinear Differential Equation
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作者 高永馨 石新华 《Transactions of Tianjin University》 EI CAS 2004年第2期158-161,共4页
By using the method of upper and lower solution, some conditions of the existence of solutions of nonlinear two-point boundary value problems for 4nth-order nonlinear differential equation are studied.
关键词 nth-order nonlinear differential equation nonlinear two-point boundary value problem existence of solutions
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Existence of solutions of nonlinear two-point boundary value problems for 4nth-order nonlinear differential equation 被引量:3
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作者 GAO Yong-xin(高永馨) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第4期424-428,共5页
Studies the existence of solutions of nonlinear two point boundary value problems for nonlinear 4n-th-order differential equationy (4n)=f(t,y,y′,y″,...,y (4n-1))(a)with the boundary conditions g 2i(y (2i)(a),y (2i+1... Studies the existence of solutions of nonlinear two point boundary value problems for nonlinear 4n-th-order differential equationy (4n)=f(t,y,y′,y″,...,y (4n-1))(a)with the boundary conditions g 2i(y (2i)(a),y (2i+1)(a))=0,h 2i(y (2i)(c),y (2i+1)(c))=0,(i=0,1,...,2n-1)(b) where the functions f, g i and h i are continuous with certain monotone properties. For the boundary value problems of nonlinear nth order differential equationy (n)=f(t,y,y′,y″,...,y (n-1))many results have been given at the present time. But the existence of solutions of boundary value problem (a),(b) studied in this paper has not been covered by the above researches. Moreover, the corollary of the important theorem in this paper, i.e. existence of solutions of the boundary value problem.y (4n)=f(t,y,y′,y″,...,y (4n-1)) a 2iy (2i)(a)+a 2i+1y (2i+1)(a)=b 2i,c 2iy (2i)(c)+c 2i+1y (2i+1)(c)=d 2i,(i=0,1,...2n-1)has not been dealt with in previous works. 展开更多
关键词 NONLINEAR 4n-th order DIFFERENTIAL EQUATION NONLINEAR two point boundary VALUE problems EXISTENCE of solutions
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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
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Existence of Multiple Positive Solutions for Fourth Order Two-point Boundary Value Problems 被引量:1
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作者 戚仕硕 《Northeastern Mathematical Journal》 CSCD 2002年第1期63-72,共10页
The present paper tackles two-point boundary value problems for fourth-order differential equations as follows:Several existence theorems on multiple positive solutions to the problems are obtained, and some examples ... The present paper tackles two-point boundary value problems for fourth-order differential equations as follows:Several existence theorems on multiple positive solutions to the problems are obtained, and some examples are given to show the validity of these results. 展开更多
关键词 existence theorem multiple positive solution fourth-order boundary value problem
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ASYMPTOTIC ERROR EXPANSIONS OF QUADRATIC SPLINE COLLOCATION SOLUTIONS FOR TWO-POINT BOUNDARY VALUE PROBLEMS
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作者 韩国强 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1994年第2期120-125,共6页
In this paper, we consider the following problem:The quadratic spline collocation, with uniform mesh and the mid-knot points are taken as the collocation points for this problem is considered. With some assumptions, w... In this paper, we consider the following problem:The quadratic spline collocation, with uniform mesh and the mid-knot points are taken as the collocation points for this problem is considered. With some assumptions, we have proved that the solution of the quadratic spline collocation for the nonlinear problem can be written as a series expansions in integer powers of the mesh-size parameter. This gives us a construction method for using Richardson’s extrapolation. When we have a set of approximate solution with different mesh-size parameter a solution with high accuracy can he obtained by Richardson’s extrapolation. 展开更多
关键词 ASYMPTOTIC error expansion QUADRATIC SPLINE COLLOCATION method two-point boundary value problem Richardson’s extrapolation.
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An Existence Theorem of Solution for a Singular Third-order Two-point Boundary Value Problem 被引量:1
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作者 姚庆六 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期61-66,共6页
By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′... By constructing suitable Banach space, an existence theorem is established under a condition of linear growth for the third-order boundary value problem u″′(t)+f(t,u(t),u′(t))=0,0〈t〈1,u(0)=u′(0)=u′(1)=0, where the nonlinear term contains first and second derivatives of unknown function. In this theorem the nonlinear term f(t, u, v, w) may be singular at t = 0 and t = 1. The main ingredient is Leray-Schauder nonlinear alternative. 展开更多
关键词 singular ordinary differential equation boundary value problem existence theorem nonlinear alternative
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A Special Case of Variational Formulation for Two-Point Boundary Value Problem in L2(Ω)
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作者 Pedro Pablo Cárdenas Alzate 《Applied Mathematics》 2015年第4期700-706,共7页
We consider the nonlinear boundary value problems for elliptic partial differential equations and using a maximum principle for this problem we show uniqueness and continuous dependence on data. We use the strong vers... We consider the nonlinear boundary value problems for elliptic partial differential equations and using a maximum principle for this problem we show uniqueness and continuous dependence on data. We use the strong version of the maximum principle to prove that all solutions of two-point BVP are positives and we also show a numerical example by applying finite difference method for a two-point BVP in one dimension based on discrete version of the maximum principle. 展开更多
关键词 two-point boundary VARIATIONAL Problem Stability RESTRICTION
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Numerical Solution of Singularly Perturbed Two-Point Boundary Value Problem via Liouville-Green Transform
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作者 Hradyesh Kumar Mishra Sonali Saini 《American Journal of Computational Mathematics》 2013年第1期1-5,共5页
In this paper, authors describe a Liouville-Green transform to solve a singularly perturbed two-point boundary value problem with right end boundary layer in the interval [0, 1]. They reply Liouville-Green transform i... In this paper, authors describe a Liouville-Green transform to solve a singularly perturbed two-point boundary value problem with right end boundary layer in the interval [0, 1]. They reply Liouville-Green transform into original given problem and finds the numerical solution. Then they implemented this method on two linear examples with right end boundary layer which nicely approximate the exact solution. 展开更多
关键词 Singular Perturbation Ordinary Differential Equation boundary Layer two-point boundary Value Problem Liouville-Green TRANSFORM
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A Class of a Second-Order Two-Point Boundary Value Problem on a Measure Chain
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作者 杜增吉 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期104-107,共4页
A class of second-order two-point boundary value problem on a measure chain was considered. Under some suitable conditions, by using the Leggett-Williams fixed point theorem in an appropriate cone, the existence of at... A class of second-order two-point boundary value problem on a measure chain was considered. Under some suitable conditions, by using the Leggett-Williams fixed point theorem in an appropriate cone, the existence of at least three positive solutions to this nonlinear problem was obtained. 展开更多
关键词 boundary value problem measure chains fixed point theorem
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A Two-Point Boundary Value Problem by Using a Mixed Finite Element Method
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作者 Pedro Pablo Cárdenas Alzate José Rodrigo González Granada 《Applied Mathematics》 2015年第12期1996-2003,共8页
This paper describes a numerical solution for a two-point boundary value problem. It includes an algorithm for discretization by mixed finite element method. The discrete scheme allows the utilization a finite element... This paper describes a numerical solution for a two-point boundary value problem. It includes an algorithm for discretization by mixed finite element method. The discrete scheme allows the utilization a finite element method based on piecewise linear approximating functions and we also use the barycentric quadrature rule to compute the stiffness matrix and the L2-norm. 展开更多
关键词 two-point BVP Galerkin’s METHOD Non-Symmetric PROBLEM
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Existence of Multiple Positive Solutions for <i>n</i><sup>th</sup>Order Two-Point Boundary Value Problems on Time Scales
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作者 Kapula Rajendra Prasad Penugurthi Murali Nadakuduti V. V. S. Suryanarayana 《Advances in Pure Mathematics》 2013年第1期70-77,共8页
We consider the nth order nonlinear differential equation on time scales subject to the right focal type two-point boundary conditions We establish a criterion for the existence of at least one positive solution by ut... We consider the nth order nonlinear differential equation on time scales subject to the right focal type two-point boundary conditions We establish a criterion for the existence of at least one positive solution by utilizing Krasnosel’skii fixed point theorem. And then, we establish the existence of at least three positive solutions by utilizing Leggett-Williams fixed point theorem. 展开更多
关键词 Time Scale Dynamical Equation Positive Solution CONE boundary Value Problem
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ON THE EXISTENCE OF SOLUTION OF A NONLINEAR TWO-POINT BOUNDARY VALUE PROBLEM ARISING FROM A LIQUID METAL FLOW
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作者 程晓良 应玮婷 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第4期351-356,共6页
In this paper, we discuss the existence of solution of a nonlinear two-point boundary value problem with a positive parameter Q arising in the study of surfacetension-induced flows of a liquid metal or semiconductor. ... In this paper, we discuss the existence of solution of a nonlinear two-point boundary value problem with a positive parameter Q arising in the study of surfacetension-induced flows of a liquid metal or semiconductor. By applying the Schauder's fixed-point theorem, we prove that the problem admits a solution for 0 ≤ Q ≤ 14.306.It improves the result of 0 ≤ Q < 1 in [2] and 0 ≤ Q ≤ 13.213 in [3]. 展开更多
关键词 边值问题 Schauder固定点 估计解 存在性
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Formation and solute segregation for an asymmetric tilt boundary on{1012}twin boundaries 被引量:1
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作者 Qiang Yang Shuhui Lv +3 位作者 Peng Chen Zefeng Xie Shuo Zhou Xin Qiu 《Journal of Magnesium and Alloys》 2025年第2期583-591,共9页
Asymmetric tilt boundaries on conventional twin boundaries(TBs)are significant for understanding the role of twins on coordinating plastic deformation in many metallic alloys.However,the formation modes of many asymme... Asymmetric tilt boundaries on conventional twin boundaries(TBs)are significant for understanding the role of twins on coordinating plastic deformation in many metallic alloys.However,the formation modes of many asymmetric tilt boundaries are hard to be accounted for based on traditional theoretical models,and the corresponding solute segregation is complex.Herein,atomic structures of a specific asymmetric boundary on{1012}TBs were reveled using aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),molecular dynamics(MD)and density functional theory(DFT)simulations.Reaction between<a60>M dislocations and the{1012}TB can generate a~61°/25°asymmetric tilt boundary.The segregation of Gd and Zn atoms is closely related to the aggregateddislocations and the interfacial interstices of the asymmetric tilt boundary,which is energetically favorable in reducing the total system energy. 展开更多
关键词 Magnesium alloy Transmission electron microscopy Twin boundary DISLOCATION SEGREGATION
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MODELING OF A MICROPOLAR THIN FILM FLOW WITH RAPIDLY VARYING THICKNESS AND NON-STANDARD BOUNDARY CONDITIONS
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作者 María ANGUIANO Francisco Javier SUÁREZ-GRAU 《Acta Mathematica Scientia》 2026年第1期209-242,共34页
In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary c... In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary conditions on the flat bottom.Assuming“Reynolds roughness regime”,in which the thickness of the domain is very small compared to the wavelength of the roughness(i.e.a very slight roughness),we rigorously derive a generalized Reynolds equation for pressure,clearly showing the roughness-induced effects.Moreover,we give expressions for the average velocity and microrotation. 展开更多
关键词 micropolar fluid thin-film flow rapidly oscillating boundary nonzero boundary conditions HOMOGENIZATION
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Tracing equatorward and poleward boundaries of the magnetospheric cusp from a simulated X-ray image
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作者 Xue Wang TianRan Sun +4 位作者 C.Philippe Escoubet Andy Read YiHong Guo Steve Sembay Chi Wang 《Earth and Planetary Physics》 2026年第1期144-155,共12页
A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-d... A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image. 展开更多
关键词 SMILE mission X-ray image cusp boundary
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Mechanisms of Pore-Grain Boundary Interactions Influencing Nanoindentation Behavior in Pure Nickel: A Molecular Dynamics Study
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作者 Chen-Xi Hu Wu-Gui Jiang +1 位作者 Jin Wang Tian-Yu He 《Computers, Materials & Continua》 2026年第1期368-388,共21页
THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between c... THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between crystallographic orientation,grain boundary(GB)proximity,and pore characteristics(size/location).This study compares single-crystal nickel models along[100],[110],and[111]orientations with equiaxed polycrystalline models containing 0,1,and 2.5 nm pores in surface and subsurface configurations.Our results reveal that crystallographic anisotropy manifests as a 24.4%higher elastic modulus and 22.2%greater hardness in[111]-oriented single crystals compared to[100].Pore-GB synergistic effects are found to dominate the deformation behavior:2.5 nm subsurface pores reduce hardness by 25.2%through stress concentration and dislocation annihilation at GBs,whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse.Additionally,size-dependent deformation regimes were identified,with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement,in contrast with persistent softening in 2.5 nm pores.These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components,demonstrating how crystallographic orientation,pore configuration,and GB interactions collectively govern nanoindentation behavior. 展开更多
关键词 Pure nickel NANOINDENTATION molecular dynamics PORE grain boundary
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Existence,Uniqueness and Stability of Bounded Solutions for Minkowski-Curvature Problems with Asymptotic Boundary Conditions
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作者 Tianlan CHEN Xuying TANG 《Journal of Mathematical Research with Applications》 2026年第1期57-70,共14页
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→... In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions. 展开更多
关键词 mean curvature operator UNIQUENESS asymptotic boundary conditions bounded solution
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NONLINEAR RIEMANN AND HILBERT BOUNDARY VALUE PROBLEMS WITH SQUARE ROOTS IN VARIABLE EXPONENT SPACES
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作者 Yajun Hu Fuli He 《Acta Mathematica Scientia》 2026年第1期1-18,共18页
In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zer... In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zero-points distribution of the solutions and separate the single valued analytic branch of the solutions with square roots,then convert the problem to a Riemann boundary value problem in variable exponent Lebesgue spaces and discuss the singularity of solutions at individual zeros belonging to curve.We consider two types of cases those where the coefficient is Hölder and those where it is piecewise Hölder.Then we solve the Hilbert boundary value problem with square roots in variable exponent Lebesgue spaces.By discussing the distribution of the odd-order zero-points for solutions and the method of symmetric extension,we convert the Hilbert problem to a Riemann boundary value problem.The equivalence of the transformation is discussed.Finally,we get the solvable conditions and the direct expressions of the solutions in variable exponent Lebesgue spaces. 展开更多
关键词 boundary value problem Cauchy-type integral variable exponent spaces non-linearity piecewise Lyapunov curve
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