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The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem
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作者 Bijay Kumar Sharma 《International Journal of Astronomy and Astrophysics》 2024年第1期1-19,共19页
Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubatio... Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius a<sub>H</sub> and planet mean radius R<sub>P </sub>and the ratio R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub>. Under very low R<sub>1 </sub>(less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub> =0.01 and 5.9862 × 10<sup>-3</sup> respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study. 展开更多
关键词 Hill’s Radius Two-Body problem Fixed-Point solution Lagrange Points Earth-Moon-Test Particle CRTBP
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S-T-S混合式循环互助教学模式用于少学时“化工原理”课程
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作者 吕玲 《教育教学论坛》 2024年第31期157-160,共4页
“化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题... “化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题,学生帮助教师反馈真实学习情况,学生帮助学生组团互助学习。问卷调查和评教结果显示,在一定程度上解决了“三多”“三不愿”的问题;通过建立“助教团队”反馈不同层次学生的学习情况,较好地解决了“三不明”的问题。学生的成绩与教改前相比有明显提高。 展开更多
关键词 线上线下 s-T-s教学模式 化工原理 痛点问题
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(S,T)-WEAK TRACTABILITY OF MULTIVARIATE LINEAR PROBLEMS IN THE AVERAGE CASE SETTING 被引量:1
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作者 Yongping LIU Guiqiao XU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期1033-1052,共20页
The purpose of this article is to investigate (s, t)-weak tractability of multivariate linear problems in the average case set ting. The considered algorithms use finitely many evaluations of arbitrary linear function... The purpose of this article is to investigate (s, t)-weak tractability of multivariate linear problems in the average case set ting. The considered algorithms use finitely many evaluations of arbitrary linear functionals. Generally, we obtained matching necessary and sufficient conditions for (s,t)-weak tractability in terms of the corresponding non-increasing sequence of eigenvalues. Specifically, we discussed (s, t)-weak tractability of linear tensor product problems and obtained necessary and sufficient conditions in terms of the corresponding one-dimensional problem. As an example of applications, we discussed also (s,t)-weak tractability of a multivariate approximation problem. 展开更多
关键词 (s t)-weak TRACTABILITY LINEAR problem LINEAR tensor product problem HILBERT space AVERAGE case setting
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The Gleason's problem on normal weight general function spaces in the unit ball of C^(n)
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作者 GUO Yu-ting ZHANG Xue-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第4期604-613,共10页
In this paper,we first discuss the boundedness of certain integral operator T_(t) on the normal weight general function space F(p,μ,s)in the unit ball Bnof C^(n).As an application of this operator,we prove that the G... In this paper,we first discuss the boundedness of certain integral operator T_(t) on the normal weight general function space F(p,μ,s)in the unit ball Bnof C^(n).As an application of this operator,we prove that the Gleason’s problem is solvable on F(p,μ,s). 展开更多
关键词 Gleason's problem sOLVABILITY F(p μ s)space integral operator
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EKELAND'S PRINCIPLE FOR SET-VALUED VECTOR EQUILIBRIUM PROBLEMS 被引量:2
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作者 龚循华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1179-1192,共14页
In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we der... In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we derive an existence theorem of weakly efficient solution for set-valued vector equilibrium problems without the assumption of convexity of the constraint set and the assumptions of convexity and monotonicity of the set-valued mapping. We also obtain an existence theorem of ε-approximate solution for set-valued vector equilibrium problems without the assumptions of compactness and convexity of the constraint set. 展开更多
关键词 Ekeland's principle set-valued vector equilibrium problems weakly efficient solution c-approximate solution EXIsTENCE
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Neumann's method for boundary problems of thin elastic shells 被引量:1
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作者 Y. S. NEUSTADT 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第4期543-556,共14页
The possibility of using Neumann's method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the... The possibility of using Neumann's method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann's method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann's method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations. 展开更多
关键词 boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor
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EXISTENCE OF SOLUTIONS OF NONLOCAL PERTURBATIONS OF DIRICHLET DISCRETE NONLINEAR PROBLEMS 被引量:1
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作者 Alberto CABADA Nikolay D.DIMITROV 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期911-926,共16页
This paper is devoted to the study of second order nonlinear difference equations. A Nonlocal Perturbation of a Dirichlet Boundary Value Problem is considered. An exhaustive study of the related Green's function to t... This paper is devoted to the study of second order nonlinear difference equations. A Nonlocal Perturbation of a Dirichlet Boundary Value Problem is considered. An exhaustive study of the related Green's function to the linear part is done. The exact expression of the function is given, moreover the range of parameter for which it has constant sign is obtained. Using this, some existence results for the nonlinear problem are deduced from monotone iterative techniques, the classical Krasnoselski fixed point theorem or by application of recent fixed point theorems that combine both theories. 展开更多
关键词 Dirichlet boundary value problem nonlocal perturbations Green's function parameter dependence
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Spline Fictitious Boundary Element Alternating Method for Edge Crack Problems with Mixed Boundary Conditions 被引量:1
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作者 Z.Xu M.Chen X.M.Fan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第9期407-431,共25页
The alternating method based on the fundamental solutions of the infinite domain containing a crack,namely Muskhelishvili’s solutions,divides the complex structure with a crack into a simple model without crack which... The alternating method based on the fundamental solutions of the infinite domain containing a crack,namely Muskhelishvili’s solutions,divides the complex structure with a crack into a simple model without crack which can be solved by traditional numerical methods and an infinite domain with a crack which can be solved by Muskhelishvili’s solutions.However,this alternating method cannot be directly applied to the edge crack problems since partial crack surface of Muskhelishvili’s solutions is located outside the computational domain.In this paper,an improved alternating method,the spline fictitious boundary element alternating method(SFBEAM),based on infinite domain with the combination of spline fictitious boundary element method(SFBEM)and Muskhelishvili’s solutions is proposed to solve the edge crack problems.Since the SFBEM and Muskhelishvili’s solutions are obtained in the framework of infinite domain,no special treatment is needed for solving the problem of edge cracks.Different mixed boundary conditions edge crack problems with varies of computational parameters are given to certify the high precision,efficiency and applicability of the proposed method compared with other alternating methods and extend finite element method. 展开更多
关键词 sPLINE fictitious BOUNDARY element ALTERNATING METHOD mixed BOUNDARY conditions edge CRACK problem Muskhelishvili’s solutions stress INTENsITY factor
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Parametric Iteration Method for Solving Linear Optimal Control Problems 被引量:1
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作者 Abdolsaeed Alavi Aghileh Heidari 《Applied Mathematics》 2012年第9期1059-1064,共6页
This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of func... This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of functions which converges to the exact solution of problem. Our emphasis will be on an auxiliary parameter which directly affects on the rate of convergence. Comparison of PIM and the Variational Iteration Method (VIM) is given to show the preference of PIM over VIM. Numerical results are given for several test examples to demonstrate the applicability and efficiency of the method. 展开更多
关键词 PARAMETRIC ITERATION METHOD Optimal Control problem Pontryagin’s Maximum Principle He’s VARIATIONAL ITERATION METHOD
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Very Original Proofs of Two Famous Problems: “Are There Any Odd Perfect Numbers?” (Unsolved until to Date) and “Fermat’s Last Theorem: A New Proof of Theorem (Less than One and a Half Pages) and Its Generalization” 被引量:2
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作者 Demetrius Chr. Poulkas 《Advances in Pure Mathematics》 2021年第11期891-928,共38页
This article presents very original and relatively brief or very brief proofs about of two famous problems: 1) Are there any odd perfect numbers? and 2) “Fermat’s last theorem: A new proof of theorem and its general... This article presents very original and relatively brief or very brief proofs about of two famous problems: 1) Are there any odd perfect numbers? and 2) “Fermat’s last theorem: A new proof of theorem and its generalization”. They are achieved with elementary mathematics. This is why these proofs can be easily understood by any mathematician or anyone who knows basic mathematics. Note that, in both problems, proof by contradiction was used as a method of proof. The first of the two problems to date has not been resolved. Its proof is completely original and was not based on the work of other researchers. On the contrary, it was based on a simple observation that all natural divisors of a positive integer appear in pairs. The aim of the first work is to solve one of the unsolved, for many years, problems of the mathematics which belong to the field of number theory. I believe that if the present proof is recognized by the mathematical community, it may signal a different way of solving unsolved problems. For the second problem, it is very important the fact that it is generalized to an arbitrarily large number of variables. This generalization is essentially a new theorem in the field of the number theory. To the classical problem, two solutions are given, which are presented in the chronological order in which they were achieved. <em>Note that the second solution is very short and does not exceed one and a half pages</em>. This leads me to believe that Fermat, as a great mathematician was not lying and that he had probably solved the problem, as he stated in his historic its letter, with a correspondingly brief solution. <em>To win the bet on the question of whether Fermat was telling truth or lying, go immediately to the end of this article before the General Conclusions.</em> 展开更多
关键词 Perfect Numbers Odd Perfect Numbers Fermat’s Last Theorem Generalization of the Fermat’s Last Theorem Prime Number problems Millennium problems
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Hilbert’s First Problem and the New Progress of Infinity Theory
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作者 Xijia Wang 《Journal of Applied Mathematics and Physics》 2023年第4期891-904,共14页
In the 19th century, Cantor created the infinite cardinal number theory based on the “1-1 correspondence” principle. The continuum hypothesis is proposed under this theoretical framework. In 1900, Hilbert made it th... In the 19th century, Cantor created the infinite cardinal number theory based on the “1-1 correspondence” principle. The continuum hypothesis is proposed under this theoretical framework. In 1900, Hilbert made it the first problem in his famous speech on mathematical problems, which shows the importance of this question. We know that the infinitesimal problem triggered the second mathematical crisis in the 17-18th centuries. The Infinity problem is no less important than the infinitesimal problem. In the 21st century, Sergeyev introduced the Grossone method from the principle of “whole is greater than part”, and created another ruler for measuring infinite sets. The discussion in this paper shows that, compared with the cardinal number method, the Grossone method enables infinity calculation to achieve a leap from qualitative calculation to quantitative calculation. According to Grossone theory, there is neither the largest infinity and infinitesimal, nor the smallest infinity and infinitesimal. Hilbert’s first problem was caused by the immaturity of the infinity theory. 展开更多
关键词 Hilbert’s First problem Cardinal Numbers Method Grossone Method Continuum Paradox Infinity Theory
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A Key to Solving the Angle Trisection Problem
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第9期625-634,共10页
This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach ... This paper describes the methodology (or approach) that was key to the solution of the angle trisection problem published earlier in article entitled, “A Procedure For Trisecting An Acute Angle.” It was an approach that required first, designing a working model of a trisector mechanism, second, studying the motion of key elements of the mechanism and third, applying the fundamental principles of kinematics to arrive at the desired results. In presenting these results, since there was no requirement to provide a detailed analysis of the final construction, this information was not included. However, now that the publication is out, it is considered appropriate as well as instructive to explain more fully the mechanism analysis of the trisector in graphical detail, as covered in Section 3 of this paper, that formed the basis of the long sought solution to the age-old Angle Trisection Problem. 展开更多
关键词 Archimedes Construction College Geometry College Mathematics Angle Trisection Trisector Famous problems in Mathematics History of Mathematics Mechanism Analysis Kinematics Geometer’s sketch Pad
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Relationship between Authoritative Parenting Style and Preschool Children’s Emotion Regulation:A Moderated Mediation Model
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作者 Yan Jin Wei Chen 《International Journal of Mental Health Promotion》 2024年第3期189-198,共10页
An authoritative parenting style has been shown to promote children’s emotion regulation in European-American family studies.However,little is known about how sleep problems and the child’s sibling status in Chinese... An authoritative parenting style has been shown to promote children’s emotion regulation in European-American family studies.However,little is known about how sleep problems and the child’s sibling status in Chinese families affect this relationship.Based on family system theory,this study attempts to better understand the relationship between authoritative parenting style and emotion regulation.Mothers of preschool children in Chinese kindergartens completed questionnaires about their children’s sleep habits,their authoritative parenting styles,and children’s emotion regulation.A total of 531 children participated in this study.Results showed that authoritative parenting was positively associated with emotional regulation.Sleep problems mediated the effects of authoritative parenting style on emotion regulation.The child’s sibling status moderated the mediating effects of sleep problems in authoritative parenting and emotion regulation relationships.Specifically,the relationship between the authoritative parenting style and sleep problems was significant for only children,while birth order had no significant influence on the authoritative parenting style and sleep problems in two-child families.These findings suggest that a lowauthoritative parenting style predicts low emotion regulation through sleep problems,and this depends on the child’s sibling status,indicating that children without siblings may impair emotion regulation due to increased sleep problems. 展开更多
关键词 sleep problem emotional regulation authoritative parenting child’s sibling status preschool children
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Navier-Stokes Equations—Millennium Prize Problems 被引量:1
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作者 Asset A.Durmagambetov Leyla S.Fazilova 《Natural Science》 2015年第2期88-99,共12页
In this work, we present final solving Millennium Prize Problems formulated by Clay Math. Inst., Cambridge. A new uniform time estimation of the Cauchy problem solution for the Navier-Stokes equations is provided. We ... In this work, we present final solving Millennium Prize Problems formulated by Clay Math. Inst., Cambridge. A new uniform time estimation of the Cauchy problem solution for the Navier-Stokes equations is provided. We also describe the loss of smoothness of classical solutions for the Navier-Stokes equations. 展开更多
关键词 schrodinger’s Equation Potential scattering Amplitude Cauchy problem Navier-stokes Equations Fourier Transform The Global solvability and Uniqueness of the Cauchy problem The Loss of smoothness The Millennium Prize problems
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Random Search Algorithm for the Generalized Weber Problem
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作者 Lev Kazakovtsev 《Journal of Software Engineering and Applications》 2012年第12期59-65,共7页
In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) ... In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) and prove its efficiency for approximate solving this problem by replacing the continuous coordinate values by discrete ones. Version of the algorithm for multiprocessor systems is proposed. Experimental results for a high-performance cluster are given. 展开更多
关键词 DIsCRETE Optimization weber problem RANDOM sEARCH GENETIC Algorithms Parallel ALGORITHM
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Wavelet multiresolution interpolation Galerkin method for nonlinear boundary value problems with localized steep gradients
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作者 Xiaojing LIU Youhe ZHOU Jizeng WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第6期863-882,共20页
The wavelet multiresolution interpolation for continuous functions defined on a finite interval is developed in this study by using a simple alternative of transformation matrix.The wavelet multiresolution interpolati... The wavelet multiresolution interpolation for continuous functions defined on a finite interval is developed in this study by using a simple alternative of transformation matrix.The wavelet multiresolution interpolation Galerkin method that applies this interpolation to represent the unknown function and nonlinear terms independently is proposed to solve the boundary value problems with the mixed Dirichlet-Robin boundary conditions and various nonlinearities,including transcendental ones,in which the discretization process is as simple as that in solving linear problems,and only common two-term connection coefficients are needed.All matrices are independent of unknown node values and lead to high efficiency in the calculation of the residual and Jacobian matrices needed in Newton’s method,which does not require numerical integration in the resulting nonlinear discrete system.The validity of the proposed method is examined through several nonlinear problems with interior or boundary layers.The results demonstrate that the proposed wavelet method shows excellent accuracy and stability against nonuniform grids,and high resolution of localized steep gradients can be achieved by using local refined multiresolution grids.In addition,Newton’s method converges rapidly in solving the nonlinear discrete system created by the proposed wavelet method,including the initial guess far from real solutions. 展开更多
关键词 wavelet multiresolution interpolation transcendental nonlinearity localized steep gradient singularly perturbed boundary value problem Troesch’s problem
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Analytical Solutions of Some Two-Point Non-Linear Elliptic Boundary Value Problems
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作者 Vembu Ananthaswamy Lakshmanan Rajendran 《Applied Mathematics》 2012年第9期1044-1058,共15页
Several problems arising in science and engineering are modeled by differential equations that involve conditions that are specified at more than one point. The non-linear two-point boundary value problem (TPBVP) (Br... Several problems arising in science and engineering are modeled by differential equations that involve conditions that are specified at more than one point. The non-linear two-point boundary value problem (TPBVP) (Bratu’s equation, Troesch’s problems) occurs engineering and science, including the modeling of chemical reactions diffusion processes and heat transfer. An analytical expression pertaining to the concentration of substrate is obtained using Homotopy perturbation method for all values of parameters. These approximate analytical results were found to be in good agreement with the simulation results. 展开更多
关键词 TWO-POINT ELLIPTIC Boundary Value problems Bratu’s Equation Troesch’s problem NON-LINEAR Equations HOMOTOPY PERTURBATION Method Porous Catalyst Numerical simulation
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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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ON SOME PROBLEMS IN CHINA’S SECURITIES LEGISLATION
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作者 Gao Erson Chairman of the Research Center of International Economic Law at Nankai University Li Jiuming Li Li 《南开经济研究》 CSSCI 北大核心 1994年第S2期2-11,共10页
In May 1993, the State Council promulgated ProvisionalRegulations Regarding the Issuing of Stocks and theAdministration of Stock Dealings. However, the Stock Act isstill in the process of drafting. This paper intends ... In May 1993, the State Council promulgated ProvisionalRegulations Regarding the Issuing of Stocks and theAdministration of Stock Dealings. However, the Stock Act isstill in the process of drafting. This paper intends to discuss thefollowing three problems concerning the securities legislation. 展开更多
关键词 s sECURITIEs LEGIsLATION ON sOME problems IN CHINA CsEA
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INEXACT DAMPED NEWTON METHOD FOR NONLINEAR COMPLEMENTARITY PROBLEMS
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作者 Li Donghui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第4期487-496,共10页
In this paper, we propose an inexact damped Newtonmethod for solving nonlinear complementarity problems based on the equivalent B differentiable equations.Global convergence and locally quadratic convergence are ... In this paper, we propose an inexact damped Newtonmethod for solving nonlinear complementarity problems based on the equivalent B differentiable equations.Global convergence and locally quadratic convergence are obtained,and numerical results are given. 展开更多
关键词 Nonlinear complementarity problems Newton’s method global convergence
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