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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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The Shaping of Woman's Language and Its Therapeutic Function through Images in "The Yellow Wallpaper"
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作者 袁芳 《科技信息》 2011年第27期194-194,共1页
In Perkins' "The Yellow Wallpaper",the wallpaper acts as woman's language.Through this interaction between the wallpaper and the heroine in in this story,Gilman displays to us women's embarrassin... In Perkins' "The Yellow Wallpaper",the wallpaper acts as woman's language.Through this interaction between the wallpaper and the heroine in in this story,Gilman displays to us women's embarrassing status in family and society,and leaves the reader to think of woman's future. 展开更多
关键词 英语教学 教学方法 阅读教学 翻译教学
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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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EXISTENCE OF SOLUTION FOR BOUNDARY VALUE PROBLEM OF NONLINEAR FRACTIONAL DIFFERENTIAL EQUATION 被引量:10
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作者 Su Xinwei Liu Landong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第3期291-298,共8页
This paper is concerned with the boundary value problem of a nonlinear fractional differential equation. By means of Schauder fixed-point theorem, an existence result of solution is obtained.
关键词 fractional differential equation boundary value problem Caputo's fractional derivative schauder fixed-point theorem.
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A NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL EXISTENCE OF CLASSICAL SOLUTIONS TO CAUCHY PROBLEM OF QUASILINEAR HYPERBOLIC SYSTEMS IN DIAGONAL FORM 被引量:1
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作者 郑永树 刘法贵 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期571-576,共6页
This article considers Cauchy problem for quasilinear hyperbolic systems in diagonal form. A necessary and sufficient condition in guaranteeing that Cauchy problem admits a unique global classical solution on t ≥ 0 i... This article considers Cauchy problem for quasilinear hyperbolic systems in diagonal form. A necessary and sufficient condition in guaranteeing that Cauchy problem admits a unique global classical solution on t ≥ 0 is obtained, and a sharp estimate of the life span for the classical solution is given. 展开更多
关键词 Cauchy problem global classical solution BLOW-UP life s
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(r, s)-STABILITY OF UNFOLDING OF г-EQUIVARIANT BIFURCATION PROBLEM 被引量:1
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作者 刘恒兴 张敦穆 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期408-418,共11页
In this paper,the (?)-equivariant (s, t)-equivalence relation and (?)-equivariant infinitesimally (r, s)-stability of (?)-equivariant bifurcation problem are defined. The criterion for (?)-equivariant infinitesimally ... In this paper,the (?)-equivariant (s, t)-equivalence relation and (?)-equivariant infinitesimally (r, s)-stability of (?)-equivariant bifurcation problem are defined. The criterion for (?)-equivariant infinitesimally (r, s)-stability is proven when (?) is a compact finite Lie group .Transversality condition is used to characterize the stability. 展开更多
关键词 г-equivariant bifurcation problem UNFOLDING TRANsVERsALITY г-equivariant infinitesimally (r s)-stability г-equivariant (r s)-equivalence.
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Ureteral Ewing’s sarcoma in an elderly woman: A case report 被引量:2
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作者 Xin-Xin Li Jian-Bin Bi 《World Journal of Clinical Cases》 SCIE 2019年第20期3372-3376,共5页
BACKGROUND Ewing’s sarcoma(ES)is regarded as a skeletal tumor,with few instances of extraskeletal ES.A primary ES in the ureter is extremely rare.CASE SUMMARY We report the case of a 69-year-old woman who presented w... BACKGROUND Ewing’s sarcoma(ES)is regarded as a skeletal tumor,with few instances of extraskeletal ES.A primary ES in the ureter is extremely rare.CASE SUMMARY We report the case of a 69-year-old woman who presented with intermittent flank pain and hematuria and was found to have a mass in the left ureter.Pathology of the excised mass indicated ES.The clinical treatment and pathologic characteristics in this case,and a review of the literature describing ES in the urinary system,are presented.CONCLUSION Due to the rarity and malignancy of ES in ureter,early diagnosis and prompt surgical treatment are critical. 展开更多
关键词 Ewing’s sARCOMA URETER ELDERLY woman FLANK pain HEMATURIA Case report
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A Solution to the Famous “Twin’s Problem” 被引量:2
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作者 Prodromos Char. Papadopoulos 《Advances in Pure Mathematics》 2019年第9期794-826,共33页
In the following pages I will try to give a solution to this very known unsolved problem of theory of numbers. The solution is given here with an important analysis of the proof of formula (4.18), with the introductio... In the following pages I will try to give a solution to this very known unsolved problem of theory of numbers. The solution is given here with an important analysis of the proof of formula (4.18), with the introduction of special intervals between square of prime numbers that I call silver intervals . And I make introduction of another also new mathematic phenomenon of logical proposition “In mathematics nothing happens without reason” for which I use the ancient Greek term “catholic information”. From the theorem of prime numbers we know that the expected multitude of prime numbers in an interval is given by formula ?considering that interval as a continuous distribution of real numbers that represents an elementary natural numbers interval. From that we find that in the elementary interval around of a natural number ν we easily get by dx=1 the probability that has the ν to be a prime number. From the last formula one can see that the second part of formula (4.18) is absolutely in agreement with the above theorem of prime numbers. But the benefit of the (4.18) is that this formula enables correct calculations in set N on finding the multitude of twin prime numbers, in contrary of the above logarithmic relation which is an approximation and must tend to be correct as ν tends to infinity. Using the relationship (4.18) we calculate here the multitude of twins in N, concluding that this multitude tends to infinite. But for the validity of the computation, the distribution of the primes in a random silver interval is examined, proving on the basis of catholic information that the density of primes in the same random silver interval is statistically constant. Below, in introduction, we will define this concept of “catholic information” stems of “information theory” [1] and it is defined to use only general forms in set N, because these represent the set N and not finite parts of it. This concept must be correlated to Riemann Hypothesis. 展开更多
关键词 Twin problem Twin’s problem Unsolved Mathematical problems Prime NUMBER problems Millennium problems Riemann HYPOTHEsIs Rie-mann’s HYPOTHEsIs NUMBER THEORY Information THEORY Probabilities statistics
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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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Feminism, Patriarchy and Culture Dominance ——A review to "The Woman Warrior
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作者 罗军荣 《广西师范大学学报(哲学社会科学版)》 2002年第S3期13-20,共8页
The Woman Warrior" is an influential book in the 20th century making a thunder of voice in the world to accuse the stereotype of patriarchy and racism, which also shows the Chinese Americans’ difficulty of being... The Woman Warrior" is an influential book in the 20th century making a thunder of voice in the world to accuse the stereotype of patriarchy and racism, which also shows the Chinese Americans’ difficulty of being edged to the cultural cliff. This article analyses the content and the style of the novel to see inside what the writer wants to express and to figure out the real reason of the inequality between sexes and reveal the truth of the western culture dominance. Feminism, Patriarchy and culture are the main factors considered in the article. 展开更多
关键词 FEMINIsM PATRIARCHY woman’s status ORIENTAL MYTH cross CULTURE living
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part III. An Original Solution of Hilbert’s Fourth Problem 被引量:3
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第3期283-293,共11页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geom... This article refers to the “Mathematics of Harmony” by Alexey Stakhov [1], a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries—New Geometric Theory of Phyl-lotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci -Goniometry ( is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scien-tific ideas—The “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—The “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclid’s Fifth Postulate Lobachevski’s GEOMETRY HYPERBOLIC GEOMETRY Phyllotaxis Bodnar’s GEOMETRY Hilbert’s FOURTH problem the “Golden” and “Metallic” Means Binet Formulas HYPERBOLIC FIBONACCI and Lucas Functions Gazale Formulas “Golden” FIBONACCI -Goniometry
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Comprehensive form of solution for Lamb's dynamic problem expressed by Green's functions 被引量:1
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作者 丁伯阳 徐庭 +1 位作者 陈军 欧阳明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第12期1543-1552,共10页
By the analysis for the vectors of a wave field in the cylindrical coordinate and Sommerfeld's identity as well as Green's functions of Stokes' solution pertaining the conventional elastic dynamic equation, the res... By the analysis for the vectors of a wave field in the cylindrical coordinate and Sommerfeld's identity as well as Green's functions of Stokes' solution pertaining the conventional elastic dynamic equation, the results of Green's function in an infinite space of an axisymmetric coordinate are shown in this paper. After employing a supplementary influence field and the boundary conditions in the free surface of a senti-space, the authors obtain the solutions of Green's function for Lamb's dynamic problem. Besides, the vertical displacement uzz and the radial displacement urz can match Lamb's previous results, and the solutions of the linear expansion source u^r and the linear torsional source uee are also given in the paper. The authors reveal that Green's function of Stokes' solution in the semi-space is a comprehensive form of solution expressing the dynamic Lamb's problem for various situations. It may benefit the investigation of deepening and development of Lamb's problems and solution for pertinent dynamic problems conveniently. 展开更多
关键词 Lamb's problem Green's function comprehensive form of solution
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关于Knight’s Tour Problem的图论解法
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作者 吴英 李传文 马军生 《兰州工业高等专科学校学报》 2006年第3期40-43,共4页
通过分析欧拉所给出Knight’s Tour Problem的解法,结合哈密尔顿路和哈密尔顿圈的相关知识,得出其解法对应着二部图中的一条哈密尔顿圈.由此再充分利用8×8棋盘所对应的8×8表格的对称性及同格图的特性,对欧拉所给出的Knight’s... 通过分析欧拉所给出Knight’s Tour Problem的解法,结合哈密尔顿路和哈密尔顿圈的相关知识,得出其解法对应着二部图中的一条哈密尔顿圈.由此再充分利用8×8棋盘所对应的8×8表格的对称性及同格图的特性,对欧拉所给出的Knight’s Tour Problem的解法作了进一步的探讨,得出了以欧拉的解法为基础的以任一棋格为骑士周游起点的另外一系列解法.最后,把Knight’sTour Problem推广到m×n棋盘上,考虑到移动规则的特殊性,利用图论的相关知识,得到3×4,8×16和16×16棋盘上的Knight’s Tour Problem的解法,同时给出8m×8n(m>2,n>2)棋盘上Knight’s Tour Problem的猜想. 展开更多
关键词 Knight’s TOUR problem 哈密尔顿路 哈密尔顿圈 同构图 图的对称性
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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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Clarifications for the Published Article: “A Solution to the Famous Twin’s Problem” in the APM of SCIRP at 24 September of 2019 被引量:1
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作者 Prodromos Char. Papadopoulos 《Advances in Pure Mathematics》 2020年第9期547-587,共41页
This article B is almost autonomous because it can be read independently from the first published article A [1] using only a few parts of the article A. Be-low are given instructions so to need the reader study only o... This article B is almost autonomous because it can be read independently from the first published article A [1] using only a few parts of the article A. Be-low are given instructions so to need the reader study only on few places of the article A. Also, in the part A of Introduction, here, you will find simple and useful definitions and the strategy we are going to follow as well useful new theorems (also and in Section 5, which have been produced in this solution). So the published solution of twin’s problem can now be easily understood. The inequalities (4.17), (4.18) of Article A are proved here in Section 4 by a new clear method, without the possible ambiguity of the text between the relations (4.14), (4.16) of the Article A. Also we complete the proof for the twin’s distri-bution which we use. At the end here are presented the Conclusions, the No-menclatures and the numerical control of the proof, which is probably useful as well in coding methods. For a general and convincing picture is sufficient, a study from the beginning of this article B until the end of the part A of the In-troduction here as well a general glance on the Section 5 and on the Conclu-sions below. 展开更多
关键词 Twin problem Twin’s problem Unsolved Mathematical problems Prime Number problems Millennium problems Riemann Hypothesis Riemann’s Hypothesis Number Theory Information Theory Probabilities statistics
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GLEASON’S PROBLEM ON FOCK-SOBOLEV SPACES 被引量:1
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作者 Jineng DAI Jingyun ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2021年第1期337-348,共12页
In this article,we solve completely Gleason’s problem on Fock-Sobolev spaces Fp,m for any non-negative integer m and 0<p≤∞.
关键词 Fock-sobolev space Gleason’s problem
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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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The second Eshelby problem and its solvability 被引量:1
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作者 Wen-Nan Zou Quan-Shui Zheng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第5期1331-1333,共3页
It is still a challenge to clarify the dependence of overall elastic properties of heterogeneous materials on the microstructures of non-elliposodal inhomogeneities (cracks, pores, foreign particles). From the theor... It is still a challenge to clarify the dependence of overall elastic properties of heterogeneous materials on the microstructures of non-elliposodal inhomogeneities (cracks, pores, foreign particles). From the theory of elasticity, the formulation of the perturbance elastic fields, coming from a non-ellipsoidal inhomogeneity embedded in an infinitely extended material with remote constant loading, inevitably involve one or more integral equations. Up to now, due to the mathematical difficulty, there is almost no explicit analytical solution obtained except for the ellipsoidal inhomo- geneity. In this paper, we point out the impossibility to trans- form this inhomogeneity problem into a conventional Eshelby problem by the equivalent inclusion method even if the eigenstrain is chosen to be non-uniform. We also build up an equivalent model, called the second Eshelby problem, to investigate the perturbance stress. It is probably a better template to make use of the profound methods and results of conventional Eshelby problems of non-ellipsoidal inclusions. 展开更多
关键词 The second Eshelby's problem Linear elasticity Non-ellipsoidal inhomogeneity Overall elastic proper-ties
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Existence of Positive Solutions for a Third-Order Multi-Point Boundary Value Problem 被引量:2
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作者 A. Guezane-Lakoud L. Zenkoufi 《Applied Mathematics》 2012年第9期1008-1013,共6页
By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous ... By using Leray-Schauder nonlinear alternative, Banach contraction theorem and Guo-Krasnosel’skii theorem, we discuss the existence, uniqueness and positivity of solution to the third-order multi-point nonhomogeneous boundary value problem (BVP1): where for The interesting point lies in the fact that the nonlinear term is allowed to depend on the first order derivative . 展开更多
关键词 Guo’s Fixed POINT THEOREM Three POINT Boundary Value problem Positive solution LERAY sCHAUDER Non-Linear Alternative CONTRACTION Principle
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