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CONVEXITY OF THE FREE BOUNDARY FOR AN AXISYMMETRIC INCOMPRESSIBLE IMPINGING JET
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作者 王晓慧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期234-246,共13页
This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provi... This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provided that the uneven ground is concave to the fluid. 展开更多
关键词 Euler system axisymmetric impinging jet INCOMPRESSIBLE free boundary convexity
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Second Note on the Definition of S<sub>1</sub>-Convexity
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作者 I. M. R. Pinheiro 《Advances in Pure Mathematics》 2015年第3期127-130,共4页
In this note, we discuss the definition of the S1-convexity Phenomenon. We first make use of some results we have attained for?? in the past, such as those contained in [1], to refine the definition of the phenomenon.... In this note, we discuss the definition of the S1-convexity Phenomenon. We first make use of some results we have attained for?? in the past, such as those contained in [1], to refine the definition of the phenomenon. We then observe that easy counter-examples to the claim extends K0 are found. Finally, we make use of one theorem from [2] and a new theorem that appears to be a supplement to that one to infer that? does not properly extend K0 in both its original and its revised version. 展开更多
关键词 Analysis convexity DEFINITION s-convexity Geometry Shape S-convexity s-Convex FUNCTION S-Convex FUNCTION
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Minima Domain Intervals and the S-Convexity, as well as the Convexity, Phenomenon
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作者 I. M. R. Pinheiro 《Advances in Pure Mathematics》 2012年第6期457-458,共2页
In this paper, we propose a refinement in the analytical definition of the s2-convex classes of functions aiming to progress further in the direction of including s2-convexity properly in the body of Real Analysis.
关键词 Analysis convexity Definition S-convexity
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First Note on the Definition of s<i>1</i>-Convexity
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作者 I. M. R. Pinheiro 《Advances in Pure Mathematics》 2014年第12期674-679,共6页
In this note, we analyze a few major claims about . As a consequence, we rewrite a major theorem, nullify its proof and one remark of importance, and offer a valid proof for it. The most important gift of this paper i... In this note, we analyze a few major claims about . As a consequence, we rewrite a major theorem, nullify its proof and one remark of importance, and offer a valid proof for it. The most important gift of this paper is probably the reasoning involved in all: We observe that a constant, namely t, has been changed into a variable, and we then tell why such a move could not have been made, we observe the discrepancy between the claimed domain and the actual domain of a supposed function that is created and we then explain why such a function could not, or should not, have been created, along with others. 展开更多
关键词 Analysis convexity DEFINITION S-convexity GEOMETRY
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MONOTONICITY,CONVEXITY AND INEQUALITIES INVOLVING THE GENERALIZED ELLIPTIC INTEGRALS 被引量:3
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作者 王淼坤 张稳 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1440-1450,共11页
We establish the monotonicity and convexity properties for several special functions involving the generalized elliptic integrals, and present some new analytic inequalities.
关键词 Gaussian HYPERGEOMETRIC function generalized ELLIPTIC INTEGRALS convexity inequality
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NORMAL STRUCTURE AND SOME GEOMETRIC PARAMETERS RELATED TO THE MODULUS OF U-CONVEXITY IN BANACH SPACES 被引量:2
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作者 Ji Gao Satit Saejung 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1035-1040,共6页
We present a short and simple proof of the recent result of Yang and Wang [12]. Stimulated by their idea, two geometric parameters Uax(ε) and βx (ε), both related to Gao's modulus of U-convexity of a Banach sp... We present a short and simple proof of the recent result of Yang and Wang [12]. Stimulated by their idea, two geometric parameters Uax(ε) and βx (ε), both related to Gao's modulus of U-convexity of a Banach space X, are introduced. Their properties and the relationships with normal structure are studied. Some existing results involving normal structure and fixed points for non-expansive mappings in Banach spaces are improved. 展开更多
关键词 uniform normal structure modulus of convexity ULTRAPOWER
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基于Convexity模型的航空公司利率风险管理
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作者 金永利 《中国民航学院学报》 2005年第5期1-6,共6页
国际性特征日趋明显的中国航空公司正面临着金融市场上的诸多不确定性,其中利率风险日益凸显。将Convexity模型这一在西方发达国家较为成熟的风险管理工具引入中国,并将其应用到中国航空公司的风险管理实践,对利率风险进行了极为精确的... 国际性特征日趋明显的中国航空公司正面临着金融市场上的诸多不确定性,其中利率风险日益凸显。将Convexity模型这一在西方发达国家较为成熟的风险管理工具引入中国,并将其应用到中国航空公司的风险管理实践,对利率风险进行了极为精确的量化评估,最后给出了相应的规避方法。 展开更多
关键词 风险管理 利率风险评估 convexity模型 航空公司
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THE MODULUS OF CONVEXITY AND THE EQUIVALENT CONDITIONS OF UNIFORMLY NON-SQUARE SPACES
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作者 韩瑞珠 《Journal of Southeast University(English Edition)》 EI CAS 1989年第1期15-20,共6页
This paper shows that X is uniformly non-square iff P(η_o)】0 for someη_o∈(0,2).Thus X is super-reflexive if and only if for X there exists an equivalent normwhich meets the above condition.By virtue of the before ... This paper shows that X is uniformly non-square iff P(η_o)】0 for someη_o∈(0,2).Thus X is super-reflexive if and only if for X there exists an equivalent normwhich meets the above condition.By virtue of the before mentioned result,the author derives the necessary,and suffi-cient conditions for X and l^p(X_j)being uniformly non-square,respectively,and gives acharacterization of finite-dimensional spaces which are uniformly non-square. 展开更多
关键词 MODULUS convexity/uniformly non-square SPACE super-reflexive SPACE
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Characterization of Uniform PL-convexity of Complex Banach Space by Functions with Two Variables
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作者 HUANG Hai jun,LIU Pei de (College of Mathematics and Computer Science, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第4期399-403,共5页
We give a new characterization ofq-uniform PL-convexity of complex Banach space by using the existence of a kind of functions with two variables and then prove a sharp weak (1, 1)-type inequality for analytic martinga... We give a new characterization ofq-uniform PL-convexity of complex Banach space by using the existence of a kind of functions with two variables and then prove a sharp weak (1, 1)-type inequality for analytic martingales with values in the Banach space. 展开更多
关键词 analytic martingale uniform PL convexity mean square operator
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Convexity and Positivity of Bivariate Quadratic Bézier Surfaces over a Rectangle
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作者 DING You dong School of Computer Engineering and Science, Shanghai University, Shanghai 200072, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第1期20-28,共9页
With the help of several discriminants about the zero points of a quartic polynomial, the sufficient and necessary conditions for the positivity and nonnegativity of the quartic polynomial over an interval I(-∞,+... With the help of several discriminants about the zero points of a quartic polynomial, the sufficient and necessary conditions for the positivity and nonnegativity of the quartic polynomial over an interval I(-∞,+∞) was derived. Based on these conclusions, the sufficient and necessary conditions for the positivity and convexity of the 2×2 Bézier surface over a rectangle were obtained. A simple sufficient condition was deduced also and finally several examples were given. 展开更多
关键词 Bézier surface convexity POSITIVITY DISCRIMINANT
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ON A GENERALIZED MODULUS OF CONVEXITY AND UNIFORM NORMAL STRUCTURE
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作者 杨长森 王丰辉 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期838-844,共7页
In this article, the authors study a generalized modulus of convexity, δ(α) (ε). Certain related geometrical properties of this modulus are analyzed. Their main result is that Banach space X has uniform normal ... In this article, the authors study a generalized modulus of convexity, δ(α) (ε). Certain related geometrical properties of this modulus are analyzed. Their main result is that Banach space X has uniform normal structure if there exists ε, 0 ≤e≤ 1, such that δ^(α)(1+ε ) 〉 (1- α)ε. 展开更多
关键词 Generalized modulus of convexity uniform normal structure ULTRAPRODUCT
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The Optimality Conditions for Multiobjective Semi-infinite Programming Involving Generalized Unified (C, α, p, d)-convexity
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作者 ZHANG Qing-xiang ZHANG Yong-zhan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期241-249,共9页
The definition of generalized unified (C, α, ρ, d)-convex function is given. The concepts of generalized unified (C, α, ρ, d)-quasiconvexity, generalized unified (C, α, ρ, d)-pseudoconvexity and generalized unif... The definition of generalized unified (C, α, ρ, d)-convex function is given. The concepts of generalized unified (C, α, ρ, d)-quasiconvexity, generalized unified (C, α, ρ, d)-pseudoconvexity and generalized unified (C, α, ρ, d)-strictly pseudoconvex functions are presented. The sufficient optimality conditions for multiobjective nonsmooth semi-infinite programming are obtained involving these generalized convexity lastly. 展开更多
关键词 generalized convexity multiobjective semi-infinite programming efficient solution optimality conditions
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Stratified Convexity &Concavity of Gradient Flows on Manifolds with Boundary
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作者 Gabriel Katz 《Applied Mathematics》 2014年第17期2823-2848,共26页
As has been observed by Morse [1], any generic vector field v on a compact smooth manifold X with boundary gives rise to a stratification of the boundary by compact submanifolds , where . Our main observation is that ... As has been observed by Morse [1], any generic vector field v on a compact smooth manifold X with boundary gives rise to a stratification of the boundary by compact submanifolds , where . Our main observation is that this stratification re-flects the stratified convexity/concavity of the boundary ?with respect to the ?v-flow. We study the behavior of this stratification under deformations of the vector field v. We also investigate the restrictions that the existence of a convex/concave traversing ?v-flow imposes on the topology of X. Let be the orthogonal projection of on the tangent bundle of . We link the dynamics of theon the boundary with the property of in X being convex/concave. This linkage is an instance of more general phenomenon that we call “holography of traversing fields”—a subject of a different paper to follow. 展开更多
关键词 MORSE Theory Gradient FLOWS convexity CONCAVITY MANIFOLDS with Boundary
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BERNSTEIN-TYPE OPERATORS, CONVEXITY AND LIPSCHITZ CLASSES
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作者 B. Delia Vecchia I. Rasa 《Analysis in Theory and Applications》 1995年第1期16-23,共8页
In the present paper we extend previous results about the monotoaicity of Bernstein-type operators rdtiwe to convex functions and about the preservation of Lipschitz classes.
关键词 BERNSTEIN-TYPE OPERATORS convexity AND LIPSCHITZ CLASSES
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On the Convexity of Generalized Grotzsch Ring Function
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作者 WANGGen-di QIUSong-liang 《杭州电子科技大学学报(自然科学版)》 2005年第2期88-91,共4页
In this paper,the authors study the monotoneity and convexity of certain combinations and composites defined in terms of the generalized Grotzsch ring function μa (r), which appears in Ramanujan' s generalized mo... In this paper,the authors study the monotoneity and convexity of certain combinations and composites defined in terms of the generalized Grotzsch ring function μa (r), which appears in Ramanujan' s generalized modular equations,and obtain some inequalities for this function. 展开更多
关键词 Ramanujan' s MODULAR equation GENERALIZED Grotzsch RING function monotoneity convexity INEQUALITIES
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A Sufficient Convexity Condition for Parametric Bézier Surface over Rectangle
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作者 Sai Hao Xianghuai Dong 《American Journal of Computational Mathematics》 2020年第2期252-265,共14页
Surface convexity is a key issue in computer aided geometric design, which is widely applied in geometric modeling field, such as physical models, industrial design, automatic manufacturing, etc. In this paper, a suff... Surface convexity is a key issue in computer aided geometric design, which is widely applied in geometric modeling field, such as physical models, industrial design, automatic manufacturing, etc. In this paper, a sufficient convexity condition of the parametric Bézier surface over rectangles is proposed, which is firstly considered as a sufficient convexity condition for the Bézier control grid. The condition is proved by De Casteljau surface subdivision arithmetic, in which the recursive expressions elaborate that the control grid eventually converges to the surface. At last, two examples for the modeling of interpolation-type surface are discussed, one of which is a general surface and the other is a degenerate surface. 展开更多
关键词 convexity Condition Bézier Surface De Casteljau Arithmetic Interpolation-Type Surface
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Schur Convexity and the Dual Simpson’s Formula
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作者 Yaowen Li 《Journal of Applied Mathematics and Physics》 2016年第4期623-629,共7页
In this paper, we show that some functions related to the dual Simpson’s formula and Bullen- Simpson’s formula are Schur-convex provided that f is four-convex. These results should be compared to that of Simpson’s ... In this paper, we show that some functions related to the dual Simpson’s formula and Bullen- Simpson’s formula are Schur-convex provided that f is four-convex. These results should be compared to that of Simpson’s formula in Applied Math. Lett. (24) (2011), 1565-1568. 展开更多
关键词 Schur convexity 4-Convex Function Dual Simpson’s Formula Bullen-Simpson’s Formula
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Convexity Properties for a Function of Two Integer Variables
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作者 Sara Nourazari Hillel Kumin 《American Journal of Operations Research》 2021年第6期253-256,共4页
Sufficient conditions are given for any local minimum of a function of two integer variables to be a global minimum. An example is given </span><span style="font-family:Verdana;">to</span>&... Sufficient conditions are given for any local minimum of a function of two integer variables to be a global minimum. An example is given </span><span style="font-family:Verdana;">to</span><span style="font-family:Verdana;"> show that a function of two integer variables need not be discrete convex for this condition to hold. 展开更多
关键词 Linear Integer Programming convexity
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ANALYSIS SOLUTION OF BULGING CONVEXITY OF THE HYDRAULIC ELASTIC BULGING ROLL 被引量:2
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作者 Li Benli Wang Bingru +2 位作者 Liu Zhubai Liu Guohui (Northeast Heavy Machinery institute)Li Yunquan Li Zhongli(Xi’an Heavy Machine Plant) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1994年第3期198-200,2017686202+2,共17页
The hydraulic elastic bulging roll system is a new roll system being developed in recent years.It is the first time in home that dead load test and study on this system has been made.Based on the experiment,the analys... The hydraulic elastic bulging roll system is a new roll system being developed in recent years.It is the first time in home that dead load test and study on this system has been made.Based on the experiment,the analysis solution of the bulging convexity of the hydraulic elastic bulging roll was obtained by selecting appropriate displacement function and adopting inverse solution of the elasticity theory.In evaluating,a variable displacement function and its solving method was advanced.The analysis results are in accord with the experiment's.Some conclusions have laid the foundation of establishing close-loop controlled mathematical model of the hydraulic elastic bulging roll system. 展开更多
关键词 Bulging convexity Hydraulic elastic buiging roll Analysis solution
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THE SCHUR HARMONIC CONVEXITY FOR A CLASS OF SYMMETRIC FUNCTIONS 被引量:13
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作者 褚玉明 孙天川 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1501-1506,共6页
In this article, we prove that the symmetric function Fn(x,r)=∑i1+i2+……in=r(x1(i1x2^i2……xn^in)1/r is Schur harmonic convex for x ∈ R+n and r ∈N -=(1, 2, 3,...} As its applications, some analytic inequa... In this article, we prove that the symmetric function Fn(x,r)=∑i1+i2+……in=r(x1(i1x2^i2……xn^in)1/r is Schur harmonic convex for x ∈ R+n and r ∈N -=(1, 2, 3,...} As its applications, some analytic inequalities are established. 展开更多
关键词 symmetric function Schur convex Schur harmonic convex
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