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组合同伦内点算法求解一类非凸无界优化问题 被引量:2
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作者 蔡志丹 赵立芹 苏孟龙 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第6期1073-1076,共4页
用组合同伦内点算法求解一类非凸无界优化问题,在适当的条件下得到了同伦路径的存在性.结果表明,沿着此同伦路径跟踪,即可得到非凸优化问题的K-K-T点.
关键词 优化问题 同伦路径 全局收敛算法
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矢状面骶骨铅垂线与远端融合椎的距离在青少年特发性脊柱侧凸术后发生交界性后凸的临床意义 被引量:10
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作者 易红蕾 韦葛堇 +3 位作者 魏显招 王飞 蓝思彬 段明阳 《颈腰痛杂志》 2017年第1期14-17,共4页
目的明确矢状面骶骨后上角铅垂线与远端融合椎的距离在青少年特发性脊柱侧凸融合节段选择中的意义。方法回顾性分析165例从2005至2008年接受后路椎弓根螺钉固定矫形手术的AIS患者。排除标准:非特发性脊柱侧凸,下端融合椎低于L4,前后路... 目的明确矢状面骶骨后上角铅垂线与远端融合椎的距离在青少年特发性脊柱侧凸融合节段选择中的意义。方法回顾性分析165例从2005至2008年接受后路椎弓根螺钉固定矫形手术的AIS患者。排除标准:非特发性脊柱侧凸,下端融合椎低于L4,前后路联合手术,后路钉钩混合手术,翻修手术,影像学资料不完整。共有88例纳入,分为三组,PJK(Proximal Junctional Kyphosis)组,DJK(Distal Junctional Kyphosis)组,对照组。PJK定义为融合节段最上端的椎体(UIV,Upper instrumented vertebrae)的下终板和其近端相邻第二个椎体的上终板延长线的夹角改变大于10°。DJK定义为远端融合椎(LIV,lowest intrumented vertebrae)上终板到远端融合椎相邻一个椎体的下终板之间的角度改变大于5°。选择没有其他任何并发症的病人作为对照组。比较三组之间年龄、Risser征、上胸弯、主胸弯、矢状面胸椎后凸、腰椎前凸以及远端融合椎和矢状面骶骨铅垂线(SSVL,sagittal Sacral Vertical Line)的距离。结果其中15例在随访中发生近端交界性后凸畸形,列为PJK组。8例发生远端交界性后凸,列为DJK组。将36例无其他任何并发症的随访超过2年的病人作为对照组。PJK组、DJK组和对照组三组在术前胸椎后凸、腰椎前凸及术后胸椎后凸、腰椎前凸及矢状面矫正度数的差值上均没有显著差异(P>0.05)。但是PJK组年龄及Risser征均较对照组小,冠状面主胸弯及近胸弯角度均较对照组小,而且术前矢状面近端后凸角度较对照组大,有统计学意义(P<0.05)。LIV和SSVL在术后和末次随访之间的距离PJK,DJK和C组之间是明显不同的。当LIV的中点落于SSVL线腹侧容易出现PJK,而LIV位于SSVL线的背侧时,则容易出现DJK。结论如果下端椎位于矢状面骶骨铅垂线腹侧,可能增加近端交界性后凸的风险,相反,如果位于矢状面骶骨铅垂线背侧,容易继发远端交界性后凸。所以,术后下端椎与矢状面骶骨铅垂线可能预测近端或远端交界性后凸的发生。 展开更多
关键词 青少年特发性脊柱侧 矢状面骶骨铅垂线 远端融合椎 近端交性后 远端交 性后
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同伦内点方法求解一类无界非凸集合上的不动点问题
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作者 苏孟龙 赵立芹 吕显瑞 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2011年第5期839-843,共5页
给出了求解一类无界非凸集上不动点问题的同伦内点方法.利用自映射Φ(x),并结合约束函数的梯度,先构造一组无界性条件,在此基础上,给出了不动点存在性的构造性证明,得到了同伦内点方法的全局收敛性.
关键词 同伦内点方法 全局收敛性方法
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随机利率下现值函数的极限分布及其上、下界
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作者 张奕 肖华燕 《科技通报》 2006年第4期431-436,共6页
考虑在随机利率情形下由n个同质的被保人所组成的终身寿险组合的现值函数。在各被保人的未来余命随机变量相互独立的情形下,得到了现值函数的极限分布。并进一步考虑采用Dhaene等人所研究的Comonotonicity方法,给出了现值函数极限分布... 考虑在随机利率情形下由n个同质的被保人所组成的终身寿险组合的现值函数。在各被保人的未来余命随机变量相互独立的情形下,得到了现值函数的极限分布。并进一步考虑采用Dhaene等人所研究的Comonotonicity方法,给出了现值函数极限分布的上、下凸界。文章最后给出了一个数值模拟说明其主要结果。 展开更多
关键词 终身寿险组合 现值 强大数律 凸界
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无界凸多面体由“和形式”向“交形式”的转化 被引量:4
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作者 魏权龄 汪俊 闫洪 《系统工程理论与实践》 EI CSCD 北大核心 2004年第3期87-90,共4页
凸多面体可以表示成一组线性不等式的交 ,称这种表示为凸多面体的“交形式”;同时 ,它也可以由其全部极点和对应的凸多面锥的全部极方向生成 ,称之为“和形式”.将一个凸多面体在“和形式”与“交形式”之间进行转化是数学规划中的一个... 凸多面体可以表示成一组线性不等式的交 ,称这种表示为凸多面体的“交形式”;同时 ,它也可以由其全部极点和对应的凸多面锥的全部极方向生成 ,称之为“和形式”.将一个凸多面体在“和形式”与“交形式”之间进行转化是数学规划中的一个基本问题 .本文使用类似线性规划中的“大 M-方法”,构造性地将无界凸多面体“和形式”的凸多面体转化为“交形式”,并用数值例子说明了该算法的应用过程 . 展开更多
关键词 多面体 “和形式” “交形式” 数学规划
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GL(2)上p幂扭L函数的Weyl型混合界
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作者 高正霄 罗姝 齐治 《中国科学:数学》 CSCD 北大核心 2024年第4期593-616,共24页
设g是给定的具有任意级与邻类的全纯尖形式.设χ是模q=p^(γ)的本原特征.对于任意ε>0,本文证明了如下Weyl型混合亚凸界:L(1/2+it,g■χ)■_(g,p,ε)((1+|t|)q)^(1/3+ε).
关键词 L函数 凸界 Besselδ方法
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无界凸集性质的一个注记
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作者 邓群 《重庆师范学院学报(自然科学版)》 1996年第4期67-69,共3页
对文献[1]中有关无界凸性的三个性质给出了新的证明
关键词 吸收锥
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K - Bounded Sets and A - Spaces 被引量:2
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作者 武俊德 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期64-66, ,共3页
Let E and F be two vector spaces in duality with respect to the bilinear pairing 〈,〉. The weak (Mackey,strong) topology on E will be denoted by σ(E,F) (τ(E,F),β(E,F)). In this paper,we show that AE is σ(E,F) K b... Let E and F be two vector spaces in duality with respect to the bilinear pairing 〈,〉. The weak (Mackey,strong) topology on E will be denoted by σ(E,F) (τ(E,F),β(E,F)). In this paper,we show that AE is σ(E,F) K bounded subset if and only if A is β(E,F) K bounded subset. If τ(E′,E) is a quasi barrelled space,we also give a few characterizations for (E,T) to be A space. 展开更多
关键词 locally convex space K-bounded set A-space
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基于污染Gamma分布的聚合风险模型及其在风险分类中的应用 被引量:2
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作者 卢志义 刘乐平 孟生旺 《系统科学与数学》 CSCD 北大核心 2009年第2期174-183,共10页
分析了污染Gamma分布及其性质,讨论了基于污染Gamma分布的聚合风险模型.对模型的概率特性和参数估计进行了分析,并对该模型在风险分类中的应用进行了讨论.为克服索赔总量的分布函数在计算上的困难,利用同单调性理论得到了随机凸序意义... 分析了污染Gamma分布及其性质,讨论了基于污染Gamma分布的聚合风险模型.对模型的概率特性和参数估计进行了分析,并对该模型在风险分类中的应用进行了讨论.为克服索赔总量的分布函数在计算上的困难,利用同单调性理论得到了随机凸序意义下索赔总量随机变量S的随机上界S^c,对S^c的分布函数及限额损失保费进行了讨论.通过一个例子对所述结论的有效性进行验证. 展开更多
关键词 污染Gamma分布 聚合风险模型 风险分类 同单调性 随机凸界.
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On Drop and Weak Drop Properties for Bounded Closed Convex Sets*
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作者 张子厚 《Journal of Mathematical Research and Exposition》 CSCD 1999年第4期667-672,共6页
In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to ... In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to have the drop and weak dropproperties. 展开更多
关键词 Bounded closed convex set drop property weak drop property.
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On Characterization of Iterative Approximation for Asymptotically Pseudocontractive Mappings
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作者 曾六川 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2005年第2期279-286,共8页
Let C be a nonempty bounded closed convex subset of a Banach space X, and T : C → C be uniformly L-Lipschitzian with L ≥ 1 and asymptotically pseudocontractive with a sequence {kn}(?)[1, ∞), limn→∞ kn = 1. Fix u ... Let C be a nonempty bounded closed convex subset of a Banach space X, and T : C → C be uniformly L-Lipschitzian with L ≥ 1 and asymptotically pseudocontractive with a sequence {kn}(?)[1, ∞), limn→∞ kn = 1. Fix u ∈ C. For each n ≥ 1, xn is a unique fixed point of the contraction Sn(x) = (1 - (tn)/(Lkn))u + (tn)/(Lkn)Tnx(?)x ∈ C, where {tn}(?)[0,1). Under suitable conditions, the strong convergence of the sequence{xn}to a fixed point of T is characterized. 展开更多
关键词 fixed point asymptotically pseudocontractive mapping uniform Lipschitzian mapping uniform normal structure Banach contraction principle.
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ON THE EXISTENCE OF FIXED POINTS FOR LIPSCHITZIAN SEMIGROUPS IN BANACH SPACES 被引量:1
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作者 ZENG LUCHUAN, YANG YALI Department of Matematics, Shanghai Normal University, Shanghai 200234, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第3期397-404,共8页
Let C be a nonempty bounded subset of a p-uniformly convex Banach space X, and T = {T(t): t S} be a Lipschitzian semigroup on C with lim inf |||T(t)||| < Np, where Np is n→ t s the normal structure coefficient of ... Let C be a nonempty bounded subset of a p-uniformly convex Banach space X, and T = {T(t): t S} be a Lipschitzian semigroup on C with lim inf |||T(t)||| < Np, where Np is n→ t s the normal structure coefficient of X. Suppose also there exists a nonempty bounded closed convex subset E of C with the following properties: (P1)x: E implies ωω(χ) C E; (P2)T is asymptotically regular on E. The authors prove that there exists a z E such that T(s)z = z for all s S. Fruther, under the similar condition, the existence of fixed points of Lipschitzian semigroups in a uniformly convex Banach space is discussed. 展开更多
关键词 Fixed points Lipschitzian semigroups Asymptotic regularity Normal structure coefficient Asymptotic center
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Canonical Metrics on Generalized Cartan-Hartogs Domains
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作者 Yihong HAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第3期357-366,共10页
Abstract In this paper, the author considers a class of bounded pseudoconvex domains, i.e., the generalized Cartan-Hartogs domains Ω(μ, m). The first result is that the natural Kahler metric gΩ(μ,m) of Ω(μ... Abstract In this paper, the author considers a class of bounded pseudoconvex domains, i.e., the generalized Cartan-Hartogs domains Ω(μ, m). The first result is that the natural Kahler metric gΩ(μ,m) of Ω(μ, m) is extremal if and only if its scalar curvature is a constant. The second result is that the Bergman metric, the Kahler-Einstein metric, the Caratheodary metric, and the Koboyashi metric are equivalent for Ω(μ, m). 展开更多
关键词 Canonical metric Extremal metric Comparison theorem GeneralizedCartan-Hartogs domains
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COHOMOLOGY VANISHING IN HILBERT SPACES
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作者 J.KAJIWARA LIXIAODONG K.H.SHON 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2004年第1期87-96,共10页
The authors give two cohomology vanishing theorems for domains, which are not pseudoconvex, and characterize the holomorphy of domains with smooth boundaries in separable Hilbert spaces through cohomology vanishing.
关键词 Infinite dimension Cohomology vanishing PSEUDOCONVEXITY
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A COUNTER-EXAMPLE CONCERNING THE ANALYTIC RADON-NIKODYM PROPERTY
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作者 BU SHANGQUAN (Department of Applied Mathematics, Qinghua University Beijing 100084, China.Project supported by the National Natural Science Foundation of China.) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第1期15-22,共8页
It is shown that there exists a J-convex subset C of a complex Hilbert space X, such that the J-convex hull of the set of all Jensen boundary points of C is different from C..
关键词 Analytic Radon-Nikodym property J-convex subset Jensen measures Jensen boundary point Banach spaces.
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The role of an integration identity in the analysis of the Cauchy-Leray transform
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作者 LANZANI Loredana STEIN Elias M. 《Science China Mathematics》 SCIE CSCD 2017年第11期1923-1936,共14页
The purpose of this paper is to complement the results by Lanzani and Stein(2017) by showing the dense definability of the Cauchy-Leray transform for the domains that give the counter-examples of Lanzani and Stein(201... The purpose of this paper is to complement the results by Lanzani and Stein(2017) by showing the dense definability of the Cauchy-Leray transform for the domains that give the counter-examples of Lanzani and Stein(2017), where L^p-boundedness is shown to fail when either the "near" C^2 boundary regularity, or the strong C-linear convexity assumption is dropped. 展开更多
关键词 Hardy space Cauchy integral Cauchy-Szego projection Lebesgue space pseudoconvex domain minimal smoothness Leray-Levi measure
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A CLOSEDNESS CRITERION FOR THEDIFFERENCE OF TWO CLOSED CONVEXSETS IN GENERAL BANACH SPACES
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作者 ANNEBEAULIEU ZHOUFENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1999年第3期337-340,共4页
The authors give some sufficient conditions for the difference of two closed convex sets to be closed in general Banach spaces, not necessarily reflexive.
关键词 Asymptotic cone Conjugate convex function Closedness Infimal Convolution
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Shock control bump optimization for a low sweep supercritical wing 被引量:4
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作者 DENG Feng QIN Ning +2 位作者 LIU XueQiang YU XiongQing ZHAO Ning 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第10期2385-2390,共6页
Shock control bumps are a promising technique in reducing wave drag of civil transport aircraft flying at transonic speeds.This paper investigates the optimization of 3D shock control bumps on a supercritical wing wit... Shock control bumps are a promising technique in reducing wave drag of civil transport aircraft flying at transonic speeds.This paper investigates the optimization of 3D shock control bumps on a supercritical wing with a sweep angle of 16°at the1/4 chord.A similar supercritical wing with a higher sweep angle of 24.5°at the 1/4 chord has been adopted as a baseline for the study.Numerical results show that the drag coefficient of the low sweep wing with the optimized 3D shock control bumps is reduced below that for the high sweep wing,indicating shock control bumps can be used as an effective means to reduce the wave drag caused by reducing the wing sweep angle.From the point of view of the wing structure design,lower sweep angle will also bring the benefits of weight reduction,resulting in further fuel reduction. 展开更多
关键词 supercritical wing low sweep angle shock control bump aerodynamic shape optimization computational fluiddynamics
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ON A BOUNDARY VALUE PROBLEM FOR A STURM-LIOUVILLE TYPE DIFFERENTIAL INCLUSION
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作者 Aurelian CERNEA 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第2期390-394,共5页
This paper proves a Filippov type existence theorem for solutions of a boundary valueproblem for a Sturm-Liouville type differential inclusion defined by a nonconvex set-valued map.Themethod consists in application of... This paper proves a Filippov type existence theorem for solutions of a boundary valueproblem for a Sturm-Liouville type differential inclusion defined by a nonconvex set-valued map.Themethod consists in application of the contraction principle in the space of selections of the set-valuedmap instead of the space of solutions. 展开更多
关键词 Boundary value problem contractive set-valued map fixed point.
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