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ECHOS OF THE STEINER-LEHMUS EQUAL BISECTORS THEOREM
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作者 Christoph BÖRGERS Eric L.GRINBERG +1 位作者 Mehmet ORHON Junhao SHEN 《Acta Mathematica Scientia》 2025年第1期257-263,共7页
The Steiner-Lehmus equal bisectors theorem originated in the mid 19th century.Despite its age,it would have been accessible to Euclid and his contemporaries.The theorem remains evergreen,with new proofs continuing to ... The Steiner-Lehmus equal bisectors theorem originated in the mid 19th century.Despite its age,it would have been accessible to Euclid and his contemporaries.The theorem remains evergreen,with new proofs continuing to appear steadily.The theorem has fostered discussion about the nature of proof itself,direct and indirect.Here we continue the momentum by providing a trigonometric proof,relatively short,based on an analytic estimate that leverages algebraic trigonometric identities.Many proofs of the theorem exist in the literature.Some of these contain key ideas that already appeared in C.L.Lehmus’1850 proofs,not always with citation.In the aim of increasing awareness of and making more accessible Lehmus’proofs,we provide an annotated translation.We conclude with remarks on different proofs and relations among them. 展开更多
关键词 Steiner-Lehmus theorem equal bisectors
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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SOME LIOUVILLE-TYPE THEOREMS FOR THE STATIONARY 3D MAGNETO-MICROPOLAR FLUIDS
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作者 Jae-Myoung KIM Seungchan KO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2296-2306,共11页
In this paper,we prove some Liouville-type theorems for the stationary magnetomicropolar fluids under suitable conditions in three space dimensions.We first prove that the solutions are trivial under the assumption of... In this paper,we prove some Liouville-type theorems for the stationary magnetomicropolar fluids under suitable conditions in three space dimensions.We first prove that the solutions are trivial under the assumption of certain growth conditions for the mean oscillations of the potentials.And then we show similar results assuming that the solutions are contained in L^(p)(R^(3))with p∈[2,9/2).Finally,we show the same result for lower values of p∈[1,9/4)with the further assumption that the solutions vanish at infinity. 展开更多
关键词 stationary magneto-micropolar equations Liouville-type theorem
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井下专用乳化基质黏弹性分析
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作者 孙伟博 杨健 +2 位作者 翟小鹏 简国祚 王燕 《工程爆破》 北大核心 2025年第1期95-101,共7页
井下上向中深孔爆破用乳化炸药黏度高,其流变特性大小对井下乳化炸药的输送至关重要,而不同的输送效率对应了不同的剪切速率。对温度分别为25℃和50℃的乳化基质进行了大振幅振荡剪切等流变实验,实验结果表明:振荡频率为0.1 Hz和1 Hz时... 井下上向中深孔爆破用乳化炸药黏度高,其流变特性大小对井下乳化炸药的输送至关重要,而不同的输送效率对应了不同的剪切速率。对温度分别为25℃和50℃的乳化基质进行了大振幅振荡剪切等流变实验,实验结果表明:振荡频率为0.1 Hz和1 Hz时,乳化基质储能模量与耗能模量相对大小转换的临界剪切应变值分别为10%和40%。对测量结果进行傅里叶变换,结合切比雪夫理论分析发现,振荡频率0.1 Hz和1 Hz下,乳化基质表现出应变变硬特性的临界剪切应变值分别为10%和25%,剪切增稠比率由非稳态过渡到剪切增稠的剪切应变值分别为1%和5%。研究表明:乳化基质在高剪切应变值下的黏弹性以非线性为主,根据25℃和50℃下应变硬化比率和剪切增稠比率的过渡值相同可以看出乳化基质的黏弹性对温度不敏感,主要与振荡频率有关。随着剪切强度增强,乳化基质表现出应变变硬和剪切增稠的特性。 展开更多
关键词 乳化基质 非线性黏弹性 大振幅振荡剪切 傅里叶变换 切比雪夫定理
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具有时滞和非局部边界条件的分数阶Langevin方程解的存在性与稳定性
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作者 周文学 张敏 黎文博 《应用数学》 北大核心 2025年第1期1-13,共13页
本文研究一类具有时滞和非局部边界条件的分数阶Langevin方程解的存在性与稳定性.首先使用Burton-Kirk不动点定理和压缩映射原理证明解的存在性与唯一性,其次讨论了边值问题的Hyers-Ulam稳定性,最后举例说明所得结果的有效性.
关键词 分数阶Langevin方程 时滞 不动点定理 HYERS-ULAM稳定性
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含参数的 p -Laplacian分数阶微分方程多重正解的存在性
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作者 吴克晴 徐紫钰 蔡序军 《兰州理工大学学报》 北大核心 2025年第1期166-172,共7页
考虑了一类具有p-Laplacian算子同时非线性项含积分项的Riemann-Liouville型非线性分数阶微分方程,分析其在包含参数及分数阶积分条件的边界条件下的多重正解的存在性.利用格林函数将问题转化为积分方程,并在Banach空间中运用Leggett-Wi... 考虑了一类具有p-Laplacian算子同时非线性项含积分项的Riemann-Liouville型非线性分数阶微分方程,分析其在包含参数及分数阶积分条件的边界条件下的多重正解的存在性.利用格林函数将问题转化为积分方程,并在Banach空间中运用Leggett-Williams不动点定理和广义Avery-Henderson不动点定理获得主要结果,通过一个实例说明所得结果的适用性. 展开更多
关键词 P-LAPLACIAN算子 参数 多重正解 不动点定理
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基于系统分解与集成的体系博弈预期评估
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作者 王正明 刘吉英 《国防科技》 2025年第1期1-9,共9页
基于系统分解与集成技术,从婚恋模型出发,研究体系博弈,解读战略防御、相持、反攻,解读军事行动的先后顺序,得到直观、符合指挥员思维习惯与数学逻辑的结论。研究表明,许多复杂系统可以表示为简单的一维问题,用一元正态分布或成败型试... 基于系统分解与集成技术,从婚恋模型出发,研究体系博弈,解读战略防御、相持、反攻,解读军事行动的先后顺序,得到直观、符合指挥员思维习惯与数学逻辑的结论。研究表明,许多复杂系统可以表示为简单的一维问题,用一元正态分布或成败型试验模型分析解读。该方法可以用于解读部分多智能体博弈的结果。研究成果为分析评估国家安全、地区冲突等复杂系统的预期,提供了一种理论依据、建模方法和数据分析技术。 展开更多
关键词 系统分解 系统集成 体系博弈 科尔莫戈罗夫-阿诺德表示定理 正态分布
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THEOREMS OF INTERVAL FUZZY SET AND ITS OPERATION RULES 被引量:3
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作者 吴顺祥 曹达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期136-144,共9页
Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuz... Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuzzy set are studied firstly, and then the cut set of interval fuzzy set is proposed. Moreover, the decomposition theo- rem, the representation theorem and the extension theorem of interval fuzzy set are presented. Finally, examples are given to demonstrate that the classical fuzzy set is a special case of interval fuzzy set and interval fuzzy set is an effective expansion of the classical fuzzy set. 展开更多
关键词 interval fuzzy set decomposition theorem representation theorem extension theorem
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The Growth Theorem for Convex Maps on the Banach Space 被引量:7
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作者 张文俊 董道珍 汪远征 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期84-87,共4页
In this paper,the growth theorem for convex maps on the Banach space is given, this is: ‖f(x)‖≤‖x‖/(1-‖x‖),x∈B the estimate is best possible for Hilbert space.
关键词 holomorphic maps convex maps Schwartz lemma Growth theorem
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Several Fundamental Theorems and Conservative Integrals in Quasicrystal Elasticity Theory 被引量:1
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作者 李显方 孙应飞 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期226-232,共7页
Aim To extend several fundamental theorems of conventional elasticity theory to quasicrystalelasticity theory. Methods The basic governing equations of quasicrystal elasticity theory and Gauss's theorem were appli... Aim To extend several fundamental theorems of conventional elasticity theory to quasicrystalelasticity theory. Methods The basic governing equations of quasicrystal elasticity theory and Gauss's theorem were applied in the derivation. Results and Conclusion The principle of virtual work, Betti's reciprocal theorem and the uniqueness theorem of quasicrystal elasticity theory are proud, and some conservative integrals in quasicrystal elasticty theory are obtained. 展开更多
关键词 quasicrystal elasticity theory conservative integral the principle ofvirtual work Betti's reciprocal theorem the uniqueness theorem
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On Some Fundamental Theorems in Stability Theory 被引量:26
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作者 徐道义 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期61-67,共7页
This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on ce... This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7]. 展开更多
关键词 STABILITY Lyapunov fundamental theorem nonautonomous differential equations
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The Growth Theorem for Almost Starlike Mappings of Order α on Bounded Starlike Circular Domains 被引量:3
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作者 冯淑霞 卢克平 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期50-56,共7页
In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it.... In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it. This type of domain on which we discuss is rather general,in the sense that the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. 展开更多
关键词 almost starlike mapping of order α growth theorem starlike circular domains
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A Generalization of Caristi Fixed Point Theorem 被引量:5
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作者 孙经先 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期72-75,共4页
Let X be a metric space with an ordering structure,A: X→X is a operator and x≤Ax for any x∈X. In this paper we prove a new fixed point theorem, which generalizes famous caristi fixed point theorem.
关键词 metric space partially ordred set fixed point theorem
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A Simple Proof for the Bondy Theorem on Pancyclic Graphs
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作者 赵克文 韩烽 李大超 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期14-15,共2页
A new short proof is given for the Bondy Theorem on pancyclic graphs.
关键词 Bondy theorem PANCYCLIC cycles
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Radon-Nikodym Theorem of Signed Additive Fuzzy Measure
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作者 纪爱兵 陈学周 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第4期25-29,共5页
This is subsequent of , by using the theory of additive fuzzy measure and signed additive fuzzy measure , we prove the Radon_Nikodym Theorem and Lebesgue decomposition Theorem of signed additive fuzzy measure.
关键词 signed additive fuzzy measure Radon_Nikodym theorem Lebesgue decomposition theorem
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基于贝叶斯理论的钢混组合高层建筑多灾易损性估算-地震和风
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作者 郑晓伟 程杰 +1 位作者 张令心 谢贤鑫 《振动与冲击》 北大核心 2025年第2期160-166,共7页
该研究提出了一种基于贝叶斯理论的高层建筑多灾易损性估算方法,用于评估地震和风荷载同时作用下建筑结构的条件破坏概率,并量化了多重不确定性的影响。该研究对高层建筑多灾易损性研究领域的主要贡献在于:(1)通过贝叶斯理论,建立结构... 该研究提出了一种基于贝叶斯理论的高层建筑多灾易损性估算方法,用于评估地震和风荷载同时作用下建筑结构的条件破坏概率,并量化了多重不确定性的影响。该研究对高层建筑多灾易损性研究领域的主要贡献在于:(1)通过贝叶斯理论,建立结构多灾需求模型中未知参数的后验概率分布;(2)提出计算结构多灾易损性边界的方法,并基于全概率理论将随机变量的概率密度函数积分到易损性中,以此量化模型的认识不确定性。最后,以一个具有代表性的42层钢-混组合高层建筑为研究对象,对所提出的多灾易损性估算方法进行展示。研究结果表明,模型参数的认知不确定性以及荷载加载方向对结构破坏概率存在显著影响。所提出的基于贝叶斯理论的多灾易损性估算方法,有助于高层建筑的多灾害综合防控与防灾决策制定。 展开更多
关键词 多灾害 贝叶斯理论 不确定性 易损性 组合结构
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光学牵引力研究融入动量守恒定律教学的探讨
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作者 曹永印 周可雅 +2 位作者 任延宇 丁卫强 张宇 《大学物理》 2025年第1期42-44,48,共4页
学生在中学已经学习了动量守恒定律的相关内容.如何在大学物理授课中体现相关内容的高阶性、创新性和挑战度,如何让学生感受到更多的新鲜感和深层次认知,是授课教师需要深思的问题.本文尝试将光学牵引力研究融入动量守恒定律的教学中,... 学生在中学已经学习了动量守恒定律的相关内容.如何在大学物理授课中体现相关内容的高阶性、创新性和挑战度,如何让学生感受到更多的新鲜感和深层次认知,是授课教师需要深思的问题.本文尝试将光学牵引力研究融入动量守恒定律的教学中,通过产生光学牵引力的物理机制的探讨,展示如何将前沿科学研究引入到大学物理教学中,以提高授课内容的高阶性、创新性和挑战度,激发学生的学习兴趣和对基础知识的深入理解. 展开更多
关键词 动量守恒定律 动量定理 光学牵引力
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A Remark of M.Riesz Theorem
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作者 田长安 杨长森 程小强 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期53-58,共6页
Let u(z) be a real_valued harmonic function in the unit disk, we say u(z)∈h p(1【p【+∞), if the p _mean M p(r,u)=12π∫ 2π 0|u(re i θ )| p d θ 1/p is bounded. M.Riesz showed ... Let u(z) be a real_valued harmonic function in the unit disk, we say u(z)∈h p(1【p【+∞), if the p _mean M p(r,u)=12π∫ 2π 0|u(re i θ )| p d θ 1/p is bounded. M.Riesz showed that if u(z)∈h p(1【p【+∞), then there exists a constant A p, depending only on p such that M p(r,v)≤A pM p(r,u), where v(z) is the conjugate harmonic function of u(z).When v(0)=0 and 1【p≤2, W.K.Hayman showed that A p can be given by pp-1 1/p . First, this paper shows that the constant pp-1 1/p can be changed by a smaller constant pp-1 2/p -1 1/2 . Next, if 1【p≤2, then there exists a constant θ 0∈2-p2pπ,π2p such that M p p(r,v)≤ Im p sin pπ2+ tg pπ2pM p p(r,u) for any analytic function f(z)=u(z)+ i v(z) in the unit disk, whenever -θ 0【 arg f(z)【π2. 展开更多
关键词 conjugate harmonic function M. Riesz theorem
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The Growth Theorem for Strongly Starlike Mappings of Order α on Bounded Starlike Circular Domains
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作者 刘浩 李小申 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期28-33,共6页
The authors obtain the growth and covering theorems for strongly starlike mappings of order α on bounded starlike circular domains.This kind of domain discussed is rather general,since the domain must be starlike if ... The authors obtain the growth and covering theorems for strongly starlike mappings of order α on bounded starlike circular domains.This kind of domain discussed is rather general,since the domain must be starlike if exists a normalized biholomorphic starlike mapping on it. 展开更多
关键词 strongly starlike mappings of order α growth theorem startike circular domains
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一类非线性趋化方程的双线性最优控制
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作者 许万杰 张亮 《应用数学》 北大核心 2025年第1期143-155,共13页
本文研究一类非线性趋化方程的双线性最优控制.首先利用Leray-Schauder不动点定理证明抛物型方程组强解的存在唯一性,其次通过极小化序列讨论最优控制的存在性,最后通过控制状态算子L的Fréchet可微性建立了变分不等式并得出一阶必... 本文研究一类非线性趋化方程的双线性最优控制.首先利用Leray-Schauder不动点定理证明抛物型方程组强解的存在唯一性,其次通过极小化序列讨论最优控制的存在性,最后通过控制状态算子L的Fréchet可微性建立了变分不等式并得出一阶必要条件. 展开更多
关键词 Keller-Segel模型 最优控制 LERAY-SCHAUDER不动点定理 必要最优性条件
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