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CYCLE CONTR0L FUNCTIONS AND THE NUMBER 0F LIMIT CYCLES
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作者 朱德明 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1991年第2期108-113,共6页
The cycle coatrol function is defined and used to estimate tbe number of limit cycles for someplanar autonomous systems. Some sufficient conditions for the existence of no or at most one limitcycles are given.
关键词 CYCLE CONTR0L functionS AND THE number 0F limit CYCLES
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Sequences and Limits
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作者 Wolfgang Mueckenheim 《Advances in Pure Mathematics》 2015年第2期59-61,共3页
It is widely held that irrational numbers can be represented by infinite digit-sequences. We will show that this is not possible. A digit sequence is only an abbreviated notation for an infinite sequence of rational p... It is widely held that irrational numbers can be represented by infinite digit-sequences. We will show that this is not possible. A digit sequence is only an abbreviated notation for an infinite sequence of rational partial sums. As limits of sequences, irrational numbers are incommensurable with any grid of decimal fractions. 展开更多
关键词 Series sequenceS limits DEFINABILITY of REAL numberS SET THEORY
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A Note on the Almost Sure Central Limit Theorem in the Joint Version for the Maxima and Partial Sums of Certain Stationary Gaussian Sequences
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作者 Yuanfang Wang Qunying Wu 《Applied Mathematics》 2014年第10期1598-1608,共11页
Considering a sequence of standardized stationary Gaussian random variables, a universal result in the almost sure central limit theorem for maxima and partial sum is established. Our result generalizes and improves t... Considering a sequence of standardized stationary Gaussian random variables, a universal result in the almost sure central limit theorem for maxima and partial sum is established. Our result generalizes and improves that on the almost sure central limit theory previously obtained by Marcin Dudzinski [1]. Our result reaches the optimal form. 展开更多
关键词 ALMOST Sure Central limit Theorem STATIONARY GAUSSIAN sequence Slowly Varying functions at INFINITY
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Pringsheim Convergence and the Dirichlet Function
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作者 Thomas Beatty Bradley Hansen 《Advances in Pure Mathematics》 2016年第6期441-445,共5页
Double sequences have some unexpected properties which derive from the possibility of commuting limit operations. For example, may be defined so that the iterated limits and  exist and are equal for all x, and ye... Double sequences have some unexpected properties which derive from the possibility of commuting limit operations. For example, may be defined so that the iterated limits and  exist and are equal for all x, and yet the Pringsheim limit does not exist. The sequence is a classic example used to show that the iterated limit of a double sequence of continuous functions may exist, but result in an everywhere discontinuous limit. We explore whether the limit of this sequence in the Pringsheim sense equals the iterated result and derive an interesting property of cosines as a byproduct. 展开更多
关键词 CONVERGENCE Pointwise limit Double sequence Pringsheim Dirichlet function Baire Category Theorem COSINE
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Generalized Harmonic Numbers Hn,k,r (α,β) with Combinatorial Sequences 被引量:1
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作者 Rui Wang   Wuyungaowa 《Journal of Applied Mathematics and Physics》 2022年第5期1602-1618,共17页
In this paper, we observe the generalized Harmonic numbers H<sub>n,k,r</sub> (α,β). Using generating function, we investigate some new identities involving generalized Harmonic numbers H<sub>n,k,r&... In this paper, we observe the generalized Harmonic numbers H<sub>n,k,r</sub> (α,β). Using generating function, we investigate some new identities involving generalized Harmonic numbers H<sub>n,k,r</sub> (α,β) with Changhee sequences, Daehee sequences, Degenerate Changhee-Genoocchi sequences, Two kinds of degenerate Stirling numbers. Using Riordan arrays, we explore interesting relations between these polynomials, Apostol Bernoulli sequences, Apostol Euler sequences, Apostol Genoocchi sequences. 展开更多
关键词 Generating function Riordan Arrays Generalized Harmonic numbers Changhee sequences Daehee sequences Apostol Bernoulli sequences Degenerate Changhee-Genoocchi sequences
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SOME CLASSES OF DIFFERENCE SEQUENCES OF FUZZY NUMBERS DEFINED BY A SEQUENCE OF MODULI
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作者 Ayhan Esi Mehmet Aikgz 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期229-236,共8页
In this article, we introduce and examine some properties of new difference sequence spaces of fuzzy numbers defined using a sequence of modulus functions.
关键词 Fuzzy numbers paranorm difference sequences modulus function
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A STRONG LIMIT THEOREM FOR GENERALIZED CANTOR-LIKE RANDOM SEQUENCES
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作者 刘文 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1996年第3期328-331,共4页
Let {qn, } be a sequence of positive integers, and In={0,1,..,qn}. The sequence of random variables {Xn, n0} is called a Cantor-like random sequence if for every n,Xn takes on values in In, and p(X0=x0,…Xn=xn)>0,T... Let {qn, } be a sequence of positive integers, and In={0,1,..,qn}. The sequence of random variables {Xn, n0} is called a Cantor-like random sequence if for every n,Xn takes on values in In, and p(X0=x0,…Xn=xn)>0,The purpose of this paper is to give a strong limit theorem for these sequences. 展开更多
关键词 Strong limit theorem strong law of large numbers a generalized Cantor-like random sequence
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与调和数有关的一类极限
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作者 雷冬霞 邱小霞 黄永忠 《大学数学》 2024年第5期43-47,共5页
利用Abel分部求和公式和Newton二项式定理对极限■给出计算式子,其中H_(n)(p)=■p,m,n为非负整数,p,q均为正整数,且p>1.进而给出n=0或m=0时以及m=n=1时的几个具体算例.
关键词 调和数 极限 Abel分部求和公式 ZETA函数
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基于指数函数的川滇地区余震序列衰减规律研究
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作者 徐世达 段俊康 +3 位作者 何本国 刘佳奇 鲍泽铭 陈天晓 《地震工程学报》 CSCD 北大核心 2024年第1期207-213,共7页
较大的余震可能造成额外损失并有二次触发建筑物受灾的风险。为研究余震序列衰减规律,文章尝试采用指数衰减模型拟合分析5个不同地区余震序列,并借助修正赤池信息准则、贝叶斯信息准则与调整后R^(2),分析其与传统余震衰减模型的性能。... 较大的余震可能造成额外损失并有二次触发建筑物受灾的风险。为研究余震序列衰减规律,文章尝试采用指数衰减模型拟合分析5个不同地区余震序列,并借助修正赤池信息准则、贝叶斯信息准则与调整后R^(2),分析其与传统余震衰减模型的性能。结果表明,指数模型描述余震序列衰减规律的能力与修正的大森余震模型、修正的拉伸指数模型接近。尤其对于四川长宁M_(S)6.0余震序列和云南彝良M_(S)5.7余震序列,指数模型表现优于其他两种模型。指数模型参数具有明确的物理意义:参数A与r之和能够准确代表强震后的实际初始余震数,5个余震序列初始余震数偏差均小于1.70%;参数k可作为反映余震序列衰减快慢的特征值,k值越大则余震序列衰减越慢,其值与主震震级呈反比例关系。 展开更多
关键词 余震序列 指数函数 初始余震数 衰减
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Semi-Continuity of Complex Fuzzy Functions
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作者 Magassy Ousmane 吴从炘 《Tsinghua Science and Technology》 SCIE EI CAS 2003年第1期65-70,共6页
This paper introduces the concept of semi-continuity of complex fuzzy functions, and discusses some of their elementary properties, such as the sum of two complex fuzzy functions of type I upper (lower) semi-continui... This paper introduces the concept of semi-continuity of complex fuzzy functions, and discusses some of their elementary properties, such as the sum of two complex fuzzy functions of type I upper (lower) semi-continuity is type I upper (lower) semi-continuous, and the opposite of complex fuzzy functions of type I upper (lower) semi-continuity is type I lower (upper) semi-continuous. Based on some assumptions on two complex fuzzy functions of type I upper (lower) semi-continuity, it is shown that their product is type I upper (lower) semi-continuous. The paper also investigates the convergence of complex fuzzy functions. In particular, sign theorem, boundedness theorem, and Cauchy's criterion for convergence are kept. In this paper the metrics introduced by Zhang Guangquan was used. This paper gives a contribution to the study of complex fuzzy functions, and extends the corresponding work of Zhang Guangquan. 展开更多
关键词 fuzzy number fuzzy complex number fuzzy distance fuzzy limit complex fuzzy semi-continuous function
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The Incompressible Limits of Compressible Navier-Stokes Equations in the Whole Space with General Initial Data
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作者 Ling HSIAO Qiangchang JU Fucai LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第1期17-26,共10页
It is showed that, as the Mach number goes to zero, the weak solution of the compressible Navier-Stokes equations in the whole space with general initial data converges to the strong solution of the incompressible Nav... It is showed that, as the Mach number goes to zero, the weak solution of the compressible Navier-Stokes equations in the whole space with general initial data converges to the strong solution of the incompressible Navier-Stokes equations as long as the later exists. The proof of the result relies on the new modulated energy functional and the Strichartz's estimate of linear wave equation. 展开更多
关键词 Compressible Navier-Stokes equations Incompressible Navier-Stokes equations Low Mach number limit Modulated energy functional Strichartz's estimate
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The Distribution of Prime Numbers and Finding the Factor of Composite Numbers without Searching
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作者 Dagnachew Jenber 《Advances in Pure Mathematics》 2015年第6期338-352,共15页
In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last o... In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last one to produce another three two-variable linear sequence functions. With the help of these three two-variable sequence functions, the last one, one-variable sequence function, is able to set apart all prime numbers from composite numbers. The formula shows that there are infinitely many prime numbers by applying limit to infinity. The three two-variable sequence functions help us to find the factor of all composite numbers. 展开更多
关键词 The nth sequence of an ARITHMETIC sequence number of Elements of the Set sequence functionS
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Gnedenko-Raikov’s Theorem Fails for Exchangeable Sequences
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作者 George Stoica Deli Li 《Applied Mathematics》 2012年第12期2019-2021,共3页
We study the connection between the central limit theorem and law of large numbers for exchangeable sequences, and provide a counterexample to the Gnedenko-Raikov theorem for such sequences.
关键词 Exchangeable sequenceS Central limit THEOREM WEAK LAW of Large numberS
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There Are Infinitely Many Mersnne Composite Numbers with Prime Exponents
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作者 Fengsui Liu 《Advances in Pure Mathematics》 2018年第7期687-698,共12页
By extending both arithmetical operations into finite sets of natural numbers, from the entire set of natural numbers successively deleting some residue classes modulo a prime, we invented a recursive sieve method or ... By extending both arithmetical operations into finite sets of natural numbers, from the entire set of natural numbers successively deleting some residue classes modulo a prime, we invented a recursive sieve method or algorithm on natural numbers and their sets. The algorithm mechanically yields a sequence of sets, which converges to the set of all primes p such that 2p + 1 divides the Mersenne number Mp. The cardinal sequence corresponding to the sequence of sets is strictly increasing. So that we have captured enough usable structures, without any estimation, the existing theories of those structures allow us to prove an exact result: there are infinitely many Mersenne composite numbers with prime exponents Mp. 展开更多
关键词 Mersenne Composite numberS Sophie German PRIMES RECURSIVE Algorithm Order Topology limit of sequence of Sets
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(<i>f</i>, <i>p</i>)-Asymptotically Lacunary Equivalent Sequences with Respect to the Ideal <i>I</i>
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作者 Tunay Bilgin 《Journal of Applied Mathematics and Physics》 2015年第9期1207-1217,共11页
In this study, we define (f, p)-Asymptotically Lacunary Equivalent Sequences with respect to the ideal I using a non-trivial ideal , a lacunary sequence , a strictly positive sequence , and a modulus function f, and o... In this study, we define (f, p)-Asymptotically Lacunary Equivalent Sequences with respect to the ideal I using a non-trivial ideal , a lacunary sequence , a strictly positive sequence , and a modulus function f, and obtain some revelent connections between these notions. 展开更多
关键词 ASYMPTOTICALLY EQUIVALENCE Ideal Convergence Lacunary sequence MODULUS function Statistically limit
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滚动轴承内圈局部故障渐变动力学建模与分析 被引量:1
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作者 尚志武 庞海玉 +1 位作者 高茂生 刘静宇 《机械强度》 CAS CSCD 北大核心 2023年第4期778-784,共7页
当滚动轴承内圈出现局部故障时会产生复杂的振动响应,从滚动轴承内圈实际故障形貌的渐变性和非规则性的客观实际出发,引入位移激励函数定性分析滚动体通过故障区域时球心位置的渐变规律,采用随机数列表征故障底部形貌非规则性的特点,综... 当滚动轴承内圈出现局部故障时会产生复杂的振动响应,从滚动轴承内圈实际故障形貌的渐变性和非规则性的客观实际出发,引入位移激励函数定性分析滚动体通过故障区域时球心位置的渐变规律,采用随机数列表征故障底部形貌非规则性的特点,综合考虑轴承的径向载荷和滚动体通过故障区域时的打滑率等因素,建立了一种内圈局部故障渐变的轴承动力学模型。通过对比分析不同转频条件下实验和仿真数据的故障特征频率值,验证了局部故障渐变动力学模型的准确性。 展开更多
关键词 故障渐变 位移激励函数 随机数列 滑动率 故障特征频率
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Extensions of the Constructivist Real Number System
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作者 E. E. Escultura 《Advances in Pure Mathematics》 2018年第8期720-754,共35页
The paper reviews the most consequential defects and rectification of traditional mathematics and its foundations. While this work is only the tip of the iceberg, so to speak, it gives us a totally different picture o... The paper reviews the most consequential defects and rectification of traditional mathematics and its foundations. While this work is only the tip of the iceberg, so to speak, it gives us a totally different picture of mathematics from what we have known for a long time. This journey started with two teasers posted in SciMath in 1997: 1) The equation 1 = 0.99… does not make sense. 2) The concept ?does not exist. The first statement sparked a debate that raged over a decade. Both statements generated a series of publications that continues to grow to this day. Among the new findings are: 3) There does not exist nondenumerable set. 4) There does not exist non-measurable set. 5) Cantor’s diagonal method is flawed. 6) The real numbers are discrete and countable. 7) Formal logic does not apply to mathematics. The unfinished debate between logicism, intuitionism-constructivism and formalism is resolved. The resolution is the constructivist foundations of mathematics with a summary of all the rectification undertaken in 2015, 2016 and in this paper. The extensions of the constructivist real number system include the complex vector plane and transcendental functions. Two important results in the 2015 are noted: The solution and resolution of Hilbert’s 23 problems that includes the resolution of Fermat’s last theorem and proof Goldbach’s conjecture. 展开更多
关键词 CONSTRUCTIVISM DARK number Fermat’s CONJECTURE g-Norm g-sequence g-limit Goldbach’s CONJECTURE TRUNCATION Vector Operators j and
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一致收敛二元函数列及函数项级数的含参量积分性质
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作者 费时龙 任雅柔 《吉林化工学院学报》 CAS 2023年第1期95-98,共4页
目的是利用二元函数列的性质研究其极限函数及二元函数项级数的含参量积分的相关性质。通过二元函数列的含参量积分存在性、连续性、可微性及可积性研究了一致收敛的极限函数及函数项级数和函数对应的含参量积分的存在性、连续性、可微... 目的是利用二元函数列的性质研究其极限函数及二元函数项级数的含参量积分的相关性质。通过二元函数列的含参量积分存在性、连续性、可微性及可积性研究了一致收敛的极限函数及函数项级数和函数对应的含参量积分的存在性、连续性、可微性与可积性。获得了一致收敛意义下极限函数对应的含参量积分与极限交换次序、求导交换次序及累次积分交换次序的条件,得到了一致收敛意义下含参量积分与无穷求和交换次序,含参量积分的求导与无穷求和交换次序的条件。 展开更多
关键词 一致收敛 含参量积分 二元函数列 极限函数 函数项级数 和函数
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基于混合策略的改进哈里斯鹰优化算法 被引量:4
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作者 张海林 陈泯融 《计算机系统应用》 2023年第1期166-178,共13页
针对原始哈里斯鹰优化算法(HHO)存在的收敛精度低、收敛速度慢、易陷入局部最优等不足,提出了一种基于混合策略的改进哈里斯鹰优化算法(HSHHO).首先,在种群初始化阶段引入Sobol序列,生成均匀分布的种群,提高种群的多样性,有利于提高算... 针对原始哈里斯鹰优化算法(HHO)存在的收敛精度低、收敛速度慢、易陷入局部最优等不足,提出了一种基于混合策略的改进哈里斯鹰优化算法(HSHHO).首先,在种群初始化阶段引入Sobol序列,生成均匀分布的种群,提高种群的多样性,有利于提高算法的收敛速度;其次,引入limit阈值,令算法在一定迭代次数没有获得更优值后执行全局探索操作,提高算法跳出局部最优解的能力,改善HHO在迭代后期只执行开发阶段而易陷入局部最优的缺陷;最后,提出一种动态的反向学习机制,提高算法的收敛精度以及跳出局部最优的能力.在9个基准函数和6个CEC2017函数上进行测试,与其他多种优化算法、HHO变体作对比,验证所提出策略的有效性,并进行Wilcoxon符号秩检验、Friedman检验和Quade检验等非参数检验.实验结果表明, HSHHO在收敛速度、寻优精度和统计测试方面具有较为优秀的性能.最后,还应用到焊接梁设计优化问题,结果表明改进的算法对于带约束的实际工程优化问题也具有更好的效果. 展开更多
关键词 函数优化 哈里斯鹰优化算法 Sobol序列 limit阈值 动态反向学习
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蒙特卡罗方法的应用及算例 被引量:25
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作者 何凤霞 张翠莲 《华北电力大学学报(自然科学版)》 CAS 北大核心 2005年第3期110-112,共3页
利用概率极限定理思想,设计二重积分的蒙特卡罗算法,通过方差分析,选择适当的随机数,得到了理论意义下的方差最小算法,用实际算例验证了该方法的优良性。
关键词 蒙特卡罗方法 算例 应用 蒙特卡罗算法 极限定理 二重积分 方差分析 理论意义 随机数 优良性 概率
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