期刊文献+
共找到317篇文章
< 1 2 16 >
每页显示 20 50 100
Some Strong Limit Theorems for Even-odd Markov Chain Fields Indexed by Trees
1
作者 MA Li-na CHEN Shuang +1 位作者 LUO Yun-ling LI Nai-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第4期550-558,共9页
First,a class of strong limit theorems are proved by constructing two nonnegative martingales.Then they are applied to the study of all kinds of even-odd Markov chain fields and Markov chain fields defined in the pape... First,a class of strong limit theorems are proved by constructing two nonnegative martingales.Then they are applied to the study of all kinds of even-odd Markov chain fields and Markov chain fields defined in the paper.Finally,some strong limit theorems for the even-odd Markov chain fields and Markov chain fields are obtained. 展开更多
关键词 strong limit theorem even-odd Markov chain fields generalized Bethe tree
下载PDF
Likelihood Ratio and Strong Limit Theorems for the Discrete Random Variable
2
作者 Wenhan Li Wei Wang Zhiqiang Liu 《Open Journal of Discrete Mathematics》 2012年第4期169-172,共4页
This in virtue of the notion of likelihood ratio and the tool of moment generating function, the limit properties of the sequences of random discrete random variables are studied, and a class of strong deviation theor... This in virtue of the notion of likelihood ratio and the tool of moment generating function, the limit properties of the sequences of random discrete random variables are studied, and a class of strong deviation theorems which represented by inequalities between random variables and their expectation are obtained. As a result, we obtain some strong deviation theorems for Poisson distribution and binomial distribution. 展开更多
关键词 LIKELIHOOD Ratio strong limit THEOREM MOMENT GENERATING Function
下载PDF
Tree-Indexed Markov Chains in Random Environment and Some of Their Strong Limit Properties
3
作者 Zhiyan SHI Bei WANG +1 位作者 Weiguo YANG Zhongzhi WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2022年第4期621-642,共22页
In this paper,the authors first introduce the tree-indexed Markov chains in random environment,which takes values on a general state space.Then,they prove the existence of this stochastic process,and develop a class o... In this paper,the authors first introduce the tree-indexed Markov chains in random environment,which takes values on a general state space.Then,they prove the existence of this stochastic process,and develop a class of its equivalent forms.Based on this property,some strong limit theorems including conditional entropy density are studied for the tree-indexed Markov chains in random environment. 展开更多
关键词 Random environment Tree-indexed Markov chains strong limit theorem Conditional entropy density
原文传递
Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. I: Deduction and geometric illustration
4
作者 宋光世 《Journal of Chongqing University》 CAS 2003年第2期104-108,共5页
Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differen... Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differentials of unitary indeterminate forms. The fruit of this work is going to be reported in three parts. The first part presents the standard analysis on this subject which supplements, systematizes and advances L. Hospital抯 principles on differential calculus by applying special ,general, and limit guaranteeing theories together with K(t) and XhK0 theories. The combination of theoretical analysis and geometric signification makes the derivation intuitional, visual and easy to perceive. 展开更多
关键词 strong limit weak limit strong differential weak differential indeterminate form multi-variable special form general form
下载PDF
A STRONG LIMIT THEOREM FOR GENERALIZED CANTOR-LIKE RANDOM SEQUENCES
5
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
原文传递
STRONG LIMIT POINT FOR LINEAR HAMILTONIAN DIFFERENCE SYSTEM 被引量:1
6
作者 Sun Shurong Han Zhenlai Chen Shaozhu 《Annals of Differential Equations》 2005年第3期407-411,共5页
The definition of strong limit-point for singular Hamiltonian difference expressions with complex coefficients are given, and some strong limit-point criteria are established.
关键词 minimal operator maximal operator limit point strong limitpoint
原文传递
Stripe-type charge ordering developed at the strong limit of nematicity in FeSe film
7
作者 Li Wei (李渭) Chen Xi (陈曦) +1 位作者 Xue Qikun (薛其坤) Shen Zhixun (沈志勋) 《Science Foundation in China》 CAS 2017年第3期24-24,共1页
Subject Code:A04With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Profs.Li Wei(李渭),Chen Xi(陈曦)and Xue Qikun(薛其坤)from Tsinghua University an... Subject Code:A04With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Profs.Li Wei(李渭),Chen Xi(陈曦)and Xue Qikun(薛其坤)from Tsinghua University and Prof.Shen Zhixun(沈志勋)from Stanford University,demonstrates stripes developed 展开更多
关键词 Stripe-type charge ordering developed at the strong limit of nematicity in FeSe film
原文传递
Supercritical superprocesses: Proper normalization and non-degenerate strong limit 被引量:1
8
作者 Yan-Xia Ren Renming Song Rui Zhang 《Science China Mathematics》 SCIE CSCD 2019年第8期1519-1552,共34页
Suppose that X ={Xt, t≥0;Pμ} is a supercritical superprocess in a locally compact separable metric space E. Let φ0 be a positive eigenfunction corresponding to the first eigenvalue λ0 of the generator of the mean ... Suppose that X ={Xt, t≥0;Pμ} is a supercritical superprocess in a locally compact separable metric space E. Let φ0 be a positive eigenfunction corresponding to the first eigenvalue λ0 of the generator of the mean semigroup of X. Then Mt := e-λ0t〈φ0,Xt〉 is a positive martingale. Let M∞ be the limit of Mt. It is known(see Liu et al.(2009)) that M∞ is non-degenerate if and only if the L log L condition is satisfied. In this paper we are mainly interested in the case when the L log L condition is not satisfied. We prove that, under some conditions, there exist a positive function γt on [0,∞) and a non-degenerate random variable W such that for any finite nonzero Borel measure μ on E,lim/t→∞γt〈φ0,Xt〉=W, a.s.-Pμ.We also give the almost sure limit of γt〈f, Xt〉for a class of general test functions f. 展开更多
关键词 SUPERPROCESSES Seneta-Heyde norming non-degenerate strong limit MARTINGALES
原文传递
ON NUMBER OF LIMIT CYCLES FOR THE QUADRATIC SYSTEMS WITH A WEAK FOCUS AND A STRONG FOCUS 被引量:1
9
作者 Zhang Pingguang Zhao ShenqiDept.ofMath.ZhejiangUniv.,Hangzhou310027. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第2期127-132,共6页
It is proved that the quadratic system with a weak focus and a strong focus has at most one limit cycle around the strong focus, and as the weak focus is a 2nd order(or 3rd order) weak focus the quadratic system ha... It is proved that the quadratic system with a weak focus and a strong focus has at most one limit cycle around the strong focus, and as the weak focus is a 2nd order(or 3rd order) weak focus the quadratic system has at most two(one) limit cycles which have (1,1) distribution ((0,1) distribution). 展开更多
关键词 Quadratic differential system number of limit cycle weak focus strong focus.
下载PDF
STRONG EMBEDDING OF PRODUCT-LIMIT ESTIMATOR OF BIVARIATE SURVIVAL DISTRIBUTION FUNCTION UNDER RANDOM CENSORSHIP
10
作者 王启华 《Acta Mathematica Scientia》 SCIE CSCD 1995年第S1期123-132,共10页
Let (X0,Y0), be i. i. d nonnegative random vectors with continuous survival distribution function be the product-limit estimator of S(s,t) suggested by Campbell and Foldes (1980). In this paper it is shown that under... Let (X0,Y0), be i. i. d nonnegative random vectors with continuous survival distribution function be the product-limit estimator of S(s,t) suggested by Campbell and Foldes (1980). In this paper it is shown that under some conditions a sequence of Gaussian processes Gn(s,t) can be constructed such that sup a. s.,for S,T which together satisfy a certain condition. 展开更多
关键词 strong Embedding Product-limit Estimator Survival Distribution
下载PDF
AN ANALOGUE OF KüNNETH THEOREM INSTRONG HOMOLOGY 被引量:1
11
作者 Dae- Woong Lee 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期32-40,共9页
After defining the strong tensor product of strong (sub)chain complenes, it is shown that an analogue of the Kunneth theorem holds in strong homology by proving that the kernel (cokernel) of connecting homomorphisms i... After defining the strong tensor product of strong (sub)chain complenes, it is shown that an analogue of the Kunneth theorem holds in strong homology by proving that the kernel (cokernel) of connecting homomorphisms is isomorphic to the direct sum of torsion (tensor) products of strong homology groups. An isomorphism between strong (r-stage) homology groups of inverse systems is also constructed. 展开更多
关键词 Derived limit strong (r-stage) homology strong tensor product Mittag-Leffler property
下载PDF
New Factor to Characterize Mechanism of “Strong Column-Weak Beam” of RC Frame Structures 被引量:1
12
作者 李心霞 公茂盛 +1 位作者 韩庆华 谢礼立 《Transactions of Tianjin University》 EI CAS 2015年第6期484-491,共8页
Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To ... Most reinforced concrete(RC)frame structures did not achieve the "strong column-weak beam" failure mode in recent big earthquakes, resulting in a large number of casualties and significant property loss. To deal with this serious problem, a new column-beam relative factor was proposed to characterize the relative yield situation of column ends and beam ends. By limiting the column-beam relative factor, RC frame structures could achieve the "strong column-weak beam" failure mode under the excitation of strong ground motions. The limit values of column-beam relative factor were calculated, analyzed and verified by using structural simulation models for corner columns in the bottom story of structures, which are destroyed most seriously in earthquakes. The results show that the limit values should be analyzed under bi-directional ground motion and with different axial compression ratios of columns. The peak ground acceleration(PGA)of ground motions has no significant effect on the limit values, while the type of strong ground motions has a significant effect on the limit values. 展开更多
关键词 RC frame structure strong column-weak beam limit value of column-beam relative factor moment magnification factor at column end
下载PDF
STRONG REPRESENTATIONS OF THE SURVIVAL FUNCTION ESTIMATOR ON INCREASING SETS FOR TRUNCATED AND CENSORED DATA
13
作者 孙六全 郑忠国 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期251-260,共10页
In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. wh... In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. which are valid up to a given order statistic of the observations. A precise bound for the errors is obtained which only depends on the index of the last order statistic to be included. 展开更多
关键词 truncated and censored data cumulative hazard function product-limit estimator strong representations
下载PDF
Limit Theorems for a Storage Process with a Random Release Rule
14
作者 Lakhdar Meziani 《Applied Mathematics》 2012年第11期1607-1613,共7页
We consider a discrete time Storage Process Xn with a simple random walk input Sn and a random release rule given by a family {Ux, x ≥ 0} of random variables whose probability laws {Ux, x ≥ 0} form a convolution sem... We consider a discrete time Storage Process Xn with a simple random walk input Sn and a random release rule given by a family {Ux, x ≥ 0} of random variables whose probability laws {Ux, x ≥ 0} form a convolution semigroup of measures, that is, μx × μy = μx + y The process Xn obeys the equation: X0 = 0, U0 = 0, Xn = Sn - USn, n ≥ 1. Under mild assumptions, we prove that the processes and are simple random walks and derive a SLLN and a CLT for each of them. 展开更多
关键词 STORAGE PROCESS RANDOM WALK strong Law of Large NUMBERS Central limit THEOREM
下载PDF
非齐次树上非齐次马氏链转移矩阵的一个极限性质
15
作者 金少华 李慧云 +1 位作者 臧婷 贺雅萍 《高等数学研究》 2024年第1期22-24,46,共4页
通过引入样本散度的概念和构造辅助非负鞅,利用Doob鞅收敛定理给出了非齐次树上k重非齐次马氏链转移矩阵的一个极限性质.
关键词 非齐次树 马氏链 强极限定理 转移矩阵
下载PDF
电磁防护技术发展综述与展望
16
作者 毋召锋 徐延林 +1 位作者 刘培国 查淞 《强激光与粒子束》 CAS CSCD 北大核心 2024年第4期1-13,共13页
针对复杂电磁对抗环境中电子信息装备面临的强电磁环境威胁以及防护加固需求,对强电磁防护技术的发展现状进行了综述,并提出了强电磁系统级综合防护的发展展望。强电磁防护是为了保证电子信息装备在强电磁环境中免受损伤或损毁的技术手... 针对复杂电磁对抗环境中电子信息装备面临的强电磁环境威胁以及防护加固需求,对强电磁防护技术的发展现状进行了综述,并提出了强电磁系统级综合防护的发展展望。强电磁防护是为了保证电子信息装备在强电磁环境中免受损伤或损毁的技术手段,从电磁波的耦合途径分析了当前电磁防护的重点和难点,然后分别以限幅器技术、频率滤波技术、能量选择防护技术三个方面对前门防护技术的发展现状进行了分析总结,最后从新型屏蔽材料和防护器件两个方面对新型电磁防护技术进行了展望,并从前后门一体防护、场路一体防护、多域联合防护三个角度对系统级电磁防护进行了总结,为电子信息装备在复杂电磁环境下的电磁防护加固设计提供了支撑。 展开更多
关键词 电磁防护 强电磁环境 限幅器技术 能量选择技术 频域滤波技术
下载PDF
基于实验的碳酸盐岩气藏储量计算——以X气藏为例
17
作者 杨学峰 闫伟林 +1 位作者 周聪 殷树军 《天然气勘探与开发》 2024年第3期12-22,共11页
四川盆地X气藏为碳酸盐岩储层,储层层间及层内都具有较强的非均质性,是气藏储量计算面临的困难之一。针对此问题,本文采用实验方法支撑储量计算,首先通过实验测量得到气藏各小层岩心的孔隙度、渗透率等基础物性参数,将小层渗透率校正为... 四川盆地X气藏为碳酸盐岩储层,储层层间及层内都具有较强的非均质性,是气藏储量计算面临的困难之一。针对此问题,本文采用实验方法支撑储量计算,首先通过实验测量得到气藏各小层岩心的孔隙度、渗透率等基础物性参数,将小层渗透率校正为克氏渗透率,并根据物性差异将储层分类为孔隙型储层、孔隙-孔洞型储层,再通过产能模拟实验计算得到气藏工业产能对应的有效储层孔隙度和渗透率等储层物性下限。继而通过液膜厚度实验测得各目标储层的液膜厚度,并结合压汞实验测得的孔径分布曲线,得到有效储层中含烃孔隙体积比例,最后通过地质储量计算公式得到气藏储量。研究结果表明:①利用基础物性测试实验、产能模拟实验、水膜厚度实验等实验方法,确定储层物性下限以及有效孔隙体积比例,为气藏储量计算奠定基础,X气藏有效储层孔隙度下限为1.21%~1.56%;②气藏有效储层中含烃孔隙体积比例范围在42.62%~67.73%,通过地质储量计算公式可得到该气藏的有效储量;③该方法对于非均质性较强的碳酸盐岩储层气藏的储量确定具有理论意义和现场指导意义。 展开更多
关键词 碳酸盐岩 强非均质性 产能模拟实验 液膜厚度实验 孔隙度下限 渗透率下限 有效储层
下载PDF
强夯动荷载作用方向对黄土边坡稳定性的影响分析 被引量:1
18
作者 吴丙权 倪万魁 +2 位作者 拓文鑫 任思远 陈军廷 《振动与冲击》 EI CSCD 北大核心 2024年第1期283-289,共7页
为进一步研究强夯对周边黄土边坡稳定性的影响,采用极限平衡圆弧条分法对强夯作用下的边坡安全系数进行推导计算。结合工程实例,使用TC-4850爆破测振仪对现场监测点进行加速度测试。考虑高程差和测点距离的共同影响,采用MATLAB编程对现... 为进一步研究强夯对周边黄土边坡稳定性的影响,采用极限平衡圆弧条分法对强夯作用下的边坡安全系数进行推导计算。结合工程实例,使用TC-4850爆破测振仪对现场监测点进行加速度测试。考虑高程差和测点距离的共同影响,采用MATLAB编程对现场数据进行多元回归分析,求出强夯作用下边坡质点振动加速度解析式。在求得最小安全系数的基础上,研究不同强夯动荷载方向对黄土边坡稳定性的影响。研究结果表明:在相同荷载作用下,强夯动荷载方向与水平轴正方向夹角为0°、45°、60°、270°、315°、330°、360°时,安全系数均小于等于1.00,且随着拟静力系数不断增大,安全系数越来越小。强夯动荷载方向与水平轴正方向夹角为90°、135°、150°、180°、225°、240°时,安全系数均大于1.05。随着拟静力系数不断增大,安全系数也随之增大。该方法简单易行,便于计算,可用于黄土边坡实际工程。 展开更多
关键词 极限平衡 强夯动荷载方向 安全系数 拟静力系数
下载PDF
粒子群自进化算法求解物流装箱问题
19
作者 赵崟 王小平 +2 位作者 臧铁钢 金将 姜世阔 《物流技术》 2024年第3期52-69,共18页
为了解决当今物流行业中装载货物类型为强异构的情况,提高装载填充率和效率,提出了一种求解三维装箱问题的元启发式算法——粒子群自进化算法。算法包含两部分:极限点构造启发式算法和粒子群自进化规则。极限点构造启发式算法引入了极... 为了解决当今物流行业中装载货物类型为强异构的情况,提高装载填充率和效率,提出了一种求解三维装箱问题的元启发式算法——粒子群自进化算法。算法包含两部分:极限点构造启发式算法和粒子群自进化规则。极限点构造启发式算法引入了极限点的概念,利用新的极值点思想推导出了三维装箱问题的启发式算法。粒子群自进化规则提出了在货物装载序列中表示粒子的方法,推导了粒子间交叉、变异算子,在极限点构造启发式算法的基础上不断迭代进化完成货物的装载。通过不同结果的比对,证明该算法显著提高了物流装载的空间利用率,强异构货物的平均装载率达到了85%,验证了算法在强异构货物下的有效性与优越性,并给出了货物装载的三维模型。由于实际测试集的缺少,分别为机腹仓装载类和集装板类模型提出了实例生成器,通过生成器的测试集验证了算法在实际应用中的紧凑性、实用性和快捷性。 展开更多
关键词 三维装箱问题 强异构装载 物流运输 极点法 粒子群算法 启发式算法
下载PDF
马氏环境中马氏链的一类强极限定理 被引量:23
20
作者 李应求 王苏明 胡杨利 《数学进展》 CSCD 北大核心 2008年第5期539-550,共12页
利用分析方法研究了马氏环境中马氏链的若干强极限定理.得到了关于此种链四元函数的一个强极限定理.作为推论,得到了马氏环境中马氏链相对熵密度的几个极限性质,将Shannon定理推广到了马氏环境中马氏链的情况.
关键词 马氏环境 马氏链 强极限 相对熵密度
下载PDF
上一页 1 2 16 下一页 到第
使用帮助 返回顶部