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Complete Convergenceand Complete Moment Convergence for Weighted Sums of ANA Random Variables
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作者 MENG Bing WU Qunying 《应用概率统计》 CSCD 北大核心 2024年第5期710-724,共15页
In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distri... In this paper,we investigate the complete convergence and complete moment conver-gence for weighted sums of arrays of rowwise asymptotically negatively associated(ANA)random variables,without assuming identical distribution.The obtained results not only extend those of An and Yuan[1]and Shen et al.[2]to the case of ANA random variables,but also partially improve them. 展开更多
关键词 ANA random variables complete convergence complete moment convergence weighted sums
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Blood-based magnetohydrodynamic Casson hybrid nanofluid flow on convectively heated bi-directional porous stretching sheet with variable porosity and slip constraints
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作者 Showkat Ahmad Lone Rawan Bossly +3 位作者 Fuad S.Alduais Afrah Al-Bossly Arshad Khan Anwar Saeed 《Chinese Physics B》 2025年第1期294-306,共13页
Fluid flow through porous spaces with variable porosity has wide-range applications,notably in biomedical and thermal engineering,where it plays a vital role in comprehending blood flow dynamics within cardiovascular ... Fluid flow through porous spaces with variable porosity has wide-range applications,notably in biomedical and thermal engineering,where it plays a vital role in comprehending blood flow dynamics within cardiovascular systems,heat transfer and thermal management systems improve efficiency using porous materials with variable porosity.Keeping these important applications in view,in current study blood-based hybrid nanofluid flow has considered on a convectively heated sheet.The sheet exhibits the properties of a porous medium with variable porosity and extends in both the x and y directions.Blood has used as base fluid in which the nanoparticles of Cu and Cu O have been mixed.Thermal radiation,space-dependent,and thermal-dependent heat sources have been incorporated into the energy equation,while magnetic effects have been integrated into the momentum equations.Dimensionless variables have employed to transform the modeled equations into dimensionless form and facilitating their solution using bvp4c approach.It has concluded in this study that,both the primary and secondary velocities augmented with upsurge in variable porous factor and declined with escalation in stretching ratio,Casson,magnetic,and slip factors along x-and y-axes.Thermal distribution has grown up with upsurge in Casson factor,magnetic factor,thermal Biot number,and thermal/space-dependent heat sources while has retarded with growth in variable porous and stretching ratio factors.The findings of this investigation have been compared with the existing literature,revealing a strong agreement among present and established results that ensured the validation of the model and method used in this work. 展开更多
关键词 hybrid nanofluid Casson fluid MAGNETOHYDRODYNAMICS variable porous space space/thermaldependent heat sources velocity slip and thermal convective conditions
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A novel approach to visual image encryption:2D hyperchaos,variable Josephus,and 3D diffusion
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作者 Yan Hong Xinyan Duan +2 位作者 Jingming Su Zhaopan Wang Shihui Fang 《Chinese Physics B》 2025年第4期335-352,共18页
With the development of the Internet,image encryption technology has become critical for network security.Traditional methods often suffer from issues such as insufficient chaos,low randomness in key generation,and po... With the development of the Internet,image encryption technology has become critical for network security.Traditional methods often suffer from issues such as insufficient chaos,low randomness in key generation,and poor encryption efficiency.To enhance performance,this paper proposes a new encryption algorithm designed to optimize parallel processing and adapt to images of varying sizes and colors.The method begins by using SHA-384 to extract the hash value of the plaintext image,which is then processed to determine the chaotic system’s initial value and block size.The image is padded and divided into blocks for further processing.A novel two-dimensional infinite collapses hyperchaotic map(2DICHM)is employed to generate the intra-block scrambling sequence,while an improved variable Joseph traversal sequence is used for inter-block scrambling.After removing the padding,3D forward and backward shift diffusions,controlled by the 2D-ICHM sequences,are applied to the scrambled image,producing the ciphertext.Simulation results demonstrate that the proposed algorithm outperforms others in terms of entropy,anti-noise resilience,correlation coefficient,robustness,and encryption efficiency. 展开更多
关键词 SHA-384 two-dimensional infinite collapses hyperchaotic map(2D-ICHM) variable Joseph traversal 3D forward shift diffusion
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Neural network analysis for prediction of heat transfer of aqueous hybrid nanofluid flow in a variable porous space with varying film thickness over a stretched surface
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作者 Abeer S Alnahdi Taza Gul 《Chinese Physics B》 2025年第2期316-326,共11页
The high thermal conductivity of the nanoparticles in hybrid nanofluids results in enhanced thermal conductivity associated with their base fluids.Enhanced heat transfer is a result of this high thermal conductivity,w... The high thermal conductivity of the nanoparticles in hybrid nanofluids results in enhanced thermal conductivity associated with their base fluids.Enhanced heat transfer is a result of this high thermal conductivity,which has significant applications in heat exchangers and engineering devices.To optimize heat transfer,a liquid film of Cu and TiO_(2)hybrid nanofluid behind a stretching sheet in a variable porous medium is being considered due to its importance.The nature of the fluid is considered time-dependent and the thickness of the liquid film is measured variable adjustable with the variable porous space and favorable for the uniform flow of the liquid film.The solution of the problem is acquired using the homotopy analysis method HAM,and the artificial neural network ANN is applied to obtain detailed information in the form of error estimation and validations using the fitting curve analysis.HAM data is utilized to train the ANN in this study,which uses Cu and TiO_(2)hybrid nanofluids in a variable porous space for unsteady thin film flow,and it is used to train the ANN.The results indicate that Cu and TiO_(2)play a greater role in boosting the rate. 展开更多
关键词 thin film of Cu and TiO_(2)hybrid nanofluids variable porous space unsteady stretching sheet viscous dissipation heat transfer optimization artificial neural network
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The Influences of Affective Variables on and Implications for English Teaching and Learning
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作者 张莹 《海外英语》 2014年第23期286-288,共3页
Admittedly cognitive variables such as intelligence and aptitude exert great impact on English learning. Affective variables, however, are of intense importance in determining English learning as well, because affect ... Admittedly cognitive variables such as intelligence and aptitude exert great impact on English learning. Affective variables, however, are of intense importance in determining English learning as well, because affect is a starting machine that sets the learning mechanism in motion and learning will run into difficulty if affect does not work properly. Besides, there is mounting interest in exploring the affective domain. Therefore, this paper focuses upon the analyses of four affective variables(attitude, motivation, self-esteem and anxiety) that have bearings on English learning and sets forth Implications for English teaching. 展开更多
关键词 AFFECTIVE variables ENGLISH TEACHING and learning
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Real Time Study and Related Variables
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作者 武小青 《海外英语》 2016年第18期208-209,共2页
This paper first, illustrates the advantages of applying real time study to linguistic researches. Second, this paper also compares linguistic variables with linguistic variant; nasality, stronger constraint and weake... This paper first, illustrates the advantages of applying real time study to linguistic researches. Second, this paper also compares linguistic variables with linguistic variant; nasality, stronger constraint and weaker constraint have been clearly defined as well. 展开更多
关键词 real time linguistic variable CONSTRAINT NASALITY
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ON CHOVER'S LIL FOR THE WEIGHTED SUMS OF STABLE RANDOM VARIABLES 被引量:5
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作者 陈平炎 余旌胡 《Acta Mathematica Scientia》 SCIE CSCD 2003年第1期74-82,共9页
Let {Xn,n ≥ 1} be a sequence of α-stable random variables(0 < α < 2), {ani,1 ≤ i≤ n, n≥1} be an array of constant real numbers. Under some restriction of {ani,1 ≤ i ≤ n,n≥1}, the authors discuss the int... Let {Xn,n ≥ 1} be a sequence of α-stable random variables(0 < α < 2), {ani,1 ≤ i≤ n, n≥1} be an array of constant real numbers. Under some restriction of {ani,1 ≤ i ≤ n,n≥1}, the authors discuss the integral test for the weighted partial sums {Σi=1naniXi,n ≥ 1}, and obtain the Chover's laws of iterated logarithm(LIL) as corollaries. 展开更多
关键词 Stable random variable integral test LIL
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SOME LIMIT THEOREMS FOR SEQUENCES OF PAIRWISE NQD RANDOM VARIABLES 被引量:8
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作者 甘师信 陈平炎 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期269-281,共13页
In this article, the authors study some limit properties for sequences of pairwise NQD random variables, which are not necessarily identically distributed. They obtain Baum and Katz complete convergence and the strong... In this article, the authors study some limit properties for sequences of pairwise NQD random variables, which are not necessarily identically distributed. They obtain Baum and Katz complete convergence and the strong stability of Jamison's weighted sums for pairwise NQD random variables, which may have different distributions. Some wellknown results are improved and extended. 展开更多
关键词 Pairwise NQD random variable sequence convergence in probability almost sure convergence complete convergence strong stability
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LARGE DEVIATIONS AND MODERATE DEVIATIONS FOR m-NEGATIVELY ASSOCIATED RANDOM VARIABLES 被引量:8
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作者 胡亦钧 明瑞星 杨文权 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期886-896,共11页
M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large devi... M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large deviation principles and moderate deviation upper bounds for stationary m-negatively associated random variables are proved. Kolmogorov-type and Marcinkiewicz-type strong laws of large numbers as well as the three series theorem for m-negatively associated random variables are also given. 展开更多
关键词 negatively associated random variables stationary sequence strong law of large numbers large deviations moderate deviations
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Topology identification for a class of complex dynamical networks using output variables 被引量:4
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作者 Fan Chun-Xia Wan You-Hong Jiang Guo-Ping 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期193-201,共9页
A problem of topology identification for complex dynamical networks is investigated in this paper. An adaptive observer is proposed to identify the topology of a complex dynamical networks based on the Lyapunov stabil... A problem of topology identification for complex dynamical networks is investigated in this paper. An adaptive observer is proposed to identify the topology of a complex dynamical networks based on the Lyapunov stability theory. Here the output of the network and the states of the observer are used to construct the updating law of the topology such that the communication resources from the network to its observer are saved. Some convergent criteria of the adaptive observer are derived in the form of linear inequality matrices. Several numerical examples are shown to demonstrate the effectiveness of the proposed observer. 展开更多
关键词 complex dynamical networks topology identification adaptive observer output variables
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The Integer Parts of a Nonlinear Form with Integer Variables and Mixed Powers 2 and 4 被引量:3
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作者 LI Wei-ping GE Wen-xu WANG Tian-ze 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期317-322,共6页
The present paper proved that if λ1, λ2, λ3 are positive real numbers, λ1/λ2 is irrational. Then, the integer parts of λ1x12+ λ2x22+ λ3x34 are prime infinitely often for natural numbers x1, x2, x3.
关键词 INTEGER variables DIOPHANTINE APPROXIMATION Davenport-Heilbronn method
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ON THE LIMITING BEHAVIOR OF THE MAXIMUM PARTIAL SUMS FOR ARRAYS OF ROWWISE NA RANDOM VARIABLES 被引量:3
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作者 甘师信 陈平炎 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期283-290,共8页
Let {Xni, 1 ≤ n,i 〈 ∞} be an an array of rowwise NA random variables and {an, n ≥ 1} a sequence of constants with 0 〈 an ↑∞ . The limiting behavior of maximum partial sums 1/an max 1≤k≤n|^k∑i=1 Xni| is inv... Let {Xni, 1 ≤ n,i 〈 ∞} be an an array of rowwise NA random variables and {an, n ≥ 1} a sequence of constants with 0 〈 an ↑∞ . The limiting behavior of maximum partial sums 1/an max 1≤k≤n|^k∑i=1 Xni| is investigated and some new results are obtained. The results extend and improve the corresponding theorems of rowwise independent random variable arrays by Hu and Taylor [1] and Hu and Chang [2]. 展开更多
关键词 NA random variable maximum partial sum complete convergence convergence in probability
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EFFICIENT ESTIMATION OF FUNCTIONAL-COEFFICIENT REGRESSION MODELS WITH DIFFERENT SMOOTHING VARIABLES 被引量:5
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作者 张日权 李国英 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期989-997,共9页
In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the l... In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the local linear technique and the averaged method,the initial estimates of the coefficient functions are given.Second step,based on the initial estimates,the efficient estimates of the coefficient functions are proposed by a one-step back-fitting procedure.The efficient estimators share the same asymptotic normalities as the local linear estimators for the functional-coefficient models with a single smoothing variable in different functions.Two simulated examples show that the procedure is effective. 展开更多
关键词 Asymptotic normality averaged method different smoothing variables functional-coefficient regression models local linear method one-step back-fitting procedure
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On the Strong Laws for Weighted Sums of m-negatively Asso ciated Random Variables 被引量:3
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作者 WU Yong-feng 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期265-273,共9页
In this article, the author establishes the strong laws for linear statistics that are weighted sums of a m-negatively associated(m-NA) random sample. The obtained results extend and improve the result of Qiu and Yang... In this article, the author establishes the strong laws for linear statistics that are weighted sums of a m-negatively associated(m-NA) random sample. The obtained results extend and improve the result of Qiu and Yang in [1] to m-NA random variables. 展开更多
关键词 Marcinkiewicz-Zygmund strong law complete convergence weighted sums m-negatively associated random variable
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On the Strong Rates of Convergence for Arrays of Rowwise Extended Negatively Dependent Random Variables 被引量:2
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作者 ZHENG Lu-lu XU Chen HUANG Xu-feng WANG Xue-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期592-601,共10页
A general result on the strong convergence rate and complete convergence for arrays of rowwise extended negatively dependent random variables is established. As applications, some well-known results on negatively depe... A general result on the strong convergence rate and complete convergence for arrays of rowwise extended negatively dependent random variables is established. As applications, some well-known results on negatively dependent random variables can be easily extended to the case of arrays of rowwise extended negatively dependent random variables. 展开更多
关键词 extended negatively dependent random variables negatively dependent complete convergence
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Some Convergence Results for Sequences of -mixing Random Variables 被引量:3
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作者 PAN Jing ZHU Ye-chun ZOU Wei-yuan WANG Xue-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期111-117,共7页
In this paper, we will present some strong convergence results for sequences of ψ-mixing random variables. The results for sequences of ψ-mixing random variables generalize the corresponding results for independent ... In this paper, we will present some strong convergence results for sequences of ψ-mixing random variables. The results for sequences of ψ-mixing random variables generalize the corresponding results for independent random variable sequences without any extra conditions. 展开更多
关键词 Khintchine-Kolmogorov-type convergence theorem strong law of large numbers ψ-mixing random variables
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SOME LIMIT THEOREMS FOR WEIGHTED SUMS OF ARRAYS OF NOD RANDOM VARIABLES 被引量:2
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作者 甘师信 陈平炎 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2388-2400,共13页
In this paper the authors study the complete, weak and almost sure convergence for weighted sums of NOD random variables and obtain some new limit theorems for weighted sums of NOD random variables, which extend the c... In this paper the authors study the complete, weak and almost sure convergence for weighted sums of NOD random variables and obtain some new limit theorems for weighted sums of NOD random variables, which extend the corresponding theorems of Stout [1], Thrum [2] and Hu et al. [3]. 展开更多
关键词 complete convergence weak convergence almost sure convergence ARRAY weighted sum NOD random variable sequence
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Early Warning of Acute Altitude Sickness by Physiological Variables and Noninvasive Cardiovascular Indicators 被引量:10
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作者 Zongbin Li Chunwei Liu +5 位作者 Jun Guo Yajun Shi Yang Li Jinli Wang Jing Wang Yundai Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2020年第1期13-19,共7页
Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude.Methods One hundred and six Han nation... Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude.Methods One hundred and six Han nationality male individuals were recruited to this research.Dynamic electrocardiogram,treadmill exercise test,echocardiography,routine blood examination and biochemical analysis were performed when subjects at sea level and entering the plateau respectively.Then multiple regression analysis was performed to construct a multiple linear regression equation using the Lake Louise Score as dependent variable to predict the risk factors at sea level related to acute mountain sickness(AMS).Results Approximately 49.05%of the individuals developed AMS.The tricuspid annular plane systolic excursion(22.0+2.66 vs.23.2+3.19 mm,t=l.998,P=0.048)was significantly lower in the AMS group at sea level,while count of eosinophil[(0.264+0.393)×109/L vs.(0.126+0.084)×109/L,t=-2.040,P—0.045],percentage of diflerences exceeding 50 ms between adjacent normal number of intervals(PNN50,9.66%±5.40%vs.6.98%±5.66%,t=-2.229,P=0.028)and heart rate variability triangle index(57.1+16.1 vs.50.6+12.7,t=-2.271,P=0.025)were significantly higher.After acute exposure to high altitude,C-reactive protein(0.098+0.103 vs.0.062+0.045 g/L,t=-2.132,P=0.037),aspartate aminotransferase(19.7+6.7275.17,3±3.95 U/L,t=-2.231,P=0.028)and creatinine(85.1±12.9 vs.77.7±11.2 mmol/L,t=3.162,P=0.002)were significantly higher in the AMS group,while alkaline phosphatase(71.7+18.2 vs.80.6+20.2 U/L,t=2.389,P=0.019),standard deviation of normal-to-normal RR intervals(126.5+35.9 vs.143.3+36.4 ms,t—2.320,P—0.022),ejection time(276.9+50.8 vs.313.8+48.9 ms,t—3.641,P—0.001)and heart rate variability triangle index(37.1+12.9 vs.41.9+11.1,t=2.O2O,P=0.047)were significantly lower.Using the Lake Louise Score as the dependent variable,prediction equation were established to estimate AMS:Lake Louise Score=3.783+0.281Xeosinophil-0.219Xalkaline phosphatase+O.O32XPNN50.Conclusions We elucidated the differences of pl^siological variables as well as noninvasive cardiovascular indicators for subjects after high altitude exposure compared with those at sea level.We also created an acute high altitude reaction early warning equation based on the physiological variables and noninvasive cardiovascular indicators at sea level. 展开更多
关键词 ACUTE ALTITUDE sickness PHYSIOLOGICAL variables NONINVASIVE CARDIOVASCULAR indicators ACUTE high ALTITUDE exposure early warning
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Strong Law of Large Numbers for Array of Rowwise AANA Random Variables 被引量:1
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作者 CHEN Zhi-yong LIU Ting-ting WANG Xue-jun LI Xiao-qin 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期475-485,共11页
In this article, the strong laws of large numbers for array of rowwise asymptotically almost negatively associated(AANA) random variables are studied. Some sufficient conditions for strong laws of large numbers for ar... In this article, the strong laws of large numbers for array of rowwise asymptotically almost negatively associated(AANA) random variables are studied. Some sufficient conditions for strong laws of large numbers for array of rowwise AANA random variables are presented without assumption of identical distribution. Our results extend the corresponding ones for independent random variables to case of AANA random variables. 展开更多
关键词 AANA random variables array of rowwise AANA random variables strong law of large numbers
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The Strong Convergence Properties for Partial Sums of m-NA Random Variables 被引量:2
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作者 WANG Meng-hang PEI Wen-chen +2 位作者 ZHANG Yu-heng YING Han-lu WANG Xue-jun 《Chinese Quarterly Journal of Mathematics》 2018年第2期172-180,共9页
In this paper, by the three series theorem of m-negatively associated(m-NA,in short) random variables and the truncation method of random variables, we mainly investigated the strong convergence properties for partial... In this paper, by the three series theorem of m-negatively associated(m-NA,in short) random variables and the truncation method of random variables, we mainly investigated the strong convergence properties for partial sums of m-NA random variables.In addition, the Khintchine-Kolmogorov convergence theorem and Kolmogorov-type strong law of large numbers for m-NA random variables are also obtained. The results obtained in the paper generalize some corresponding ones for independent random variables and some dependent random variables. 展开更多
关键词 m-NA random variables Three series theorem Strong convergence Kolmogorov-type strong law of large numbers
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