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On Weighted Possibilistic Mean,Variance and Correlation of Interval-valued Fuzzy Numbers
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作者 ZHANG QIAN-SHENG AND JIANG SHENG-YI 《Communications in Mathematical Research》 CSCD 2010年第2期105-118,共14页
In this paper, the concept of weighted possibilistic mean of interval- valued fuzzy number is first introduced. Further, the notions of weighted possibilistic variance, covariance and correlation of interval-valued fu... In this paper, the concept of weighted possibilistic mean of interval- valued fuzzy number is first introduced. Further, the notions of weighted possibilistic variance, covariance and correlation of interval-valued fuzzy numbers are presented. Meantime, some important properties of them and relationships between them are studied. 展开更多
关键词 Interval-valued fuzzy number weighted possibilistic mean weighted possibilistic variance weighted possibilistic correlation
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基于mean-variance的服务集群负载均衡方法 被引量:7
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作者 包晓安 魏雪 +2 位作者 陈磊 胡国亨 张娜 《电信科学》 北大核心 2017年第1期1-8,共8页
大量并发请求任务进行分配时,负载调度机制是通过最小化响应时间及最大化节点利用率实现网络中节点的负载均衡,在基于遗传算法的负载均衡算法中,适应度函数设计对服务集群负载均衡效率产生重要的影响。对此提出了一种基于mean-variance... 大量并发请求任务进行分配时,负载调度机制是通过最小化响应时间及最大化节点利用率实现网络中节点的负载均衡,在基于遗传算法的负载均衡算法中,适应度函数设计对服务集群负载均衡效率产生重要的影响。对此提出了一种基于mean-variance的服务集群负载均衡方法对适应度函数进行优化,采用投资组合选择模型mean-variance进行最小化响应时间,以得到每个服务器资源利用率的权重,从而获得最优的分配组合,进而提高适应度函数的准确性和有效性。在不同服务环境下与其他模型进行比较,仿真结果表明,本文的负载均衡算法在节点利用率和响应时间方面使服务集群得到了更好的均衡。 展开更多
关键词 负载均衡 mean-variance模型 遗传算法 负载调度
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A Number Theoretic Function and Its Mean Value Computation 被引量:1
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作者 李海龙 杨倩丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期53-56,共4页
Let p be a prime, n be any positiv e integer, α(n,p) denotes the power of p in the factorization of n! . In this paper, we give an exact computing formula of the mean value ∑ n<Nα(n,p).
关键词 number theoretic function mean value computing formula
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摩擦市场条件下的Mean-Variance-Skewness模型
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作者 周洪涛 王宗军 曾宇容 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第6期122-124,共3页
在投资组合选择模型中考虑了资产收益率分布中正的偏度水平,并通过引入一些市场摩擦因素建立了摩擦市场条件下的Mean-Variance-Skewness模型.提出了一个新的遗传算法加速其搜索收敛过程,解决了该模型的计算复杂性问题.在该模型框架内对... 在投资组合选择模型中考虑了资产收益率分布中正的偏度水平,并通过引入一些市场摩擦因素建立了摩擦市场条件下的Mean-Variance-Skewness模型.提出了一个新的遗传算法加速其搜索收敛过程,解决了该模型的计算复杂性问题.在该模型框架内对交易费用和税收等市场摩擦因素进行了敏感性分析.研究证明资产收益率分布的偏度水平是与投资者的决策相关的,市场摩擦因素对投资者的决策行为也有直接的影响.因此,考虑摩擦市场条件下基于正偏度水平偏好的最优投资组合模型对投资者有很强的实践指导价值. 展开更多
关键词 资本市场 mean-variance-Skewness模型 摩擦市场 遗传算法
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THE SCHUR CONVEXITY OF GINI MEAN VALUES IN THE SENSE OF HARMONIC MEAN 被引量:4
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作者 夏卫锋 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1103-1112,共10页
We prove that the Gini mean values S(a,b; x,y) are Schur harmonic convex with respect to (x,y)∈(0,∞)×(0,∞) if and only if (a, b) ∈{(a, b):a≥0,a ≥ b,a+b+1≥0}∪{(a,b):b≥0,b≥a,a+b+1≥0} ... We prove that the Gini mean values S(a,b; x,y) are Schur harmonic convex with respect to (x,y)∈(0,∞)×(0,∞) if and only if (a, b) ∈{(a, b):a≥0,a ≥ b,a+b+1≥0}∪{(a,b):b≥0,b≥a,a+b+1≥0} and Schur harmonic concave with respect to (x,y) ∈ (0,∞)×(0,∞) if and only if (a,b)∈{(a,b):a≤0,b≤0,a|b|1≤0}. 展开更多
关键词 Gini mean values Schur convex Schur harmonic convex
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A novel noise reduction technique for underwater acoustic signals based on complete ensemble empirical mode decomposition with adaptive noise,minimum mean square variance criterion and least mean square adaptive filter 被引量:8
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作者 Yu-xing Li Long Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期543-554,共12页
Underwater acoustic signal processing is one of the research hotspots in underwater acoustics.Noise reduction of underwater acoustic signals is the key to underwater acoustic signal processing.Owing to the complexity ... Underwater acoustic signal processing is one of the research hotspots in underwater acoustics.Noise reduction of underwater acoustic signals is the key to underwater acoustic signal processing.Owing to the complexity of marine environment and the particularity of underwater acoustic channel,noise reduction of underwater acoustic signals has always been a difficult challenge in the field of underwater acoustic signal processing.In order to solve the dilemma,we proposed a novel noise reduction technique for underwater acoustic signals based on complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN),minimum mean square variance criterion(MMSVC) and least mean square adaptive filter(LMSAF).This noise reduction technique,named CEEMDAN-MMSVC-LMSAF,has three main advantages:(i) as an improved algorithm of empirical mode decomposition(EMD) and ensemble EMD(EEMD),CEEMDAN can better suppress mode mixing,and can avoid selecting the number of decomposition in variational mode decomposition(VMD);(ii) MMSVC can identify noisy intrinsic mode function(IMF),and can avoid selecting thresholds of different permutation entropies;(iii) for noise reduction of noisy IMFs,LMSAF overcomes the selection of deco mposition number and basis function for wavelet noise reduction.Firstly,CEEMDAN decomposes the original signal into IMFs,which can be divided into noisy IMFs and real IMFs.Then,MMSVC and LMSAF are used to detect identify noisy IMFs and remove noise components from noisy IMFs.Finally,both denoised noisy IMFs and real IMFs are reconstructed and the final denoised signal is obtained.Compared with other noise reduction techniques,the validity of CEEMDAN-MMSVC-LMSAF can be proved by the analysis of simulation signals and real underwater acoustic signals,which has the better noise reduction effect and has practical application value.CEEMDAN-MMSVC-LMSAF also provides a reliable basis for the detection,feature extraction,classification and recognition of underwater acoustic signals. 展开更多
关键词 Underwater acoustic signal Noise reduction Empirical mode decomposition(EMD) Ensemble EMD(EEMD) Complete EEMD with adaptive noise(CEEMDAN) Minimum mean square variance criterion(MMSVC) Least mean square adaptive filter(LMSAF) Ship-radiated noise
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The Asymptotic Property of Generalized Taylor Remainder "Mean Value Point" 被引量:4
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作者 RENLi-shun ZHANGCai-yu 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期314-318,共5页
This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p... This paper discussed asymptotic property of Taylor remainder 'mean value point' in normed Linear space. The asymptotic progerty of 'mean value point' is solved when f(n+i)(x0)h(n+i) = 0(i = 1, 2,..., p - 1) and f(n+p)(x0)h(h+p) don't exist. Meanwhile, achieve more general asymptotic estimation formula. Make many former results are just because of special case of the pager. 展开更多
关键词 FUNCTIONAL F-derivative Gα-derivative mean value point assymptotic property
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Some Hybrid Mean Values of a New Number Theoretic Function 被引量:1
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作者 REN Gang-lian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期325-329,共5页
Let p and q be two distinct primes, epq(n) denotes the largest exponent of power pq which divides n. In this paper, we study the mean value properties of function epq(n), and give some hybrid mean value formulas f... Let p and q be two distinct primes, epq(n) denotes the largest exponent of power pq which divides n. In this paper, we study the mean value properties of function epq(n), and give some hybrid mean value formulas for epq(n) and Dirichlet divisor function d(n). Key words: largest exponent; asymptotic formula; hybrid mean value; Dirichlet divisor function d(n) 展开更多
关键词 largest exponent asymptotic formula hybrid mean value Dirichlet divisor function d(n)
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MARKOV-MODULATED MEAN-VARIANCE PROBLEM FOR AN INSURER 被引量:2
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作者 王伟 毕俊娜 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1051-1061,共11页
In this paper, we consider an insurance company which has the option of investing in a risky asset and a risk-free asset, whose price parameters are driven by a finite state Markov chain. The risk process of the insur... In this paper, we consider an insurance company which has the option of investing in a risky asset and a risk-free asset, whose price parameters are driven by a finite state Markov chain. The risk process of the insurance company is modeled as a diffusion process whose diffusion and drift parameters switch over time according to the same Markov chain. We study the Markov-modulated mean-variance problem for the insurer and derive explicitly the closed form of the efficient strategy and efficient frontier. In the case of no regime switching, we can see that the efficient frontier in our paper coincides with that of [10] when there is no pure jump. 展开更多
关键词 Markov chain mean-variance efficient strategy efficient frontier Lagrange multiplier
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基于Mean-Variance-CVaR准则的保险公司最优资产配置与再保险策略 被引量:2
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作者 赵霞 时雨 《应用概率统计》 CSCD 北大核心 2020年第5期536-550,共15页
本文研究了连续时间下保险公司基于均值-方差-CVaR准则选择最优资产配置和再保险策略的问题.我们运用鞅方法求解优化问题并得到了相应的显示解.基于数值模拟,我们分析了在不同参数值下最优财富、资产配置和再保险策略随市场条件变化而... 本文研究了连续时间下保险公司基于均值-方差-CVaR准则选择最优资产配置和再保险策略的问题.我们运用鞅方法求解优化问题并得到了相应的显示解.基于数值模拟,我们分析了在不同参数值下最优财富、资产配置和再保险策略随市场条件变化而变化的趋势. 展开更多
关键词 资产配置 再保险策略 mean-variance-CVaR准则 鞅方法
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Portfolio Choice under the Mean-Variance Model with Parameter Uncertainty 被引量:1
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作者 何朝林 许倩 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期498-503,共6页
Assuming the investor is uncertainty-aversion,the multiprior approach is applied to studying the problem of portfolio choice under the uncertainty about the expected return of risky asset based on the mean-variance mo... Assuming the investor is uncertainty-aversion,the multiprior approach is applied to studying the problem of portfolio choice under the uncertainty about the expected return of risky asset based on the mean-variance model. By introducing a set of constraint constants to measure uncertainty degree of the estimated expected return,it built the max-min model of multi-prior portfolio,and utilized the Lagrange method to obtain the closed-form solution of the model,which was compared with the mean-variance model and the minimum-variance model; then,an empirical study was done based on the monthly returns over the period June 2011 to May 2014 of eight kinds of stocks in Shanghai Exchange 50 Index. Results showed,the weight of multi-prior portfolio was a weighted average of the weight of mean-variance portfolio and that of minimumvariance portfolio; the steady of multi-prior portfolio was strengthened compared with the mean-variance portfolio; the performance of multi-prior portfolio was greater than that of minimum-variance portfolio. The study demonstrates that the investor can improve the steady of multi-prior portfolio as well as its performance for some appropriate constraint constants. 展开更多
关键词 portfolio choice mean-variance model parameter uncertainty multi-prior approach constraint constant
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Use of Support Vector Regression Based on Mean Impact Value Model to Identify Active Compounds in a Combination of Curcuma longa L.and Glycyrrhiza extracts 被引量:3
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作者 Jianlan Jiang Qingjie Tan +2 位作者 Weifeng Li Xinyun Du Ningzhi Liu 《Transactions of Tianjin University》 EI CAS 2017年第3期237-244,共8页
A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of HeLa cells in a combination of turmeric (Curcuma longa L.) and liq... A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of HeLa cells in a combination of turmeric (Curcuma longa L.) and liquorice (Glycyrrhiza) extracts. The quantitative chemical fingerprint from 50 batches of turmeric and liquorice extracts was established using high performance liquid chromatography hyphenated to an ultraviolet visible detector. Qualitative results were obtained using ultra performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. A total of 46 peaks (peaks 1–15 from turmeric and 16–46 from liquorice) were selected as “common peaks” for analysis. The inhibitory effect of the combined extracts on HeLa cells was measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. It was found that 15 compounds (peaks: 8, 12, 30, 24, 46, 11, 14, 9, 3, 1, 44, 18, 7, 45 and 43) possessing high absolute MIV exhibited a significant correlation with the cytotoxicity against HeLa cells; most of these have already been confirmed with potential cytotoxicity in previous research. The important potential application of the present model can be extended to help discover active compounds from complex herbal medicine prior to traditional bioassay-guided separation. It is considered that this could be a useful tool for re-developing herbal medicine based on the use of these active compounds. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 BIOASSAY Electrospray ionization Food products High performance liquid chromatography Ionization of liquids Liquid chromatography Mass spectrometry Medicine Plant extracts Regression analysis
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Fatigue Damage Assessment by Considering Mean Value Effect in Frequency Domain
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作者 丁红岩 朱奇 张浦阳 《Transactions of Tianjin University》 EI CAS 2015年第2期161-166,共6页
Fatigue damage assessment is carried out considering mean value effect by applying four criteria of failure. Three frequency domain methods, i.e., level crossing counting(LCC), range counting(RC) and a new proposed me... Fatigue damage assessment is carried out considering mean value effect by applying four criteria of failure. Three frequency domain methods, i.e., level crossing counting(LCC), range counting(RC) and a new proposed method, are applied. The core of frequency domain method is the construction of probability density function for the mean stress and stress range of the stress process. The applicability of these frequency domain methods are inspected by comparing with time domain method. Numerical simulations verify the applicability of LCC and the proposed method, while RC gives poor estimations. 展开更多
关键词 FATIGUE mean value EFFECT S-N CURVE frequency DOMAIN rainflow COUNTING
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THE MEAN VALUE THEOREM AND CONVERSE THEOREM OF ONE CLASS THE FOURTH-ORDER PARTIAL DIFFERENTIAL EQUATIONS
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作者 同小军 同登科 陈绵云 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第6期717-723,共7页
For the formal presentation about the definite problems of ultra-hyperbolic equations, the famous Asgeirsson mean value theorem has answered that Cauchy problems are ill-posed to ultra-hyperbolic partial differential ... For the formal presentation about the definite problems of ultra-hyperbolic equations, the famous Asgeirsson mean value theorem has answered that Cauchy problems are ill-posed to ultra-hyperbolic partial differential equations of the second-order. So it is important to develop Asgeirsson mean value theorem. The mean value of solution for the higher order equation hay been discussed primarily and has no exact result at present. The mean value theorem for the higher order equation can be deduced and satisfied generalized biaxial symmetry potential equation by using the result of Asgeirsson mean value theorem and the properties of derivation and integration. Moreover, the mean value formula can be obtained by using the regular solutions of potential equation and the special properties of Jacobi polynomials. Its converse theorem is also proved. The obtained results make it possible to discuss on continuation of the solutions and well posed problem. 展开更多
关键词 Asgeirsson mean value theorem generalized biaxial symmetry potential equation Jacobi polynomials
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Hybrid Mean Value of the Hyper Cochrane Sums
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作者 ZHANG TIAN-PING 《Communications in Mathematical Research》 CSCD 2009年第4期329-339,共11页
The main purpose of this paper is to use the analytic methods to study the hybrid mean value involving the hyper Cochrane sums, and give several sharp asymptotic formulae.
关键词 hyper Cochrane sum hyper-Kloosterman sum hybrid mean value
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Mean Values of the Hardy Sum
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作者 王晓瑛 岳霞霞 《Chinese Quarterly Journal of Mathematics》 2017年第1期16-33,共18页
Let p≥5 be a prime. For any integer h, the Hardy sum is defined by H(h,p)=sum((-1)^(j+1+[(hj)/p]))from (p-1) to (j=1) which is related to the classical Dedekind sum. The mean values of the Hardy sum in short interval... Let p≥5 be a prime. For any integer h, the Hardy sum is defined by H(h,p)=sum((-1)^(j+1+[(hj)/p]))from (p-1) to (j=1) which is related to the classical Dedekind sum. The mean values of the Hardy sum in short intervals are studied by using the mean value theorems of Dirichlet L-functions. 展开更多
关键词 Dedekind sum Hardy sum mean value Dirichlet L-function
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Improving Queuing System Throughput Using Distributed Mean Value Analysis to Control Network Congestion
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作者 Faisal Shahzad Muhammad Faheem Mushtaq +3 位作者 Saleem Ullah M. Abubakar Siddique Shahzada Khurram Najia Saher 《Communications and Network》 2015年第1期21-29,共9页
In this paper, we have used the distributed mean value analysis (DMVA) technique with the help of random observe property (ROP) and palm probabilities to improve the network queuing system throughput. In such networks... In this paper, we have used the distributed mean value analysis (DMVA) technique with the help of random observe property (ROP) and palm probabilities to improve the network queuing system throughput. In such networks, where finding the complete communication path from source to destination, especially when these nodes are not in the same region while sending data between two nodes. So, an algorithm is developed for single and multi-server centers which give more interesting and successful results. The network is designed by a closed queuing network model and we will use mean value analysis to determine the network throughput (b) for its different values. For certain chosen values of parameters involved in this model, we found that the maximum network throughput for &beta;≥0.7?remains consistent in a single server case, while in multi-server case for &beta;≥ 0.5?throughput surpass the Marko chain queuing system. 展开更多
关键词 Network CONGESTION THROUGHPUT QUEUING System DISTRIBUTED mean value Analysis
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On the Mean Value of the Infinite Order Legendre Series
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作者 王安斌 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期6-12, ,共7页
In this paper, we studies the relations between the mean value and the maximun norm of the infinite order entire functions which defined by legendre series. We obtained that if f(z) is an infinite order entire functio... In this paper, we studies the relations between the mean value and the maximun norm of the infinite order entire functions which defined by legendre series. We obtained that if f(z) is an infinite order entire function with a positive exponenatial lower order. then loaM (α) ~logMδ(α) ~ logMδ(α) (α→+∞). 展开更多
关键词 cntire function mean value order
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On the Mean Difference Variance in Random Samples of Student’s Variables
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作者 Manca Fabio Marin Claudia 《Open Journal of Statistics》 2020年第4期659-663,共5页
The purpose of this paper is to obtain the expression of the sample mean difference variance of the Student’s distributive model. In the 2007 the study of the mean difference variance, after some decades, was resumed... The purpose of this paper is to obtain the expression of the sample mean difference variance of the Student’s distributive model. In the 2007 the study of the mean difference variance, after some decades, was resumed by Campobasso</span><span style="font-family:Verdana;"> [1]</span><span style="font-family:Verdana;">. Using the Nair’s </span><span style="font-family:Verdana;">[2]</span><span style="font-family:Verdana;"> and Lomnicki’s general results</span><span style="font-family:Verdana;"> [3]</span><span style="font-family:Verdana;">, he obtained the variance of sample mean difference for different distributive models (Laplace</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s, triangular, power, logit, Pareto</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s and Gumbel’s model). In addition he extended the knowledge comparing to the ones already known for the other distributive model (normal, rectangular and exponential model). 展开更多
关键词 mean Difference variance Random Sample STUDENT
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On the Lucas Base and Computation of Counting Function Mean Value
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作者 LIHai-long LIUHua-ke 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期84-89,共6页
In this paper, we introduce a new counting function a(m) related to the Lucas number, then use conjecture and induction methods to give an exact formula Ar(N)=α(n), (r=1,2,3) and prove them.
关键词 Lucas sequence Fibonacci sequence mean value counting fuction
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