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A STUDY ON THE WEIGHT FUNCTION OF THE MOVING LEAST SQUARE APPROXIMATION IN THE LOCAL BOUNDARY INTEGRAL EQUATION METHOD 被引量:4
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作者 Long Shuyao Hu De’an (Department of Engineering Mechanics,Hunan University,Changsha 410082,China) 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第3期276-282,共7页
The meshless method is a new numerical technique presented in recent years.It uses the moving least square(MLS)approximation as a shape function.The smoothness of the MLS approximation is determined by that of the bas... The meshless method is a new numerical technique presented in recent years.It uses the moving least square(MLS)approximation as a shape function.The smoothness of the MLS approximation is determined by that of the basic function and of the weight function,and is mainly determined by that of the weight function.Therefore,the weight function greatly affects the accuracy of results obtained.Different kinds of weight functions,such as the spline function, the Gauss function and so on,are proposed recently by many researchers.In the present work,the features of various weight functions are illustrated through solving elasto-static problems using the local boundary integral equation method.The effect of various weight functions on the accuracy, convergence and stability of results obtained is also discussed.Examples show that the weight function proposed by Zhou Weiyuan and Gauss and the quartic spline weight function are better than the others if parameters c and α in Gauss and exponential weight functions are in the range of reasonable values,respectively,and the higher the smoothness of the weight function,the better the features of the solutions. 展开更多
关键词 weight function meshless methods local boundary integral equation method moving least square approximation
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Weak Type Estimates for Intrinsic Square Functions on Weighted Morrey Spaces 被引量:2
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作者 Hua Wang 《Analysis in Theory and Applications》 2013年第2期104-119,共16页
In this paper, we will obtain the weak type estimates of intrinsic square func- tions including the Lusin area integral, Littlewood-Paley g-function and g^-function on the weighted Morrey spaces L^1,k (w) for 0〈k〈... In this paper, we will obtain the weak type estimates of intrinsic square func- tions including the Lusin area integral, Littlewood-Paley g-function and g^-function on the weighted Morrey spaces L^1,k (w) for 0〈k〈 1 and w ∈ A1. 展开更多
关键词 Intrinsic square function weighted Morrey space Ap weight.
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Empty-nest elderly:mahjong and Chinese square dance for improving the cognitive function in the community 被引量:1
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作者 Yue Zhang Marcia A.Petrini 《Frontiers of Nursing》 CAS 2019年第1期71-76,共6页
Objective: The elderly population has proliferated worldwide. The empty-nest family pattern has become predominant among the aging people, and they are more vulnerable to the development of cognitive disorders. Howeve... Objective: The elderly population has proliferated worldwide. The empty-nest family pattern has become predominant among the aging people, and they are more vulnerable to the development of cognitive disorders. However, there is no standardized service in the community nursing care that includes procedures on how to improve the cognitive function of the elderly. Meanwhile, the booming number of empty-nest elderly stimulates the community nurses to assume the responsibility for their care. All of these bring more difficulties and opportunities for community nurses who are dedicated to the prevention of geriatric cognitive disorders.Methods: The authors reviewed the literature related to "empty-nest elderly", "cognitive function","mahjong",and "Chinese square dance" in the Elsevier, Web of Science(WOS), China National Knowledge Infrastructure(CNKI), Springer and PubMed databases. The study illustrates the utility possibility of an efficient and straightforward method for improving the cognitive function among the elderly in the context of community nursing care in China and even in the rest of the world.Results: Mental and physical activity contributes to cognitive fitness and may be beneficial in delaying cognitive decline. Mental activities, such as playing mahjong, and physical activities, such as the Chinese square dance, are common Chinese activities. Both of them can affect cognitive function in some way.Conclusions: China is experiencing one of its most severe aging problems. Community health personnel and related professionals may consider using mahjong and Chinese square dance to promote psychological health in empty-nest elderly individuals in the community. 展开更多
关键词 empty-nest ELDERLY cognitive function MAHJONG CHINESE square DANCE
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BOUNDEDNESS OF STEIN'S SQUARE FUNCTIONS ASSOCIATED TO OPERATORS ON HARDY SPACES 被引量:1
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作者 闫雪芳 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期891-904,共14页
Let (X, d,μ) be a metric measure space endowed with a metric d and a nonnegative Borel doubling measure μ. Let L be a second order non-negative self-adjoint operator on L^2(X). Assume that the semigroup e^-tL ge... Let (X, d,μ) be a metric measure space endowed with a metric d and a nonnegative Borel doubling measure μ. Let L be a second order non-negative self-adjoint operator on L^2(X). Assume that the semigroup e^-tL generated by L satisfies the Davies-Gaffney estimates. Also, assume that L satisfies Plancherel type estimate. Under these conditions, we show that Stein's square function Gδ(L) arising from Bochner-Riesz means associated to L is bounded from the Hardy spaces HL^p(X) to L^p(X) for all 0 〈 p ≤ 1. 展开更多
关键词 Stein's square function non-negative self-adjoint operator Hardy spaces Davies- Gaffney estimate Plancherel type estimate
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Exponential Stability in Mean Square of Neutral Stochastic Functional Differential Equations 被引量:1
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作者 Zhi LI Liping XU 《Journal of Mathematical Research with Applications》 CSCD 2022年第4期413-426,共14页
A novel approach to the exponential stability in mean square of neutral stochastic functional differential equations is presented.Consequently,some new criteria for the exponential stability in mean square of the cons... A novel approach to the exponential stability in mean square of neutral stochastic functional differential equations is presented.Consequently,some new criteria for the exponential stability in mean square of the considered equations are obtained and some known results are improved.Lastly,some examples are investigated to illustrate the theory. 展开更多
关键词 exponential stability in mean square STOCHASTIC functional differential equations NEUTRAL
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Design of Radial Basis Function Network Using Adaptive Particle Swarm Optimization and Orthogonal Least Squares 被引量:1
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作者 Majid Moradi Zirkohi Mohammad Mehdi Fateh Ali Akbarzade 《Journal of Software Engineering and Applications》 2010年第7期704-708,共5页
This paper presents a two-level learning method for designing an optimal Radial Basis Function Network (RBFN) using Adaptive Velocity Update Relaxation Particle Swarm Optimization algorithm (AVURPSO) and Orthogonal Le... This paper presents a two-level learning method for designing an optimal Radial Basis Function Network (RBFN) using Adaptive Velocity Update Relaxation Particle Swarm Optimization algorithm (AVURPSO) and Orthogonal Least Squares algorithm (OLS) called as OLS-AVURPSO method. The novelty is to develop an AVURPSO algorithm to form the hybrid OLS-AVURPSO method for designing an optimal RBFN. The proposed method at the upper level finds the global optimum of the spread factor parameter using AVURPSO while at the lower level automatically constructs the RBFN using OLS algorithm. Simulation results confirm that the RBFN is superior to Multilayered Perceptron Network (MLPN) in terms of network size and computing time. To demonstrate the effectiveness of proposed OLS-AVURPSO in the design of RBFN, the Mackey-Glass Chaotic Time-Series as an example is modeled by both MLPN and RBFN. 展开更多
关键词 RADIAL BASIS function Network ORTHOGONAL Least squareS Algorithm Particle SWARM Optimization Mackey-Glass CHAOTIC Time-Series
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Spin-correlation function of the fully frustrated Ising model and ±J Ising spin glass on a square lattice
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作者 M Y Ali J Poulter 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期549-552,共4页
In this work we study the correlation function of the ground state of a two-dimensional fully frustrated Ising model as well as spin glass. The Pfaffian method is used to calculate free energy and entropy as well as t... In this work we study the correlation function of the ground state of a two-dimensional fully frustrated Ising model as well as spin glass. The Pfaffian method is used to calculate free energy and entropy as well as the correlation function. We estimate the exponent of spin correlation function for the fully frustrated model and spin glass. In this paper an overview of the latest results on the spin correlation function is presented. 展开更多
关键词 spin glass correlation function EXPONENT square lattice
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Boundedness of the Intrinsic Square Function on Grand Variable Herz Spaces
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作者 Jian CHEN Liwei WANG Kexin LIU 《Journal of Mathematical Research with Applications》 CSCD 2022年第6期611-627,共17页
We prove that the intrinsic square function and its commutator are bounded on the Herz space■,where the exponentsαand q are variable.The results are still new even whenα(·)≡αis constant.
关键词 the intrinsic square function COMMUTATOR variable exponent grand space Herz space
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Regional Logistics Demand Forecast Based on Least Square and Radial Basis Function
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作者 WEI Leqin ZHANG Anguo 《Journal of Donghua University(English Edition)》 EI CAS 2020年第5期446-454,共9页
Regional logistics demand forecast is the basis for government departments to make logistics planning and logistics related policies.It has the characteristics of a small amount of data and being nonlinear,so the trad... Regional logistics demand forecast is the basis for government departments to make logistics planning and logistics related policies.It has the characteristics of a small amount of data and being nonlinear,so the traditional prediction method can not guarantee the accuracy of prediction.Taking Xiamen City as an example,this paper selects the primary industry,the secondary industry,the tertiary industry,the total amount of investment in fixed assets,total import and export volume,per capita consumption expenditure,and the total retail sales of social consumer goods as the influencing factors,and uses a combining model least square and radial basis function(LS-RBF)neural network to analyze the related data from years 2000 to 2019,so as to predict the logistics demand from years 2020 to 2024.The model can well fit the training data,and the experimental results obtained from the comparison between the predicted value and the actual value in 2019 show that the error rate is very small.Therefore,the prediction results are reasonable and reliable.This method has high prediction accuracy,and it is suitable for irregular regional logistics demand forecast. 展开更多
关键词 regional logistics demand forecast least square and radial basis function(LS-RBF)
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Mean-square Almost Periodic Random Functions
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作者 江利娜 张传义 《Northeastern Mathematical Journal》 CSCD 2007年第3期215-225,共11页
In this paper, we present a basic theory of mean-square almost periodicity, apply the theory in random differential equation, and obtain mean-square almost periodic solution of some types stochastic differential equat... In this paper, we present a basic theory of mean-square almost periodicity, apply the theory in random differential equation, and obtain mean-square almost periodic solution of some types stochastic differential equation. 展开更多
关键词 mean-square convergence mean-square almost periodic random function Ito integration
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Application of Least Squares Support Vector Machine for Regression to Reliability Analysis 被引量:22
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作者 郭秩维 白广忱 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第2期160-166,共7页
In order to deal with the issue of huge computational cost very well in direct numerical simulation, the traditional response surface method (RSM) as a classical regression algorithm is used to approximate a functiona... In order to deal with the issue of huge computational cost very well in direct numerical simulation, the traditional response surface method (RSM) as a classical regression algorithm is used to approximate a functional relationship between the state variable and basic variables in reliability design. The algorithm has treated successfully some problems of implicit performance function in reliability analysis. However, its theoretical basis of empirical risk minimization narrows its range of applications for... 展开更多
关键词 mechanism design of spacecraft support vector machine for regression least squares support vector machine for regression Monte Carlo method RELIABILITY implicit performance function
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SOME INEQUALITIES OF HERMITE-HADAMARD TYPE FOR s-CONVEX FUNCTIONS 被引量:10
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作者 Mohammad W. Alomari Maslina Darus Ugur S. Kirmaci 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1643-1652,共10页
In this paper several inequalities of the left-hand side of Hermite-Hadamard’s inequality are obtained for s-convex functions.
关键词 convex function s-convex function Hadamard’s inequality
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基于SIMD的Square Root函数高性能实现与优化 被引量:2
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作者 赵永浩 贾海鹏 +1 位作者 张云泉 张思佳 《计算机工程与科学》 CSCD 北大核心 2021年第4期662-669,共8页
在计算机图形学、积分计算和神经网络等应用场景中,平方根函数的高性能实现在构建处理器的基础软件生态中起到了十分重要的作用。随着ARM架构处理器得到广泛的使用,研究ARM架构下的函数快速算法实现变得更加关键。当前大量处理器都采用... 在计算机图形学、积分计算和神经网络等应用场景中,平方根函数的高性能实现在构建处理器的基础软件生态中起到了十分重要的作用。随着ARM架构处理器得到广泛的使用,研究ARM架构下的函数快速算法实现变得更加关键。当前大量处理器都采用了SIMD架构,所以,研究基于SIMD实现高性能函数计算方法具有重要的研究意义和发展前景。因此,对平方根函数进行了高性能的实现与优化。通过分析IEEE 754标准的浮点数在内存中的存储格式,设计了高效的平方根函数算法;然后通过结合平方根倒数和泰勒公式算法,进一步提高了算法精度;最后通过SIMD优化进一步提升了算法性能。实验结果表明,在满足精度的前提下,相比于libm算法库,实现的平方根函数的,性能提高了约7倍,相比于ARM V8提供的计算平方根的指令在性能上提高了约3倍。 展开更多
关键词 平方根函数 SIMD 高性能 数值分析 ARM V8架构
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Temperature prediction control based on least squares support vector machines 被引量:5
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作者 BinLIU HongyeSU +1 位作者 WeihuaHUANG JianCHU 《控制理论与应用(英文版)》 EI 2004年第4期365-370,共6页
A prediction control algorithm is presented based on least squares support vector machines (LS-SVM) model for a class of complex systems with strong nonlinearity. The nonlinear off-line model of the controlled plant i... A prediction control algorithm is presented based on least squares support vector machines (LS-SVM) model for a class of complex systems with strong nonlinearity. The nonlinear off-line model of the controlled plant is built by LS-SVM with radial basis function (RBF) kernel. In the process of system running, the off-line model is linearized at each sampling instant, and the generalized prediction control (GPC) algorithm is employed to implement the prediction control for the controlled plant. The obtained algorithm is applied to a boiler temperature control system with complicated nonlinearity and large time delay. The results of the experiment verify the effectiveness and merit of the algorithm. 展开更多
关键词 Predictive control Least squares support vector machines RBF kernel function Generalized prediction control
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Riemann Boundary Value Problem with Square Roots on an Open Arc 被引量:2
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作者 CHEN Jingsong LU Jiankei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期193-197,共5页
The Riemann boundary value problem with square roots in class h0 when the jumping curve is an open arc in the complex plane is considered. It is solved by reducing it to a classical Riemann boundary value problem so t... The Riemann boundary value problem with square roots in class h0 when the jumping curve is an open arc in the complex plane is considered. It is solved by reducing it to a classical Riemann boundary value problem so that its solutions are obtained in closed form. In certain cases, some auxiliary function ω(z)is introduced. With different choices of ω(z)'s, some interesting examples are illustrated. 展开更多
关键词 square roots open arc Riemann boundary valueproblem canonical function
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Generalizations of Hermite-Hadamard Type Inequalities Involving S-convex Functions 被引量:3
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作者 LIAN Tie-yan TANG Wei 《Chinese Quarterly Journal of Mathematics》 2018年第3期278-286,共9页
Some new Hermite-Hadamard type's integral equations and inequalities are established. The results in [3] and [6] which refined the upper bound of distance between the middle and left of the typical Hermite-Hadamar... Some new Hermite-Hadamard type's integral equations and inequalities are established. The results in [3] and [6] which refined the upper bound of distance between the middle and left of the typical Hermite-Hadamard's integral inequality are generalized. 展开更多
关键词 Hermite-Hadamard's INTEGRAL INEQUALITY s-convex function HSlder's integralinequality
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New predictive control algorithms based on Least Squares Support Vector Machines 被引量:3
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作者 刘斌 苏宏业 褚健 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期440-446,共7页
Used for industrial process with different degree of nonlinearity, the two predictive control algorithms presented in this paper are based on Least Squares Support Vector Machines (LS-SVM) model. For the weakly nonlin... Used for industrial process with different degree of nonlinearity, the two predictive control algorithms presented in this paper are based on Least Squares Support Vector Machines (LS-SVM) model. For the weakly nonlinear system, the system model is built by using LS-SVM with linear kernel function, and then the obtained linear LS-SVM model is transformed into linear input-output relation of the controlled system. However, for the strongly nonlinear system, the off-line model of the controlled system is built by using LS-SVM with Radial Basis Function (RBF) kernel. The obtained nonlinear LS-SVM model is linearized at each sampling instant of system running, after which the on-line linear input-output model of the system is built. Based on the obtained linear input-output model, the Generalized Predictive Control (GPC) algorithm is employed to implement predictive control for the controlled plant in both algorithms. The simulation results after the presented algorithms were implemented in two different industrial processes model; respectively revealed the effectiveness and merit of both algorithms. 展开更多
关键词 Least squares Support Vector Machines Linear kernel function RBF kernel function Generalized predictive control
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Estimating Weibull Parameters Using Least Squares and Multilayer Perceptron vs. Bayes Estimation 被引量:2
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作者 Walid Aydi Fuad S.Alduais 《Computers, Materials & Continua》 SCIE EI 2022年第5期4033-4050,共18页
The Weibull distribution is regarded as among the finest in the family of failure distributions.One of the most commonly used parameters of the Weibull distribution(WD)is the ordinary least squares(OLS)technique,which... The Weibull distribution is regarded as among the finest in the family of failure distributions.One of the most commonly used parameters of the Weibull distribution(WD)is the ordinary least squares(OLS)technique,which is useful in reliability and lifetime modeling.In this study,we propose an approach based on the ordinary least squares and the multilayer perceptron(MLP)neural network called the OLSMLP that is based on the resilience of the OLS method.The MLP solves the problem of heteroscedasticity that distorts the estimation of the parameters of the WD due to the presence of outliers,and eases the difficulty of determining weights in case of the weighted least square(WLS).Another method is proposed by incorporating a weight into the general entropy(GE)loss function to estimate the parameters of the WD to obtain a modified loss function(WGE).Furthermore,a Monte Carlo simulation is performed to examine the performance of the proposed OLSMLP method in comparison with approximate Bayesian estimation(BLWGE)by using a weighted GE loss function.The results of the simulation showed that the two proposed methods produced good estimates even for small sample sizes.In addition,the techniques proposed here are typically the preferred options when estimating parameters compared with other available methods,in terms of the mean squared error and requirements related to time. 展开更多
关键词 Weibull distribution maximum likelihood ordinary least squares MLP neural network weighted general entropy loss function
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Estimation under a Finite Mixture of Exponentiated Exponential Components Model and Balanced Square Error Loss 被引量:1
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作者 Essam K. AL-Hussaini Mohamed Hussein 《Open Journal of Statistics》 2012年第1期28-38,共11页
By exponentiating each of the components of a finite mixture of two exponential components model by a positive parameter, several shapes of hazard rate functions are obtained. Maximum likelihood and Bayes methods, bas... By exponentiating each of the components of a finite mixture of two exponential components model by a positive parameter, several shapes of hazard rate functions are obtained. Maximum likelihood and Bayes methods, based on square error loss function and objective prior, are used to obtain estimators based on balanced square error loss function for the parameters, survival and hazard rate functions of a mixture of two exponentiated exponential components model. Approximate interval estimators of the parameters of the model are obtained. 展开更多
关键词 Finite Mixtures Exponentiated EXPONENTIAL Distribution Maximum Likelihood ESTIMATION Bayes ESTIMATION square ERROR and BALANCED square ERROR LOSS functions Objective Prior
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Application of least squares vector machines in modelling water vapor and carbon dioxide fluxes over a cropland 被引量:1
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作者 秦钟 于强 +2 位作者 李俊 吴志毅 胡秉民 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期491-495,共5页
Least squares support vector machines (LS-SVMs), a nonlinear kemel based machine was introduced to investigate the prospects of application of this approach in modelling water vapor and carbon dioxide fluxes above a s... Least squares support vector machines (LS-SVMs), a nonlinear kemel based machine was introduced to investigate the prospects of application of this approach in modelling water vapor and carbon dioxide fluxes above a summer maize field using the dataset obtained in the North China Plain with eddy covariance technique. The performances of the LS-SVMs were compared to the corresponding models obtained with radial basis function (RBF) neural networks. The results indicated the trained LS-SVMs with a radial basis function kernel had satisfactory performance in modelling surface fluxes; its excellent approximation and generalization property shed new light on the study on complex processes in ecosystem. 展开更多
关键词 Least squares support vector machines (LS-SVMs) Water vapor and carbon dioxide fluxes exchange Radial basis function (RBF) neural networks
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