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Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function
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作者 Mokhtar Ellali Mokhtar Bouazza Ashraf M.Zenkour 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期547-561,共15页
Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagati... Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in plates.This work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of FGM.This model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine function.The FGM plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse quadratic.By utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials. 展开更多
关键词 FGM plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function
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The Determination Method of Product Engineering Features Based on Linguistic Variables
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作者 Guo Mao 《Journal of World Architecture》 2024年第1期18-23,共6页
To overcome the problem of imprecise and unclear information in the development of quality functions,a method for determining the priority of engineering features based on mixed linguistic variables is proposed.First,... To overcome the problem of imprecise and unclear information in the development of quality functions,a method for determining the priority of engineering features based on mixed linguistic variables is proposed.First,the evaluation member uses the determined linguistic variable to give the correlation strength evaluation matrix of customer requirements and engineering features.Secondly,the relative importance of the evaluation member and customer requirements are aggregated.Finally,the priority of engineering features is obtained by calculating the deviation.The feasibility and practicability of this method are proven by taking the design of a new product of a long bag low-pressure pulse dust collector as an example. 展开更多
关键词 Quality function deployment Engineering features Linguistic variable Priority ratings
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SOME RESULTS REGARDING PARTIAL DIFFERENTIAL POLYNOMIALS AND THE UNIQUENESS OF MEROMORPHIC FUNCTIONS IN SEVERAL VARIABLES
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作者 刘曼莉 高凌云 房少梅 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期821-838,共18页
In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing sm... In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing small functions.As an application of the value distribution result,we study the defect relation of a nonconstant solution to the partial differential equation.In particular,we give a connection between the Picard type theorem of Milliox-Hayman and the characterization of entire solutions of a partial differential equation. 展开更多
关键词 meromorphic function in several variables Nevanlinna theory partial differ-ential equation total derivative
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 symmetry group group foliation method nonlinear wave equation functional separation of variables
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SPACES OF ANALYTIC FUNCTIONS REPRESENTED BY DIRICHLET SERIES OF TWO COMPLEX VARIABLES 被引量:1
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作者 Hazem Shaba Behnam and G. S. Srivastava (Indian Institule Technology of Roorkee, India) 《Approximation Theory and Its Applications》 2002年第3期1-14,共14页
We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the auth... We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the authors. Under this topology X becomes a Frechet space Apart from finding the characterization of continuous linear functionals, linear transformation on X, we have obtained the necessary and sufficient conditions for a double sequence in X to be a proper bases. 展开更多
关键词 SPACES OF ANALYTIC functionS REPRESENTED BY DIRICHLET SERIES OF TWO COMPLEX variables TEB MATH
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BOUNDARY VALUE PROBLEMS OF CONJUGATE AND GENERALIZED K-HOLOMORPHIC FUNCTIONS IN C^(2)
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作者 Yanyan CUI Chaojun WANG +1 位作者 Yonghong XIE Yuying QIAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1837-1852,共16页
In this paper,conjugate k-holomorphic functions and generalized k-holomorphic functions are defined in the two-dimensional complex space,and the corresponding Riemann boundary value problems and the inverse problems a... In this paper,conjugate k-holomorphic functions and generalized k-holomorphic functions are defined in the two-dimensional complex space,and the corresponding Riemann boundary value problems and the inverse problems are discussed on generalized bicylinders.By the characteristics of the corresponding functions and boundary properties of the Cauchy type singular integral operators with conjugate k-holomorphic kernels,the general solutions and special solutions of the corresponding boundary value problems are studied in a detailed fashion,and the integral expressions of the solutions are obtained. 展开更多
关键词 several complex variables k-holomorphic functions partial difference equations polyanalytic functions
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Disparities in tree mortality among plant functional types(PFTs)in a temperate forest:Insights into size-dependent and PFT-specific patterns
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作者 Man Hu Hang Shi +6 位作者 Rui He Bingbin Wen Haikun Liu Kerong Zhang Xiao Shu Haishan Dang Quanfa Zhang 《Forest Ecosystems》 SCIE CSCD 2024年第4期480-490,共11页
Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This s... Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This study analysed size-dependent tree mortality in a temperate forest,encompassing 46 tree species and 32,565 individuals across different PFTs(i.e.,evergreen conifer vs.deciduous broadleaf species,shade-tolerant vs.shade-intolerant species).By employing all-subset regression procedures and logistic generalized linear mixed-effects models,we identified distinct mortality patterns influenced by biotic and abiotic factors.Our results showed a stable mortality patte rn in eve rgreen conifer species,contrasted by a declining pattern in deciduous broadleaf and shadetolerant,as well as shade-intolerant species,across size classes.The contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size,while the mortality of deciduous broadleaf species was mainly influenced by biotic factors,such as initial diameter at breast height(DBH)and conspecific negative density.For shade-tolerant species,the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence,whereas the mortality of large individuals was subjected to the combined effect of biotic(competition from neighbours)and abiotic factors(i.e.,convexity and pH).As for shade-intolerant species,competition from neighbours was found to be the main driver of tree mortality throughout their growth stages.Thus,these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns,which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems. 展开更多
关键词 Size-dependent tree mortality Plant functional type Neighbourhood competition Topography variables Soil properties
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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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FRACTIONAL INTEGRALS OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES
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作者 Wang Shiming 《Analysis in Theory and Applications》 1993年第1期82-96,共15页
In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the... In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^2-norm.Results obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n. 展开更多
关键词 TH FRACTIONAL INTEGRALS OF PERIODIC functionS OF SEVERAL variables
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A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems
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作者 Scott A. Sarra Derek Musgrave +1 位作者 Marcus Stone Joseph I. Powell 《Journal of Applied Mathematics and Physics》 2024年第7期2559-2573,共15页
Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with... Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used. 展开更多
关键词 Numerical Partial Differential Equations Boundary Value Problems Radial Basis function Methods Ghost Points variable Shape Parameter Least Squares
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Construction of crash prediction model of freeway basic segment based on interactive influence of explanatory variables
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作者 王晓飞 李新伟 +2 位作者 符锌砂 赵立萱 刘小峰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期276-281,共6页
In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomi... In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomial (NB) regression models and three generalized negative binomial (GNB) regression models are built to prove that the interactive influence of explanatory variables plays an important role in fitting goodness. The effective use of the GNB model in analyzing the interactive influence of explanatory variables and predicting freeway basic segments is demonstrated. Among six models, the two models (one is the NB model and the other is the GNB model. ) which consider the interactive influence of the annual average daily traffic (AADT) and length are more reasonable for predicting results. Furthermore, a comprehensive study is carried out to prove that when considering the interactive influence, the NB and GNB models have almost the same fitting performance in estimating the crashes, among which the GNB model is slightly better for prediction performance. 展开更多
关键词 CRASH FREEWAY safety performance function SPF interactive influence of explanatory variables generalized negative binomial (GNB)
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A Method of Gene-Function Annotation Based on Variable Precision Rough Sets 被引量:5
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作者 Zhi-li Pei Xiao-hu Shi +4 位作者 Meng Niu Xu-ning Tang Li-sha Liu Ying Kong Yan-chun Liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第3期177-184,共8页
It is very important in the field of bioinformatics to apply computer to perform the function annotation for new sequenced bio-sequences. Based on GO database and BLAST program, a novel method for the function annotat... It is very important in the field of bioinformatics to apply computer to perform the function annotation for new sequenced bio-sequences. Based on GO database and BLAST program, a novel method for the function annotation of new biological sequences is presented by using the variable-precision rough set theory. The proposed method is applied to the real data in GO database to examine its effectiveness. Numerical results show that the proposed method has better precision, recall-rate and harmonic mean value compared with existing methods. 展开更多
关键词 gene function ANNOTATION variable precision rough set GO BLAST
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The derivative-dependent functional variable separation for the evolution equations 被引量:3
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作者 张顺利 楼森岳 屈长征 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2765-2776,共12页
This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which adm... This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which admits the derivative- dependent functional separable solutions (DDFSSs). We also extend the concept of the DDFSS to cover other variable separation approaches. 展开更多
关键词 derivative-dependent functional variable separation evolution equations generalized conditional symmetry
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Functional Variable Separation for Extended Nonlinear Elliptic Equations 被引量:4
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作者 ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期385-390,共6页
This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the ... This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the generalized conditional symmetry, we obtain complete classification of those equations which admit functional separable solutions (FSSs) and construct some exact FSSs to the resulting equations. 展开更多
关键词 nonlinear elliptic equation functional variable separation generalized conditional symmetry
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Variable Separation and Derivative-Dependent Functional Separable Solutions to Generalized Nonlinear Wave Equations 被引量:3
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作者 ZHANGShun-Li LOUSen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期161-174,共14页
Using the generalized conditional symmetry approach, we obtain a number of new generalized (1+1)-dimensional nonlinear wave equations that admit derivative-dependent functional separable solutions.
关键词 variable separation nonlinear wave derivative-dependent functional separable solution
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A numerical method based on boundary integral equations and radial basis functions for plane anisotropic thermoelastostatic equations with general variable coefficients 被引量:2
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作者 W.T.ANG X.WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第4期551-566,共16页
A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable ... A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable coe?cients. The equations describe the thermoelastic behaviors of nonhomogeneous anisotropic materials with properties that vary smoothly from point to point in space. No restriction is imposed on the spatial variations of the thermoelastic coe?cients as long as all the requirements of the laws of physics are satis?ed. To check the validity and accuracy of the proposed numerical method, some speci?c test problems with known solutions are solved. 展开更多
关键词 elliptic partial differential equation variable coefficient boundary element method radial basis function anisotropic thermoelastostatics
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Multi-attribute group decision making method under 2-dimension uncertain linguistic variables 被引量:3
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作者 JIANG Kexin ZHANG Quan YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1254-1261,共8页
A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their f... A method is proposed to deal with the uncertain multiple attribute group decision making problems,where 2-dimension uncertain linguistic variables(2DULVs)are used as the reliable way for the experts to express their fuzzy subjective evaluation information.Firstly,in order to measure the 2DULVs more accurately,a new method is proposed to compare two 2DULVs,called a score function,while a new function is defined to measure the distance between two 2DULVs.Secondly,two optimization models are established to determine the weight of experts and attributes based on the new distance formula and a weighted average operator is used to determine the comprehensive evaluation value of each alternative.Then,a score function is used to determine the ranking of the alternatives.Finally,the effectiveness of the proposed method is proved by an illustrated example. 展开更多
关键词 2-dimension uncertain linguistic variables(2DULVs) multi-attribute group decision making problem score function distance formula
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The Jacobi elliptic function-like exact solutions to two kinds of KdV equations with variable coefficients and KdV equation with forcible term 被引量:10
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作者 套格图桑 斯仁到尔吉 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2809-2818,共10页
By use of an auxiliary equation and through a function transformation, the Jacobi elliptic function wave-like solutions, the degenerated soliton-like solutions and the triangle function wave solutions to two kinds of ... By use of an auxiliary equation and through a function transformation, the Jacobi elliptic function wave-like solutions, the degenerated soliton-like solutions and the triangle function wave solutions to two kinds of Korteweg de Vries (KdV) equations with variable coefficients and a KdV equation with a forcible term are constructed with the help of symbolic computation system Mathematica, where the new solutions are also constructed. 展开更多
关键词 auxiliary equation KdV equation with variable coefficients KdV equation with a forcible term Jacobi elliptic function-like exact solutions
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A NEW METHOD FOR STRUCTURAL TOPOLOGICAL OPTIMIZATION BASED ON THE CONCEPT OF INDEPENDENT CONTINUOUS VARIABLES AND SMOOTH MODEL 被引量:83
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作者 隋允康 杨德庆 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1998年第2期179-185,共7页
A concept of the independent-continuous topological variable is proposed to establish its corresponding smooth model of structural topological optimization. The method can overcome difficulties that are encountered in... A concept of the independent-continuous topological variable is proposed to establish its corresponding smooth model of structural topological optimization. The method can overcome difficulties that are encountered in conventional models and algorithms for the optimization of the structural topology. Its application to truss topological optimization with stress and displacement constraints is satisfactory, with convergence faster than that of sectional optimizations. 展开更多
关键词 structural topological optimization smooth model adaptive algorithm truss structure independent-continuous variable filter function
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On Humbert Matrix Polynomials of Two Variables
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作者 Ghazi S. Khammash A. Shehata 《Advances in Pure Mathematics》 2012年第6期423-427,共5页
In this paper we introduce Humbert matrix polynomials of two variables. Some hypergeometric matrix representations of the Humbert matrix polynomials of two variables, the double generating matrix functions and expansi... In this paper we introduce Humbert matrix polynomials of two variables. Some hypergeometric matrix representations of the Humbert matrix polynomials of two variables, the double generating matrix functions and expansions of the Humbert matrix polynomials of two variables in series of Hermite polynomials are given. Results of Gegenbauer ma-trix polynomials of two variables follow as particular cases of Humbert matrix polynomials of two variables. 展开更多
关键词 HUMBERT MATRIX POLYNOMIALS of TWO variables HYPERGEOMETRIC MATRIX function MATRIX functional Calculus
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