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Study on the methods to calculate the numbers of elements in every period in the periodic table
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作者 WU Zhi-fu DENG De-hua +2 位作者 SHEN Yu-hua XIE An-jian CHEN Zhang-xu 《Journal of Chemistry and Chemical Engineering》 2008年第4期71-74,共4页
The previous methods of figuring the numbers of chemical elements is summed up in this paper. Based on that, another two creative calculative methods are introduced as well.
关键词 the periodic table of elements the odd number theeven number calculative methods
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Ramsey numbers r(K_(1, 4), G) for all three-partite graphs G of order six
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作者 顾华 宋洪雪 刘向阳 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期378-380,共3页
In this paper, we use a combinatorial analysis method. In the complete graph K N with edges colored arbitrarily by red or blue, we consider the proposition of the subgraph of the red graph or blue graph induced by t... In this paper, we use a combinatorial analysis method. In the complete graph K N with edges colored arbitrarily by red or blue, we consider the proposition of the subgraph of the red graph or blue graph induced by the neighborhood of some vertex in V(K N). Inspired by the main results of Jayawardene and Rousseau (Ars Combinatoria, 2000, 163-173), we determine the Ramsey numbers of r(K 1, 4, G), where G is the three-partite graph of order six without isolate vertex. 展开更多
关键词 Ramsey number the graph of order six three-partite graph
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Generalizations of Euler Numbers and Euler Numbers of Higher Order 被引量:5
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作者 LUOQiu-ming QIFeng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期54-58,共5页
The purpose of this paper is to define the generalized Euler numbers and the generalized Euler numbers of higher order, their recursion formula and some properties were established, accordingly Euler numbers and Euler... The purpose of this paper is to define the generalized Euler numbers and the generalized Euler numbers of higher order, their recursion formula and some properties were established, accordingly Euler numbers and Euler numbers of higher order were extended. 展开更多
关键词 Euler numbers higher order Euler numbers generalized Euler numbers generalized higher order Euler numbers recursion formula
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A METHOD OF SOLVING THE FUZZY FINITE ELEMENT EQUATIONS IN MONOSOURCE FUZZY NUMBERS 被引量:4
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作者 刘长虹 陈虬 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第11期1272-1276,共5页
For same cases the rules of monosource fuzzy numbers con be used into the solution of fuzzy stochastic finite element equations in engineering. This method can reduce the computing quantity of the solution. It can be ... For same cases the rules of monosource fuzzy numbers con be used into the solution of fuzzy stochastic finite element equations in engineering. This method can reduce the computing quantity of the solution. It can be proved that the amount of the solution is nearly as much as that with the general stochastic finite element method (SFEM). In addition, a new method to appreciate the structural fuzzy failure probability is presented for the needs of the modem engineering design. 展开更多
关键词 fuzzy number fuzzy stochastic finite element method (FSFEM) Edgeworth series
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A RECOGNITION OF SIMPLE GROUPS PSL(3,q) BY THEIR ELEMENT ORDERS 被引量:2
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作者 M.R.Darafsheh A.R.Moghaddamfar A.R.Zokayi 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期45-51,共7页
For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G i... For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G is called k-recognizable if h(πe(G)) = k <∞, otherwise G is called non-recognizable. Also a 1-recognizable group is called a recognizable (or characterizable) group. In this paper the authors show that the simple groups PSL(3,q), where 3 < q≡±2 (mod 5) and (6, (q-1)/2) = 1, are recognizable. 展开更多
关键词 Element order prime graph projective special linear group
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Error Analysis of A New Higher Order Boundary Element Method for A Uniform Flow Passing Cylinders
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作者 SUN Shi-yan CUI Jie BAO Chao-ming 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期369-377,共9页
A higher order boundary element method(HOBEM)is presented for inviscid flow passing cylinders in bounded or unbounded domain.The traditional boundary integral equation is established with respect to the velocity poten... A higher order boundary element method(HOBEM)is presented for inviscid flow passing cylinders in bounded or unbounded domain.The traditional boundary integral equation is established with respect to the velocity potential and its normal derivative.In present work,a new integral equation is derived for the tangential velocity.The boundary is discretized into higher order elements to ensure the continuity of slope at the element nodes.The velocity potential is also expanded with higher order shape functions,in which the unknown coefficients involve the tangential velocity.The expansion then ensures the continuities of the velocity and the slope of the boundary at element nodes.Through extensive comparison of the results for the analytical solution of cylinders,it is shown that the present HOBEM is much more accurate than the conventional BEM. 展开更多
关键词 higher order boundary element method(HOBEM) error analysis integral equations for potential and velocity cylinders
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The Counting Problem of an Order N-group of Set 被引量:1
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作者 WANGJing-zhou ZHANGHai-mo 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期283-285,共3页
In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3)... In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3) ∩ni=1A 1{b 1,b 2,…,b k}; (4) A i≠Φ (i=1,2,…,k). We solve these problems by element analytical meth od. 展开更多
关键词 an order n-group of set element analytical meth od COUNTING
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A new higher-order shear deformation theory and refined beam element of composite laminates 被引量:3
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作者 WanjiChen ZhenWu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第1期65-69,共5页
A new higher-order shear deformation theory based on global-local superposition technique is developed. The theory satisfies the free surface conditions and the geometric and stress continuity conditions at interfaces... A new higher-order shear deformation theory based on global-local superposition technique is developed. The theory satisfies the free surface conditions and the geometric and stress continuity conditions at interfaces. The global displacement components are of the Reddy theory and local components are of the internal first to third-order terms in each layer. A two-node beam element based on this theory is proposed. The solutions are compared with 3D-elasticity solutions. Numerical results show that present beam element has higher computational efficiency and higher accuracy. 展开更多
关键词 Laminated composite beam Higher-order shear deformation theory Refined beam element
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The Distribution of Prime Numbers and Finding the Factor of Composite Numbers without Searching
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作者 Dagnachew Jenber 《Advances in Pure Mathematics》 2015年第6期338-352,共15页
In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last o... In this paper, there are 5 sections of tables represented by 5 linear sequence functions. There are two one-variable sequence functions that they are able to represent all prime numbers. The first one helps the last one to produce another three two-variable linear sequence functions. With the help of these three two-variable sequence functions, the last one, one-variable sequence function, is able to set apart all prime numbers from composite numbers. The formula shows that there are infinitely many prime numbers by applying limit to infinity. The three two-variable sequence functions help us to find the factor of all composite numbers. 展开更多
关键词 the nth SEQUENCE of an ARITHMETIC SEQUENCE number of elements of the Set SEQUENCE FUNCTIONS
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Characterization of Type p Banach Spaces by the Weak Law of Large Numbers
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作者 Gan Shi-xin School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2002年第1期14-19,共6页
For weighted sums of the form ?j = 1kn anj Xnj\sum {_{j = 1}^{k_n } } a_{nj} X_{nj} where {a nj , 1 ?j?k n ↑∞,n?1} is a real constant array and {X aj , 1≤j≤k n, n≥1} is a rowwise independent, zero mean, rando... For weighted sums of the form ?j = 1kn anj Xnj\sum {_{j = 1}^{k_n } } a_{nj} X_{nj} where {a nj , 1 ?j?k n ↑∞,n?1} is a real constant array and {X aj , 1≤j≤k n, n≥1} is a rowwise independent, zero mean, random element array in a real separable Banach space of typep, we establishL r convergence theorem and a general weak law of large numbers respectively, conversely, we characterize Banach spaces of typep in terms of convergence inr-th mean and probability for such weighted sums. 展开更多
关键词 Key words Banach space of typep array of random elements weighted sums weak law of large numbers {a nj } uniform integrability L r convergence convergence in probability
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The Formula of General Term of the Sum of Equal Powers of Natural Numbers
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作者 高英敏 杨志忠 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期21-27, ,共7页
The formula of general term of the sum of equal powers of natural numbers.
关键词 the sum of equal powers of natural numbers Abel change sequence of number of arithmetic of higher order
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Theoretical calculation of tidal Love numbers of the Moon with a new spectral element method
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作者 BinBin Liao XiaoDong Chen +2 位作者 JianQiao Xu JiangCun Zhou HePing Sun 《Earth and Planetary Physics》 EI CSCD 2022年第3期241-247,共7页
The tidal Love numbers of the Moon are a set of nondimensional parameters that describe the deformation responses of the Moon to the tidal forces of external celestial bodies.They play an important role in the theoret... The tidal Love numbers of the Moon are a set of nondimensional parameters that describe the deformation responses of the Moon to the tidal forces of external celestial bodies.They play an important role in the theoretical calculation of the Moon’s tidal deformation and the inversion of its internal structure.In this study,we introduce the basic theory for the theoretical calculation of the tidal Love numbers and propose a new method of solving the tidal Love numbers:the spectral element method.Moreover,we explain the mathematical theory and advantages of this method.On the basis of this new method,using 10 published lunar internal structure reference models,the lunar surface and lunar internal tidal Love numbers were calculated,and the influence of different lunar models on the calculated Love numbers was analyzed.Results of the calculation showed that the difference in the second-degree lunar surface Love numbers among different lunar models was within 8.5%,the influence on the maximum vertical displacement on the lunar surface could reach±8.5 mm,and the influence on the maximum gravity change could reach±6μGal.Regarding the influence on the Love numbers inside the Moon,different lunar models had a greater impact on the Love numbers h_(2) and l_(2) than on k_(2) in the lower lunar mantle and core. 展开更多
关键词 lunar tidal Love numbers spectral element method solid lunar tides lunar internal structure reference models lunar tidal deformation theory
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A New Fourth Order Difference Approximation for the Solution of Three-dimensional Non-linear Biharmonic Equations Using Coupled Approach
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作者 Ranjan Kumar Mohanty Mahinder Kumar Jain Biranchi Narayan Mishra 《American Journal of Computational Mathematics》 2011年第4期318-327,共10页
This paper deals with a new higher order compact difference scheme, which is, O(h4) using coupled approach on the 19-point 3D stencil for the solution of three dimensional nonlinear biharmonic equations. At each inter... This paper deals with a new higher order compact difference scheme, which is, O(h4) using coupled approach on the 19-point 3D stencil for the solution of three dimensional nonlinear biharmonic equations. At each internal grid point, the solution u(x,y,z) and its Laplacian Δ4u are obtained. The resulting stencil algo-rithm is presented and hence this new algorithm can be easily incorporated to solve many problems. The present discretization allows us to use the Dirichlet boundary conditions only and there is no need to discretize the derivative boundary conditions near the boundary. We also show that special treatment is required to handle the boundary conditions. Convergence analysis for a model problem is briefly discussed. The method is tested on three problems and compares very favourably with the corresponding second order approximation which we also discuss using coupled approach. 展开更多
关键词 THREE-DIMENSIONAL NON-LINEAR BIHARMONIC Equation Finite Differences Fourth order Accuracy Compact Discretization Block-Block-Tridiagonal Tangential Derivatives Laplacian Stream Function REYNOLDS number
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Unified analysis for stabilized methods of low-order mixed finite elements for stationary Navier-Stokes equations 被引量:2
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作者 陈刚 冯民富 何银年 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第8期953-970,共18页
A unified analysis is presented for the stabilized methods including the pres- sure projection method and the pressure gradient local projection method of conforming and nonconforming low-order mixed finite elements f... A unified analysis is presented for the stabilized methods including the pres- sure projection method and the pressure gradient local projection method of conforming and nonconforming low-order mixed finite elements for the stationary Navier-Stokes equa- tions. The existence and uniqueness of the solution and the optimal error estimates are proved. 展开更多
关键词 Navier-Stokes equation Ladyzhenskaya-Babu^ka-Brezzi (LBB) condition low-order finite element pressure projection method pressure gradient local projectionmethod
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Oscillation behaviour in the photon-number distribution of squeezed coherent states
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作者 王帅 张晓燕 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期254-259,共6页
From the normally ordered form of the density operator of a squeezed coherent state(SCS),we directly derive the compact expression of the SCS's photon-number distribution(PND).Besides the known oscillation charac... From the normally ordered form of the density operator of a squeezed coherent state(SCS),we directly derive the compact expression of the SCS's photon-number distribution(PND).Besides the known oscillation characteristics,we find that the PND is a periodic function with a period of π and extremely sensitive to phase.If the squeezing is strong enough,and the compound phase which is relevant to the complex squeezing and displacement parameters are assigned appropriate values,different oscillation behaviours in PND for even and odd photon numbers appear,respectively. 展开更多
关键词 photon-number distribution squeezed coherent states normal ordering
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Evaluate All the Order of Every Element in the Higher Order of Group for Addition and Multiplication Composition
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作者 Md. Abdul Mannan Nazmun Nahar +3 位作者 Halima Akter Momtaz Begum Md. Amanat Ullah Shabnam Mustari 《International Journal of Modern Nonlinear Theory and Application》 2022年第2期11-30,共20页
This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of el... This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of element of a group in real numbers. Here we discuss the higher order of groups in different types of order which will give us practical knowledge to see the applications of the addition and multiplication composition. If G is a finite group, n is a positive integer and a &isins;G, then the order of the products na. When G is a finite group, every element must have finite order. However, the converse is false: there are infinite groups where each element has finite order. For example, in the group of all roots of unity in C<sup>×</sup> each element has finite order. Finally, we find out the order of every element of a group in different types of higher order of group. 展开更多
关键词 order of Element of a Group Addition Composition Multiplication Composition Modulo
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Electromagnetic Interpretation of Fractional-Order Elements
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作者 Guishu Liang Jiawei Hao Dongqing Shan 《Journal of Modern Physics》 2017年第14期2209-2218,共10页
Fractional circuits have attracted extensive attention of scholars and researchers for their superior performance and potential applications. Recently, the fundamentals of the conventional circuit theory were extended... Fractional circuits have attracted extensive attention of scholars and researchers for their superior performance and potential applications. Recently, the fundamentals of the conventional circuit theory were extended to include the new generalized elements and fractional-order elements. As is known to all, circuit theory is a limiting special case of electromagnetic field theory and the characterization of classical circuit elements can be given an elegant electromagnetic interpretation. In this paper, considering fractional-order time derivatives, an electromagnetic field interpretation of fractional-order elements: fractional-order inductor, fractional-order capacitor and fractional-order mutual inductor is presented, in terms of a quasi-static expansion of the fractional Maxwell’s equations. It shows that fractional-order elements can also be interpreted as a fractional electromagnetic system. As the element order equals to 1, the interpretation of fractional-order elements matches that of the classical circuit elements: L, C, and mutual inductor, respectively. 展开更多
关键词 FRACTIONAL CIRCUITS FRACTIONAL-order elements Maxwell’s EQUATIONS ELECTROMAGNETIC Field
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Finite Element Approach for the Solution of First-Order Differential Equations
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作者 André Schmidt Horst R. Beyer +1 位作者 Matthias Hinze Evangelos N. Vandoros 《Journal of Applied Mathematics and Physics》 2020年第10期2072-2090,共19页
The finite element method has established itself as an efficient numerical procedure for the solution of arbitrary-shaped field problems in space. Basically, the finite element method transforms the underlying differe... The finite element method has established itself as an efficient numerical procedure for the solution of arbitrary-shaped field problems in space. Basically, the finite element method transforms the underlying differential equation into a system of algebraic equations by application of the method of weighted residuals in conjunction with a finite element ansatz. However, this procedure is restricted to even-ordered differential equations and leads to symmetric system matrices as a key property of the finite element method. This paper aims in a generalization of the finite element method towards the solution of first-order differential equations. This is achieved by an approach which replaces the first-order derivative by fractional powers of operators making use of the square root of a Sturm-Liouville operator. The resulting procedure incorporates a finite element formulation and leads to a symmetric but dense system matrix. Finally, the scheme is applied to the barometric equation where the results are compared with the analytical solution and other numerical approaches. It turns out that the resulting numerical scheme shows excellent convergence properties. 展开更多
关键词 Finite Element Method First-order Differential Equations Fractional Powers of Operators
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The Analysis of Strategic Driving Factors of Logistics Cost Based on Fuzzy Multiple-attribute Lattice-order Decision-making Method
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《成都信息工程学院学报》 2012年第5期511-515,共5页
关键词 最优化 数学 理论 函数
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Oscillation behaviour in the photon-number distribution of squeezed coherent states
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作者 王帅 张晓燕 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期258-263,共6页
From the normally ordered form of the density operator of a squeezed coherent state(SCS),we directly derive the compact expression of the SCS’s photon-number distribution(PND).Besides the known oscillation characteri... From the normally ordered form of the density operator of a squeezed coherent state(SCS),we directly derive the compact expression of the SCS’s photon-number distribution(PND).Besides the known oscillation characteristics,we find that the PND is a periodic function with a period of π and extremely sensitive to phase.If the squeezing is strong enough,and the compound phase which is relevant to the complex squeezing and displacement parameters are assigned appropriate values,different oscillation behaviours in PND for even and odd photon numbers appear,respectively. 展开更多
关键词 photon-number distribution squeezed coherent states normal ordering
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