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LEIBNIZ′FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF DIFFERENTIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN′S FUNCTION 被引量:1
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作者 许跃生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1359-1364,共6页
In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green fun... In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green function about the operators is also given. 展开更多
关键词 LEIBNIZ S FUNCTION FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF differentIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN
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Investigation of Gate Defects in Ultrathin MOS Structures Using DTRS Technique
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作者 霍宗亮 杨国勇 +2 位作者 许铭真 谭长华 段小蓉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第11期1146-1153,共8页
s:A detailed description of relaxation spectroscopy technique under direct tunneling stress is given.A double peak phenomena by applied relaxation spectroscopy on ultra thin (<3nm) gate oxide is found.It suggests ... s:A detailed description of relaxation spectroscopy technique under direct tunneling stress is given.A double peak phenomena by applied relaxation spectroscopy on ultra thin (<3nm) gate oxide is found.It suggests that two kinds of traps exist in the degradation of gate oxide.It is also observed that both the trap density and the generation/capture cross section of oxide trap and interface trap are smaller in ultra thin gate oxide (<3nm) under DT stress than those in the thicker oxide (>4nm) under FN stress,and the centroid of oxide trap is closer to anode interface than in the center of oxide. 展开更多
关键词 TUNNELING metal oxide semiconductor device proportional difference operator
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ENTIRE FUNCTIONS SHARING ONE SMALL FUNCTION CM WITH THEIR SHIFTS AND DIFFERENCE OPERATORS 被引量:3
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作者 崔宁 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期786-798,共13页
In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of ... In this article, we mainly devote to proving uniqueness results for entire functionssharing one small function CM with their shift and difference operator simultaneously. Letf(z) be a nonconstant entire function of finite order, c be a nonzero finite complex constant, and n be a positive integer. If f(z), f(z+c), and △n cf(z) share 0 CM, then f(z+c)≡Af(z), where A(≠0) is a complex constant. Moreover, let a(z), b(z)( O) ∈ S(f) be periodic entire functions with period c and if f(z) - a(z), f(z + c) - a(z), △cn f(z) - b(z) share 0 CM, then f(z + c) ≡ f(z). 展开更多
关键词 Entire function SHIFTS difference operators shared values
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Graph Laplacian Matrix Learning from Smooth Time-Vertex Signal 被引量:1
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作者 Ran Li Junyi Wang +2 位作者 Wenjun Xu Jiming Lin Hongbing Qiu 《China Communications》 SCIE CSCD 2021年第3期187-204,共18页
In this paper,we focus on inferring graph Laplacian matrix from the spatiotemporal signal which is defined as“time-vertex signal”.To realize this,we first represent the signals on a joint graph which is the Cartesia... In this paper,we focus on inferring graph Laplacian matrix from the spatiotemporal signal which is defined as“time-vertex signal”.To realize this,we first represent the signals on a joint graph which is the Cartesian product graph of the time-and vertex-graphs.By assuming the signals follow a Gaussian prior distribution on the joint graph,a meaningful representation that promotes the smoothness property of the joint graph signal is derived.Furthermore,by decoupling the joint graph,the graph learning framework is formulated as a joint optimization problem which includes signal denoising,timeand vertex-graphs learning together.Specifically,two algorithms are proposed to solve the optimization problem,where the discrete second-order difference operator with reversed sign(DSODO)in the time domain is used as the time-graph Laplacian operator to recover the signal and infer a vertex-graph in the first algorithm,and the time-graph,as well as the vertex-graph,is estimated by the other algorithm.Experiments on both synthetic and real-world datasets demonstrate that the proposed algorithms can effectively infer meaningful time-and vertex-graphs from noisy and incomplete data. 展开更多
关键词 Cartesian product graph discrete secondorder difference operator Gaussian prior distribution graph Laplacian matrix learning spatiotemporal smoothness time-vertex signal
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A NOTE ON VALUE DISTRIBUTION OF DIFFERENCE POLYNOMIALS OF MEROMORPHIC FUNCTIONS 被引量:2
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作者 姚丽萍 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1826-1834,共9页
In this paper, we investigate the value distribution of the difference counterpart △f(z)- af(z)^n of f′(z)- af(z)^n and obtain an almost direct difference analogue of result of Hayman.
关键词 shift difference operator order
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Finite-difference time-domain studies of low-frequency stop band in superconductor-dielectric superlattice 被引量:1
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作者 王身云 刘少斌 Le-Wei Joshua Li 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期374-378,共5页
The transmission coefficients of electromagnetic (EM) waves due to a superconductor-dielectric superlattice are numerically calculated. Shift operator finite difference time domain (SO-FDTD) method is used in the ... The transmission coefficients of electromagnetic (EM) waves due to a superconductor-dielectric superlattice are numerically calculated. Shift operator finite difference time domain (SO-FDTD) method is used in the analysis. By using the SO-FDTD method, the transmission spectrum is obtained and its characteristics are investigated for different thicknesses of superconductor layers and dielectric layers, from which a stop band starting from zero frequency can be apparently observed. The relation between this low-frequency stop band and relative temperature, and also the London penetration depth at a superconductor temperature of zero degree are discussed, separately. The low-frequency stop band properties of superconductor-dielectric superlattice thus are well disclosed. 展开更多
关键词 shift operator finite difference time domain method SUPERCONDUCTOR superconductor- dielectric superlattice high-pass filter
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Mutual transformations between the P–Q, Q–P, and generalized Weyl ordering of operators
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作者 徐兴磊 李洪奇 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期119-122,共4页
Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respec... Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respectively, we find the mutual transformations between 6 (p - P) (q - Q), (q - Q) 3 (p - P), and (p, q), which are, respectively, the integration kernels of the P-Q, Q-P, and generalized Weyl quantization schemes. The mutual transformations provide us with a new approach to deriving the Wigner function of quantum states. The - and - ordered forms of (p, q) are also derived, which helps us to put the operators into their - and - ordering, respectively. 展开更多
关键词 generalized Wigner operator generalized Weyl quantization scheme different operator orderingrules mutual transformation
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CHARACTERIZATIONS OF PRINCIPAL SHIFT-INVARIANT SPACES
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作者 Wu ZhengchangDept. of Math.,Zhejiang Univ.,Hangzhou 310027,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期291-300,共10页
Shifts-invariant spaces in L 1(R) are investigated. First,based on a study of the system of linearly difference operators,the method of constructing generators with linearly independent shifts is provided. Then the c... Shifts-invariant spaces in L 1(R) are investigated. First,based on a study of the system of linearly difference operators,the method of constructing generators with linearly independent shifts is provided. Then the characterizations of the closed shift-invariant subspaces in L 1(R) are given in terms of such generators and the local basis of shift-invariant subspaces. 展开更多
关键词 shift-invariant spaces difference operators linearly independent shifts generator.
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On Some Class of n-Normed Generalized Difference Sequences Related to l_p-Space
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作者 Binod Chandra Tripathy Inder Kumar Rana Stuti Borgohain 《Analysis in Theory and Applications》 2014年第2期214-223,共10页
In this paper, we introduce the class of n-normed generalized difference sequences related to lp-space. Some properties of this sequence space like solidness, symmetricity, convergence-free etc. are studied. We obtain... In this paper, we introduce the class of n-normed generalized difference sequences related to lp-space. Some properties of this sequence space like solidness, symmetricity, convergence-free etc. are studied. We obtain some inclusion relations involving this sequence space. 展开更多
关键词 Generalized difference operator n-norm n-Banach space symmetricity solidness convergence free completeness.
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An Optimal Spatial Finite-Difference Operator which ReducesTruncation Error to a Minimum
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作者 王 元 伍荣生 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第3期468-486,共19页
Highly accurate spatial discretization is essentially required to perform numerical climate and weather prediction. The difference between the differential and the finite-difference operator is however a primitive err... Highly accurate spatial discretization is essentially required to perform numerical climate and weather prediction. The difference between the differential and the finite-difference operator is however a primitive error source in the numerics. This paper presents an optimization of centered finite-difference operator based on the principle of constrained cost function, which can reduce the truncation error to minimum. In the optimization point of view, such optimal operator is in fact an attempt to minimize spatial truncation er-rors in atmospheric modeling, in a simple way and indeed a quite innovative way to implement Variational Continuous Assimilation (VCA) technique. Furthermore, the optimizing difference operator is consciously designed to be meshing-independent, so that it can be used for most Arakawa-mesh configurations, such as un-staggered (Arakawa-A) or com-monly staggered (Arakawa-B, Arakawa-C, Arakawa-D) mesh. But for the calibration purpose, the pro-posed operator is implemented on an un-staggered mesh in which the truncation oscillation is mostly ex-cited, and it thus makes a severe and indeed a benchmark test for the proposed optimal scheme. Both theo-retical investigation and practical modeling indicate that the aforementioned numerical noise can be significantly eliminated. 展开更多
关键词 Finite—difference operator Truncation error OPTIMIZATION
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NOTES ON THE SPECTRAL PROPERTIES OF THE WEIGHTED MEAN DIFFERENCE OPERATOR G(u,v;?) OVER THE SEQUENCE SPACE ?_1
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作者 Vatan KARAKAYA Ezgi ERDOGAN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期477-486,共10页
In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1.... In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1. The product operator G (u, v; △) over l1 is defined by (G(u,v;△)x)k=^k∑i=0ukvi(xi- xi-1) with xk = 0 for all k 〈 0, where x = (xk)∈e1,and u and v axe either constant or strictly decreasing sequences of positive real numbers satisfying certain conditions. In this article we give some improvements of the computation of the spectrum of the operator G (u, v; △) on the sequence space gl. 展开更多
关键词 Spectrum of an operator weighted mean difference operator sequence space
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Separation of Waves by Interpolation Method
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作者 孙鹤泉 王永学 《海洋工程:英文版》 2003年第1期123-132,共10页
The separation of waves by an interpolation method is presented in detail. The composite wave sequences measured with two wave gauges in the wave flume are separated very quickly into two series of incident and reflec... The separation of waves by an interpolation method is presented in detail. The composite wave sequences measured with two wave gauges in the wave flume are separated very quickly into two series of incident and reflected waves in time domain via the simple interpolation and difference operations. Then, the reflection coefficient can be estimated easily and accurately without calculation of wave heights and phases. The intial phase of reflection can also be detected easily for improvement of the accuracy of calculation. The present method is applicable to both regular and irregular trains of waves based on the linear wave theory which are proved to be accurate through numerical sample tests. Physical experiments are conducted and compared with Goda′s method and analytical method with satisfactory results. Furthermore, the present method can be used for the absorbing wave maker to extract reflected waves in real time. 展开更多
关键词 separation of waves reflection coefficient INTERPOLATION difference operation
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On a Difference Matrix and Its Properties
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作者 P.Baliarsingh L.Nayak 《Analysis in Theory and Applications》 CSCD 2017年第4期375-383,共9页
In the present paper, a new difference matrix via difference operator D is introduced. Let x = (xk) be a sequence of real numbers, then the difference operatorD is defined by D(x)n =∑kn=0(-1)k(n-kn)xk,where ... In the present paper, a new difference matrix via difference operator D is introduced. Let x = (xk) be a sequence of real numbers, then the difference operatorD is defined by D(x)n =∑kn=0(-1)k(n-kn)xk,where n = 0,1,2,3,.... Several interestingproperties of the new operator D are discussed. 展开更多
关键词 Difference operators △α B(r s) B(r s t u) D Cesaro operator C(1 1).
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2-Harmonic Curves Isometrially Immersed in a Surface
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作者 格桑尼玛 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第3期103-107,共5页
In this paper,the author proves the necessary and sufficient condition for the existence of 2-harmonically and isometrically immersed curves in a 2-dimensinonal surface N∪→IE^3.
关键词 Rieman manifold comact differental operator
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ELEMENT FUNCTIONS OF DISCRETE OPERATOR DIFFERENCE METHOD
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作者 田中旭 唐立民 刘正兴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期619-626,共8页
The discrete scheme called discrete operator difference for differential equations was given. Several difference elements for plate bending problems and plane problems were given. By investigating these elements, the ... The discrete scheme called discrete operator difference for differential equations was given. Several difference elements for plate bending problems and plane problems were given. By investigating these elements, the ability of the discrete forms expressing to the element functions was talked about. In discrete operator difference method, the displacements of the elements can be reproduced exactly in the discrete forms whether the displacements are conforming or not. According to this point, discrete operator difference method is a method with good performance. 展开更多
关键词 discrete operator difference method element function reproduce exactly
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Determination of Threshold Voltage and Mobility ofMOSFET by Proportional Difference Operator
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作者 王金延 许铭真 谭长华 《Journal of Semiconductors》 CSCD 北大核心 2000年第12期1198-1202,共5页
Proportional Difference Operator (PDO) method is proposed for the first time to determine the key parameters of a MOSFET, including the threshold voltage and ca rrier mobility.This method is applied to the transfer ch... Proportional Difference Operator (PDO) method is proposed for the first time to determine the key parameters of a MOSFET, including the threshold voltage and ca rrier mobility.This method is applied to the transfer characteristic of a MOSFET first, and then the effect of gate voltage on carrier mobility is considered. The dependence of carrier mobility on the gate voltage is obtained. 展开更多
关键词 proportional difference operator transfer char acteristic MOSFET
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Uniqueness of Entire Functions Concerning Differences
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作者 QIU Shi-lin LIU Dan 《Chinese Quarterly Journal of Mathematics》 2021年第4期376-389,共14页
In this paper,we study the uniqueness of entire functions and prove the following theorem.Let f be a transcendental entire function of finite order.Then there exists at most one positive integer k,such that f(z)△^(k)... In this paper,we study the uniqueness of entire functions and prove the following theorem.Let f be a transcendental entire function of finite order.Then there exists at most one positive integer k,such that f(z)△^(k)_(c)f(z)-R(z)has finitely many zeros,where R(z)is a non-vanishing rational function and c is a nonzero complex number.Our result is an improvement of the theorem given by Andasmas and Latreuch[1]. 展开更多
关键词 Nevanlinna theory UNIQUENESS Entire functions Difference operators
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A Numerical Algorithm for the Caputo Tempered Fractional Advection-Diffusion Equation
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作者 Wenhui Guan Xuenian Cao 《Communications on Applied Mathematics and Computation》 2021年第1期41-59,共19页
By transforming the Caputo tempered fractional advection-diffusion equation into the Riemann–Liouville tempered fractional advection-diffusion equation,and then using the fractional-compact Grünwald–Letnikov te... By transforming the Caputo tempered fractional advection-diffusion equation into the Riemann–Liouville tempered fractional advection-diffusion equation,and then using the fractional-compact Grünwald–Letnikov tempered difference operator to approximate the Riemann–Liouville tempered fractional partial derivative,the fractional central difference operator to discritize the space Riesz fractional partial derivative,and the classical central difference formula to discretize the advection term,a numerical algorithm is constructed for solving the Caputo tempered fractional advection-diffusion equation.The stability and the convergence analysis of the numerical method are given.Numerical experiments show that the numerical method is effective. 展开更多
关键词 Caputo tempered fractional advection-diffusion equation Fractional-compact Grünwald–Letnikov tempered Fractional central difference operator Stability Convergence
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Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order
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作者 Hui LI Ming Liang FANG Xiao YAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第2期511-527,共17页
We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new method.It is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ countin... We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new method.It is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of Jank-Mues-Volkmann.Our method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding vectors.This makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the functions.Furthermore,the idea in this paper can also be applied to the case for several variables. 展开更多
关键词 UNIQUENESS meromorphic functions difference operators infinite order
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Meromorphic Functions Sharing Two Values
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作者 ZHAO Ying HUANG Zhigang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第1期7-12,共6页
Let f and g be two nonconstant meromorphic functions,and n be a positive integer.If f^(n)(z)and g^(n)(z)share 1 CM(counting multiplicities),f(z)and g(z)share∞IM(ignoring multiplicities),and N(r,1f)+N(r,1g)=S(r,f)+S(r... Let f and g be two nonconstant meromorphic functions,and n be a positive integer.If f^(n)(z)and g^(n)(z)share 1 CM(counting multiplicities),f(z)and g(z)share∞IM(ignoring multiplicities),and N(r,1f)+N(r,1g)=S(r,f)+S(r,g),then either f(z)≡tg(z)or f(z)g(z)≡t,where t^(n)=1.As an application,shared values problems of a meromorphic function related to its shifts and difference operators are also investigated. 展开更多
关键词 meromorphic function shared values difference operator SHIFT
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