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DERIVATION OF SOME SPECIAL STRESS FUNCTION FROM BELTRAMI-SCHAEFER STRESS FUNCTION
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作者 王敏中 王鲁男 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第7期665-673,共9页
Using liellrami-Schaefer stress funtion in the theory of elasticity in this paper, we derive the stress functions of torsion, plane problem, axisymmetric deformation in solid of revolution and torsion on solid of revo... Using liellrami-Schaefer stress funtion in the theory of elasticity in this paper, we derive the stress functions of torsion, plane problem, axisymmetric deformation in solid of revolution and torsion on solid of revolution. 展开更多
关键词 derivation OF SOME SPECIAL STRESS FUNCTION FROM BELTRAMI-SCHAEFER STRESS FUNCTION
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Duality between Bessel Functions and Chebyshev Polynomials in Expansions of Functions
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2023年第8期504-536,共16页
In expansions of arbitrary functions in Bessel functions or Spherical Bessel functions, a dual partner set of polynomials play a role. For the Bessel functions, these are the Chebyshev polynomials of first kind and fo... In expansions of arbitrary functions in Bessel functions or Spherical Bessel functions, a dual partner set of polynomials play a role. For the Bessel functions, these are the Chebyshev polynomials of first kind and for the Spherical Bessel functions the Legendre polynomials. These two sets of functions appear in many formulas of the expansion and in the completeness and (bi)-orthogonality relations. The analogy to expansions of functions in Taylor series and in moment series and to expansions in Hermite functions is elaborated. Besides other special expansion, we find the expansion of Bessel functions in Spherical Bessel functions and their inversion and of Chebyshev polynomials of first kind in Legendre polynomials and their inversion. For the operators which generate the Spherical Bessel functions from a basic Spherical Bessel function, the normally ordered (or disentangled) form is found. 展开更多
关键词 Spherical Bessel Functions Chebyshev Polynomials Legendre Polynomials Hermite Polynomials Derivatives of Delta Functions Normally and Anti-Normally Ordered Operators
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Clustering for Bivariate Functional Data
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作者 Shi-yun CAO Yan-qiu ZHOU +1 位作者 Yan-ling WAN Tao ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期613-629,共17页
In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on margina... In this paper,we consider the clustering of bivariate functional data where each random surface consists of a set of curves recorded repeatedly for each subject.The k-centres surface clustering method based on marginal functional principal component analysis is proposed for the bivariate functional data,and a novel clustering criterion is presented where both the random surface and its partial derivative function in two directions are considered.In addition,we also consider two other clustering methods,k-centres surface clustering methods based on product functional principal component analysis or double functional principal component analysis.Simulation results indicate that the proposed methods have a nice performance in terms of both the correct classification rate and the adjusted rand index.The approaches are further illustrated through empirical analysis of human mortality data. 展开更多
关键词 bivariate functional data -centres surface clustering functional principal component analysis partial derivative function
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ALGEBROIDAL FUNCTION AND ITS DERIVED FUNCTION IN UNIT CIRCULAR DISC 被引量:4
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作者 霍颖莹 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期129-139,共11页
In this article,the authors define the derived function of an algeboidal function in the unit disc,prove it is an algabriodal function,and study the order of algebroidal function and that of its derived function in un... In this article,the authors define the derived function of an algeboidal function in the unit disc,prove it is an algabriodal function,and study the order of algebroidal function and that of its derived function in unit circular disc. 展开更多
关键词 Algebroidal function derived function characteristic function
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SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS 被引量:1
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作者 T.F.Xie S.P.Zhou 《Analysis in Theory and Applications》 1994年第4期100-109,共10页
This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of... This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of deereeon the nodes X_nUY_n(see the definition of the next). 展开更多
关键词 SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS APPI ZR
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ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION 被引量:1
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作者 Tingfan Xie Ziyu Wang China Institute of Metrology, China Henan University, China 《Analysis in Theory and Applications》 1994年第3期45-55,共11页
The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen-... The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen- eral. 展开更多
关键词 MATH ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION 石瓦
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HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION FUNCTIONS AND THEIR LOGICAL DERIVATIVES 被引量:1
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作者 Sha Zhen Chen Gang Zhejiang University,China 《Analysis in Theory and Applications》 1993年第4期73-88,共16页
In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their... In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their logical derivatives of order α. 展开更多
关键词 HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION FUNCTIONS AND THEIR LOGICAL DERIVATIVES der HAAR FIF
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Boundary Conditions for Sturm-Liouville Equation with Transition Regions and Barriers or Wells 被引量:1
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2021年第4期254-295,共42页
By means of expansions of rapidly in infinity decreasing functions in delta functions and their derivatives, we derive generalized boundary conditions of the Sturm-Liouville equation for transitions and barriers or we... By means of expansions of rapidly in infinity decreasing functions in delta functions and their derivatives, we derive generalized boundary conditions of the Sturm-Liouville equation for transitions and barriers or wells between two asymptotic potentials for which the solutions are supposed as known. We call such expansions “moment series” because the coefficients are determined by moments of the function. An infinite system of boundary conditions is obtained and it is shown how by truncation it can be reduced to approximations of a different order (explicitly made up to third order). Reflection and refraction problems are considered with such approximations and also discrete bound states possible in nonsymmetric and symmetric potential wells are dealt with. This is applicable for large wavelengths compared with characteristic lengths of potential changes. In Appendices we represent the corresponding foundations of Generalized functions and apply them to barriers and wells and to transition functions. The Sturm-Liouville equation is not only interesting because some important second-order differential equations can be reduced to it but also because it is easier to demonstrates some details of the derivations for this one-dimensional equation than for the full three-dimensional vectorial equations of electrodynamics of media. The article continues a paper that was made long ago. 展开更多
关键词 Schrödinger Equation Drude Approximation Transition Layer Potential Barrier Potential Well Reflection REFRACTION Moment Series Generalized Functions Delta Function and Its Derivatives Discrete or Bound Eigenstates
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Basis-free expressions for derivatives of a subclass of nonsymmetric isotropic tensor functions
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作者 王志乔 兑关锁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第9期1249-1257,共9页
The present paper generalizes the method for solving the derivatives of symmetric isotropic tensor-valued functions proposed by Dui and Chen (2004) to a subclass of nonsymmetric tensor functions satisfying the commu... The present paper generalizes the method for solving the derivatives of symmetric isotropic tensor-valued functions proposed by Dui and Chen (2004) to a subclass of nonsymmetric tensor functions satisfying the commutative condition. This subclass of tensor functions is more general than those investigated by the existing methods. In the case of three distinct eigenvalues, the commutativity makes it possible to introduce two scalar functions, which will be used to construct the general nonsymmetric tensor functions and their derivatives. In the cases of repeated eigenvalues, the results are acquired by taking limits. 展开更多
关键词 nonsymmetric tensor derivative of tensor function scalar function fourthorder tensor
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ON SIMULTANEOUS APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVE BY INVERSE PAL-TYPE INTERPOLATION POLYNOMIALS
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作者 Bao Yongguang (Hangzhou University, China) 《Analysis in Theory and Applications》 1995年第4期15-23,共9页
Let ξn-1<ξn-2 <ξn-2 <… < ξ1 be the zeros of the the (n -1)-th Legendre polynomial Pn-1(x) and - 1 = xn < xn-1 <… < x1 = 1 the zeros of the polynomial W n(x) =- n(n - 1) Pn-1(t)dt = (1 -x2)P&... Let ξn-1<ξn-2 <ξn-2 <… < ξ1 be the zeros of the the (n -1)-th Legendre polynomial Pn-1(x) and - 1 = xn < xn-1 <… < x1 = 1 the zeros of the polynomial W n(x) =- n(n - 1) Pn-1(t)dt = (1 -x2)P'n-1(x). By the theory of the inverse Pal-Type interpolation, for a function f(x) ∈ C[-1 1], there exists a unique polynomial Rn(x) of degree 2n - 2 (if n is even) satisfying conditions Rn(f,ξk) = f(∈ek)(1≤ k≤ n - 1) ;R'n(f,xk) = f'(xk)(1≤ k≤ n). This paper discusses the simultaneous approximation to a differentiable function f by inverse Pal-Type interpolation polynomial {Rn(f,x)} (n is even) and the main result of this paper is that if f ∈ C'[1,1], r≥2, n≥ + 2> and n is even thenholds uniformly for all x ∈ [- 1,1], where h(x) = 1 + 展开更多
关键词 MATH In ON SIMULTANEOUS APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVE BY INVERSE PAL-TYPE INTERPOLATION POLYNOMIALS PAL ITS
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A NOTE ON DERIVATIVES OF FUNCTION AND THEIR FOURIER TRANSFORMS IN L_2
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作者 周晓钟 刘兴权 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第1期53-61,共9页
The purpose of this article is to indicate the shortcomings of a few theorems of[1]. Moreover, some interesting results are detluced.
关键词 exp A NOTE ON DERIVATIVES OF FUNCTION AND THEIR FOURIER TRANSFORMS IN L2
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ON APPROXIMATION OF A FUNCTION AND ITS DERIVATIVES BY A POLYNOMIAL AND ITS DERIVATIVES
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作者 T.Kilgore J.Szabados 《Analysis in Theory and Applications》 1994年第3期93-103,共11页
Let g∈C^q[-1, 1] be such that g^((k))(±1)=0 for k=0,…,q. Let P_n be an algebraic polynomial of degree at most n, such that P_n^((k))(±1)=0 for k=0,…,[_2~ (q+1)]. Then P_n and its derivatives P_n^((k)) fo... Let g∈C^q[-1, 1] be such that g^((k))(±1)=0 for k=0,…,q. Let P_n be an algebraic polynomial of degree at most n, such that P_n^((k))(±1)=0 for k=0,…,[_2~ (q+1)]. Then P_n and its derivatives P_n^((k)) for k≤q well approximate g and its respective derivatives, provided only that P_n well approxi- mates g itself in the weighted norm ‖g(x)-P_n(x) (1-x^2)^(1/2)~q‖ This result is easily extended to an arbitrary f∈C^q[-1, 1], by subtracting from f the polynomial of minnimal degree which interpolates f^((0))…,f^((q)) at±1. As well as providing easy criteria for judging the simultaneous approximation properties of a given Polynomial to a given function, our results further explain the similarities and differences between algebraic polynomial approximation in C^q[-1, 1] and trigonometric polynomial approximation in the space of q times differentiable 2π-periodic functions. Our proofs are elementary and basic in character, permitting the construction of actual error estimates for simultaneous approximation proedures for small values of q. 展开更多
关键词 ON APPROXIMATION OF A FUNCTION AND ITS DERIVATIVES BY A POLYNOMIAL AND ITS DERIVATIVES ITS
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Reactivity of C-10 Function in Sinenxan A and Its Derivatives
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作者 Fen Mei YAO Dong Hui WANG +2 位作者 Guang Yan HUANG Ji Yu GUO Xiao Tian LIANG(Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Modical College, Beijing 100050,China) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,0-0,共4页
The allylic nature of C-10 in sinenxan A (1) leads to facile SN1 and eliminion reactions
关键词 Reactivity of C-10 Function in Sinenxan A and Its Derivatives
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Theoretical Study on the Electronic Structures and Spectral Properties of 1,8-Naphthalimide Derivatives
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作者 王艳 高慧 +2 位作者 杨平 聂光华 宋新建 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期813-820,共8页
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-... The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(3), are investigated by density functional theory(DFT) and time-dependent density functional theory(TD-DFT) calculations in conjunction with polarizable continuum models(PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results. 展开更多
关键词 1 8-naphthalimide derivatives density functional theory frontier molecular orbital absorption spectrum emission spectrum
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APPROXIMATION OF CONVEX TYPE FUNCTION BY PARTIAL SUMS OF FOURIER SERIES
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作者 YuGuohua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期67-76,共10页
The concept of convex type function is introduced in this paper,from which a kin d of convex decomposition approach is proposed.As one of applications of this a pproach,the approximation of the convex type function b... The concept of convex type function is introduced in this paper,from which a kin d of convex decomposition approach is proposed.As one of applications of this a pproach,the approximation of the convex type function by the partial sum of its Fourier series is inves tigated.Moreover,the order of approximation is describe d with the 2th continuous modulus. 展开更多
关键词 Fourier series convex type function convex decomposition Riemann deriv ative continuous modulus approximation.
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Catalyst-Free Reaction in Water: Synthesis of Functionalized Tetrahydroindole Derivatives via Three-Component Domino Reaction
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作者 Xian Feng Jianjun Wang +3 位作者 Wei Lin Juanjuan Zhang Zhibin Huang Daqing Shi 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第9期889-896,共8页
An environmentally benign and efficient method has been developed for the synthesis of functionalized tetrahydroindole derivatives in aqueous media under catalyst-free conditions,by simply combining a phenylglyoxal mo... An environmentally benign and efficient method has been developed for the synthesis of functionalized tetrahydroindole derivatives in aqueous media under catalyst-free conditions,by simply combining a phenylglyoxal monohydrate,an enaminone,and a barbituric acid.The advantages of this method are that it is catalyst free,has an easy workup,provides good yields,and uses water as solvent,which make this procedure facile and practical. 展开更多
关键词 functionalized tetrahydroindole derivatives multi-component reaction CATALYST-FREE aqueous medium green chemistry
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Random Double Tensors Integrals
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作者 Shih Yu Chang Yimin Wei 《Annals of Applied Mathematics》 2023年第1期1-28,共28页
In this work,we try to build a theory for random double tensor integrals(DTI).We begin with the definition of DTI and discuss how randomness structure is built upon DTI.Then,the tail bound of the unitarily invariant n... In this work,we try to build a theory for random double tensor integrals(DTI).We begin with the definition of DTI and discuss how randomness structure is built upon DTI.Then,the tail bound of the unitarily invariant norm for the random DTI is established and this bound can help us to derive tail bounds of the unitarily invariant norm for various types of two tensors means,e.g.,arithmetic mean,geometric mean,harmonic mean,and general mean.By associating DTI with perturbation formula,i.e.,a formula to relate the tensor-valued function difference with respect the difference of the function input tensors,the tail bounds of the unitarily invariant norm for the Lipschitz estimate of tensor-valued function with random tensors as arguments are derived for vanilla case and quasi-commutator case,respectively.We also establish the continuity property for random DTI in the sense of convergence in the random tensor mean,and we apply this continuity property to obtain the tail bound of the unitarily invariant norm for the derivative of the tensor-valued function. 展开更多
关键词 Einstein product double tensor integrals(DTI) random DTI tail bound Lipschitz estimate convergence in the random tensor mean derivative of tensor-valued function
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New Results on Global Rank Axioms of Poset Matroids
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作者 ShuChaoLI YanQinFENG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第1期143-154,共12页
An excellent introduction to the topic of poset matroids is due to M.Barnabei, G. Nicoletti and L. Pezzoli. On the basis of their work, we have obtained the global rankaxioms for poset matroids. In this paper, we stud... An excellent introduction to the topic of poset matroids is due to M.Barnabei, G. Nicoletti and L. Pezzoli. On the basis of their work, we have obtained the global rankaxioms for poset matroids. In this paper, we study the special integral function f and obtain a newclass of poset matroids from the old ones, and then we generalize this result according to theproperties of f. Almost all of these results can be regarded as the application of global rankaxioms for poset matroids. The main results in our paper have, indeed, investigated the restrictionof the basis of the poset matroid, and we give them the corresponding geometric interpretation. 展开更多
关键词 Poset matroids Rank function Derivative function Combinatorial schemes
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Stability Analysis Using the Minimum Function Analysis Approach
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作者 李春文 杜继宏 +1 位作者 胡世文 苗原 《Tsinghua Science and Technology》 SCIE EI CAS 1997年第3期23-27,共5页
This article studies a new kind of stability judgment for dynamic systems, the definiteness Lyapunov derivative function approach based on the minimum function. The new results are described by introducing the normal ... This article studies a new kind of stability judgment for dynamic systems, the definiteness Lyapunov derivative function approach based on the minimum function. The new results are described by introducing the normal positivity. The article analyzes the relationship of a general system and a polynomial system, the judgment and measurement of positive definiteness, the polar coordinate approach, and constructing the algorithms for positive definite v·(x). Therefore, a new and systematic theory on stability judgment is clearly described. 展开更多
关键词 nonlinear STABILITY Lyapunov method definite sign derivative function approach minimum function
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Some Functions with Low Differential Uniformity
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作者 SUN Guanghong WU Chuankun 《Wuhan University Journal of Natural Sciences》 CAS 2010年第6期479-487,共9页
We study the functions with low differential uniformity,and concentrates mainly on the properties of perfect nonlinear(PN) functions,including the properties of the derivative of the components of those functions.So... We study the functions with low differential uniformity,and concentrates mainly on the properties of perfect nonlinear(PN) functions,including the properties of the derivative of the components of those functions.Some sufficient and necessary conditions have been explored to judge when a function is a PN function.These conditions may be useful in constructing new PN functions.We also construct some functions with differential 4-uniformity that have rarely been studied in the literature.Some of the constructed functions with differential 4-uniformity have high nonlinearity as well.Finally,a class of functions with differential 4-uniformity which are not extended affine equivalent to any power functions are constructed. 展开更多
关键词 differential uniformity perfect nonlinear function Carlet-Charpin-Zinoviev equivalence derivative function spectrum
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