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Spherical Functions on Fuzzy Lie Group
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作者 Murphy E. Egwe Samuel S. Sangodele 《Advances in Pure Mathematics》 2024年第4期185-195,共11页
Let G be a locally compact Lie group and its Lie algebra. We consider a fuzzy analogue of G, denoted by called a fuzzy Lie group. Spherical functions on are constructed and a version of the existence result of the Hel... Let G be a locally compact Lie group and its Lie algebra. We consider a fuzzy analogue of G, denoted by called a fuzzy Lie group. Spherical functions on are constructed and a version of the existence result of the Helgason-spherical function on G is then established on . 展开更多
关键词 Fuzzy spherical function Fuzzy Lie Group Fuzzy Manifolds
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THE SPHERICAL FUNCTIONS AND THE CENTRAL LIMIT THEOREM ON SU(2,2)/S(U(2)×U(2))
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作者 杨乔华 张钦 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期867-874,共8页
Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is g... Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is given by the hypergeometric functions of several variables. By applying this result, a central limit theorem for the space G/K is obtained. 展开更多
关键词 spherical function central limit theorem hypergeometric function
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CONSTRUCTION SPACE HARMONIC FUNCTIONS IN POLYN0MIAL FORM AND SPHERICAL FUNCTIONS BY COMPLEX-FUNCTIONAL
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作者 王其申 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第9期877-881,共5页
In this paper, applying the theory of complex-functional, not only the spaceharmonic functions in polynomial form. but aIso the spherical functions are obtained.
关键词 complex-functional harmonic functions spherical functions
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A data-adaptive network design for the regional gravity field modelling using spherical radial basis functions
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作者 Fang Zhang Huanling Liu Hanjiang Wen 《Geodesy and Geodynamics》 EI CSCD 2024年第6期627-634,共8页
A high-precision regional gravity field model is significant in various geodesy applications.In the field of modelling regional gravity fields,the spherical radial basis functions(SRBFs)approach has recently gained wi... A high-precision regional gravity field model is significant in various geodesy applications.In the field of modelling regional gravity fields,the spherical radial basis functions(SRBFs)approach has recently gained widespread attention,while the modelling precision is primarily influenced by the base function network.In this study,we propose a method for constructing a data-adaptive network of SRBFs using a modified Hierarchical Density-Based Spatial Clustering of Applications with Noise(HDBSCAN)algorithm,and the performance of the algorithm is verified by the observed gravity data in the Auvergne area.Furthermore,the turning point method is used to optimize the bandwidth of the basis function spectrum,which satisfies the demand for both high-precision gravity field and quasi-geoid modelling simultaneously.Numerical experimental results indicate that our algorithm has an accuracy of about 1.58 mGal in constructing the gravity field model and about 0.03 m in the regional quasi-geoid model.Compared to the existing methods,the number of SRBFs used for modelling has been reduced by 15.8%,and the time cost to determine the centre positions of SRBFs has been saved by 12.5%.Hence,the modified HDBSCAN algorithm presented here is a suitable design method for constructing the SRBF data adaptive network. 展开更多
关键词 Regional gravity field modelling spherical radial basis functions Poisson kernel function HDBSCAN clustering algorithm
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A function associated with spherically convex sets
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作者 GUO Qi 《苏州科技大学学报(自然科学版)》 CAS 2024年第4期76-83,共8页
This paper introduced a kind of functions associated with spherically convex sets and discussed their basic properties.Finally,it proved the spherical convexity/concavity of these functions in lower dimensional cases,... This paper introduced a kind of functions associated with spherically convex sets and discussed their basic properties.Finally,it proved the spherical convexity/concavity of these functions in lower dimensional cases,which provides useful information for the essential characteristics of these functions determining spherically convex sets.The results obtained here are helpful in setting up a systematic spherical convexity theory. 展开更多
关键词 spherical convexity spherical support function spherical radial function canonical transformation
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Generalized multiple-mode prolate spheroidal wave functions multi-carrier waveform with index modulation
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作者 XU Zhichao LU Faping +5 位作者 ZHANG Lifan YANG Dongkai LIU Chuanhui KANG Jiafang AN Qi ZHANG Zhilin 《Journal of Systems Engineering and Electronics》 2025年第2期311-322,共12页
A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The p... A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The proposed method,based on the optimized multi-index modulation, does not limit the number of signals in the first and second constellations and abandons the concept of limiting the number of signals in different constellations. It successfully increases the spectrum efficiency of the system while expanding the number of modulation symbol combinations and the index dimension of PSWFs signals. The proposed method outperforms the PSWFs multi-carrier index modulation method based on optimized multiple indexes in terms of spectrum efficiency, but at the expense of system computational complexity and bit error performance. For example, with n=10 subcarriers and a bit error rate of 1×10^(-5),spectral efficiency can be raised by roughly 12.4%. 展开更多
关键词 prolate spherical wave function(PSWF) generalized multiple-mode index modulation spectral efficiency.
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ANALYSIS OF SPHERICAL FUNCTION SPECTRAL STRUCTURE OF THE NORTHERN HEMISPHERE 500 HPA MONTHLY MEAN HEIGHT 被引量:9
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作者 王盘兴 吴洪宝 《Acta meteorologica Sinica》 SCIE 1995年第2期237-248,共12页
Study is undertaken of spherical function spectral structures of long-term mean and anomaly patterns of the Northern Hemisphere 500 hPa monthly mean geopotential height together with the seasonal and interannual varia... Study is undertaken of spherical function spectral structures of long-term mean and anomaly patterns of the Northern Hemisphere 500 hPa monthly mean geopotential height together with the seasonal and interannual variations investigated.Results show that they are marked by low dimensions and low orders,and the mean and anomaly fields can be described in terms of 20 and 50 spherical function components,respectively. 展开更多
关键词 500 hPa long-term mean pattern anomaly field spherical function spectral structure seasonal variation
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Establishment of European Regional Ionosphere Model Based on Spherical Harmonic Functions 被引量:1
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作者 Mingze Zhang 《Journal of World Architecture》 2021年第6期5-9,共5页
In order to study the temporal and spatial variation characteristics of the regional ionosphere and the modeling accuracy,the experiment is based on the spherical harmonic function model,using the GPS,Glonass,and Gali... In order to study the temporal and spatial variation characteristics of the regional ionosphere and the modeling accuracy,the experiment is based on the spherical harmonic function model,using the GPS,Glonass,and Galileo dual-frequency observation data from the 305th-334th day of the European CORS network in 2019 to establish a global ionospheric model.By analyzing and evaluating the accuracy of the global ionospheric puncture points,VTEC,and comparing code products,the test results showed that the GPS system has the most dense puncture electricity distribution,the Glonass system is the second,and the Galileo system is the weakest.The values of ionospheric VTEC calculated by GPS,Glonass and Galileo are slightly different,but in terms of trends,they are the same as those of ESA,JPL and UPC.GPS data has the highest accuracy in global ionospheric modeling.GPS,Glonass and Galileo have the same trend,but Glonass data is unstable and fluctuates greatly. 展开更多
关键词 Global ionosphere VTEC spherical harmonic function model
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Analytical Solutions to Definite Integrals for Combinations of Legendre, Bessel and Trigonometric Functions Encountered in Propagation and Scattering Problems in Spherical Coordinates
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作者 Farhad Azadi Namin 《Journal of Applied Mathematics and Physics》 2022年第9期2690-2697,共8页
Mie theory is a rigorous solution to scattering problems in spherical coordinate system. The first step in applying Mie theory is expansion of some arbitrary incident field in terms of spherical harmonics fields in te... Mie theory is a rigorous solution to scattering problems in spherical coordinate system. The first step in applying Mie theory is expansion of some arbitrary incident field in terms of spherical harmonics fields in terms of spherical which in turn requires evaluation of certain definite integrals whose integrands are products of Bessel functions, associated Legendre functions and periodic functions. Here we present analytical results for two specific integrals that are encountered in expansion of arbitrary fields in terms of summation of spherical waves. The analytical results are in terms of finite summations which include Lommel functions. A concise analytical expression is also derived for the special case of Lommel functions that arise, rendering expensive numerical integration or other iterative techniques unnecessary. 展开更多
关键词 Mie Theory Vector spherical Wave function Eigen-function Expansion spherical Harmonics Special functions
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A Review on Modeling Environmental Loading Effects and Their Contributions to Nonlinear Variations of Global Navigation Satellite System Coordinate Time Series 被引量:1
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作者 Zhao Li Weiping Jiang +3 位作者 Tonie van Dam Xiaowei Zou Qusen Chen Hua Chen 《Engineering》 2025年第4期26-37,共12页
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at... Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050. 展开更多
关键词 Environmental loading Global navigation satellite system Nonlinear variations Time series analysis Surface mass distribution Green’s function spherical harmonic function
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Differentiability of Functions on Spheres and Criterions of Convexity
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作者 CHEN Tingting GUO Qi 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2022年第4期273-280,共8页
Some basic concepts for functions defined on subsets of the unit sphere,such as the s-directional derivative,s-gradient and s-Gateaux and s-Frechet differentiability etc,are introduced and investigated.These concepts ... Some basic concepts for functions defined on subsets of the unit sphere,such as the s-directional derivative,s-gradient and s-Gateaux and s-Frechet differentiability etc,are introduced and investigated.These concepts are different from the usual ones for functions defined on subsets of Euclidean spaces,however,the results obtained here are very similar.Then,as applications,we provide some criterions of s-convexity for functions defined on unit spheres which are improvements or refinements of some known results. 展开更多
关键词 spherical convexity spherically convex function Gateaux and Frechet differentiability criterion of convexity
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ON APPROXIMATION BY SPHERICAL REPRODUCING KERNEL HILBERT SPACES
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作者 Zhixiang Chen 《Analysis in Theory and Applications》 2007年第4期325-333,共9页
The spherical approximation between two nested reproducing kernels Hilbert spaces generated from different smooth kernels is investigated. It is shown that the functions of a space can be approximated by that of the s... The spherical approximation between two nested reproducing kernels Hilbert spaces generated from different smooth kernels is investigated. It is shown that the functions of a space can be approximated by that of the subspace with better smoothness. Furthermore, the upper bound of approximation error is given. 展开更多
关键词 spherical harmonic polynomial radial basis function reproducing kernel Hilbert space error estimates
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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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Eigenfunctions for a Quantum Wire on a Single Electron at Its Surface and in the Quantum Well with Beaded Fractional Quantized States for the Fractional Charges
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作者 Saleem Iqbal Farhana Sarwar Syed Mohsin Raza 《Journal of Applied Mathematics and Physics》 2016年第2期320-327,共8页
We developed energy profiles for the fractional quantized states both on the surface of electron due to overwhelming centrifugal potentials and inside the electron at different locations of the quantum well due to ove... We developed energy profiles for the fractional quantized states both on the surface of electron due to overwhelming centrifugal potentials and inside the electron at different locations of the quantum well due to overwhelming attractive electrodynamic potentials. The charge as a physical constant and single entity is taken as density and segments on their respective sub-quanta (floats on sub quanta) and hence the fractional charge quantiz at in. There is an integrated oscillatory effect which ties all fractional quantized states both on the surface and in the interior of the volume of an electron. The eigenfunctions, i.e., the energy profiles for the electron show the shape of a string or a quantum wire in which fractional quantized states are beaded. We followed an entirely different approach and indeed thesis to reproducing the eigenfunctions for the fractional quantized states for a single electron. We produced very fascinating mathematical formulas for all such cases by using Hermite and Laguerre polynomials, spherical based and Neumann functions and indeed asymptotic behavior of Bessel and Neumann functions. Our quantization theory is dealt in the momentum space. 展开更多
关键词 Fractional Charge Quantization Fractional Fourier Transform Hermite Polynomials Sub Quanta of Electron spherical Bessel and Neumann functions Lagueree Polynomials
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Accurate estimation of Li/Ni mixing degree of lithium nickel oxide cathode materials
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作者 陈鹏浩 徐磊 +1 位作者 禹习谦 李泓 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期631-635,共5页
Li/Ni mixing negatively influences the discharge capacity of lithium nickel oxide and high-nickel ternary cathode materials.However,accurately measuring the Li/Ni mixing degree is difficult due to the preferred orient... Li/Ni mixing negatively influences the discharge capacity of lithium nickel oxide and high-nickel ternary cathode materials.However,accurately measuring the Li/Ni mixing degree is difficult due to the preferred orientation of labbased XRD measurements using Bragg–Brentano geometry.Here,we find that employing spherical harmonics in Rietveld refinement to eliminate the preferred orientation can significantly decrease the measurement error of the Li/Ni mixing ratio.The Li/Ni mixing ratio obtained from Rietveld refinement with spherical harmonics shows a strong correlation with discharge capacity,which means the electrochemical capacity of lithium nickel oxide and high-nickel ternary cathode can be estimated by the Li/Ni mixing degree.Our findings provide a simple and accurate method to estimate the Li/Ni mixing degree,which is valuable to the structural analysis and screening of the synthesis conditions of lithium nickel oxide and high-nickel ternary cathode materials. 展开更多
关键词 lithium nickel oxide high-nickel ternary cathode Li/Ni mixing spherical harmonics function discharge capacity
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ON UNIQUE CONTINUATION PROPERTIES FOR THE SUB-LAPLACIAN ON CARNOT GROUPS
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作者 钮鹏程 王家林 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1776-1784,共9页
In this article, authors begin with establishing representation formulas and properties for functions on Carnot groups. Then, some unique continuation results to solutions of sub-Laplace equations with potentials are ... In this article, authors begin with establishing representation formulas and properties for functions on Carnot groups. Then, some unique continuation results to solutions of sub-Laplace equations with potentials are proved. 展开更多
关键词 unique continuation representation formula spherical function Carnotgroup SUB-LAPLACIAN
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The Central Limit Theorem on SU(n,1)/S(U(n)×U(1))
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作者 连保胜 胡适耕 车颖涛 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期21-27,共7页
Let G = SU(n, 1), K = S(U(n) × U(1)), and for l ∈Z, let {T;},l∈Z be a one- Dimensional K-type and let Et be the line bundle over G/K associated to Tl. In this work we obtain a central limit theorem for ... Let G = SU(n, 1), K = S(U(n) × U(1)), and for l ∈Z, let {T;},l∈Z be a one- Dimensional K-type and let Et be the line bundle over G/K associated to Tl. In this work we obtain a central limit theorem for the space Et. 展开更多
关键词 central limit theorem spherical function hypergeometric function
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Analytical solution for electromagnetic scattering from a sphere of uniaxial left-handed material 被引量:7
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作者 耿友林 何赛灵 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第1期99-104,共6页
Based on the analytical solution of electromagnetic scattering by a uniaxial anisotropic sphere in the spectral domain, an analytical solution to the electromagnetic scattering by a uniaxial left-handed materials (LHM... Based on the analytical solution of electromagnetic scattering by a uniaxial anisotropic sphere in the spectral domain, an analytical solution to the electromagnetic scattering by a uniaxial left-handed materials (LHMs) sphere is obtained in terms of spherical vector wave functions in a uniaxial anisotropic LHM medium. The expression of the analytical solution contains only some one-dimensional integral which can be calculated easily. Numerical results show that Mie series of plane wave scattering by an isotropic LHM sphere is a special case of the present method. Some numerical results of electromagnetic scattering of a uniaxial anisotropic sphere by a plane wave are given. 展开更多
关键词 Electromagnetic scattering Uniaxial anisotropic LHM spherical vector wave functions Radar cross section (RCS)
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Spherical Scattered Data Quasi-interpolation by Gaussian Radial Basis Function 被引量:2
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作者 Zhixiang CHEN Feilong CAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第3期401-412,共12页
Since the spherical Gaussian radial function is strictly positive definite, the authors use the linear combinations of translations of the Gaussian kernel to interpolate the scattered data on spheres in this article. ... Since the spherical Gaussian radial function is strictly positive definite, the authors use the linear combinations of translations of the Gaussian kernel to interpolate the scattered data on spheres in this article. Seeing that target functions axe usually outside the native spaces, and that one has to solve a large scaled system of linear equations to obtain combinatorial coefficients of interpolant functions, the authors first probe into some problems about interpolation with Gaussian radial functions. Then they construct quasi- interpolation operators by Gaussian radial function, and get the degrees of approximation. Moreover, they show the error relations between quasi-interpolation and interpolation when they have the same basis functions. Finally, the authors discuss the construction and approximation of the quasi-interpolant with a local support function. 展开更多
关键词 Scattered data APPROXIMATION spherical Gaussian radial basis function Modulus of continuity
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Lipschitz-continuity of Spherically Convex Functions 被引量:1
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作者 Yin ZHANG Qi GUO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2023年第2期363-374,共12页
In this article,some basic and important properties of spherically convex functions,such as the Lipschitz-continuity,are investigated.It is shown that,under a weaker condition,every family of spherically convex functi... In this article,some basic and important properties of spherically convex functions,such as the Lipschitz-continuity,are investigated.It is shown that,under a weaker condition,every family of spherically convex functions is equi-Lipschitzian on each closed spherically convex subset contained in the relative interior of their common domain,and from which a powerful result is derived:the pointwise convergence of a sequence of spherically convex functions implies its uniform convergence on each closed spherically convex subset contained in the relative interior of their common domain. 展开更多
关键词 spherically convex set spherically convex function Lipschitz-continuity uniform convergence
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