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APPROXIMATION IN WEIGHTED HOLOMORPHIC BESOV SPACES ON POLYDISK AND UNIT BALL
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作者 Ali ABKAR 《Acta Mathematica Scientia》 2025年第5期2208-2216,共9页
We study certain weighted Bergman and weighted Besov spaces of holomorphic functions in the polydisk and in the unit ball.We seek conditions on the weight functions to guarantee that the dilations of a given function ... We study certain weighted Bergman and weighted Besov spaces of holomorphic functions in the polydisk and in the unit ball.We seek conditions on the weight functions to guarantee that the dilations of a given function converge to the same function in norm;in particular,we seek conditions on the weights to ensure that the analytic polynomials are dense in the space. 展开更多
关键词 Bergman space Besov space DILATION weight function
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An Approximation Method for Singular Trudinger-Moser Inequality
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作者 ZHU Maochun XU Wenyan JIANG Rou 《应用数学》 北大核心 2025年第1期64-70,共7页
In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to... In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to the concentration level of singular Trudinger-Moser functional on the unit ball. 展开更多
关键词 Singular Trudinger-Moser inequality approximation functional Concentration level
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Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons
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作者 AoJun Ren Jiang Yu +2 位作者 Jing Wang ZuZheng Chen XiaoMan Liu 《Earth and Planetary Physics》 EI CAS 2025年第1期159-170,共12页
Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous ... Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous quantitative analyses often simplified the chorus dispersion relation by using the cold plasma assumption.However,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic disturbances.We here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to 2018.The statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma density.The region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density decreases.In addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus waves.Compared with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those below.Furthermore,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density. 展开更多
关键词 chorus waves cold plasma approximation dispersion relations scattering rates
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Exceptional Set for Diophantine Approximation with Primes of Two Squares and Three Biquadrates
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作者 LIU Minmin ZHANG Min LI Jinjiang 《数学进展》 北大核心 2025年第1期18-36,共19页
Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for ... Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for anyε>0,the number of v∈V with v≤N such that the following inequality|λ_(1)p_(1)~2+λ_(2)p_(2)~2+λ_(3)p_(3)~4+λ_(4)p_(4)~4+λ_5p_5~4-v|<v^(-δ)has no solution in prime variables p_(1),p_(2),p_(3),p_(4),p_(5)does not exceed O(N^(29/32+2δ+ε)). 展开更多
关键词 Diophantine approximation exponential sum Davenport-Heilbronn method prime variable
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A Note for Weighted Local Hardy Spaces
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作者 ZHAO Haijing LI Baode 《数学进展》 北大核心 2025年第5期1095-1101,共7页
Inhomogeneous Calderon-Zygmund operator T maps each atom into an approximate molecule of weighted local Hardy space if and only if some approximate cancellation condition holds for T.An equivalent norm for weighted Le... Inhomogeneous Calderon-Zygmund operator T maps each atom into an approximate molecule of weighted local Hardy space if and only if some approximate cancellation condition holds for T.An equivalent norm for weighted Lebesgue space which has vanishing moments up to order s plays an important role,where s∈N. 展开更多
关键词 local Hardy space Calderon-Zygmund operator Muckenhoupt weight
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The Paley-Wiener Theorem for General Weighted Hardy Spaces on Tube Domains
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作者 HUANG Yun ZHANG Dawei 《应用数学》 北大核心 2025年第3期841-849,共9页
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen... In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights. 展开更多
关键词 Paley-Wiener Theorem Fourier transform weighted Hardy space Tube domain
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Smoluchowski-Kramers Approximation for Stochastic Differential Equations under Discretization
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作者 Li Ge 《应用概率统计》 北大核心 2025年第4期622-635,共14页
This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–M... This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–Maruyama discretization and derive its convergence rate.In particular,the solution of the discretized system converges to the solution of the first-order limit equation in the mean-square sense,and this convergence is independent of the order in which the mass parameterμand the step size h tend to zero. 展开更多
关键词 stochastic differential equations Smoluchowski-Kramers approximation driftimplicit Euler-Maruyama scheme convergence rate
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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2-complex Symmetric Weighted Composition Operators on Fock Space of C^(N)
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作者 JIANG Zhijie 《数学进展》 北大核心 2025年第1期37-49,共13页
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(... The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given. 展开更多
关键词 Fock space weighted composition operator 2-complex symmetric operator reproducing kernel function
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Auto-Weighted Neutrosophic Fuzzy Clustering for Multi-View Data
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作者 Zhe Liu Jiahao Shi +2 位作者 Dania Santina Yulong Huang Nabil Mlaiki 《Computer Modeling in Engineering & Sciences》 2025年第9期3531-3555,共25页
The increasing prevalence of multi-view data has made multi-view clustering a crucial technique for discovering latent structures from heterogeneous representations.However,traditional fuzzy clustering algorithms show... The increasing prevalence of multi-view data has made multi-view clustering a crucial technique for discovering latent structures from heterogeneous representations.However,traditional fuzzy clustering algorithms show limitations with the inherent uncertainty and imprecision of such data,as they rely on a single-dimensional membership value.To overcome these limitations,we propose an auto-weighted multi-view neutrosophic fuzzy clustering(AW-MVNFC)algorithm.Our method leverages the neutrosophic framework,an extension of fuzzy sets,to explicitly model imprecision and ambiguity through three membership degrees.The core novelty of AWMVNFC lies in a hierarchical weighting strategy that adaptively learns the contributions of both individual data views and the importance of each feature within a view.Through a unified objective function,AW-MVNFC jointly optimizes the neutrosophic membership assignments,cluster centers,and the distributions of view and feature weights.Comprehensive experiments conducted on synthetic and real-world datasets demonstrate that our algorithm achieves more accurate and stable clustering than existing methods,demonstrating its effectiveness in handling the complexities of multi-view data. 展开更多
关键词 Multi-view data neutrosophic fuzzy clustering view weight feature weight UNCERTAINTY
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Weighted Voting Ensemble Model Integrated with IoT for Detecting Security Threats in Satellite Systems and Aerial Vehicles
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作者 Raed Alharthi 《Journal of Computer and Communications》 2025年第2期250-281,共32页
Small-drone technology has opened a range of new applications for aerial transportation. These drones leverage the Internet of Things (IoT) to offer cross-location services for navigation. However, they are susceptibl... Small-drone technology has opened a range of new applications for aerial transportation. These drones leverage the Internet of Things (IoT) to offer cross-location services for navigation. However, they are susceptible to security and privacy threats due to hardware and architectural issues. Although small drones hold promise for expansion in both civil and defense sectors, they have safety, security, and privacy threats. Addressing these challenges is crucial to maintaining the security and uninterrupted operations of these drones. In this regard, this study investigates security, and preservation concerning both the drones and Internet of Drones (IoD), emphasizing the significance of creating drone networks that are secure and can robustly withstand interceptions and intrusions. The proposed framework incorporates a weighted voting ensemble model comprising three convolutional neural network (CNN) models to enhance intrusion detection within the network. The employed CNNs are customized 1D models optimized to obtain better performance. The output from these CNNs is voted using a weighted criterion using a 0.4, 0.3, and 0.3 ratio for three CNNs, respectively. Experiments involve using multiple benchmark datasets, achieving an impressive accuracy of up to 99.89% on drone data. The proposed model shows promising results concerning precision, recall, and F1 as indicated by their obtained values of 99.92%, 99.98%, and 99.97%, respectively. Furthermore, cross-validation and performance comparison with existing works is also carried out. Findings indicate that the proposed approach offers a prospective solution for detecting security threats for aerial systems and satellite systems with high accuracy. 展开更多
关键词 Intrusion Detection Cyber-Physical Systems Drone Security weighted Ensemble Voting Unmanned Vehicles Security Strategies
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Low-light image enhancement for UAVs guided by a light weighted map 被引量:1
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作者 BAI Xiaotong WANG Dianwei +2 位作者 FANG Jie LI Yuanqing XU Zhijie 《Optoelectronics Letters》 2025年第6期348-353,共6页
The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV imag... The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV images,which is inspired by the Retinex theory and guided by a light weighted map.Firstly,we propose a new network for reflectance component processing to suppress the noise in images.Secondly,we construct an illumination enhancement module that uses a light weighted map to guide the enhancement process.Finally,the processed reflectance and illumination components are recombined to obtain the enhancement results.Experimental results show that our method can suppress the noise in images while enhancing image brightness,and prevent over enhancement in bright regions.Code and data are available at https://gitee.com/baixiaotong2/uav-images.git. 展开更多
关键词 unmanned aerial vehicle retinex theory light weighted map reflectance component processing illumination enhancement module noise suppression unmanned aerial vehicle uav images low light image enhancement
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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On approximation of Bernstein-Stancu operators in movable interval
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作者 WAGN Feng-feng YU Dan-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期85-101,共17页
In the present paper,we obtain the converse results of approximation of a newly introduced genuine Bernstein-Durrmeyer operators in movable interval.We also get the moments properties of an auxiliary operator which ha... In the present paper,we obtain the converse results of approximation of a newly introduced genuine Bernstein-Durrmeyer operators in movable interval.We also get the moments properties of an auxiliary operator which has its own independent values.The moments of the auxiliary operators play important roles in establishing the main result(Theorem 4). 展开更多
关键词 Bernstein-Stancu operators movable interval approximation rates Voronovskaja's asymptotic estimate
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Relative-Density-Viewpoint-Based Weighted Kernel Fuzzy Clustering
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作者 Yuhan Xia Xu Li +2 位作者 Ye Liu Wenbo Zhou Yiming Tang 《Computers, Materials & Continua》 2025年第7期625-651,共27页
Applying domain knowledge in fuzzy clustering algorithms continuously promotes the development of clustering technology.The combination of domain knowledge and fuzzy clustering algorithms has some problems,such as ini... Applying domain knowledge in fuzzy clustering algorithms continuously promotes the development of clustering technology.The combination of domain knowledge and fuzzy clustering algorithms has some problems,such as initialization sensitivity and information granule weight optimization.Therefore,we propose a weighted kernel fuzzy clustering algorithm based on a relative density view(RDVWKFC).Compared with the traditional density-based methods,RDVWKFC can capture the intrinsic structure of the data more accurately,thus improving the initial quality of the clustering.By introducing a Relative Density based Knowledge Extraction Method(RDKM)and adaptive weight optimization mechanism,we effectively solve the limitations of view initialization and information granule weight optimization.RDKM can accurately identify high-density regions and optimize the initialization process.The adaptive weight mechanism can reduce noise and outliers’interference in the initial cluster centre selection by dynamically allocating weights.Experimental results on 14 benchmark datasets show that the proposed algorithm is superior to the existing algorithms in terms of clustering accuracy,stability,and convergence speed.It shows adaptability and robustness,especially when dealing with different data distributions and noise interference.Moreover,RDVWKFC can also show significant advantages when dealing with data with complex structures and high-dimensional features.These advancements provide versatile tools for real-world applications such as bioinformatics,image segmentation,and anomaly detection. 展开更多
关键词 Fuzzy clustering fuzzy c-means feature weighting information granule
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Weighted Attribute Based Conditional Proxy Re-Encryption in the Cloud
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作者 Xixi Yan Jing Zhang Pengyu Cheng 《Computers, Materials & Continua》 2025年第4期1399-1414,共16页
Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribu... Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources. 展开更多
关键词 Cloud service conditional proxy re-encryption user revocation weighted attribute
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A sharp lower bound for the weighted Lehmer mean involving complete p-elliptic integrals
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作者 ZHAO Tie-hong CHU Yu-ming 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期558-569,共12页
In the article,we provide a sharp lower bound for the weighted Lehmer mean of the complete p-elliptic integrals of the first and second kinds,which is the extension of the previous results for complete p-elliptic inte... In the article,we provide a sharp lower bound for the weighted Lehmer mean of the complete p-elliptic integrals of the first and second kinds,which is the extension of the previous results for complete p-elliptic integrals. 展开更多
关键词 Holder mean weighted Lehmer mean complete p-elliptic integrals
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BERGMAN PROJECTION AND TOEPLITZ OPERATORS ON WEIGHTED HARMONIC BERGMAN SPACES INDUCED BY DOUBLING WEIGHTS
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作者 Yongjiang DUAN Sawlet JUNIS Na ZHAN 《Acta Mathematica Scientia》 2025年第4期1497-1513,共17页
In this paper,it is shown that the harmonic Bergman projection P_(ω)^(h),induced by a radial,induced by a radial weightω,is bounded and onto from L^(∞)(D)to the harmonic Bloch space B_(h)if and only ifω∈D,,which ... In this paper,it is shown that the harmonic Bergman projection P_(ω)^(h),induced by a radial,induced by a radial weightω,is bounded and onto from L^(∞)(D)to the harmonic Bloch space B_(h)if and only ifω∈D,,which is a class of radial weights satisfying the two-sided doubling conditions.As an application,the bounded and compact positive Toeplitz operators T_(μ,ω)on the endpoint case weighted harmonic Bergman space L_(h,ω)^(1)(D)are characterized. 展开更多
关键词 Bergman projection Toeplitz operator harmonic Bloch space D weight
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WEIGHTED CONE-VOLUME MEASURES OF PSEUDO-CONES
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作者 Rolf SCHNEIDER 《Acta Mathematica Scientia》 2025年第1期40-51,共12页
A pseudo-cone in ℝ^(n) is a nonempty closed convex set K not containing the origin and such thatλK⊆K for allλ≥1.It is called a C-pseudo-cone if C is its recession cone,where C is a pointed closed convex cone with i... A pseudo-cone in ℝ^(n) is a nonempty closed convex set K not containing the origin and such thatλK⊆K for allλ≥1.It is called a C-pseudo-cone if C is its recession cone,where C is a pointed closed convex cone with interior points.The cone-volume measure of a pseudo-cone can be defined similarly as for convex bodies,but it may be infinite.After proving a necessary condition for cone-volume measures of C-pseudo-cones,we introduce suitable weights for cone-volume measures,yielding finite measures.Then we provide a necessary and sufficient condition for a Borel measure on the unit sphere to be the weighted cone-volume measure of some C-pseudo-cone. 展开更多
关键词 pseudo-cone surface area measure cone-volume measure weighting Minkowski type problem
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