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PRODUCT TYPE OPERATORS ACTING BETWEEN WEIGHTED BERGMAN SPACES AND BLOCH TYPE SPACES
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作者 Zuoling LIU Hasi WULAN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1327-1336,共10页
For analytic functions u,ψin the unit disk D in the complex plane and an analytic self-mapφof D,we describe in this paper the boundedness and compactness of product type operators T_(u,ψ,φ)f(z)=u(z)f(φ(z))+ψ(z)f... For analytic functions u,ψin the unit disk D in the complex plane and an analytic self-mapφof D,we describe in this paper the boundedness and compactness of product type operators T_(u,ψ,φ)f(z)=u(z)f(φ(z))+ψ(z)f'(φ(z)),z∈D,acting between weighted Bergman spaces induced by a doubling weight and a Bloch type space with a radial weight. 展开更多
关键词 COMPACTNESS BOUNDEDNESS Bloch type space product type operator weighted Bergman space
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Evolving patterns of agricultural production space in China:A network-based approach
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作者 Shuhui Yang Zhongkai Li +2 位作者 Jianlin Zhou Yancheng Gao Xuefeng Cui 《Geography and Sustainability》 CSCD 2024年第1期121-134,共14页
The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have p... The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological analysis.In this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in China.The results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past decades.The little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively stable.Additionally,identified provincial communities closely resemble China's agricultural natural zones.Furthermore,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural production.Despite the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special attentions.The findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development. 展开更多
关键词 Agricultural system Complex network Agricultural production space Proximity matrix production capability
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MAXIMAL ELEMENTS OF A FAMILY OF G_B-MAJORIZED MAPPINGS IN PRODUCT FC-SPACES AND APPLICATIONS 被引量:2
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第12期1607-1618,共12页
A new family of GB-majorized mappings from a topological space into a finite continuous topological spaces (in short, FC-space) involving a better admissible set-valued mapping is introduced. Some existence theorems... A new family of GB-majorized mappings from a topological space into a finite continuous topological spaces (in short, FC-space) involving a better admissible set-valued mapping is introduced. Some existence theorems of maximal elements for the family of GB-majorized mappings are proved under noncompact setting of product FCspaces. Some applications to fixed point and system of minimax inequalities are given in product FC-spaces. These theorems improve, unify and generalize many important results in recent literature. 展开更多
关键词 maximal element family of GB-majorized mappings fixed point system of minimax inequalities product fc-space
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Heritage Communities in Consumer Contexts Spatial Production of Tourism Research-Take Qixian Zhao Yu Historical City as an Example
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作者 BAI Zhao-yi ZHU Jun-jie WEN Jia-hao 《Journal of Literature and Art Studies》 2024年第1期95-108,共14页
Taking Zhaoyu Historical City in Qixian County as an example,this paper explores the production process of tourism space in Zhaoyu Historical City in the context of consumption,based on Lefebvre's triadic dialecti... Taking Zhaoyu Historical City in Qixian County as an example,this paper explores the production process of tourism space in Zhaoyu Historical City in the context of consumption,based on Lefebvre's triadic dialectic theory.The study reveals that,driven by the development of tourism,subjects such as the government and planners possess absolute dominance over spatial representations,while residents demonstrate receptive and adaptive action strategies and social relations are reproduced,presenting a harmonious state.Further exploring the tourism community in the environmental performance of the subject of action,social relations,consumption demand,daily life practice,cultural capital,etc.,the daily life practice of the tourism community has transcended the original logic of tourism spatial production and has a certain extension.The mechanism analysis in this paper can help guide the healthy development of tourism space in the neighboring historical cities or communities and achieve the dual purpose of promoting the economic development of the community and heritage protection. 展开更多
关键词 spatial production theory tourism space consumption context heritage community ZhaoYu Historical City
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基于Cite space的我国蔬菜制种产业研究热点与趋势分析
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作者 张悦 张爱宁 李滋婷 《管理科学与研究(中英文版)》 2024年第3期6-12,共7页
运用可视化工具Cite Space和文献计量方法,对刊载在中国知网数据库所有与蔬菜制种相关主题的1212篇相关文献进行分析,并总结了我国蔬菜制种产业的热点及发展趋势。研究发现,蔬菜制种产业的研究热点主要集中在制种技术、杂交制种、种子... 运用可视化工具Cite Space和文献计量方法,对刊载在中国知网数据库所有与蔬菜制种相关主题的1212篇相关文献进行分析,并总结了我国蔬菜制种产业的热点及发展趋势。研究发现,蔬菜制种产业的研究热点主要集中在制种技术、杂交制种、种子产量、杂交授粉、杂种纯度等方面。我们建议后续应加强核心技术攻关,加快生物技术在蔬菜制种上的应用、强化基地建设,提高蔬菜制种产业化水平、加强研究主体间的合作与交流,重视制种人才培养,打造智慧农业。本研究可为进一步完善我国蔬菜制种产业提供借鉴。 展开更多
关键词 蔬菜制种 研究热点 知识图谱 Cite space
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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Boundedness of Hausdorff operators on some product Hardy type spaces 被引量:13
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作者 CHEN Jie-cheng FAN Da-shan ZHANG Chun-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第1期114-126,共13页
We study Hausdorff operators on the product Besov space B0,1 1 (Rn ×Rm) and on the local product Hardy space h1 (Rn ×Rm). We establish some boundedness criteria for Hausdorff operators on these function ... We study Hausdorff operators on the product Besov space B0,1 1 (Rn ×Rm) and on the local product Hardy space h1 (Rn ×Rm). We establish some boundedness criteria for Hausdorff operators on these function spaces. 展开更多
关键词 Hausdorff operator atomic decomposition product Besov space product Hardy space productlocal Hardy space.
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Agricultural Land Suitability of Production Space in the Taihang Mountains, China 被引量:7
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作者 GENG Shoubao SHI Peili +1 位作者 ZONG Ning ZHU Wanrui 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1024-1038,共15页
The contradiction between the shortage of land for agriculture due to rapid expansion of industrialization and urbanization and increasing population pressure is projected to impose great threats to future food securi... The contradiction between the shortage of land for agriculture due to rapid expansion of industrialization and urbanization and increasing population pressure is projected to impose great threats to future food security.Agricultural land suitability evaluation is an effective approach to improve the utilization of land resources for crop production and thus enhance the capacity of food provision.In this study, we evaluated the land suitability for agriculture of the production space in the Taihang Mountains by three steps: establishing indicator system, determining weights for indicators, and constructing a fuzzy matter-element model to assess the grades of suitability.Results showed that the land suitability had a significant linear correlation with potential crop yields, indicating our evaluation was effective to predict crop production.The spatial pattern of land suitability for crop production demonstrated that land with higher suitability was generally located in piedmont plains and basins, while land with lower suitability was mostly situated in mountainous areas.The area of highly, moderately, marginally suitable and unsuitable land for agriculture was 32.13%, 28.58%, 37.49% and 1.80% of the production space, respectively.However, the correlation degree analysis indicated that the requirements of these four suitability grades were currently not satisfied but could be potentially fulfilled.In terms of indicator weights, soil properties were much more important than topography and location conditions to influence the grades of suitability.Among all indicators, slope, soil organic matter, soil texture and soil depth were the most influential factors, so slope farming prevention and organic fertilization were most likely to improve land suitability for agriculture.Compared the outputs of our land suitability evaluation model with the distribution of the existing croplands, we found that about 66.52% of marginally suitable and 54.55% of unsuitable land for agriculture were currently used for croplands.Therefore, de-farming policy should be implemented in areas of these two suitability grades.In contrast, cropland expansion was encouraged in the land that was highly or moderately suitable for agriculture.Our evaluation of agricultural land suitability is beneficial for future land use planning and decision-making in the Taihang Mountains. 展开更多
关键词 AGRICULTURAL land SUITABILITY MATTER-ELEMENT model productION space the Taihang MOUNTAINS
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Integrability of the general product Hardy operators on the product Hardy spaces 被引量:9
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作者 ZHU Xiang-rong CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第2期225-233,共9页
In this paper,we prove that the general product Hardy operators are bounded from the product Hardy space H1n(Rm1×···×Rmn) to L1(R(∑ni=1mi).
关键词 product Hardy operator product Hardy space atom decomposition.
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SHARP BOUNDS FOR HARDY OPERATORS ON PRODUCT SPACES 被引量:4
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作者 魏明权 燕敦验 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期441-449,共9页
In this article, we obtain the sharp bounds from LP(Gn) to the space wLP(Gn) for Hardy operators on product spaces. More generally, the precise norms of Hardy operators on product spaces from LP(Gn) to the space... In this article, we obtain the sharp bounds from LP(Gn) to the space wLP(Gn) for Hardy operators on product spaces. More generally, the precise norms of Hardy operators on product spaces from LP(Gn) to the space LPI (Gn) are obtained. 展开更多
关键词 Hardy operators product spaces wLP(Gn) LPI(Gn) NORM
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:4
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作者 DINGXie-ping 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期618-626,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 family of set-valued mapping nonempty intersection theorem system of generalized vector equilibrium problem product G-convex space
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Boundedness of Caldero'n-Zygmund operators in product Hardy spaces 被引量:2
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作者 HAN Yong-sheng YANG Da-chun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第3期321-335,共15页
By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé i... By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé is established. 展开更多
关键词 Hardy space product domain Calderón-Zygmund operator vector-valued operator
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SOME ROUGH OPERATORS ON PRODUCT SPACES 被引量:2
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作者 Chen Jiecheng and Wang Silei (Zhejiang University, China) 《Analysis in Theory and Applications》 2001年第1期48-69,共22页
In this survey report, we shall mainly summarize some recent progress, interesting problems and typical methods used in the theory related to rough Marcinkiewicz integrals and rough singular integrals on product space... In this survey report, we shall mainly summarize some recent progress, interesting problems and typical methods used in the theory related to rough Marcinkiewicz integrals and rough singular integrals on product spaces. In addition, we give new proofs for some known results. 展开更多
关键词 MATH In SOME ROUGH OPERATORS ON product spaceS BMO
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The Loeb Space of Denumerable Infinite Dimensional Probability Product Measure Spaces 被引量:2
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作者 陈东立 《Northeastern Mathematical Journal》 CSCD 2003年第3期249-253,共5页
Let {(Xi, Si, μi) : i ℃ N} be a sequence of probability measure spaces and (*Xi, L(*Si), L(*μi)) be the Loeb measure space with respect to (Xi, Si, μi) for i ℃ N. Let X =× Xi, S = ×Si,μ = ×μi. We... Let {(Xi, Si, μi) : i ℃ N} be a sequence of probability measure spaces and (*Xi, L(*Si), L(*μi)) be the Loeb measure space with respect to (Xi, Si, μi) for i ℃ N. Let X =× Xi, S = ×Si,μ = ×μi. We prove that × L(*Si) CL(*S) and in embedding meaning. 展开更多
关键词 denumerable infinite dimensional product measure space Loeb measure space internal set external set
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MAXIMAL ELEMENTS FOR G_B-MAJORIZED MAPPINGS IN PRODUCT G_CONVEX SPACES AND APPLICATIONS (Ⅱ) 被引量:1
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第9期1017-1024,共8页
A new family of set_valued mappings from a topological space into generalized convex spaces was introduced and studied. By using the continuous partition of unity theorem and Brouwer fixed point theorem, several exist... A new family of set_valued mappings from a topological space into generalized convex spaces was introduced and studied. By using the continuous partition of unity theorem and Brouwer fixed point theorem, several existence theorems of maximal elements for the family of set_valued mappings were proved under noncompact setting of product generalized convex spaces. These theorems improve, unify and generalize many important results in recent literature. 展开更多
关键词 maximal element family of G B_ majorized mappings product G_ convex space
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MAXIMAL ELEMENTS FOR G_B-MAJORIZED MAPPINGS IN PRODUCT G-CONVEX SPACES AND APPLICATIONS (Ⅰ) 被引量:1
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期659-672,共14页
A new family of set_valued mappings from a topological space into generalized convex spaces was introduced and studied. By using the continuous partition of unity theorem and Brouwer fixed point theorem, several exist... A new family of set_valued mappings from a topological space into generalized convex spaces was introduced and studied. By using the continuous partition of unity theorem and Brouwer fixed point theorem, several existence theorems of maximal elements for the family of set_valued mappings were proved under noncompact setting of product generalized convex spaces. These theorems improve, unify and generalize many important results in recent literature. 展开更多
关键词 maximal element family of G B_ majorized mappings product G_ convex space
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Risk measures with comonotonic subadditivity or convexity on product spaces 被引量:1
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作者 WEI Lin-xiao MA Yue HU Yi-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第4期407-417,共11页
In this paper, by an axiomatic approach, we propose the concepts of comonotonic subadditivity and comonotonic convex risk measures for portfolios, which are extensions of the ones introduced by Song and Yan (2006). ... In this paper, by an axiomatic approach, we propose the concepts of comonotonic subadditivity and comonotonic convex risk measures for portfolios, which are extensions of the ones introduced by Song and Yan (2006). Representation results for these new introduced risk measures for portfolios are given in terms of Choquet integrals. Links of these newly introduced risk measures to multi-period comonotonic risk measures are represented. Finally, applications of the newly introduced comonotonic coherent risk measures to capital allocations are provided. 展开更多
关键词 Choquet integral comonotonic subadditivity risk measure comonotonic convex risk measure multi-period risk measure capital allocation product space.
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Grain production space reconstruction and land system function tradeoffs in China 被引量:2
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作者 Fei Li Zhangxuan Qin +4 位作者 Xiaolin Liu Zehui Chen Xiaoli Wei Qiumeng Zhang Min Lei 《Geography and Sustainability》 2021年第1期22-30,共9页
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve... Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis. 展开更多
关键词 Land system function TRADEOFFS SYNERGY Grain production space reconstruction Set Pair Analysis
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RELAXED INERTIAL METHODS FOR SOLVING SPLIT VARIATIONAL INEQUALITY PROBLEMS WITHOUT PRODUCT SPACE FORMULATION 被引量:1
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作者 Grace Nnennaya OGWO Chinedu IZUCHUKWU Oluwatosin Temitope MEWOMO 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期1701-1733,共33页
Many methods have been proposed in the literature for solving the split variational inequality problem.Most of these methods either require that this problem is transformed into an equivalent variational inequality pr... Many methods have been proposed in the literature for solving the split variational inequality problem.Most of these methods either require that this problem is transformed into an equivalent variational inequality problem in a product space,or that the underlying operators are co-coercive.However,it has been discovered that such product space transformation may cause some potential difficulties during implementation and its approach may not fully exploit the attractive splitting nature of the split variational inequality problem.On the other hand,the co-coercive assumption of the underlying operators would preclude the potential applications of these methods.To avoid these setbacks,we propose two new relaxed inertial methods for solving the split variational inequality problem without any product space transformation,and for which the underlying operators are freed from the restrictive co-coercive assumption.The methods proposed,involve projections onto half-spaces only,and originate from an explicit discretization of a dynamical system,which combines both the inertial and relaxation techniques in order to achieve high convergence speed.Moreover,the sequence generated by these methods is shown to converge strongly to a minimum-norm solution of the problem in real Hilbert spaces.Furthermore,numerical implementations and comparisons are given to support our theoretical findings. 展开更多
关键词 split variational inequality problems relaxation technique inertial extrapolation minimum-norm solutions product space formulation half-spaces
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Rearrangement Inequality and Chebyshev's Sum Inequality on Positive Tensor Products of Orlicz Sequence Space with Banach Lattice 被引量:1
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作者 Wei-Kai Lai 《Journal of Mathematics and System Science》 2014年第8期574-578,共5页
Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Freml... Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Fremlin projective tensor product of lφ with a Banach lattice X, and in lφ iX, the Wittstock injective tensor product of lφ with a Banach lattice X. 展开更多
关键词 Rearrangement inequality Chebyshev's sum inequality injective tensor product projective tensor product Orlicz sequence space
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