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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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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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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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ON SOME RESULTS RELATED TO SOBER SPACES
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作者 李庆国 金梦洁 +1 位作者 苗化磷 陈思恒 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1477-1490,共14页
This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a... This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a first countable T_(0) space is sober if and only if it does not contain a∏_(2)^(0)-subspace homeomorphic either to S_(D),the natural number set equipped with the Scott topology,or to S_(1),the natural number set equipped with the cofinite topology,and it does not contain any directed closed subset without maximal elements either.Second,we show that if Y is sober,the function space TOP(X,Y)equipped with the Isbell topology(respectively,Scott topology)may be a non-sober space.Furthermore,we provide a uniform construction to d-spaces and well-filtered spaces via irreducible subset systems introduced in[9];we called this an H-well-filtered space.We obtain that,for a T_(0) space X and an H-well-filtered space Y,the function space TOP(X,Y)equipped with the Isbell topology is H-well-filtered.Going beyond the aforementioned work,we solve several open problems concerning strong d-spaces posed by Xu and Zhao in[11]. 展开更多
关键词 sober space descriptive set theory function space strong d-space product space REFLECTION
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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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Boundedness of Fractional Integrals with a Rough Kernel on the Product Triebel-Lizorkin Spaces
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作者 zhang hui-hui yu xiao +1 位作者 xiang zhong-qi ji you-qing 《Communications in Mathematical Research》 CSCD 2017年第3期259-273,共15页
By using the Littlewood-Paley decomposition and the interpolation theory, we prove the boundedness of fractional integral on the product Triebel-Lizorkin spaces with a rough kernel related to the product block spaces.
关键词 fractional integral block space Triebel-Lizorkin space product space
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ON APPROXIMATELY(p,q)-WRIGHT AFFINE FUNCTIONS AND INNER PRODUCT SPACES
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作者 Anna BAHYRYCZ Magdalena PISZCZEK 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期593-601,共9页
We prove, using the fixed point approach, some results on hyperstability (in normed spaces) of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characteriza... We prove, using the fixed point approach, some results on hyperstability (in normed spaces) of the equation that defines the generalization of p-Wright affine functions and show that they yield a simple characterization of the complex inner product spaces. 展开更多
关键词 HYPERSTABILITY p-Wright affine function complex inner product space fixedpoint theorem
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Intuitionistic Menger inner product spaces and applications to integral equations
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作者 张石生 M.GOUDARZI +1 位作者 R.SAADATI S.M.VAEZPOUR 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第4期415-424,共10页
In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the result... In this paper, first introduce and define an intuitionistic Menger inner product space, and then, obtain a new fixed point theorem in a complete intuitionistic Menger inner product space. As an application, the results are used to study the existence and uniqueness of the solution to a linear Volterra integral equation. 展开更多
关键词 intuitionistic Menger inner product space Volterra integral equation h-type t-norm fixed point theorem
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ON THE CENTRAL LIMIT THEOREM IN PRODUCT SPACES
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作者 SU ZHONGGEN 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第4期367-378,共12页
Suppose that E and F are separable Banach spaces, X and Y are independent symmetric E and F-valued random vectors respectively. This paper is devoted to the study of the central limit theorem for X Y in the injective... Suppose that E and F are separable Banach spaces, X and Y are independent symmetric E and F-valued random vectors respectively. This paper is devoted to the study of the central limit theorem for X Y in the injective and projective tensor product spaces E F and E F. Special attention is paid to l2 l2. In addition, two counter-examples are given. 展开更多
关键词 Central limit theorem injective and projective tensor product spaces Gaussian process.
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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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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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Some Results on Reverses of Cauchy-Schwarz Inequality in Inner Product Spaces
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作者 王公宝 马吉溥 《Northeastern Mathematical Journal》 CSCD 2005年第2期207-211,共5页
Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper. As an application of the main result, a formula for error estimate concerning Cauchy-Schwarz’s inequality is pro... Some new reverses of the Cauchy-Schwarz inequality in inner product spaces are presented in this paper. As an application of the main result, a formula for error estimate concerning Cauchy-Schwarz’s inequality is provided. The results obtained in the paper complement and improve some recent work about this topic. 展开更多
关键词 inner product spaces Cauchy-Schwarz's inequality reverse inequality error estimate
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