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
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
The growth of agricultural labor productivity in major grain producing areas arises from the increase in production factors or improvement of efficiency,and is related to the sustainability of agricultural economic gr...The growth of agricultural labor productivity in major grain producing areas arises from the increase in production factors or improvement of efficiency,and is related to the sustainability of agricultural economic growth and national food security. We study the growth path of agricultural labor productivity in 13 major grain producing areas of China,and the analysis results show that from the relative endowments of land and labor in major grain producing areas,the growth rate of the output value per unit of labor is higher than that of the productivity per unit of land; in essence,this growth path of increasing the output value relying on increasing the production factor inputs is the reduction of labor,and the reduction of agricultural labor has a great elasticity of impact on the total value of agricultural production. In the case of stable future number of agricultural labor in China,the growth of agricultural labor productivity will be impossible to rely more on the increase in agricultural production factor inputs,and the growth path of agricultural economy still has to rely on the improvement of land productivity and take the efficiency-based path.展开更多
A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco...A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance）. In this study, an interval-probabilistic agricultural production structure optimization model （IPAPSOM） is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying （or risk of violating） system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.展开更多
Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extens...Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extensive stage.China’s economy has shifted from a high-speed growth phase to a high-quality development phase.In this study,we analyzed three major urban agglomerations’total factor productivity index dynamically by means of Malmquist productivity i?ndex method.The results showed that MPI of Beijing-Tianjin-Hebei urban agglomeration was the highest,as the reasons of the effectiveness of dual-wheel driving both the technology progress and the cluster scale.The mean of MPI of Yangtze River Delta urban agglomeration was fallen into decline by an average of 1.3%annually due to the rate of increase of the size of the cluster towards to optimal frontier was inferior to the relative risk reduction of technology progress.Pearl River Delta urban agglomeration MPI declined by an average of 2.2%annually as a result of the contribution of technology progress reducing.The study of the economic performance of three major urban agglomerations provides a theoretical basis and important practical value for urban development of high quality optimization.展开更多
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
文摘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.
文摘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.
基金Supported by Humanity and Social Science Youth Foundation of Ministry of Education of China in 2014
文摘The growth of agricultural labor productivity in major grain producing areas arises from the increase in production factors or improvement of efficiency,and is related to the sustainability of agricultural economic growth and national food security. We study the growth path of agricultural labor productivity in 13 major grain producing areas of China,and the analysis results show that from the relative endowments of land and labor in major grain producing areas,the growth rate of the output value per unit of labor is higher than that of the productivity per unit of land; in essence,this growth path of increasing the output value relying on increasing the production factor inputs is the reduction of labor,and the reduction of agricultural labor has a great elasticity of impact on the total value of agricultural production. In the case of stable future number of agricultural labor in China,the growth of agricultural labor productivity will be impossible to rely more on the increase in agricultural production factor inputs,and the growth path of agricultural economy still has to rely on the improvement of land productivity and take the efficiency-based path.
基金funded by the National Natural Science Foundation of China (41130748, 41101162)the Key Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-EW-304)
文摘A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance）. In this study, an interval-probabilistic agricultural production structure optimization model （IPAPSOM） is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying （or risk of violating） system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.
文摘Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extensive stage.China’s economy has shifted from a high-speed growth phase to a high-quality development phase.In this study,we analyzed three major urban agglomerations’total factor productivity index dynamically by means of Malmquist productivity i?ndex method.The results showed that MPI of Beijing-Tianjin-Hebei urban agglomeration was the highest,as the reasons of the effectiveness of dual-wheel driving both the technology progress and the cluster scale.The mean of MPI of Yangtze River Delta urban agglomeration was fallen into decline by an average of 1.3%annually due to the rate of increase of the size of the cluster towards to optimal frontier was inferior to the relative risk reduction of technology progress.Pearl River Delta urban agglomeration MPI declined by an average of 2.2%annually as a result of the contribution of technology progress reducing.The study of the economic performance of three major urban agglomerations provides a theoretical basis and important practical value for urban development of high quality optimization.
基金Project supported by the Natural Science Foundation of Sichuan Education Department of China (Nos.2003A081 and SZD0406)
文摘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.
