We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimen...We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimensions of the relative entropy generating sets to characterize the sub-exponential growth of the relative topological complexity.we also investigate the relations among these.Second,we introduce the notion of a relative dimension set.Moreover,using the method,we discuss the disjointness between the relative entropy zero extensions via the relative dimension sets of two extensions,which says that if the relative dimension sets of two extensions are different,then the extensions are disjoint.展开更多
Amenity trees are an essential element of most urban communities,contributing significantly to human well-being and improving environmental quality.Good knowledge of the diversity and abundance of trees in our environ...Amenity trees are an essential element of most urban communities,contributing significantly to human well-being and improving environmental quality.Good knowledge of the diversity and abundance of trees in our environment and their importance can help promote conservation,which is essential for sustainability.This study aimed at assessing the diversity and abundance of amenity trees on the premises of the International Institute of Tropical Agriculture(IITA),Ibadan Nigeria.The institute was divided into working and residential areas.The trees in the study area were identified using a walking and windshield survey.A total population of 2626 trees from 126 species and 42 families were identified on the premises of IITA.The highest tree population of 523 trees was recorded in the Tropical Crescent residential area with 321 trees of Lagerstroemia speciosa being the most frequent species.Across working and residential areas,Elaeis guineensis was the most frequent species accounting for 19.92%of the total tree population.A Shannon-Wiener Diversity Index(H’)of 3.383 and species evenness of 0.43 was obtained from the study area.The high values of diversity indices obtained indicate that IITA premises are rich in diverse tree species both indigenous and exotic hence should be referenced as a good urban landscape.The current management practices can be recommended for other institutions.展开更多
Based on the investigation of understory landscapes in mountain amenity forest in Guangdong, plant selection and spatial structure of understory landscapes were explored from the perspective of influencing factors suc...Based on the investigation of understory landscapes in mountain amenity forest in Guangdong, plant selection and spatial structure of understory landscapes were explored from the perspective of influencing factors such as terrain, stand structure, canopy density. It was proposed that plant selection for the construction of understory landscapes should use more indigenous plants, follow ecological attributes of plants and pay attention for ornamental value of plants. Three modes of constructing understory landscapes were proposed: ornamental, recreational and ecological.展开更多
In this article, the approximate amenability of semigroup algebra e1(S) is investigated, where S is a uniformly locally finite inverse semigroup. Indeed, we show that for a uniformly locally finite inverse semigroup...In this article, the approximate amenability of semigroup algebra e1(S) is investigated, where S is a uniformly locally finite inverse semigroup. Indeed, we show that for a uniformly locally finite inverse semigroup S, the notions of amenability, approximate amenability and bounded approximate amenability of e1(S) are equivalent. We use this to give a direct proof of the approximate amenability of e1 (S) for a Brandt semigroup S. Moreover, we characterize the approximate amenability of e1(S), where S is a uniformly locally finite band semigroup.展开更多
Let G be a locally compact group, H a closed amenable subgroup and u an element of the Herz Figà-Talamanca algebra of H with compact support, we prove the existence of an extension of u to G, with a good control ...Let G be a locally compact group, H a closed amenable subgroup and u an element of the Herz Figà-Talamanca algebra of H with compact support, we prove the existence of an extension of u to G, with a good control of the norm and of the support of the extension.展开更多
In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group actions.A useful tool is the support of a topological dynamic...In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group actions.A useful tool is the support of a topological dynamical system which is used to study the structure of the Banach proximal relation,and we prove that above three relations all coincide on a Banach mean equicontinuous system generated by an amenable group action.展开更多
This study is intended to recognize the importance of cold-wind, which is one of the solutions to improve urban amenity, and verify the model that can analyze creation and flow of cold-wind. For this reason, KLAM_21 M...This study is intended to recognize the importance of cold-wind, which is one of the solutions to improve urban amenity, and verify the model that can analyze creation and flow of cold-wind. For this reason, KLAM_21 Model, which was developed by the German’s Meteorological Service, was selected and used for assessment of cold-wind creation and flow. As a result, the followings have been drawn through comparison with measured data and simulated data in the study area;for a mountain area, the simulation result of velocity and direction of wind has been indicated as similar as those in measured data. For a stream area in the city, only wind direction from simulation has been consistent with measured data whereas wind velocity showed a large difference between measurement and simulation. Finally, for the downtown area, wind velocity has shown a lot of differences between simulation result and measured data. Wind direction has also shown a large difference until midnight. But after midnight, model data have become similar as measured data. According to the verification of this study, the model used in this study for using urban-amenity improvement through assessment of creation and flow of cold wind is suitable to analyze the direction of cold wind that is generated in the periphery of the city and the overall flow within the existing urban area. But the results of wind velocity have shown the uppermost limit of the modeling in the simulation. That is, it could not reflect the site characteristics sufficiently. Therefore, if parameters considering the specific regional characteristics are sufficiently reflected, the result of simulations for reliability can be substantially improved.展开更多
In this paper, we define and study polynomial entropy on an arbitrary subset and local measure theoretic polynomial entropy for any Borel probability measure on a compact metric space,and investigate the relation betw...In this paper, we define and study polynomial entropy on an arbitrary subset and local measure theoretic polynomial entropy for any Borel probability measure on a compact metric space,and investigate the relation between local measure-theoretic polynomial entropy of Borel probability measures and polynomial entropy on an arbitrary subset. Also, we establish a variational principle for polynomial entropy on compact subsets in the context of amenable group actions.展开更多
Let G be a locally compact group and let F be a closed subgroup of G × G. Pier introduced the notion of F-amenability which gives a new classification of groups. This concept generalizes the concept of amenabilit...Let G be a locally compact group and let F be a closed subgroup of G × G. Pier introduced the notion of F-amenability which gives a new classification of groups. This concept generalizes the concept of amenability and inner amenability for locally compact groups. In this paper, among other things, we extend some standard results for amenable groups to F-amenable groups and give various characterizations for F-amenable groups. A sequence of characterizations of F-amenable groups is given here by developing the well-known Flner's conditions for amenable locally compact groups. Several characterizations of inner amenability are also given.展开更多
基金supported by the NNSF of China (12201120,12171233)the Educational Research Project for Young and Middle-aged Teachers of Fujian Province (JAT200045).
文摘We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimensions of the relative entropy generating sets to characterize the sub-exponential growth of the relative topological complexity.we also investigate the relations among these.Second,we introduce the notion of a relative dimension set.Moreover,using the method,we discuss the disjointness between the relative entropy zero extensions via the relative dimension sets of two extensions,which says that if the relative dimension sets of two extensions are different,then the extensions are disjoint.
文摘Amenity trees are an essential element of most urban communities,contributing significantly to human well-being and improving environmental quality.Good knowledge of the diversity and abundance of trees in our environment and their importance can help promote conservation,which is essential for sustainability.This study aimed at assessing the diversity and abundance of amenity trees on the premises of the International Institute of Tropical Agriculture(IITA),Ibadan Nigeria.The institute was divided into working and residential areas.The trees in the study area were identified using a walking and windshield survey.A total population of 2626 trees from 126 species and 42 families were identified on the premises of IITA.The highest tree population of 523 trees was recorded in the Tropical Crescent residential area with 321 trees of Lagerstroemia speciosa being the most frequent species.Across working and residential areas,Elaeis guineensis was the most frequent species accounting for 19.92%of the total tree population.A Shannon-Wiener Diversity Index(H’)of 3.383 and species evenness of 0.43 was obtained from the study area.The high values of diversity indices obtained indicate that IITA premises are rich in diverse tree species both indigenous and exotic hence should be referenced as a good urban landscape.The current management practices can be recommended for other institutions.
基金Supported by Program of Guangdong Department of Science and Technology:Research on Technology of Restoring Ground Vegetation in Mountain Amenity Forests (2011B020309011)
文摘Based on the investigation of understory landscapes in mountain amenity forest in Guangdong, plant selection and spatial structure of understory landscapes were explored from the perspective of influencing factors such as terrain, stand structure, canopy density. It was proposed that plant selection for the construction of understory landscapes should use more indigenous plants, follow ecological attributes of plants and pay attention for ornamental value of plants. Three modes of constructing understory landscapes were proposed: ornamental, recreational and ecological.
文摘In this article, the approximate amenability of semigroup algebra e1(S) is investigated, where S is a uniformly locally finite inverse semigroup. Indeed, we show that for a uniformly locally finite inverse semigroup S, the notions of amenability, approximate amenability and bounded approximate amenability of e1(S) are equivalent. We use this to give a direct proof of the approximate amenability of e1 (S) for a Brandt semigroup S. Moreover, we characterize the approximate amenability of e1(S), where S is a uniformly locally finite band semigroup.
文摘Let G be a locally compact group, H a closed amenable subgroup and u an element of the Herz Figà-Talamanca algebra of H with compact support, we prove the existence of an extension of u to G, with a good control of the norm and of the support of the extension.
基金supported by NSF of China(11671057)NSF of Chongqing(cstc2020jcyj-msxm X0694)the Fundamental Research Funds for the Central Universities(2018CDQYST0023)。
文摘In this paper,we study the proximal relation,regionally proximal relation and Banach proximal relation of a topological dynamical system for amenable group actions.A useful tool is the support of a topological dynamical system which is used to study the structure of the Banach proximal relation,and we prove that above three relations all coincide on a Banach mean equicontinuous system generated by an amenable group action.
文摘This study is intended to recognize the importance of cold-wind, which is one of the solutions to improve urban amenity, and verify the model that can analyze creation and flow of cold-wind. For this reason, KLAM_21 Model, which was developed by the German’s Meteorological Service, was selected and used for assessment of cold-wind creation and flow. As a result, the followings have been drawn through comparison with measured data and simulated data in the study area;for a mountain area, the simulation result of velocity and direction of wind has been indicated as similar as those in measured data. For a stream area in the city, only wind direction from simulation has been consistent with measured data whereas wind velocity showed a large difference between measurement and simulation. Finally, for the downtown area, wind velocity has shown a lot of differences between simulation result and measured data. Wind direction has also shown a large difference until midnight. But after midnight, model data have become similar as measured data. According to the verification of this study, the model used in this study for using urban-amenity improvement through assessment of creation and flow of cold wind is suitable to analyze the direction of cold wind that is generated in the periphery of the city and the overall flow within the existing urban area. But the results of wind velocity have shown the uppermost limit of the modeling in the simulation. That is, it could not reflect the site characteristics sufficiently. Therefore, if parameters considering the specific regional characteristics are sufficiently reflected, the result of simulations for reliability can be substantially improved.
基金supported by Foundation in higher education institutions of He’nan Province,P. R. China(Grant No. 23A110020)National Natural Science Foundation of China (Grant No. 11401363)+4 种基金the Foundation for the Training of Young Key Teachers in Colleges and Universities in He’nan Province,P. R. China (Grant No.2018GGJS134)supported by National Natural Science Foundation of China (Gratn No.11971236)China Postdoctoral Science Foundation (Grant No. 2016M591873)China Postdoctoral Science Special Foundation (Grant No. 2017T100384)funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘In this paper, we define and study polynomial entropy on an arbitrary subset and local measure theoretic polynomial entropy for any Borel probability measure on a compact metric space,and investigate the relation between local measure-theoretic polynomial entropy of Borel probability measures and polynomial entropy on an arbitrary subset. Also, we establish a variational principle for polynomial entropy on compact subsets in the context of amenable group actions.
文摘Let G be a locally compact group and let F be a closed subgroup of G × G. Pier introduced the notion of F-amenability which gives a new classification of groups. This concept generalizes the concept of amenability and inner amenability for locally compact groups. In this paper, among other things, we extend some standard results for amenable groups to F-amenable groups and give various characterizations for F-amenable groups. A sequence of characterizations of F-amenable groups is given here by developing the well-known Flner's conditions for amenable locally compact groups. Several characterizations of inner amenability are also given.