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
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
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
The connotation of "amenity value" was elaborated,construction practices of "rural amenities" in Taiwan were reviewed,and its role in improving agricultural production environment and operation pat...The connotation of "amenity value" was elaborated,construction practices of "rural amenities" in Taiwan were reviewed,and its role in improving agricultural production environment and operation pattern,promoting rural economic development and quality of rural residents was highlighted.On this basis,a new rural value system was established from the perspectives of agricultural functions,industrial forms and economic forms,and the concept of "rural amenities" was defined.Moreover,the development targets of "rural amenities" were analyzed,including the overall objectives and those specific ones from 3 aspects:production,life and ecology,and finally suggestions on the development of "rural amenities" were proposed,that is,elaborate production,elegant life and refined ecology.Elaborate production focuses on maintaining the diversity of agricultural functions,promoting the upgrade and transformation of agriculture from the aspects of agricultural growth drivers,agricultural production mode,agricultural operation subjects,agricultural operation pattern,agricultural functions,and tries to bring new concepts to agricultural production and operation patterns through developing recreational agriculture and LOHAS rural tourism (LOHAS refers to Lifestyles of Health and Sustainability);elegant life emphasizes the optimization of rural communities,and the protection of cultural relics in rural areas;refined ecology highlights the construction of "rural amenities" from 3 aspects of rural ecosystem,rural living environment and farmland eco-environment.展开更多
This paper develops a two-regional growth model with amenity, capital accumulation and regional public goods with public goods and fiscal policies. The economy consists of two regions and each region consists of the i...This paper develops a two-regional growth model with amenity, capital accumulation and regional public goods with public goods and fiscal policies. The economy consists of two regions and each region consists of the industrial sector and public sector. The industrial sector provides goods in perfectly competitive markets. The public sector, which is financed by the regional government’s tax incomes, supplies regional public goods. The public goods affect both firms and households. We show how to find equilibrium values of the dynamic system and simulate model. Then, we carry out comparative statics analysis with regard to parameter changes in tax rates, congestion and amenity. Our comparative statics analysis provides some important insights. For instance, a main difference between the effects of increasing the two regions’ tax rates on the output is that as the technologically advanced region’s (the other region’s) tax rate on the industrial sector is increased, the national industrial output, national capital employed by the economy, and the national wealth are increased (reduced). In the region which increases the tax rate, the wage rate, consumption and wealth per capita, output per labor force, the population, and land rent are increased, and the corresponding variables in the other region are reduced.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
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
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 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The connotation of "amenity value" was elaborated,construction practices of "rural amenities" in Taiwan were reviewed,and its role in improving agricultural production environment and operation pattern,promoting rural economic development and quality of rural residents was highlighted.On this basis,a new rural value system was established from the perspectives of agricultural functions,industrial forms and economic forms,and the concept of "rural amenities" was defined.Moreover,the development targets of "rural amenities" were analyzed,including the overall objectives and those specific ones from 3 aspects:production,life and ecology,and finally suggestions on the development of "rural amenities" were proposed,that is,elaborate production,elegant life and refined ecology.Elaborate production focuses on maintaining the diversity of agricultural functions,promoting the upgrade and transformation of agriculture from the aspects of agricultural growth drivers,agricultural production mode,agricultural operation subjects,agricultural operation pattern,agricultural functions,and tries to bring new concepts to agricultural production and operation patterns through developing recreational agriculture and LOHAS rural tourism (LOHAS refers to Lifestyles of Health and Sustainability);elegant life emphasizes the optimization of rural communities,and the protection of cultural relics in rural areas;refined ecology highlights the construction of "rural amenities" from 3 aspects of rural ecosystem,rural living environment and farmland eco-environment.
文摘This paper develops a two-regional growth model with amenity, capital accumulation and regional public goods with public goods and fiscal policies. The economy consists of two regions and each region consists of the industrial sector and public sector. The industrial sector provides goods in perfectly competitive markets. The public sector, which is financed by the regional government’s tax incomes, supplies regional public goods. The public goods affect both firms and households. We show how to find equilibrium values of the dynamic system and simulate model. Then, we carry out comparative statics analysis with regard to parameter changes in tax rates, congestion and amenity. Our comparative statics analysis provides some important insights. For instance, a main difference between the effects of increasing the two regions’ tax rates on the output is that as the technologically advanced region’s (the other region’s) tax rate on the industrial sector is increased, the national industrial output, national capital employed by the economy, and the national wealth are increased (reduced). In the region which increases the tax rate, the wage rate, consumption and wealth per capita, output per labor force, the population, and land rent are increased, and the corresponding variables in the other region are reduced.
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.
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.
