A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the app...A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the appropriate development strategy and achieve sustainable development. The major function oriented zoning plays a role in spatial coordination mainly＇ by spatial guidance and restriction, so. the proposal of major function oriented zoning gives a new train of thought to generate a coordination evaluation of economy-society and the resource-environment system, From the view of major function oriented zoning that considers resource environmental bearing capacity, existing development density and development potential, this paper constructs an index system and model of coordination evahtation with a case study on Pearl River Delta. The results have shown： （I） It can reveal the conflicts of economic-social development and resource-environment quality to ac- curately consider resource environmental bearing capacity, existing development densio~ and development po- tential; （2） The coordination degree between social-economy system and resource-environment system in Pearl River Delta continued to decline in the past 10 years. The spatial extent of coordination evoh,es.from coordina- tion in the whole Pearl River Delta to imbalance in the core areas, and at present, the uncoordinated areas have already diffused from core areas to the outlying regions： （3） Most regions of the Pearl River Delta are in uncoordinated condition When considering the coordination degree of economic-social development and resollrceenvironment quality, not as coordinated as some scholars considered.展开更多
Author of this paper introduced the formation and development, main viewpoints, and framework of the theory of soil and water ecology, as well as the role and value of realizing the sustainable utilization of soil and...Author of this paper introduced the formation and development, main viewpoints, and framework of the theory of soil and water ecology, as well as the role and value of realizing the sustainable utilization of soil and water ecological resources, the sustainable maintenance of ecological environment, and the sustainable development of economy and society. The paper argued that in the current era, it is imperative to maintain the integrity and continuity of soil and water ecology and culture, emphasize the planning and construction of soil and water ecological infrastructure, and ensure the service functions of urban ecosystem, so as to realize the sustainable utilization of soil and water ecological resources, and the sustainable maintenance of ecological environment, and the sustainable development of economy and society.展开更多
Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the la...Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the largest hydrodynamic thrust bearings ever built （external diameter 5,200 mm, axial load equals approximately 3,600 t）. This paper is an attempt to propose a new thrust bearing design with the use of the state-of-the-art technologies and simulation techniques that demonstrate a reduction of friction power losses generated by the thrust bearing. This paper is divided into two parts. Within the first one, the original thrust bearing design which was implemented in the generators is described. Related calculation results based on a TEHD （thermo-elasto-hydrodynamic） calculation software used by Alstom will be presented. A comparison between measurement results gathered in the 1980s is given. In the second part, a potential solution of a more beneficial bearing design is described. The proposed thrust bearing design modification is an implementation of Alstom＇s PolypadTM coating. This modern polymer （PEEK） coating material has already been used by Alstom in projects around the world for many years. This coating allows pushing the operating parameters limits toward higher temperatures and lower oil film thicknesses far beyond the limits known for the conventional bearing materials.展开更多
基金supported by National Social Science Fund(Grant No. 06&ZD038)The 11th Five-Year Planning programme of philosophy and Social Science of Guangdong(Grant NO.07D04)
文摘A reasonable coordination degree assessment of the social-economic development level and the resource-environment quality level are essential to ident the key factory of the development, and vital to determine the appropriate development strategy and achieve sustainable development. The major function oriented zoning plays a role in spatial coordination mainly＇ by spatial guidance and restriction, so. the proposal of major function oriented zoning gives a new train of thought to generate a coordination evaluation of economy-society and the resource-environment system, From the view of major function oriented zoning that considers resource environmental bearing capacity, existing development density and development potential, this paper constructs an index system and model of coordination evahtation with a case study on Pearl River Delta. The results have shown： （I） It can reveal the conflicts of economic-social development and resource-environment quality to ac- curately consider resource environmental bearing capacity, existing development densio~ and development po- tential; （2） The coordination degree between social-economy system and resource-environment system in Pearl River Delta continued to decline in the past 10 years. The spatial extent of coordination evoh,es.from coordina- tion in the whole Pearl River Delta to imbalance in the core areas, and at present, the uncoordinated areas have already diffused from core areas to the outlying regions： （3） Most regions of the Pearl River Delta are in uncoordinated condition When considering the coordination degree of economic-social development and resollrceenvironment quality, not as coordinated as some scholars considered.
文摘Author of this paper introduced the formation and development, main viewpoints, and framework of the theory of soil and water ecology, as well as the role and value of realizing the sustainable utilization of soil and water ecological resources, the sustainable maintenance of ecological environment, and the sustainable development of economy and society. The paper argued that in the current era, it is imperative to maintain the integrity and continuity of soil and water ecology and culture, emphasize the planning and construction of soil and water ecological infrastructure, and ensure the service functions of urban ecosystem, so as to realize the sustainable utilization of soil and water ecological resources, and the sustainable maintenance of ecological environment, and the sustainable development of economy and society.
文摘Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the largest hydrodynamic thrust bearings ever built （external diameter 5,200 mm, axial load equals approximately 3,600 t）. This paper is an attempt to propose a new thrust bearing design with the use of the state-of-the-art technologies and simulation techniques that demonstrate a reduction of friction power losses generated by the thrust bearing. This paper is divided into two parts. Within the first one, the original thrust bearing design which was implemented in the generators is described. Related calculation results based on a TEHD （thermo-elasto-hydrodynamic） calculation software used by Alstom will be presented. A comparison between measurement results gathered in the 1980s is given. In the second part, a potential solution of a more beneficial bearing design is described. The proposed thrust bearing design modification is an implementation of Alstom＇s PolypadTM coating. This modern polymer （PEEK） coating material has already been used by Alstom in projects around the world for many years. This coating allows pushing the operating parameters limits toward higher temperatures and lower oil film thicknesses far beyond the limits known for the conventional bearing materials.
