Very Large Floating Structures (VLFS) have drawn considerable attention recently due to their potential significance in the exploitation of ocean resources and in the utilization of ocean space. Efficient and accurate...Very Large Floating Structures (VLFS) have drawn considerable attention recently due to their potential significance in the exploitation of ocean resources and in the utilization of ocean space. Efficient and accurate estimation of their hydroelastic responses to waves is very important for the design. Recently, an efficient numerical algorithm was developed by Ertekin and Kim (1999). However, in their analysis, the linear Level I Green-Naghdi (GN) theory is employed to describe fluid dynamics instead of the conventional linear wave (LW) theory of finite water depth. They claimed that this linear level I GN theory provided better predictions of the hydroelastic responses of VLFS than the linear wave theory. In this paper, a detailed derivation is given in the conventional linear wave theory framework with the same quantity as used in the linear level I GN theory framework. This allows a critical comparison between the linear wave theory and the linear level I GN theory. It is found that the linear level I GN theory can be regarded as an approximation to the linear wave theory of finite water depth. The consequences of the differences between these two theories in the predicted hydroelastic responses are studied quantitatively. And it is found that the linear level I GN theory is not superior to the linear wave theory. Finally, various factors affecting the hydroelastic response of VLFS are studied with the implemented algorithm.展开更多
This article takes 2016-2022 as the inspection period to construct an evaluation index system for the green development level of the new energy vehicle industry.The entropy method and comprehensive index are used to m...This article takes 2016-2022 as the inspection period to construct an evaluation index system for the green development level of the new energy vehicle industry.The entropy method and comprehensive index are used to measure the green development level of the new energy vehicle industry in Chongqing,and compared with neighboring provinces such as Yunnan,Guizhou,and Sichuan.Policy recommendations are proposed to promote the development of the new energy vehicle industry in Chongqing City.展开更多
This study investigates the coupling and coordination relationship between tourism industry development and the level of green consumption across 30 provinces in China's mainland(excluding Xizang).An analytical fr...This study investigates the coupling and coordination relationship between tourism industry development and the level of green consumption across 30 provinces in China's mainland(excluding Xizang).An analytical framework for evaluating the coupling and coordination between tourism development and green consumption is constructed,employing a modified coupling model and exploratory spatial analysis to examine their interactive dynamics as well as their spatiotemporal characteristics.The findings indicate that:(1)From 2011 to 2022,the national level of tourism development exhibited wave-like growth,while the overall level of green consumption remained stable.Significant regional disparities exist between the two,presenting a spatial pattern of“higher in the east and lower in the west.”(2)The coupling coordination degree between the two systems increased steadily from 0.562 to 0.604,reaching an overall coordinated state.A non-equilibrium pattern has emerged,characterized by“leading in the eastern region,catching up in the central region,improving in the western region,and under pressure in the northeastern region.”Inter-provincial differences remain evident but show signs of convergence.(3)Five major influencing factors-energy consumption,urbanization,population size,transportation infrastructure,and government regulation-exhibit significant spatiotemporal heterogeneity,with their effects showing clear regional adaptability in both magnitude and direction.Based on these findings,it is recommended to promote regionally differentiated development strategies,strengthen cross-provincial coordination mechanisms,and implement precise regulatory policies aligned with local development stages to foster high-level coordination between tourism development and green consumption.展开更多
This paper investigated the analyses of removal of Methylene Blue (MB) and Brilliant Green (BG) dyes from aqueous solutions by adsorption on activated carbon prepared by chemical activation of coconut shell, eucalyptu...This paper investigated the analyses of removal of Methylene Blue (MB) and Brilliant Green (BG) dyes from aqueous solutions by adsorption on activated carbon prepared by chemical activation of coconut shell, eucalyptus tree, corn cob and flamboyant pod. It was found that the carbon pores increased after carbonization and activation processes. The maximum percentage MB removal was obtained as 95.0% for coconut shell, 93.2% for eucalyptus tree, 99.9% for corn cob, and 99.7% for flamboyant pod. Also, the maximum percentage BG removal was obtained as 97.0% for coconut shell, 98.2% for eucalyptus tree, 99.6% for corn cob, and 99.6% for flamboyant pod. The adsorption isotherms of the adsorption process were studied, and Freundlich model showed the best fit with the equilibrium data. To optimize the operating conditions, the effects of contact time, adsorbent dosage, and pH were investigated by two levels of factorial experimental design method and adsorbent dosage was found as the most significant factor.展开更多
A fundamental shift in the regional development pattern is crucial to achieving a comprehensive green transformation in China.Currently,innovation-driven green development is a significant strategic option for regiona...A fundamental shift in the regional development pattern is crucial to achieving a comprehensive green transformation in China.Currently,innovation-driven green development is a significant strategic option for regional development.As the main body of innovation and the basic unit of regional composition,enterprises have a profound impact on the development of regional economy,society,ecology,and other aspects.However,considering China’s vast territory and significant regional differences in natural environment and industrial structure,it’s necessary to further explore the specific impact paths of regional green development driven by enterprise innovation.Therefore,taking industrial enterprises as an example,based on the panel data of 30 provinces in China from 2016 to 2020,this study verifies the impact of industrial enterprise innovation on the regional green development level by constructing a parallel multiple mediating effect model and dividing the economy into eastern,central,and western regions to discuss the specific impact paths.The results show that industrial enterprise innovation has a significant positive effect on regional green development level,via different influencing paths in each region:(1)The eastern region improves the regional green development level by narrowing the urban-rural income gap;(2)The central region improves the regional green development level by reducing resource dependence;and(3)The western region raises the regional green development level by improving the rationalization of industrial structure.展开更多
基金by the National Natural Science Foundation of China(50039010)the Science and Technology Development Foundation of Shanghai Municipal Government(00XD14015)
文摘Very Large Floating Structures (VLFS) have drawn considerable attention recently due to their potential significance in the exploitation of ocean resources and in the utilization of ocean space. Efficient and accurate estimation of their hydroelastic responses to waves is very important for the design. Recently, an efficient numerical algorithm was developed by Ertekin and Kim (1999). However, in their analysis, the linear Level I Green-Naghdi (GN) theory is employed to describe fluid dynamics instead of the conventional linear wave (LW) theory of finite water depth. They claimed that this linear level I GN theory provided better predictions of the hydroelastic responses of VLFS than the linear wave theory. In this paper, a detailed derivation is given in the conventional linear wave theory framework with the same quantity as used in the linear level I GN theory framework. This allows a critical comparison between the linear wave theory and the linear level I GN theory. It is found that the linear level I GN theory can be regarded as an approximation to the linear wave theory of finite water depth. The consequences of the differences between these two theories in the predicted hydroelastic responses are studied quantitatively. And it is found that the linear level I GN theory is not superior to the linear wave theory. Finally, various factors affecting the hydroelastic response of VLFS are studied with the implemented algorithm.
文摘This article takes 2016-2022 as the inspection period to construct an evaluation index system for the green development level of the new energy vehicle industry.The entropy method and comprehensive index are used to measure the green development level of the new energy vehicle industry in Chongqing,and compared with neighboring provinces such as Yunnan,Guizhou,and Sichuan.Policy recommendations are proposed to promote the development of the new energy vehicle industry in Chongqing City.
基金supported by the National Social Science Fund of China(Grant No.23BJY142).
文摘This study investigates the coupling and coordination relationship between tourism industry development and the level of green consumption across 30 provinces in China's mainland(excluding Xizang).An analytical framework for evaluating the coupling and coordination between tourism development and green consumption is constructed,employing a modified coupling model and exploratory spatial analysis to examine their interactive dynamics as well as their spatiotemporal characteristics.The findings indicate that:(1)From 2011 to 2022,the national level of tourism development exhibited wave-like growth,while the overall level of green consumption remained stable.Significant regional disparities exist between the two,presenting a spatial pattern of“higher in the east and lower in the west.”(2)The coupling coordination degree between the two systems increased steadily from 0.562 to 0.604,reaching an overall coordinated state.A non-equilibrium pattern has emerged,characterized by“leading in the eastern region,catching up in the central region,improving in the western region,and under pressure in the northeastern region.”Inter-provincial differences remain evident but show signs of convergence.(3)Five major influencing factors-energy consumption,urbanization,population size,transportation infrastructure,and government regulation-exhibit significant spatiotemporal heterogeneity,with their effects showing clear regional adaptability in both magnitude and direction.Based on these findings,it is recommended to promote regionally differentiated development strategies,strengthen cross-provincial coordination mechanisms,and implement precise regulatory policies aligned with local development stages to foster high-level coordination between tourism development and green consumption.
文摘This paper investigated the analyses of removal of Methylene Blue (MB) and Brilliant Green (BG) dyes from aqueous solutions by adsorption on activated carbon prepared by chemical activation of coconut shell, eucalyptus tree, corn cob and flamboyant pod. It was found that the carbon pores increased after carbonization and activation processes. The maximum percentage MB removal was obtained as 95.0% for coconut shell, 93.2% for eucalyptus tree, 99.9% for corn cob, and 99.7% for flamboyant pod. Also, the maximum percentage BG removal was obtained as 97.0% for coconut shell, 98.2% for eucalyptus tree, 99.6% for corn cob, and 99.6% for flamboyant pod. The adsorption isotherms of the adsorption process were studied, and Freundlich model showed the best fit with the equilibrium data. To optimize the operating conditions, the effects of contact time, adsorbent dosage, and pH were investigated by two levels of factorial experimental design method and adsorbent dosage was found as the most significant factor.
基金supported by the“Second Tibetan Plateau Scientific Expedition and Research Program(STEP),Grant No.2019QZKK1007”from the Ministry of Science and Technology of China。
文摘A fundamental shift in the regional development pattern is crucial to achieving a comprehensive green transformation in China.Currently,innovation-driven green development is a significant strategic option for regional development.As the main body of innovation and the basic unit of regional composition,enterprises have a profound impact on the development of regional economy,society,ecology,and other aspects.However,considering China’s vast territory and significant regional differences in natural environment and industrial structure,it’s necessary to further explore the specific impact paths of regional green development driven by enterprise innovation.Therefore,taking industrial enterprises as an example,based on the panel data of 30 provinces in China from 2016 to 2020,this study verifies the impact of industrial enterprise innovation on the regional green development level by constructing a parallel multiple mediating effect model and dividing the economy into eastern,central,and western regions to discuss the specific impact paths.The results show that industrial enterprise innovation has a significant positive effect on regional green development level,via different influencing paths in each region:(1)The eastern region improves the regional green development level by narrowing the urban-rural income gap;(2)The central region improves the regional green development level by reducing resource dependence;and(3)The western region raises the regional green development level by improving the rationalization of industrial structure.
