The current healthcare system in Hong Kong is experiencing pressure due to constrained resources,with dramatic increases in inpatient services queue lengths,dissatisfaction with the working environment,unacceptable wo...The current healthcare system in Hong Kong is experiencing pressure due to constrained resources,with dramatic increases in inpatient services queue lengths,dissatisfaction with the working environment,unacceptable workforce arrangements and high turnover rate of hospital staff.To maintain the robustness of the healthcare system and a sustainable inpatients flow,the Food and Health Bureau launched a public-private partnership programme to utilise the resources of the public and private hospitals.This research investigates the potential for extension of the programme and further enhancing the sustainability of the long-term inpatient services under a mixed public-private healthcare policy via system dynamic modelling.The findings show that an increase of human resources in public hospitals does not substantially improve inpatient flow rate performance.Further,the results from the system dynamic approach provide insights into the expansion of the service areas of the programme and suggest increasing the number of referrals to private hospitals.展开更多
Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the...Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins.展开更多
Effective thermal control systems are essential for reliable operation of spacecraft.A dual-driven intelligent combination control strategy is proposed to improve the temperate control and heat flux tracking effects.B...Effective thermal control systems are essential for reliable operation of spacecraft.A dual-driven intelligent combination control strategy is proposed to improve the temperate control and heat flux tracking effects.Both temperature regulation and heat flux tracking errors are employed to generate the final control action;their contributions are adaptively adjusted by a fuzzy fusing policy of control actions.To evaluate the control effects,describe a four-nodal mathematical model for analyzing the dynamic characteristics of the controlled heat pipe space cooling system(HP-SCS) consisting of an aluminum-ammonia heat pipe and a variable-emittance micro-electromechanical-system(MEMS) radiator.This dynamical model calculates the mass flow-rate and condensing pressure of the heat pipe working fluid directly from the systemic nodal temperatures,therefore,it is more suitable for control engineering applications.The closed-loop transient performances of four different control schemes have been numerically investigated.The results conclude that the proposed intelligent combination control scheme not only improves the thermal control effects but also benefits the safe operation of HP-SCS.展开更多
基金Research Committee and the Department of Industrial and Systems Engineering of the Hong Kong Polytechnic University for supporting this project(G-UA7X).
文摘The current healthcare system in Hong Kong is experiencing pressure due to constrained resources,with dramatic increases in inpatient services queue lengths,dissatisfaction with the working environment,unacceptable workforce arrangements and high turnover rate of hospital staff.To maintain the robustness of the healthcare system and a sustainable inpatients flow,the Food and Health Bureau launched a public-private partnership programme to utilise the resources of the public and private hospitals.This research investigates the potential for extension of the programme and further enhancing the sustainability of the long-term inpatient services under a mixed public-private healthcare policy via system dynamic modelling.The findings show that an increase of human resources in public hospitals does not substantially improve inpatient flow rate performance.Further,the results from the system dynamic approach provide insights into the expansion of the service areas of the programme and suggest increasing the number of referrals to private hospitals.
基金Key Project of National Natural Science Foundation of China, No.40335049 National Natural Science Foundation of China, No.40471059
文摘Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins.
基金National Natural Science Foundation of China(50506003)
文摘Effective thermal control systems are essential for reliable operation of spacecraft.A dual-driven intelligent combination control strategy is proposed to improve the temperate control and heat flux tracking effects.Both temperature regulation and heat flux tracking errors are employed to generate the final control action;their contributions are adaptively adjusted by a fuzzy fusing policy of control actions.To evaluate the control effects,describe a four-nodal mathematical model for analyzing the dynamic characteristics of the controlled heat pipe space cooling system(HP-SCS) consisting of an aluminum-ammonia heat pipe and a variable-emittance micro-electromechanical-system(MEMS) radiator.This dynamical model calculates the mass flow-rate and condensing pressure of the heat pipe working fluid directly from the systemic nodal temperatures,therefore,it is more suitable for control engineering applications.The closed-loop transient performances of four different control schemes have been numerically investigated.The results conclude that the proposed intelligent combination control scheme not only improves the thermal control effects but also benefits the safe operation of HP-SCS.