Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accid...Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is "chronic" and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.展开更多
This paper proposes a multi-layer multi-agent model for the performance evaluation of powersystems,which is different from the existing multi-agent ones.To describe the impact of the structureof the networked power sy...This paper proposes a multi-layer multi-agent model for the performance evaluation of powersystems,which is different from the existing multi-agent ones.To describe the impact of the structureof the networked power system,the proposed model consists of three kinds of agents that form threelayers:control agents such as the generators and associated controllers,information agents to exchangethe information based on the wide area measurement system (WAMS) or transmit control signals tothe power system stabilizers (PSSs),and network-node agents such as the generation nodes and loadnodes connected with transmission lines.An optimal index is presented to evaluate the performance ofdamping controllers to the system's inter-area oscillation with respect to the information-layer topology.Then,the authors show that the inter-area information exchange is more powerful than the exchangewithin a given area to control the inter-area low frequency oscillation based on simulation analysis.展开更多
文摘Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is "chronic" and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.
基金supported in part by the National Natural Science Foundation of China under Grants Nos. 50707035, 50595411, 60425307, 60221301 and 50607005, in part by the 111 project (B08013)Program for Changjiang Scholars and Innovative Research Team in University (IRT0515)in part by the Program for New Century Excellent Talents in University (NCET-05-0216)
文摘This paper proposes a multi-layer multi-agent model for the performance evaluation of powersystems,which is different from the existing multi-agent ones.To describe the impact of the structureof the networked power system,the proposed model consists of three kinds of agents that form threelayers:control agents such as the generators and associated controllers,information agents to exchangethe information based on the wide area measurement system (WAMS) or transmit control signals tothe power system stabilizers (PSSs),and network-node agents such as the generation nodes and loadnodes connected with transmission lines.An optimal index is presented to evaluate the performance ofdamping controllers to the system's inter-area oscillation with respect to the information-layer topology.Then,the authors show that the inter-area information exchange is more powerful than the exchangewithin a given area to control the inter-area low frequency oscillation based on simulation analysis.