Based on the characteristics of ATM system and the special requirement of financial transaction, an overall design of hardware and software structure of ATM was made. For software structure, the pattern of modules and...Based on the characteristics of ATM system and the special requirement of financial transaction, an overall design of hardware and software structure of ATM was made. For software structure, the pattern of modules and table? drive is adopted to realize the security of financial transaction and the diagnosis of communication fault. A new method, which is based on the application layer, transport layer and network layer, is used for diagnosing communication fault. Supporting both magnetic card and IC card, the system has been put into use in real financial systems, and has brought about both economic and social effects.展开更多
In spectrum aggregation(SA), two or more component carriers(CCs) of different bandwidths in different bands can be aggregated to support wider transmission bandwidth. The current resource scheduling schemes for spectr...In spectrum aggregation(SA), two or more component carriers(CCs) of different bandwidths in different bands can be aggregated to support wider transmission bandwidth. The current resource scheduling schemes for spectrum aggregation are not optimal or suitable for CR based heterogeneous networks(Het Nets). Consequently, the authors propose a novel resource scheduling scheme for spectrum aggregation in CR based Het Nets, termed as cognitive radio based resource scheduling(CR-RS) scheme. CR-RS has a three-level structure. Under a dynamic traffic model, an equivalent throughput of the CCs based on the knowledge of primary users(PUs) is given. On this basis, the CR users data transmission time of each CC is equal in CR-RS. The simulation results show that CR-RS has the better performance than the current resource scheduling schemes in the CR based Het Nets. Meanwhile, CR-RS is also effective in other spectrum aggregation systems which are not CR based HetNets.展开更多
Motivated by the objective of pursuing revenue, improvement in coverage and reduction in energy cost for wireless communication networks have been of great significance for mobile operators. Therefore, heterogeneous c...Motivated by the objective of pursuing revenue, improvement in coverage and reduction in energy cost for wireless communication networks have been of great significance for mobile operators. Therefore, heterogeneous cellular networks(HCNs) and Coordinated Multipoint(Co MP) transmission are considered as promising solutions to enhance the performances of wireless communication systems. This paper analyzed the K-tier HCNs with a dynamic downlink Co MP scheme, in which the flexible clusters of cooperative stations are determined by a connecting threshold θ. Using stochastic geometry, the coverage probability(CP) and energy efficiency(EE) of a K-tier HCN operating under this scheme are derived, based on which the trade-off between CP and EE is discovered and discussed. Simulation results show the validity of our derivations. The proposed schememay significantly reduce energy consumption sacrificing a small amount of CP, and outperforms the fixed scheme as well. The CP-EE trade-off are also revealed, whichsuggests suitable trade-off points between CP and EE that will deliver the maximum economic profitability. Tendencies discovered in this paper may provide the operators with opportunities for further optimization in pursuit of economic profitability.展开更多
Rationally designed heterostructures provide attractive prospects for energy storage electrodes by combining different active materials with distinct electrochemical properties.Herein,through a phase separation strate...Rationally designed heterostructures provide attractive prospects for energy storage electrodes by combining different active materials with distinct electrochemical properties.Herein,through a phase separation strategy,a heterostructure of SnO_(2) encapsulated by amorphous Nb_(2)O_(5) is spontaneously synthesized.Insertion-type anode Nb_(2)O_(5) outer shell,playing as reaction containers and fast ionic pathways,physically inhibits the Sn atoms’migration and enhances the reaction kinetics.Moreover,strong chemical interactions are found at the SnO_(2)/Nb_(2)O_(5) interfaces,which ensure the solid encapsulation of the SnO_(2) cores even after 500 cycles.When used for lithium-ion batteries,this heterostructured anode exhibits high cycling stability with a capacity of 626 mAhg^(-1) after 1000 cycles at 2Ag^(-1)(85% capacity retention)and good rate performance with the capacity of 340 mAhg^(-1) at 8Ag^(-1).展开更多
文摘Based on the characteristics of ATM system and the special requirement of financial transaction, an overall design of hardware and software structure of ATM was made. For software structure, the pattern of modules and table? drive is adopted to realize the security of financial transaction and the diagnosis of communication fault. A new method, which is based on the application layer, transport layer and network layer, is used for diagnosing communication fault. Supporting both magnetic card and IC card, the system has been put into use in real financial systems, and has brought about both economic and social effects.
基金supported by Major National Science and Technology Project(2014ZX03004003-005)Municipal Exceptional Academic Leaders Foundation (2014RFXXJ002)China Postdoctoral Science Foundation (2014M561347)
文摘In spectrum aggregation(SA), two or more component carriers(CCs) of different bandwidths in different bands can be aggregated to support wider transmission bandwidth. The current resource scheduling schemes for spectrum aggregation are not optimal or suitable for CR based heterogeneous networks(Het Nets). Consequently, the authors propose a novel resource scheduling scheme for spectrum aggregation in CR based Het Nets, termed as cognitive radio based resource scheduling(CR-RS) scheme. CR-RS has a three-level structure. Under a dynamic traffic model, an equivalent throughput of the CCs based on the knowledge of primary users(PUs) is given. On this basis, the CR users data transmission time of each CC is equal in CR-RS. The simulation results show that CR-RS has the better performance than the current resource scheduling schemes in the CR based Het Nets. Meanwhile, CR-RS is also effective in other spectrum aggregation systems which are not CR based HetNets.
基金supported by the National Natural Science Foundation of China under Grant No.61231009the National High-tech Research and Development Program of China under Grant No.2014AA01A701the Program for New Century Excellent Talents in University of Ministry of Education of China under Grant No.NCET 12-0795
文摘Motivated by the objective of pursuing revenue, improvement in coverage and reduction in energy cost for wireless communication networks have been of great significance for mobile operators. Therefore, heterogeneous cellular networks(HCNs) and Coordinated Multipoint(Co MP) transmission are considered as promising solutions to enhance the performances of wireless communication systems. This paper analyzed the K-tier HCNs with a dynamic downlink Co MP scheme, in which the flexible clusters of cooperative stations are determined by a connecting threshold θ. Using stochastic geometry, the coverage probability(CP) and energy efficiency(EE) of a K-tier HCN operating under this scheme are derived, based on which the trade-off between CP and EE is discovered and discussed. Simulation results show the validity of our derivations. The proposed schememay significantly reduce energy consumption sacrificing a small amount of CP, and outperforms the fixed scheme as well. The CP-EE trade-off are also revealed, whichsuggests suitable trade-off points between CP and EE that will deliver the maximum economic profitability. Tendencies discovered in this paper may provide the operators with opportunities for further optimization in pursuit of economic profitability.
基金supported by China Postdoctoral Science Foundation(2020M671242 and 2021T140688)the Special Research Assistant program of CASthe Super Postdoctoral Fellow Program of Shanghai。
文摘Rationally designed heterostructures provide attractive prospects for energy storage electrodes by combining different active materials with distinct electrochemical properties.Herein,through a phase separation strategy,a heterostructure of SnO_(2) encapsulated by amorphous Nb_(2)O_(5) is spontaneously synthesized.Insertion-type anode Nb_(2)O_(5) outer shell,playing as reaction containers and fast ionic pathways,physically inhibits the Sn atoms’migration and enhances the reaction kinetics.Moreover,strong chemical interactions are found at the SnO_(2)/Nb_(2)O_(5) interfaces,which ensure the solid encapsulation of the SnO_(2) cores even after 500 cycles.When used for lithium-ion batteries,this heterostructured anode exhibits high cycling stability with a capacity of 626 mAhg^(-1) after 1000 cycles at 2Ag^(-1)(85% capacity retention)and good rate performance with the capacity of 340 mAhg^(-1) at 8Ag^(-1).
