This paper investigates secure transmission for non-orthogonal multiple access(NOMA)systems where the imperfect successive interference cancellation(SIC)is considered at both legitimate users and eavesdropper(Eve).A p...This paper investigates secure transmission for non-orthogonal multiple access(NOMA)systems where the imperfect successive interference cancellation(SIC)is considered at both legitimate users and eavesdropper(Eve).A power allocation scheme is designed for the legitimate users to mitigate the effect of the SIC error caused by imperfect SIC.For characterizing the secrecy performance of the NOMA system,the closed-form expressions for connection outage probability(COP),secrecy outage probability(SOP),and effective secrecy throughput(EST)are derived over Nakagami-m fading channels in both NOMA and benchmark orthogonal multiple access(OMA)systems.We also provide security and reliability trade-off results(SRT)for the users in the NOMA and OMA systems.Simulation results verify our analysis and show that the strong users achieve better secrecy performance but worse reliability performance and NOMA outperforms OMA in terms of SRT.展开更多
Among various power system disturbances,cascading failures are considered the most serious and extreme threats to grid operations,potentially leading to significant stability issues or even widespread power blackouts....Among various power system disturbances,cascading failures are considered the most serious and extreme threats to grid operations,potentially leading to significant stability issues or even widespread power blackouts.Simulating power systems’behaviors during cascading failures is of great importance to comprehend how failures originate and propagate,as well as to develop effective preventive and mitigative control strategies.The intricate mechanism of cascading failures,characterized by multi-timescale dynamics,presents exceptional challenges for their simulations.This paper provides a comprehensive review of simulation models for cascading failures,providing a systematic categorization and a comparison of these models.The challenges and potential research directions for the future are also discussed.展开更多
基金supported by the National Key R&D Program of China(No.2018YFB1801103)the National Natural Science Foundation of China(No.61771487).
文摘This paper investigates secure transmission for non-orthogonal multiple access(NOMA)systems where the imperfect successive interference cancellation(SIC)is considered at both legitimate users and eavesdropper(Eve).A power allocation scheme is designed for the legitimate users to mitigate the effect of the SIC error caused by imperfect SIC.For characterizing the secrecy performance of the NOMA system,the closed-form expressions for connection outage probability(COP),secrecy outage probability(SOP),and effective secrecy throughput(EST)are derived over Nakagami-m fading channels in both NOMA and benchmark orthogonal multiple access(OMA)systems.We also provide security and reliability trade-off results(SRT)for the users in the NOMA and OMA systems.Simulation results verify our analysis and show that the strong users achieve better secrecy performance but worse reliability performance and NOMA outperforms OMA in terms of SRT.
基金supported by UT-Battelle,LLC under Contract No.DE-AC05-00OR22725 with the U.S.Department of Energy.
文摘Among various power system disturbances,cascading failures are considered the most serious and extreme threats to grid operations,potentially leading to significant stability issues or even widespread power blackouts.Simulating power systems’behaviors during cascading failures is of great importance to comprehend how failures originate and propagate,as well as to develop effective preventive and mitigative control strategies.The intricate mechanism of cascading failures,characterized by multi-timescale dynamics,presents exceptional challenges for their simulations.This paper provides a comprehensive review of simulation models for cascading failures,providing a systematic categorization and a comparison of these models.The challenges and potential research directions for the future are also discussed.
