In this paper,a novel contingency-aware method for N-2 security-constrained transmission expansion planning is proposed.To ensure that the transmission construction plan satisfies the N-2 security criterion,the propos...In this paper,a novel contingency-aware method for N-2 security-constrained transmission expansion planning is proposed.To ensure that the transmission construction plan satisfies the N-2 security criterion,the proposed method takes advantage of the adjustable robust optimization(ARO)framework and upgrades it.We construct a discrete uncertainty set in which component failures are treated as uncertain events that are handled as binary variables.In addition to the failure of existing lines and generators,we explicitly model the failure of candidate lines.The proposed model comprises a master problem that makes the transmission construction decision,and a series of subproblems that can detect not only the worst contingency,but also the potential contingencies.Computational studies on the IEEE RTS 24-bus and IEEE 118-bus test systems are carried out to validate the effectiveness of the proposed method.Compared with the deterministic method and ARO method in the literature,the proposed method has higher computational efficiency.展开更多
An optimization of device-to-device(D2D) security rate algorithm based on power control is provided to enhance the physical layer security underlaying D2D communication and guarantee the data rate requirement of the c...An optimization of device-to-device(D2D) security rate algorithm based on power control is provided to enhance the physical layer security underlaying D2D communication and guarantee the data rate requirement of the cellular user(CU) at the same time.First,a scenario model is set up,in which an eavesdropper is considered to wiretap the information of D2D transmitters.Then,a secure region of D2D communication is proposed.When D2D communication users reside outside the secure region,the spectrum of CU's is not allowed to share with the D2D communication so as to avoid eavesdropper tapping useful information of D2D communication.When D2D communication users reside inside the secure region,the security rate of D2D is maximized by optimization of the transmitting power of D2D and CU.The simulation results showthat the achieved D2D security rate of the proposed algorithm increases 2.8 bps/Hz when the signal to noise ratio(SNR) is 15 d B,compared with that when the random access algorithm is used.展开更多
A hierarchical peer-to-peer（P2P）model and a data fusion method for network security situation awareness system are proposed to improve the efficiency of distributed security behavior monitoring network.The single po...A hierarchical peer-to-peer（P2P）model and a data fusion method for network security situation awareness system are proposed to improve the efficiency of distributed security behavior monitoring network.The single point failure of data analysis nodes is avoided by this P2P model,in which a greedy data forwarding method based on node priority and link delay is devised to promote the efficiency of data analysis nodes.And the data fusion method based on repulsive theory-Dumpster/Shafer（PSORT-DS）is used to deal with the challenge of multi-source alarm information.This data fusion method debases the false alarm rate.Compared with improved Dumpster/Shafer（DS）theoretical method based on particle swarm optimization（PSO）and classical DS evidence theoretical method,the proposed model reduces false alarm rate by 3%and 7%,respectively,whereas their detection rate increases by 4%and 16%,respectively.展开更多
In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep le...In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep learning.Due to the mobility of users,using the current channel state information to select a transmit antenna or establish a D2D pair for the next time slot cannot ensure secure communication.Therefore,in this paper,we utilize the Echo State Network(ESN)to select the transmit antenna and the Long Short-Term Memory(LSTM)to establish the D2D pair.The simulation results show that the LSTMbased and ESN-based collaboration scheme can effectively improve the security capacity of the cellular network with D2D and increase the life of the base station.展开更多
The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneousl...The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.展开更多
Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping ene...Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping energy security has gained significant attention in recent years.Natural resources and geopolitical risk are examined in 38 countries at risk of geopolitical conflict between 1990 and 2021 by examining CO_(2) emissions,renewable energy consumption,and foreign direct investment as controlling variables.The long-run analysis conducted in this study focused on slope heterogeneity,Westerlund cointegration,and dynamic panel data estimation.The findings indicated that the energy security index is positively associated with various determinants,including natural resources,geopolitical risk,CO_(2) emissions,and renewable energy consumption.However,foreign direct investment was found to be negatively associated with the energy security index among the selected 38 geopolitical risk countries.The role of natural resources and geopolitical risk in energy security cannot be overlooked.Natural resources provide the raw materials for generating electricity and powering our societies,while geopolitical risks can disrupt energy supply chains and threaten stability.Achieving sustainable energy security requires a comprehensive approach that addresses both aspects of energy provision.Transitioning to renewable energy sources,improving energy efficiency,diversifying energy supplies,promoting international cooperation,and conserving natural resources are essential steps towards a more sustainable and resilient energy future.展开更多
More and more modern group oriented collaborativeapplications use the peer-to-peer(P2P)paradigm tobe independent of expensive infrastructures as theyare,for instance,provided for audio and video conferencesby H.323 sy...More and more modern group oriented collaborativeapplications use the peer-to-peer(P2P)paradigm tobe independent of expensive infrastructures as theyare,for instance,provided for audio and video conferencesby H.323 systems.Decentralized collaborativeP2P solutions require appropriate mechanismsto protect group privacy and data integrity.A centralizedclient/server based video conference system canbe well shielded in a standard manner,whilst thereare no off-the-shelf approaches to secure a P2P videoconference up to now.The paper addresses this issueand presents a flexible security architecture.Usingthe BRAVIS system[4]as an example it shows howthe architecture can be embedded into a P2P videoconferencing system.展开更多
基金supported by the National Key Research and Development Plan of China(No.2016YFB0900100)National Natural Science Foundation of China(No.51807116).
文摘In this paper,a novel contingency-aware method for N-2 security-constrained transmission expansion planning is proposed.To ensure that the transmission construction plan satisfies the N-2 security criterion,the proposed method takes advantage of the adjustable robust optimization(ARO)framework and upgrades it.We construct a discrete uncertainty set in which component failures are treated as uncertain events that are handled as binary variables.In addition to the failure of existing lines and generators,we explicitly model the failure of candidate lines.The proposed model comprises a master problem that makes the transmission construction decision,and a series of subproblems that can detect not only the worst contingency,but also the potential contingencies.Computational studies on the IEEE RTS 24-bus and IEEE 118-bus test systems are carried out to validate the effectiveness of the proposed method.Compared with the deterministic method and ARO method in the literature,the proposed method has higher computational efficiency.
基金National Natural Science Foundation of China(No.61503251)Natural Science Foundation of Shanghai,China(No.16ZR1424500)
文摘An optimization of device-to-device(D2D) security rate algorithm based on power control is provided to enhance the physical layer security underlaying D2D communication and guarantee the data rate requirement of the cellular user(CU) at the same time.First,a scenario model is set up,in which an eavesdropper is considered to wiretap the information of D2D transmitters.Then,a secure region of D2D communication is proposed.When D2D communication users reside outside the secure region,the spectrum of CU's is not allowed to share with the D2D communication so as to avoid eavesdropper tapping useful information of D2D communication.When D2D communication users reside inside the secure region,the security rate of D2D is maximized by optimization of the transmitting power of D2D and CU.The simulation results showthat the achieved D2D security rate of the proposed algorithm increases 2.8 bps/Hz when the signal to noise ratio(SNR) is 15 d B,compared with that when the random access algorithm is used.
基金Supported by the National Natural Science Foundation of China(61370212)the Research Fund for the Doctoral Program of Higher Education of China(20122304130002)+1 种基金the Natural Science Foundation of Heilongjiang Province(ZD 201102)the Fundamental Research Fund for the Central Universities(HEUCFZ1213,HEUCF100601)
文摘A hierarchical peer-to-peer（P2P）model and a data fusion method for network security situation awareness system are proposed to improve the efficiency of distributed security behavior monitoring network.The single point failure of data analysis nodes is avoided by this P2P model,in which a greedy data forwarding method based on node priority and link delay is devised to promote the efficiency of data analysis nodes.And the data fusion method based on repulsive theory-Dumpster/Shafer（PSORT-DS）is used to deal with the challenge of multi-source alarm information.This data fusion method debases the false alarm rate.Compared with improved Dumpster/Shafer（DS）theoretical method based on particle swarm optimization（PSO）and classical DS evidence theoretical method,the proposed model reduces false alarm rate by 3%and 7%,respectively,whereas their detection rate increases by 4%and 16%,respectively.
基金supported in part by the Aerospace Science and Technology Innovation Fund of China Aerospace Science and Technology Corporationin part by the Shanghai Aerospace Science and Technology Innovation Fund (No. SAST2018045, SAST2016034, SAST2017049)+1 种基金in part by the China Fundamental Research Fund for the Central Universities (No. 3102018QD096)in part by the Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University (No. ZZ2019024)
文摘In order to improve the physical layer security of the device-to-device(D2D)cellular network,we propose a collaborative scheme for the transmit antenna selection and the optimal D2D pair establishment based on deep learning.Due to the mobility of users,using the current channel state information to select a transmit antenna or establish a D2D pair for the next time slot cannot ensure secure communication.Therefore,in this paper,we utilize the Echo State Network(ESN)to select the transmit antenna and the Long Short-Term Memory(LSTM)to establish the D2D pair.The simulation results show that the LSTMbased and ESN-based collaboration scheme can effectively improve the security capacity of the cellular network with D2D and increase the life of the base station.
文摘The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.
基金funded by a grant from the Interdisciplinary Research Institute in New Finance and Economics,Hubei University of Economics(No.JXZD202403).
文摘Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping energy security has gained significant attention in recent years.Natural resources and geopolitical risk are examined in 38 countries at risk of geopolitical conflict between 1990 and 2021 by examining CO_(2) emissions,renewable energy consumption,and foreign direct investment as controlling variables.The long-run analysis conducted in this study focused on slope heterogeneity,Westerlund cointegration,and dynamic panel data estimation.The findings indicated that the energy security index is positively associated with various determinants,including natural resources,geopolitical risk,CO_(2) emissions,and renewable energy consumption.However,foreign direct investment was found to be negatively associated with the energy security index among the selected 38 geopolitical risk countries.The role of natural resources and geopolitical risk in energy security cannot be overlooked.Natural resources provide the raw materials for generating electricity and powering our societies,while geopolitical risks can disrupt energy supply chains and threaten stability.Achieving sustainable energy security requires a comprehensive approach that addresses both aspects of energy provision.Transitioning to renewable energy sources,improving energy efficiency,diversifying energy supplies,promoting international cooperation,and conserving natural resources are essential steps towards a more sustainable and resilient energy future.
文摘More and more modern group oriented collaborativeapplications use the peer-to-peer(P2P)paradigm tobe independent of expensive infrastructures as theyare,for instance,provided for audio and video conferencesby H.323 systems.Decentralized collaborativeP2P solutions require appropriate mechanismsto protect group privacy and data integrity.A centralizedclient/server based video conference system canbe well shielded in a standard manner,whilst thereare no off-the-shelf approaches to secure a P2P videoconference up to now.The paper addresses this issueand presents a flexible security architecture.Usingthe BRAVIS system[4]as an example it shows howthe architecture can be embedded into a P2P videoconferencing system.
