The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random k...The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random keys for OTP.In this paper,we propose a joint SKG and OTP encryption scheme with the aid of a reconfigurable intelligent surface(RIS)to boost secret key rate.To maximize the efficiency of secure communication,we divide the process of secure transmission into two stages:SKG and then encrypted packet transmission.Meanwhile,we design an optimal algorithm for allocating time slots for SKG to maximize SKG efficiency without security risk.Furthermore,we design a key updating protocol based on our SKG scheme for OTP encryption.Simulation results verify that our scheme can generate keys securely and efficiently,and significantly improve the secure communication performance in an intelligent IoT system.展开更多
To investigate the effect of rail pad viscoelasticity on vehicle-track-bridge coupled vibration,the fractional Voigt and Maxwell model in parallel(FVMP)was used to characterize the viscoelastic properties of the rail ...To investigate the effect of rail pad viscoelasticity on vehicle-track-bridge coupled vibration,the fractional Voigt and Maxwell model in parallel(FVMP)was used to characterize the viscoelastic properties of the rail pad based on dynamic performance test results.The FVMP model was then incorporated into the vehicle-track-bridge nonlinear coupled model,and its dynamic response was solved using a cross-iteration algorithm with a relaxation factor.Results indicate that the nonlinear coupled model achieves good convergence when the time step is less than 0.001 s,with the cross-iteration algorithm adjusting the wheel-rail force.In particular,the best convergence is achieved when the relaxation factor is within the range of 0.3-0.5.The FVMP model effectively characterizes the viscoelasticity of rail pads across a temperature range of±20℃and a frequency range of 1-1000 Hz.The viscoelasticity of rail pads significantly affects high-frequency vibrations in the coupled system,particularly around 50 Hz,corresponding to the wheel-rail coupled resonance range.Considering rail pad viscoelasticity is essential for accurately predicting track structure vibrations.展开更多
Although the encryption of network packets significantly increases privacy, the density of the traffic can still provide useful information to the observer, and maybe results in the breach of confidentiality. In this ...Although the encryption of network packets significantly increases privacy, the density of the traffic can still provide useful information to the observer, and maybe results in the breach of confidentiality. In this paper, we address issues related to hiding information in self-similar network, which is proved to be similar with modern communication network. And a statistical hiding algorithm is proposed for traffic padding. The figures and the comparison of Hurst Parameters before and after traffic padding, show the effective performance of the algorithm.展开更多
A recursive rational algorithm for matrix exponentials was obtained by making use of the generalized inverse of a matrix in this paper. On the basis of the n th convergence of Thiele type continued fraction expa...A recursive rational algorithm for matrix exponentials was obtained by making use of the generalized inverse of a matrix in this paper. On the basis of the n th convergence of Thiele type continued fraction expansion, a new type of the generalized inverse matrix valued Padé approximant (GMPA) for matrix exponentials was defined and its remainder formula was proved. The results of this paper were illustrated by some examples.展开更多
In this paper, Homotopy Analysis method with Genetic Algorithm is presented and used to obtain an analytical solution for the time-dependent Emden-Fowler type of equations and wave-type equation with singular behavior...In this paper, Homotopy Analysis method with Genetic Algorithm is presented and used to obtain an analytical solution for the time-dependent Emden-Fowler type of equations and wave-type equation with singular behavior at x = 0. The advantage of this single global method employed to present a reliable framework is utilized to overcome the singularity behavior at the point x = 0 for both models. The method is demonstrated for a variety of problems in one and higher dimensional spaces where approximate-exact solutions are obtained. The results obtained in all cases show the reliability and the efficiency of this method.展开更多
We present two robust quantum secure direct communication (QSDC) schemes with a quantum one-time pad over a collective-noise channel. Each logical qubit is made up of two physical qubits and it is invariant over a col...We present two robust quantum secure direct communication (QSDC) schemes with a quantum one-time pad over a collective-noise channel. Each logical qubit is made up of two physical qubits and it is invariant over a collective-noise channel. The two photons in each logical qubit can be produced with a practically entangled source, i.e., a parametric down-conversion source with a beta barium borate crystal and a pump pulse of ultraviolet light. The information is encoded on each logical qubit with two logical unitary operations, which will not destroy the antinoise feather of the quantum systems. The receiver Bob can read out the sender's message directly with two single-photon measurements on each logical qubit, instead of Bell-state measurements, which will make these protocols more convenient in a practical application. With current technology, our two robust QSDC schemes are feasible and may be optimal ones.展开更多
Due to the broadcast nature of wireless channels and the development of quantum computers,the confidentiality of wireless communication is seriously threatened.In this paper,we propose an integrated communications and...Due to the broadcast nature of wireless channels and the development of quantum computers,the confidentiality of wireless communication is seriously threatened.In this paper,we propose an integrated communications and security(ICAS)design to enhance communication security using reconfigurable intelligent surfaces(RIS),in which the physical layer key generation(PLKG)rate and the data transmission rate are jointly considered.Specifically,to deal with the threat of eavesdropping attackers,we focus on studying the simultaneous transmission and key generation(STAG)by configuring the RIS phase shift.Firstly,we derive the key generation rate of the RIS assisted PLKG and formulate the optimization problem.Then,in light of the dynamic wireless environments,the optimization problem is modeled as a finite Markov decision process.We put forward a policy gradient-based proximal policy optimization(PPO)algorithm to optimize the continuous phase shift of the RIS,which improves the convergence stability and explores the security boundary of the RIS phase shift for STAG.The simulation results demonstrate that the proposed algorithm outperforms the benchmark method in convergence stability and system performance.By reasonably allocating the weight factors for the data transmission rate and the key generation rate,“one-time pad”communication can be achieved.The proposed method has about 90%performance improvement for“one-time pad”communication compared with the benchmark methods.展开更多
基金supported by National key research and development program of China, Joint research of IoT security system and key technologies based on quantum key (2020YFE0200600)
文摘The one-time pad(OTP)is an applicationlayer encryption technique to achieve the informationtheoretic security,and the physical-layer secret key generation(SKG)technique is a promising candidate to provide the random keys for OTP.In this paper,we propose a joint SKG and OTP encryption scheme with the aid of a reconfigurable intelligent surface(RIS)to boost secret key rate.To maximize the efficiency of secure communication,we divide the process of secure transmission into two stages:SKG and then encrypted packet transmission.Meanwhile,we design an optimal algorithm for allocating time slots for SKG to maximize SKG efficiency without security risk.Furthermore,we design a key updating protocol based on our SKG scheme for OTP encryption.Simulation results verify that our scheme can generate keys securely and efficiently,and significantly improve the secure communication performance in an intelligent IoT system.
基金Project(2023ZDZX0008)supported by the Sichuan Major Science and Technology Project,ChinaProject(52308468)supported by the National Natural Science Foundation of ChinaProject(2022JBQY009)supported by the Fundamental Research Funds for the Central Universities(Science and Technology Leading Talent Team Project),China。
文摘To investigate the effect of rail pad viscoelasticity on vehicle-track-bridge coupled vibration,the fractional Voigt and Maxwell model in parallel(FVMP)was used to characterize the viscoelastic properties of the rail pad based on dynamic performance test results.The FVMP model was then incorporated into the vehicle-track-bridge nonlinear coupled model,and its dynamic response was solved using a cross-iteration algorithm with a relaxation factor.Results indicate that the nonlinear coupled model achieves good convergence when the time step is less than 0.001 s,with the cross-iteration algorithm adjusting the wheel-rail force.In particular,the best convergence is achieved when the relaxation factor is within the range of 0.3-0.5.The FVMP model effectively characterizes the viscoelasticity of rail pads across a temperature range of±20℃and a frequency range of 1-1000 Hz.The viscoelasticity of rail pads significantly affects high-frequency vibrations in the coupled system,particularly around 50 Hz,corresponding to the wheel-rail coupled resonance range.Considering rail pad viscoelasticity is essential for accurately predicting track structure vibrations.
基金Sponsored by the Program for New Excellent Talents in University(Grant No.NZCT2004-0332)
文摘Although the encryption of network packets significantly increases privacy, the density of the traffic can still provide useful information to the observer, and maybe results in the breach of confidentiality. In this paper, we address issues related to hiding information in self-similar network, which is proved to be similar with modern communication network. And a statistical hiding algorithm is proposed for traffic padding. The figures and the comparison of Hurst Parameters before and after traffic padding, show the effective performance of the algorithm.
文摘A recursive rational algorithm for matrix exponentials was obtained by making use of the generalized inverse of a matrix in this paper. On the basis of the n th convergence of Thiele type continued fraction expansion, a new type of the generalized inverse matrix valued Padé approximant (GMPA) for matrix exponentials was defined and its remainder formula was proved. The results of this paper were illustrated by some examples.
文摘In this paper, Homotopy Analysis method with Genetic Algorithm is presented and used to obtain an analytical solution for the time-dependent Emden-Fowler type of equations and wave-type equation with singular behavior at x = 0. The advantage of this single global method employed to present a reliable framework is utilized to overcome the singularity behavior at the point x = 0 for both models. The method is demonstrated for a variety of problems in one and higher dimensional spaces where approximate-exact solutions are obtained. The results obtained in all cases show the reliability and the efficiency of this method.
基金supported by the Natural Science Foundation of Jiangsu Provincial Universities (Grant No. 10KJB180004)the National Natural Science Foundation of China (Grant No. 10847147)
文摘We present two robust quantum secure direct communication (QSDC) schemes with a quantum one-time pad over a collective-noise channel. Each logical qubit is made up of two physical qubits and it is invariant over a collective-noise channel. The two photons in each logical qubit can be produced with a practically entangled source, i.e., a parametric down-conversion source with a beta barium borate crystal and a pump pulse of ultraviolet light. The information is encoded on each logical qubit with two logical unitary operations, which will not destroy the antinoise feather of the quantum systems. The receiver Bob can read out the sender's message directly with two single-photon measurements on each logical qubit, instead of Bell-state measurements, which will make these protocols more convenient in a practical application. With current technology, our two robust QSDC schemes are feasible and may be optimal ones.
基金supported in part by the National Science Foundation of China(NSFC)under Grant No.62371131in part by the National Key R&D Program of China under Grant No.2024YFE0200700in part by the program of Zhishan Young Scholar of Southeast University under Grant No.2242024RCB0030。
文摘Due to the broadcast nature of wireless channels and the development of quantum computers,the confidentiality of wireless communication is seriously threatened.In this paper,we propose an integrated communications and security(ICAS)design to enhance communication security using reconfigurable intelligent surfaces(RIS),in which the physical layer key generation(PLKG)rate and the data transmission rate are jointly considered.Specifically,to deal with the threat of eavesdropping attackers,we focus on studying the simultaneous transmission and key generation(STAG)by configuring the RIS phase shift.Firstly,we derive the key generation rate of the RIS assisted PLKG and formulate the optimization problem.Then,in light of the dynamic wireless environments,the optimization problem is modeled as a finite Markov decision process.We put forward a policy gradient-based proximal policy optimization(PPO)algorithm to optimize the continuous phase shift of the RIS,which improves the convergence stability and explores the security boundary of the RIS phase shift for STAG.The simulation results demonstrate that the proposed algorithm outperforms the benchmark method in convergence stability and system performance.By reasonably allocating the weight factors for the data transmission rate and the key generation rate,“one-time pad”communication can be achieved.The proposed method has about 90%performance improvement for“one-time pad”communication compared with the benchmark methods.