In this paper, during the masking process the encrypted message is convolved and embedded into a Qi hyper-chaotic system characterizing a high disorder degree. The masking scheme was tested using both Qi hyper-chaos a...In this paper, during the masking process the encrypted message is convolved and embedded into a Qi hyper-chaotic system characterizing a high disorder degree. The masking scheme was tested using both Qi hyper-chaos and Lorenz chaos and indicated that Qi hyper-chaos based masking can resist attacks of the filtering and power spectrum analysis, while the Lorenz based scheme fails for high amplitude data. To unmask the message at the receiving end, two methods are proposed. In the first method, a model-free synchronizer, i.e. a multivariable higher-order differential feedback controller between the transmitter and receiver is employed to de-convolve the message embedded in the receiving signal. In the second method, no synchronization is required since the message is de-convolved using the information of the estimated derivative.展开更多
This paper proposes a model-based reference tracking scheme for stable,MIMO,nonlinear processes.A Joint Unscented Kalman Filtering technique is exploited here to develop a stochastic model of the physical process via ...This paper proposes a model-based reference tracking scheme for stable,MIMO,nonlinear processes.A Joint Unscented Kalman Filtering technique is exploited here to develop a stochastic model of the physical process via simultaneous estimation of the process states and the time-varying/uncertain parameters.Unlike the existing nonlinear model predictive controllers,the proposed scheme does not involve any dynamic optimisation process,which helps to reduce the overall complexity,computation overburden and execution time.Furthermore,the proposed methodology offers robustness to process model-mismatch and considers the effects of stochastic disturbances.A nonlinear two-tank liquid-level control problem and a nonlinear coupled level-temperature control process are studied to demonstrate the usefulness of the proposed scheme.展开更多
基金Project supported by the Incentive Funding National Research Foundation of South Africa(Grant No.70722)the Eskom Tertiary Education Support Programme of South Africa
文摘In this paper, during the masking process the encrypted message is convolved and embedded into a Qi hyper-chaotic system characterizing a high disorder degree. The masking scheme was tested using both Qi hyper-chaos and Lorenz chaos and indicated that Qi hyper-chaos based masking can resist attacks of the filtering and power spectrum analysis, while the Lorenz based scheme fails for high amplitude data. To unmask the message at the receiving end, two methods are proposed. In the first method, a model-free synchronizer, i.e. a multivariable higher-order differential feedback controller between the transmitter and receiver is employed to de-convolve the message embedded in the receiving signal. In the second method, no synchronization is required since the message is de-convolved using the information of the estimated derivative.
基金supported by the Science and Engineering Research Board(SERB),DST,India[grant number SRG/2022/000892].
文摘This paper proposes a model-based reference tracking scheme for stable,MIMO,nonlinear processes.A Joint Unscented Kalman Filtering technique is exploited here to develop a stochastic model of the physical process via simultaneous estimation of the process states and the time-varying/uncertain parameters.Unlike the existing nonlinear model predictive controllers,the proposed scheme does not involve any dynamic optimisation process,which helps to reduce the overall complexity,computation overburden and execution time.Furthermore,the proposed methodology offers robustness to process model-mismatch and considers the effects of stochastic disturbances.A nonlinear two-tank liquid-level control problem and a nonlinear coupled level-temperature control process are studied to demonstrate the usefulness of the proposed scheme.
