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In this paper, the problem of adaptive control is investigated for a class of non-strict feedback stochastic nonlinear systems with input delay. First, the effect of the input delay is eliminated by constructing an appropriate auxiliary system with the same order as the considered system. Then, with the help of the backstepping technique and the structural characteristics of the radial basis function (RBF) neural network (NN), an adaptive neural control scheme is extended to non-strict feedback stochastic nonlinear systems with input delay, in which uncertain nonlinear functions are approximated by RBF NN. Furthermore, the proposed adaptive controller ensures that all the closed-loop signals remain bounded in probability. Finally, two examples are provided to confirm the effectiveness of the designed strategy.

This study is concerned with the robust model predictive control (MPC) based on recurrent multi-dimensional Taylor network (RMTN) for the discrete-time non-linear time-delay systems. Regarding the MPC algorithm for the discrete-time time-delay systems, the existing literature only considers the linear case. In this study, by designing the suitable terminal cost and terminal region, the MPC scheme is firstly investigated for the non-linear case. Meanwhile, to reduce the computational burden of MPC using the existing model types (e.g. recurrent neural network) as the identified model, an RMTN possessing the concise structure and high computational efficiency is constructed to approximate the state-space model of the system. After trained by the backpropagation through time algorithm, the RMTN obtaining the high accuracy of prediction over a long-range horizon is capable of serving as the prediction model in the MPC scheme. Furthermore, aiming at alleviating the adverse effect of the inevitable identification error, the tube-based MPC is proposed via leveraging dual-mode MPC to guarantee that actual trajectory is contained within a robust tube. The stability of the considered system is proved theoretically, and numerical simulation is employed to validate the effectiveness of the proposed method.

A controlled quantum dialogue with authentication protocol on a basis of GHZ-like state was proposed in this paper. To start with, three participants of the communication protocol generated a corresponding identity ID through quantum key distribution and it was kept secret. Controller Trent prepared the three-particle Greenberger–Home–Zeilinger-like (GHZ-like) state and shared with other two communication users Alice and Bob. Communication participants use the entangled particles in their respective hands which satisfy the nature of the classical XOR relationship for encryption, controlling and decryption of quantum messages and to verify the identities of communication users. Meanwhile, security of communication was assured by introducing decoy photons. According to analysis results, the proposed protocol can effectively not only prevent any form of eavesdropping behavior from external and internal eavesdroppers including the controller Trent, but also detect such activities. Finally, this protocol is proved to have high communication efficiency.

A controlled quantum secure direct communication with authentication protocol based on the five-particle cluster state and the classical XOR operation is proposed in this paper. To begin with, three participants of the communication protocol generated a corresponding identity ID through quantum key distribution and kept it secret. The five-particle cluster state had two particles for the information frame, two for the identity and security check frame, and one for the control frame. According to a certain rule, the identity and security check was completed by using the z-base or x-base single-particle measurement. The sender Alice encoded the information by performing a unitary operation on the information particle sequence. With the controller’s help (Cindy), Bob decoded the information that Alice had sent by measuring the particle sequence and using the classical XOR operation according to certain rules. An analysis of the security of this protocol revealed that this protocol could effectively prevent eavesdroppers from acquiring useful information and was able to detect the eavesdropping behavior.

Quantum signature is a branch of quantum cryptography that draws on the design ideas of classic digital signatures, and uses the basic principles of quantum mechanics to achieve the integrity, authenticity and nonrepudiation of quantum information. Among them, arbitration quantum signature (AQS) plays a very important role. In this paper, we proposed an AQS protocol based on XOR encryption. Unlike other protocols, a quantum one-time pad encryption method or chain-type CNOT encryption method is abandoned. The proposed protocol is designed based on the three-particle GHZ state combined with the idea of classical XOR encryption, with CNOT operations used to encrypt quantum messages and quantum signatures. A security analysis of the proposed protocol reveals that the proposed protocol can satisfy the AQS requirements of unforgeability and nonrepudiation.

Contraposed the reality of great market demand of energy-saving lamp, and its middle-high grade trends in production etc., the design of a high-performance production line control system of energy-saving lamp based on HMI and 485 network communication has the characteristics of good reliability, high efficiency and convenient operation. The production line control system is operated through human-machine interface, using RS-485 bus for message communication, has a lower cost and a good prospect.