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Abstract This paper is concerned with tele‐presence and tele‐operation of autonomous vehicles over the Additive White Gaussian Noise (AWGN) channel. This wireless communication channel is subject to transmission noise and transmission power constraint. An encoder, decoder and controller are proposed by implementing a novel linearization method for linearizing the nonlinear dynamic systems at operating points. For the linearized systems, the encoder, decoder and controller are implemented that were previously proposed for output tracking as well as stability of linear dynamic systems. Two novel linearization methods are proposed and their satisfactory performances are proved for output tracking as well as stability of nonlinear dynamic system. The first method is based on the fixed linearization rate and the second one is based on the variable (optimal) linearization rate. The decoder that is based on the second method is in fact the extended Kalman filter with the optimal linearization rate. The performances of these two methods are compared with each other and the other proposed methods by implementing them to the problems of the tele‐presence and tele‐operation of autonomous vehicles over the AWGN channel. Their satisfactory performances are illustrated. It is illustrated that the second method has higher computational complexity with slightly better performance and is applicable to a larger class of reference trajectories.

Abstract Non‐linearity is an inherent feature of practical systems. Although there have been significant advances in the control of nonlinear systems, the proposed methods often require considerable computational resources or rely on local linearization around equilibrium points. The Koopman operator is an infinite‐dimensional linear operator that fully captures a system's non‐linear dynamics. However, one of the major problems is identifying a Koopman finite dimensional linear model for a nonlinear system. Initiated by the Willems’ fundamental Lemma, a class of data‐driven control methods has been developed for linear systems without the need to identify the system's matrices. Motivated by these two ideas, a data‐driven Koopman‐based predictive control scheme for non‐linear systems is proposed for unknown disturbed non‐linear systems utilising a finite‐length dataset. Then, considering the uncertainty in the Koopman state variables, a robust data‐driven Koopman predictive control structure is presented. Also, the results led to the design of a data‐driven Koopman predictive control strategy with terminal components to ensure the closed‐loop stability of nonlinear systems. The proposed scheme is tested on the distributed‐parameter model of the ACUREX solar collector field (located at Almería, Spain) to regulate the field outlet temperature around a desired value. Finally, simulation results show the effectiveness of the proposed approach.

According to psychologists and researchers, many people go through five psychological stages when they experience new feelings and conditions after losing a loved one. Among those five stages is "anger." At this stage, the mourner angrily tries to find the answers to questions that have arisen for him after losing his loved one. Since he doesn't view himself as deserving of such suffering, he asks himself and others why God took his beloved from him? Why did He make life bitter for him? And so on. In the stage of anger, a person's mental state and the questions that are raised from it challenge his relationship with God. Philosophers of religion have also addressed this problem. According to a classical division, philosophers of religion study the problem of evil in two areas: theoretical and existential. Mourners' questions and their suffering -which appeared as an exaggerated evil- are related to the existential problem of evil. In this area, individuals are faced with situations that reinforce their doubt or disbelief in the existence of God. Philosophers such as Alvin Plantinga argue that philosophical debates about the existential realm of evil are not fruitful, but that spiritual care should be practiced instead. It is in this context that pastoral theology in Christianity is a widely debated topic. It seems that remembrance of the sufferings and calamities that happened in the lives of divine saints can guide the mourner's attitude. In other words, by reflecting on these recollections, he can find meaning for their mourning and get over their grief more easily. The sufferings of Hussein ibn Ali (as) in the story of Ashura can be recalled for this purpose. In Shia practice, there seems to be evidence for this view of Ashura.

This paper addresses the leader–follower consensus control problem for a nonlinear multi-agent robot system with control input constraint and external disturbances. Robot system is one of the most important practical systems in the industry. Due to the presence of disturbances in most practical systems, this paper considers the issue of finite-time leader–follower consensus control of the nonlinear multi-agent robot system along with actuator saturation and bounded disturbance. The modified terminal sliding mode control method is suggested for the system which is able to guarantee the stability of the overall system and fast finite-time leader–follower consensus control. For two different scenarios, the simulation of multi-agent robot system has been performed. The results show the effectiveness of the proposed control method.

This paper addresses the consensus control problem for a nonlinear multi-agent robot system in the presence of external disturbances. Robot system is one of the most important practical systems in the industry. Because of the presence of disturbances in most practical systems, this paper considers the issue of finite-time consensus control of the nonlinear multi-agent robot system in the presence of unknown bounded disturbance. The modified terminal sliding mode control method is suggested for the system which is able to guarantee the stability of the overall system and fast finite-time consensus control purpose. In two different scenarios, the simulation of multi-agent robot system has been performed. The results show the effectiveness of the proposed control method on the multi-agent robot system.