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The lanes merging control is discussed in this paper for the vehicle platoon while the distance as well as bearing angle constraints among the adjacent vehicles are considered. Differing from the existing strategies, some practical concerns are discussed and dealt with in the controller design. First, to lower the dependence on an accurate system model, an ultra‐local model‐based system description is given. Moreover, an adaptive sliding mode disturbance observer is hence constructed so as to offset the lumped disturbance in the newly transformed system. Second, we divide the multi‐lane fusion target into two parts, namely the distance keeping and bearing angle tracking. Specifically, the distance keeping rules are ensured by utilizing the interval expression‐based prescribed performance control and the newly designed time‐varying integral barrier Lyapunov function. As for the bearing angle tracking, the constraints on the bearing angle and the vehicle's angular velocity are guaranteed by the integral barrier Lyapunov function. In addition to these, the event‐triggered control scheme is also considered during the distance keeping and bearing angle tracking so as to reduce the communication burden. Finally, simulation results are provided to show the effectiveness of the given control strategy. [ABSTRACT FROM AUTHOR]

Pathogenic pathogens invade the human body through various pathways, causing damage to host cells, tissues, and their functions, ultimately leading to the development of diseases and posing a threat to human health. The rapid and accurate detection of pathogenic pathogens in humans is crucial and pressing. Nucleic acid detection offers advantages such as higher sensitivity, accuracy, and specificity compared to antibody and antigen detection methods. However, conventional nucleic acid testing is time-consuming, labor-intensive, and requires sophisticated equipment and specialized medical personnel. Therefore, this review focuses on advanced nucleic acid testing systems that aim to address the issues of testing time, portability, degree of automation, and cross-contamination. These systems include extraction-free rapid nucleic acid testing, fully automated extraction, amplification, and detection, as well as fully enclosed testing and commercial nucleic acid testing equipment. Additionally, the biochemical methods used for extraction, amplification, and detection in nucleic acid testing are briefly described. We hope that this review will inspire further research and the development of more suitable extraction-free reagents and fully automated testing devices for rapid, point-of-care diagnostics. [ABSTRACT FROM AUTHOR]

This article investigates the robust fault tolerant control strategy for a rigid satellite attitude system with external disturbance and actuator fault while the predesigned output constraint is taken into consideration. Based on the interval observer technique, an identical faulty signal reconstruction is first realized by utilizing pure mathematical calculation. Then, to guarantee the desired output constraint, the proposed prescribed performance fault tolerant control framework is constructed with a novel error interval representation which not only reduces the computation burden but also simplifies the output constrained controller design. In addition, by comparing with the existing finite/fixed time control method, the setting time for this control strategy can be assigned freely. The stability of the whole method is guaranteed by Lyapunov method. Finally, simulation results including comparisons with existing work show the effectiveness and advantages of the proposed approach. [ABSTRACT FROM AUTHOR]

This study proposes an integrated fault estimation (FE) and fault‐tolerant control design for a rigid spacecraft attitude system with inertia uncertainties, external disturbances, input saturation, and different type multiple actuator faults. A barrier function is first introduced to eliminate the effects of inertia uncertainties and disturbances in the design of the sliding mode FE observer. By using the non‐singular fast terminal sliding mode control technology, a finite‐time fault‐tolerant attitude stabilisation controller and a finite‐time fault‐tolerant attitude tracking controller are designed to guarantee that the closed‐loop attitude system has a good fault‐tolerant performance under actuator faults. Furthermore, when considering actuator saturation, an auxiliary system is utilised to compensate for the saturation. The stability of the closed‐loop system is analysed by Lyapunov theory. Finally, the effectiveness of the proposed control approach is demonstrated via simulation results. [ABSTRACT FROM AUTHOR]

This study investigates the active fault tolerant control (FTC) problem for the attitude system of a rigid satellite, which is affected by parameter uncertainty, unknown exogenous disturbance and actuator time‐varying faults. The upper bounds of the actuator time‐varying fault and the generalised perturbation are unknown. A novel adaptive non‐linear fault estimation observer is designed in order to obtain the estimated value of unknown time‐varying faults. Then, an active fault tolerant attitude control approach is proposed under the framework of both backstepping control and adaptive control theory. Consequently, the Lyapunov theory is used to prove the robust asymptotic stability for the closed‐loop attitude system of a faulty satellite under the proposed FTC scheme. Finally, simulation results on an in‐orbit rigid satellite are provided to show the good fault tolerant performance, which validate the effectiveness and feasibility of the proposed scheme. [ABSTRACT FROM AUTHOR]

With the emergence of fifth-generation (5G) cellular networks, millimeter-wave (mmW) and terahertz (THz) frequencies have attracted ever-growing interest for advanced wireless applications. The traditional printed circuit board materials have become uncompetitive at such high frequencies due to their high dielectric loss and large water absorption rates. As a promising high-frequency alternative, liquid crystal polymers (LCPs) have been widely investigated for use in circuit devices, chip integration, and module packaging over the last decade due to their low loss tangent up to 1.8 THz and good hermeticity. The previous review articles have summarized the chemical properties of LCP films, flexible LCP antennas, and LCP-based antenna-in-package and system-in-package technologies for 5G applications, although these articles did not discuss synthetic LCP technologies. In addition to wireless applications, the attractive mechanical, chemical, and thermal properties of LCP films enable interesting applications in micro-electro-mechanical systems (MEMS), biomedical electronics, and microfluidics, which have not been summarized to date. Here, a comprehensive review of flexible LCP technologies covering electric circuits, antennas, integration and packaging technologies, front-end modules, MEMS, biomedical devices, and microfluidics from microwave to THz frequencies is presented for the first time, which gives a broad introduction for those outside or just entering the field and provides perspective and breadth for those who are well established in the field. [ABSTRACT FROM AUTHOR]