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Polarization at interfaces is an important loss mechanism for electromagnetic wave (EMW) attenuation, though the motion behavior of carriers in interfaces composed of different types of conductors has yet to be investigated. Tuning the phase structure of transition metal dichalcogenides (TMDs) MS2 (M = Mo, V, W) by organics small molecule intercalation to achieve the modulation of interfacial types is an effective strategy, where 1T‐MS2 exhibits metallic properties and 2H‐MS2 has semiconducting properties. To exclude the contribution of the intrinsic properties of TMDs materials, three TMDs (MoS2, VS2, and WS2), which also possess phase transitions, are investigated. Among them, the 1T‐MS2 composite exhibits excellent EMW absorption performance under the synergistic effect of interfacial polarization and conduction loss. 1T‐MoS2/MOF‐A exhibits the best EMW absorption performance with an RLmin of −61.07 dB at a thickness of 3.0 mm and an EAB of 7.2 GHz at 2.3 mm. The effectiveness of the modulation of the interfacial polarization using 1T‐phase and 2H‐phase MS2 is demonstrated, which is important for the analysis of the carrier motion behavior during the interfacial loss. [ABSTRACT FROM AUTHOR]

A contact-force control and vibration suppression problem for a constrained one-link flexible manipulator with unknown control direction and time-varying actuator fault is discussed in this paper. The manipulator is described by a Partial Differential Equation model. The Nussbaum function is used to solve the unknown control direction and time-varying actuator fault problems. A Nussbaum function provides an adaptive boundary controller constructed to control the contact force to a target and simultaneously eliminate the vibration of the flexible manipulator. The Variable Separation Technique is used along with system boundary conditions to prove the necessary existence and uniqueness of the system solution more concisely than using the common C 0 -semigroup contractions method. Because force sensors are not necessary, the noise caused by a force sensor can be avoided. Numerical simulations verify the effectiveness of the proposed controller-based solution. [ABSTRACT FROM AUTHOR]

The eccentric harmonic magnetic gear (EHMG) has the characteristics of high torque density, high transmission ratio and high efficiency. The EHMG with Halbach array has better performance than the EHMG with traditional radial magnetization. Accurate calculation of its air‐gap magnetic field is of great significance for design and optimization. Based on the boundary perturbation method, a 2D analytical model of the air‐gap magnetic field of EHMG with Halbach array is established in this paper. The eccentric air‐gap magnetic field is calculated due to the permanent magnets of the eccentric rotor and the stator acting alone, and then the air‐gap magnetic field of the EHMG is obtained according to the superposition principle. The results of the air‐gap magnetic field are compared and evaluated by the regression evaluation indexes. The analytical results are consistent with the finite element results, which verifies the validity and accuracy of the analytical model. Comparing the EHMG with Halbach array and radial magnetization, the maximum static and dynamic electromagnetic torques of EHMG with Halbach array are increased by 59.1% and 55.6% compared with the EHMG with radial magnetization, which verifies the superior performance of EHMG with Halbach array. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

In network control, signal transmission between each system component is carried out through the communication network. Since the bandwidth of the network is limited, quantization is a vital and fundamental technology used to convert the continuous signal to an approximate signal with a finite number of discrete value levels. Furthermore, event-triggering is an effective method to reduce signal transmission frequency in network control. Input signal quantization and event-triggering are considered simultaneously in this study for a class of underactuated systems. First, the logarithmic quantizer is used to quantize the input signal, and then the quantized input signal is further processed by the event-triggered mechanism based on the fixed threshold strategy. Adopting the proposed adaptive control scheme with the aid of radial basis function (RBF) neural network-based sliding mode control, the states of the closed-loop system are guaranteed to be bounded, and the control goals can be achieved. Finally, the control effect is shown through the numerical simulations. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs), as emerging long afterglow luminescent material, have attracted the attention of researchers and become one of the hot topics in long afterglow materials. In recent years, researchers have obtained a series of CDs‐based long afterglow materials with different properties utilizing matrix‐assisted and self‐protective methods. To meet diverse application needs, the development of multicolor CDs‐based long afterglow materials is a focus and challenge in this field. Most of the previously reported CDs‐based long afterglow materials generally emit blue or green afterglow. Recently, some multicolor systems have been discovered, and the emission range can extend from ultraviolet to near‐infrared. However, there is a lack of systematic and in‐depth analysis regarding the preparation strategy and luminescence mechanism of multicolor afterglow from CDs‐based long afterglow materials. Based on this, this review summarizes the preparation strategies of multicolor afterglow from raw materials and reaction parameters. Then, the luminescence mechanisms of multicolor afterglow are analyzed from seven factors, including carbonization degree, surface state, aggregation degree, temperature dependence, excitation dependence, multi‐emission center, and energy transfer. Moreover, the applications of multicolor afterglow from CDs‐based long afterglow materials are introduced. Finally, the problems and challenges in this field are discussed, and the future development directions are analyzed. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this study reports the first direct electropolymerization of a dicyanobenzene-carbazole dye functionalized with an imidazole group to prepare redox- and photoactive porous organic polymer (POP) films in controlled amounts. The POP films were grown on indium-doped tin oxide (ITO) and carbon surfaces using a new monomer, 1-imidazole-2,4,6-tri(carbazol-9-yl)-3,5-dicyanobenzene (1, 3CzImIPN), through a simple one-step process. The structure and activities of the POP films were investigated as photoelectrodes for electrooxidations, as heterogeneous photocatalysts for photosynthetic olefin isomerizations, and for solid-state photoluminescence behavior tunable by lithium-ion concentrations in solution. The results demonstrate that the photoredox-POPs can be used as efficient photocatalysts, and they have potential applications in sensing. [ABSTRACT FROM AUTHOR]

This study proposes a novel boundary control strategy for a vibrating single‐link flexible manipulator system modeled by partial differential equations. The system has uncertain control directions and actuator faults. Existing research studies model fault‐tolerant control systems with fixed fault coefficients; in this study, the actuator faults are nonlinear and time‐varying, and the control directions are unknown. To circumvent the obstacles introduced by the unknown control directions and nonlinear varying actuator failures, an adaptive boundary controller is designed by using Nussbaum functions with fast growth rates and the bound estimation method. In the developed control scheme, all closed‐loop signals are shown to be uniformly bounded. Additionally, the angle tracking error and vibration asymptotically converge to zero. Finally, numerical simulations for five cases demonstrate the effectiveness of the modeled boundary controller. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the influence of pilocarpine eyedrops on the ocular biometric parameters and whether these parameter changes affect the intraocular lens (IOL) power calculation in patients with primary angle-closure glaucoma (PACG). Methods. Twenty-two PACG patients and fifteen normal subjects were enrolled. Ocular biometric parameters including the axial length (AL), anterior chamber depth (ACD), lens thickness (LT), mean keratometry (Km), and white-to-white distance (WTW) were measured by using a Lenstar LS 900 device before and at least 30 minutes after instillation of 2% pilocarpine eyedrops. Lens position (LP) was calculated, and the IOL power prediction based on the ocular biometric parameters was performed using the Barrett Universal II, Haigis, Hoffer Q, Holladay I, or SRK/T formulas before and after pilocarpine application. Results. In both PACG and normal groups, pilocarpine eyedrops induced a slight but statistically significant increase in the mean AL (0.01 mm for both groups) and mean LT (0.02 mm and 0.03 mm, respectively) but a significant decrease in the mean ACD (0.03 mm and 0.05 mm, respectively) and mean LP (0.02 mm and 0.04 mm, respectively). No significant changes in the mean Km and WTW were noticed in both groups. In addition, the IOL power calculation revealed insignificant changes before and after the pilocarpine instillation in both groups, regardless of the formula used. Conclusions. Pilocarpine eyedrops can induce slight changes in the ocular biometric parameters including the AL, ACD, LT, and LP. However, these parameter changes will not result in a significant difference in IOL power estimation. [ABSTRACT FROM AUTHOR]

In this article, modeling and vibration control issues are addressed for a nonlinear three‐dimensional flexible moving string system with input quantization and event‐triggering. The flexible string with a payload takes the bridge crane as a moving carrier. The system models are established by Hamilton's principle, including a group of partial differential equations and ordinary differential equations. Logarithmic and hysteretic quantizers are both adopted to compare quantitative effects, and then the quantized control input signals are processed effectively to further relieve communication burdens by event‐triggering, which is based on the fixed threshold strategy. The proposed control scheme can drive the cart to the desired position and suppress the vibration of the three‐dimensional flexible string. The uniform ultimate boundedness of the closed‐loop system is proved via the Lyapunov direct method. Finally, numerical simulations are carried out to verify the control effect. [ABSTRACT FROM AUTHOR]

In this study, we consider the event-triggered boundary control problem of a single-link flexible manipulator with uncertain end load. The flexible manipulator is modelled by partial differential equations (PDEs). Based on the PDE model, an event-triggered control strategy is proposed to achieve angular position tracking and vibration elimination, while alleviating the communication burden of the signal transmission between controller and actuator. The relative threshold strategy used in triggering event mechanism can adjust the update interval according to the size of the control input. The designed adaptive law with projection mapping operator can deal with undertain end load. The proposed control scheme can guarantee that all signals in the closed-loop system are uniformly ultimately bounded, and the angular tracking error and vibration converge to small zero neighbourhoods by reasonable selection of design parameters. Moreover, the Zeno phenomenon is precluded. Numerical simulation results elucidate the effectiveness of the designed control strategy. [ABSTRACT FROM AUTHOR]

This article aims at proposing an adaptive neural control strategy for a class of nonlinear time-delay systems with input delays and unknown control directions. Different from previous researches that investigated delays and constraints separately, the novelty of this article lies in that it simultaneously considers delays (state and input delays) and input constraints (magnitude and rate constraints) for a class of uncertain nonlinear systems. In this article, the uncertain states and input delays are handled by integrating a constructed auxiliary system that functions as an observer with neural networks (NNs), with which the adverse effects caused by the uncertain states and input delays can be approximated and compensated. By involving smooth hyperbolic tangent functions in the designed auxiliary system, the problem of magnitude and rate constraints of the control input is fully addressed. Then, the backstepping technique runs through the entire control designing process, which allows the designed adaptive neural control strategy to handle the input constraints and delays at the same time. Furthermore, Nussbaum functions are employed to resolve the problem of unknown control directions. Due to the introduction of an input-driven filter, only the output of the system is required to be measured as the control feedback, which promotes the applicability of the designed controller. Under the proposed control scheme, semiglobal, uniform, and ultimate boundedness of all signals of the closed-loop system is realized with uncertain control directions, input and state delays, and guaranteed magnitude and rate constraints of control inputs. Finally, simulation results are illustrated to verify the effectiveness of the presented control method. [ABSTRACT FROM AUTHOR]

Summary: This study investigates the event‐triggered adaptive control issues of a flexible manipulator when the control system is implemented over a network. The flexible manipulator has two actuators, which receive signals from the controller through the communication network. Given the limited communication problem of network and potential actuator failures, an event‐triggered adaptive fault‐tolerant controller is proposed based on the partial differential equation model. In our design, two event‐triggering mechanisms are introduced to avoid continuous signal transmission from the controller to the actuator. Then, an adaptive law using the projection mapping operator is designed to compensate for the impact of actuator failures. By employing the proposed control scheme, angular position tracking and vibration elimination can be achieved while reducing signal transmission, regardless of actuator failure. All closed‐loop signals are proved to be uniformly ultimately bounded. The control performance is demonstrated by numerical simulations. [ABSTRACT FROM AUTHOR]

• The emission wavelength of the CsCu 2 Br 3 single crystal is at 580 nm only. • CsCu 2 Br 3 single crystals treated by Isopropanol leads to precipitation of CuBr. • The 460 nm emission origins from CuBr rather than CsCu 2 Br 3. Lead-free low-dimensional perovskites have attracted much attention due to their advantages of high Photoluminescence quantum yield (PLQY) and visible light emission. In this paper, a new one-dimensional CsCu 2 Br 3 single crystal has been prepared successfully, and the differences in the optical properties influenced by surface cleaning treatments were investigated. The CsCu 2 Br 3 single crystal without surface damage can be obtained by the N 2 purging process without any solution rinsing. The photoluminescence peak of the pure CsCu 2 Br 3 phase is located at 580 nm, arising from the self-trapped exciton with the binding energy of about 173 meV. After the treatment of the isopropanol rinsing, the CuBr phase was formed on the surface of the as-grown CsCu 2 Br 3 single crystal. The stronger photoluminescence intensity can be directly observed by the naked eye, which was dominated by the CuBr phase with the emission peak at 460 nm. The above results show the importance of surface treatment and can explain the misunderstanding of the PL mechanism attributed to the dual self-trapped excitons. [ABSTRACT FROM AUTHOR]

In this paper, a robust adaptive fault‐tolerant control (FTC) strategy based on hyperbolic tangent function is proposed for a class of mechanical systems with unknown disturbance and unknown nonlinear friction model. The robust adaptive FTC algorithm proposed in this paper can maintain the system performance even after partial failure occurs in the actuator. Different from the traditional fault‐tolerant control algorithms, the proposed algorithm uses the hyperbolic tangent function and a projection algorithm to limit the control input within a known upper bound. In addition, radial basis function neural network is used to approximate the unknown continuous nonlinear function that contains the friction model in the mechanical system. The control target of the system is realized; and the asymptotic stability of the closed‐loop system is proved via the Lyapunov direct method. Finally, the numerical simulation results also demonstrate the effectiveness of the designed controller. [ABSTRACT FROM AUTHOR]

The vibration control problem was investigated in this study in the presence of unknown loss of actuator effectiveness fault and loss of sensor effectiveness fault in a flexible aircraft wing system. A series of partial differential equations was used as the mathematical model of the wing with unknown boundary disturbances. An adaptive fault-tolerant boundary controller was designed accordingly. All signals of the closed-loop control system are globally uniformly bounded and the controlled state asymptotically converges. Numerical simulations were conducted to validate the proposed control scheme. [ABSTRACT FROM AUTHOR]

In this paper, the modeling and control problem of an overhead crane equipped with a three-dimensional (3-D) variable length flexible cable is discussed. In order to achieve high control performance, a partial differential equation (PDE) model is deduced with exactly preserving high frequency modes of the original system. For the sake of dealing with the effect of input amplitude and rate constraints, a boundary control scheme is carried out to drive the payload to a desired position with the 3-D vibration reduction of the variable length cable by applying the backstepping technology. The exponential stability of the closed-loop system is demonstrated based on the Lyapunov’s direct method. The simulation results verify the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

This paper investigates a neural network control issue of a class of uncertain nonlinear systems. An adaptive quantized control strategy is developed such that the input quantization can be achieved using three different kinds of quantizers, and uncertain dynamics of system can be approximated and compensated by neural networks (NNs). Besides, a triggering event is addressed on the basis of a fixed and relative combined threshold strategy for relieving the communication load between the controller and actuator. With such control scheme, all signals of the closed-loop system are bounded and Lyapunov method is applied to prove the uniform ultimate boundedness of the control system. Simulation example is provided for illustrating tracking performance of the proposed control strategy. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic modelling and adaptive boundary control of a three-dimensional Timoshenko beam are presented for vibration suppression. In order to ensure that no modal information is left out, partial differential equations (PDEs) are employed to describe the nonlinear dynamic characteristics of the system by applying the extended Hamilton's principle. Based on the established model, barrier Lyapunov functions (BLFs) are utilised for dealing with system output restrictions. For practical consideration, parameter uncertainties and external disturbances are also taken into account. Under the proposed neural adaptive control scheme, undesirable elastic vibration of the three-dimensional Timoshenko beam is restricted and constrained within given bounds even subject to external perturbations, without needing to know any system parameters. The system stability is proved by the Lyapunov's direct method. The control performance is verified via using numerical simulations. [ABSTRACT FROM AUTHOR]

In this paper, we consider boundary control for a single-link flexible manipulator system described by partial differential equations (PDEs). Existing researches on controller design rarely consider the problem of communication capacity constrains during signal transmission. To deal with this problem, an adaptive control is designed to achieve the input quantization by using the random quantizer. Besides, a triggering event is addressed on the basis of relative threshold strategy for relieving communication load between controller and actuator. The proposed scheme is able to ensure that all closed-loop signals are globally uniformly bounded, and the angular tracking error and vibration converge to a residual set. Simulation results are presented to illustrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

In this article, we introduced a novel definition for a class of extended Nussbaum functions that have looser requirements than the traditional Nussbaum function. The extended Nussbaum function achieves comparable performance to the traditional Nussbaum function while addressing the challenges of unknown control directions and time‐varying actuator faults. We then provide a specific example function based on the extended Nussbaum function definition. Unlike the traditional Nussbaum function, which oscillates with fixed frequency and constantly increasing amplitude, this example function constrains the amplitude and oscillates with decreasing frequency. Consequently, its amplitude and derivative remain bounded. The oscillation of the system caused by the too large amplitude of the traditional Nussbaum function can be avoided. Furthermore, this example function is constructed using portions of elliptic curve. As a result, it is continuous and differentiable, in contrast to the normal decreasing‐frequency Nussbaum function using trigonometric function, which is only continuous. The overall closed‐loop system's global stability and asymptotic convergence of system states are successfully achieved. Simulation results demonstrate the effectiveness of the proposed function. [ABSTRACT FROM AUTHOR]

In this article, boundary control strategy is adopted to suppress the vibration of a flexible three‐dimensional (3D) marine riser simultaneously against both sensor and actuator faults. The flexible 3D marine riser is a distributed parameter system modeled as partial differential equations. During normal operation of the system, all the system components will behave optimally. However, if the sensor and actuator appear fault, the system will work abnormally. While the sensor is faulty, the output signal of the sensor will have errors, and this error signal will be the input signal of the actuator. In terms of actuator fault, once the actuator appears fault problem, the actuator should make up for the fault and continue working for the sake of safety. In this work, the fault degree of sensors and actuators are unknown and the boundary control schemes using Nassbaum function are developed for fault compensation. The system stability is proven by introducing an appropriate Lyapunov function. Finally, the simulation results verify the accuracy of the proposed control laws. [ABSTRACT FROM AUTHOR]

[Display omitted] • Changing the sputtering order created monolayer, double layer, and co-existence structures. • Coatings enhanced the hydrophilicity and corrosion resistance of Ti substrate. • Multi-mechanisms made the antibacterial rate reach 99.99% within 0.5 h contact. • Composite coatings promoted the proliferation and adhesion of MC3T3-E1 cells. To obtain an overall enhancement on corrosion resistance, antimicrobial efficacies, and cytocompatibility of titanium-based implants, the multifunctional coatings in the forms of mono, double, and co-existence based on CuO and ZnO were innovatively designed by regulating the sputtering orders under magnetron sputtering. The results showed that ZnO and CuO were pure phases, CuO grains performed large and unevenly while ZnO grains were fine and homogeneous, such grains morphology features remerged on double-layered coatings. The surface roughness (R q) of the monolayer to the double layer and then to the co-existing one was increased from 2.58 nm to 18 nm to 22.6 nm. All multifunctional coatings helped to lower the contact angle to a minimum of 18.82°, and enhanced the corrosion potential to a maximum of −0.261 V. The released ions, grains piercing, and ROS produced by p-n junctions co-played the bactericidal roles, which equipped ZnO/CuO composite coatings with bactericidal rates of 90.24%∼100% as directly contact with the target germs in 0.5 h. Owing to the strong metal–oxygen bonding and rough surface, all coatings supported the cell viabilities of 137.92%∼145.27% through 120 h co-culturing, MC3T3-E1 cells healthily proliferated and adhered on the surface. The double-layered coating, with ZnO as the bottom layer and CuO as the upper layer, exhibited better overall properties. [ABSTRACT FROM AUTHOR]

• A series of CDs@Al 2 O 3 were prepared by regulating the reaction temperature. • CDs@Al 2 O 3 exhibits ultra-broad afterglow emission range from 376 to 619 nm. • Afterglow emission mode of the CDs@Al 2 O 3 shifted from RTP to TADF. • Multiple anti-counterfeiting, information encryption, and fingerprint detection are demonstrated by CDs@Al 2 O 3. • Energy transfer process from CDs to the matrix was observed. The room temperature afterglow (RTA) of carbon dots (CDs) and their wide-ranging application prospects have attracted significant attention. However, most of the synthesis and regulation methods for multicolor CDs-based RTA materials are complex. Therefore, it is still a challenge to obtain a series of CDs-based RTA materials with broad and tunable emission wavelengths via a simple preparation method using the same organic precursor and matrix. In this study, a series of CDs@Al 2 O 3 materials with ultra-broad afterglow emission range (376 ∼ 619 nm) were prepared by regulating the reaction temperature through a one-step calcination method. High-temperature consumption led to a decrease of surface functional groups and conjugation size of CDs, resulting in the gradually blue-shifted emission from red to UV region. We also discovered a unique phenomenon where the afterglow emission mode of the material shifted from room temperature phosphorescence (RTP) to thermally activated delayed fluorescence (TADF) as the temperature increased, attributed to the stabilization of the excited triplet state from the strengthened crystallinity of Al 2 O 3 matrix. Furthermore, a continuous emission at ∼ 471 nm attributed to the oxygen defects of the matrix was observed. Multiple anti-counterfeiting, information encryption, and fingerprint detection are demonstrated based on the unique RTA properties of CDs@Al 2 O 3. [ABSTRACT FROM AUTHOR]

A sliding mode control method is developed in this study for application to a class of underactuated systems with bounded unknown disturbance and sensor and actuator faults. In the proposed method, a robustness item compensates for the bounded unknown disturbance and a Nussbaum function realises sensor and actuator faults tolerance simultaneously, and all signals of the system are proven to be bounded. A radial basis function (RBF) neural network is developed to estimate the unknown functions of the system. Finally, Hurwitz stability analysis is conducted to guarantee the stability of the closed-loop system. Simulations are conducted wherein a coupled motor driving system is placed under the proposed control laws to validate this approach. [ABSTRACT FROM AUTHOR]

The infructescence of Platycarya strobilacea Sieb. et Zucc. (PS) has been used in the treatment of rhinitis and sinusitis in clinical practice. Our preliminary study showed that an ethanol extract of the infructescence of PS (EPS) had significant antinasopharyngeal carcinoma (NPC) effects in vitro. However, the mechanism underlying the NPS cell death induced by EPS remains unclear. The aim of the present study was to investigate the inhibitory effects of EPS on NPC cells and to elucidate the underlying mechanism. The effects of EPS on NPC cells were investigated in CNE1 and CNE2 cells in vitro. In EPS-treated cells, the cell morphological changes were evaluated through fluorescence microscope, transmission electron microscopy, and flow cytometry. The underlying mechanism was analyzed via network pharmacology and further verified by western blot analysis. The anticancer effects of EPS were associated with the generation of CNE1 and CNE2 cell fusion and vacuoles, the perturbation of lysosomal vesicle transportation, and the induction of methuosis. The network pharmacology and western blot results indicated that the effect of EPS in NPC cells might be achieved via regulation of the Ras proto-oncogene (RAS)/mitogen-activated protein kinase (MAPK) signaling pathway and the transcription factor c-Fos proto-oncogene (c-FOS) and its downstream genes. EPS induces NPC cell death through methuosis. The mechanism might be related to regulation of the transcription factor c-FOS and its downstream genes. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive fault-tolerant boundary vibration control method designed to resolve unknown failure and stuck actuator problems in the wind turbine blade control process. The blade is modelled as a distributed parameter system described by two coupled partial differential equations. The proposed boundary control achieved the fact that the vibration of the blade can still be suppressed even when the actuator fails, and the bending and torsional deformation is eventually reduced to zero. Based on the Lyapunov direct method, a fact has been confirmed that the stability of the system is guaranteed under the boundary controller. The effectiveness of the controllers is demonstrated by numerical simulations. [ABSTRACT FROM AUTHOR]

In this paper, we study the vibration control for a flexible satellite with adaptive actuator fault-tolerant and input quantization. The control objective is to suppress the vibration of a flexible satellite as well as considering actuator fault-tolerant and input signal quantization. The flexible satellite is composed of a centrebody and two symmetrical flexible solar panels. The symmetrical flexible solar panels are described as two Euler-Bernoulli beams modeled as partial differential equations (PDEs). Quantitative control combines control and communication to solve related control problems in modern engineering systems. Logarithmic quantitative controllers are used to realize input signal quantization. Meanwhile, an adaptive control scheme is designed to regulate the vibration of the satellite when the actuator fails partially. Simulation results are demonstrated for illustration. It is proved that the proposed control scheme can handle the vibration of the flexible satellite as well as considering actuator fault-tolerant and input signal quantization simultaneously. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive fault-tolerant control scheme for a single-link flexible manipulator with actuator failure and uncertain boundary disturbance. The dynamic model of the flexible manipulator as-described by partial differential equations (PDEs) is derived under Hamilton's principle. The dynamic model is then used to design an adaptive fault-tolerant control (FTC) scheme which tracks the given angle and regulates vibration in the case of actuator failure. The boundary disturbance is compensated by a radial basis function (RBF) neural network. The whole closed-loop system is proven asymptotically stable by Lyapunov direct method and LaSalle's invariance principle. Simulation results indicate that the proposed controller is superior to the traditional PD controller. [ABSTRACT FROM AUTHOR]

In this study, problems of the partial differential equation (PDE) modelling and vibration control design are first resolved for an overhead crane bridge system, which is regarded as a Timoshenko beam with an attached rigid body. With the established infinite‐dimensional PDE model, a Nussbaum function‐based adaptive control approach is developed in order to settle out parametric uncertainties of the system with unknown control directions. Under the proposed control method, states of the overhead crane bridge are globally bounded and finally converge to an adjustable region of zero. The stability of the closed‐loop overhead crane bridge system is analysed by employing Lyapunov's direct method. The effectiveness of the developed control strategy is verified through the simulation results. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the control problem for a two-link rigid–flexible manipulator with input quantization. Abundant studies of the quantized control problem are based on the lumped parameter system, which is expressed using ordinary differential equations. In this paper, the dynamic model for a two-link rigid–flexible manipulator is represented using partial differential equations. The controller design and analysis with input quantization are based on the partial differential equation model. By means of an auxiliary system, tracking errors and boundary vibrations can be eliminated. Simulations are given to verify the effectiveness of the proposed controller with quantized input. [ABSTRACT FROM AUTHOR]

Summary: In this paper, an adaptive neural network control system is developed for a nonlinear three‐dimensional Euler‐Bernoulli beam with unknown control direction. The Euler‐Bernoulli beam is modeled as a combination of partial differential equations (PDEs) and ordinary differential equations (ODEs). Adaptive radial basis function–based neural network control laws are designed to determine approximation of disturbances. A projection mapping operator is adopted to realize bounded approximation of disturbances. A Nussbaum function is introduced to compensate for the unknown control direction. The goal of this study is to suppress the vibrations of the Euler‐Bernoulli beam in three‐dimensional space. In addition, unknown control direction problem and bounded disturbances are considered to guarantee that the signals of the system are uniformly bounded. Numerical simulations demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This meta-analysis aims to evaluate the effectiveness of chemotherapy before (I-CRT) or after (CRT-C) chemoradiotherapy (CRT) for inoperable locally advanced non-small cell lung cancer (LA-NSCLC). According to the object response rate (ORR) and disease control rate (DCR), there were no differences among I-CRT, CRT, and CRT-C treatments. I-CRT did not have significant survival benefits compared with CRT alone. Similar results comparing CRT-C with CRT were observed. Furthermore, I-CRT was not associated with improved survival compared to CRT-C with respect to OS and PFS. Our meta-analysis suggests the effects of additional chemotherapy added to CRT were limited for unselected LA-NSCLC. [ABSTRACT FROM AUTHOR]

In this paper, boundary and distributed controllers are proposed to reduce the vibration of a flexible string with external disturbance. To accurately represent the flexible string's behaviour, partial differential equations are introduced for the flexible string modelling. Boundary and distributed disturbance observers, which are proved exponentially stable, are designed to compensate unknown disturbance. Based on the proposed disturbance observers, the boundary and distributed controllers are developed by linear matrix inequality and the asymptotic stability of the system with controllers is demonstrated by Lyapunov's direct method. Extensive numerical simulations are presented to validate the good performance of the proposed control laws. [ABSTRACT FROM AUTHOR]

Summary: In this paper, modeling and controlling problem for a two‐link rigid‐flexible manipulator in three‐dimensional (3D) space is studied under actuator faults. For modeling, the dynamics of the 3D mechanical system is represented by nonlinear partial differential equations, which is first derived in infinite dimension form. Based on the nonlinear model, the controller is proposed, which can achieve joint angle control and vibration suppression control in the presence of actuator faults. The stability analysis of the closed‐loop system is given based on LaSalle invariance principle. Numerical simulations illustrate the effectiveness of the proposed controller. This study will promote the development of nonlinear flexible manipulator systems in 3D space. [ABSTRACT FROM AUTHOR]

Summary: The consensus tracking mechanism of a multi‐agent system consisting of third‐order nonlinear single joint manipulators was investigated in this study based on the pertinent industrial context. Unlike many previous studies on consensus control that presumed a known control direction, this investigation addressed the complex challenges posed by unknown control directions and time‐varying actuators. Specifically, we explored both time‐invariant and time‐varying actuator faults in scenarios wherein all parameters are unknown. The Nussbaum function was utilized to resolve time‐varying nonlinear fault‐tolerance and unknown control direction problems. In the design process of the control law, the backstepping method combining with Nussbaum function is adopted to address unmatched nonlinearity and unmatched uncertainty system, and the radial basis function neural network is used to approximate the unknown parameters The resulting control law allows all robotic manipulators to track the angle and angular velocity of the leader. Simulation results demonstrate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Summary: In this brief, this paper deals with a robust adaptive iterative learning control (ILC) problem for a flexible manipulator attached to a moving vehicle with uncertainties. To begin with, considering the infinite dimensionality of the flexible distributed parameter system, a coupled ordinary differential equation and partial differential equation model is established without any discretization. Then, it is followed by a presentation of an adaptive ILC strategy, which can drive the vehicle and joint to the desired positions based on a proportional‐derivative feedback structure with unmodeled dynamics and external disturbances. The deformation of the flexible manipulator can also be suppressed simultaneously under the proposed control laws. By using Lyapunov's direct method, the stability of the closed‐loop system is demonstrated. The simulation results are provided to illustrate the effectiveness of the proposed control laws. [ABSTRACT FROM AUTHOR]

Abstract In this study, we investigate the state-feedback control problem of a moving vehicle-mounted flexible manipulator with output constraints. Both position regulation and vibration suppression can be accurately carried out based on the partial differential equation (PDE) model we established. The dynamics of piezoelectric actuators and sensors are considered for compensating the gravity effect of the flexible manipulator in the modeling and prescribed performance can be guaranteed with the aid of the performance functions. Further, the tracking error can converge to an arbitrarily small residual set with convergence rate no less than a pre-specified value. State variables of the closed-loop system are proved to be asymptotically stable by using Lyapunov's direct method and the extended LaSalle's Invariance Principle. Simulations are included to validate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the dynamic modeling and vibration control of a two-blade propeller system of an aircraft are investigated in the presence of input magnitude and rate constraints and external disturbances. To avoid discretizing the original system, a partial differential equation (PDE) model preserving all system modes is developed. Based on the proposed PDE model, boundary control laws are derived to restrict the bending and twist deformations of the two-blade propeller under disturbances. To meet the input magnitude and rate constraints, a backstepping controller is designed. The closed-loop system stability is proved by using the Lyapunov's direct method. Numerical simulations are presented to demonstrate the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive boundary controller for an undersea detection robot system with actuator failure, unknown disturbance and boundary deflection constraint is proposed. Using Hamilton's principle, a partial differential equation (PDE) model is established for the detection system, which consists of a rigid arm, a flexible string and a sensor. Considering the actuator failure, a fault-tolerant scheme is proposed to tackle it. To handle the unknown disturbance, we employ radial basis function (RBF) neural networks (NNs) to neutralize the boundary uncertain nonlinear disturbance. The proposed adaptive controller includes a proportional–derivative (PD) feedback structure, a fault-tolerant strategy and a NN control scheme. By choosing an appropriate Lyapunov-Krasovskii function and applying LaSalle's Invariance Principle, the asymptotic stability of the closed-loop system is rigorously proven. Simulation results validate the proposed controller. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we present fault tolerant control design for a class of cascaded systems described by ordinary differential equations (ODEs) and an Euler–Bernoulli beam (EBB). The objective of this study is to design a robust adaptive fault tolerant control such that the global stability of the resulting closed-loop cascaded system is ensured and asymptotic tracking can be achieved subject to actuator failures, parameter uncertainty and external disturbances. The Lyapunov's direct method is used to design the control schemes and prove the stability of the closed-loop system. Finally, the results are illustrated using numerical simulations for control performance verification. [ABSTRACT FROM AUTHOR]

This study focuses on the disturbance observer design and vibration control problems for a flexible aircraft wing system. The flexible aircraft wing is modeled as a coupled twist-bending infinite dimensional distributed parameter system. The dynamic equations and boundary conditions are described by partial differential equations and ordinary differential equations, respectively. In this paper, an infinite dimensional disturbance observer is proposed to estimate both the boundary disturbances and the distributed spatiotemporally varying disturbances. Considering the coupling between the bending deformation and the twist deformation, a boundary controller is proposed to suppress the vibration and inhibit the adverse effects of external disturbances. By using the proposed disturbance observer and controller, the uniform boundednesss of the closed-loop system is validated through theoretical analysis. Finally, simulation results are carried out to illustrate the effectiveness of the proposed infinite dimensional disturbance observer and boundary controller. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes an adaptive boundary control scheme for the flexible three‐dimensional Euler‐Bernoulli beam with input signal quantization. Considering the coupling effect between the axial deformation and the transverse displacement, the dynamics of the flexible system are represented by partial differential equations and ordinary differential equations. Input signals in modern control systems are often quantized before being transmitted through communication channels in technology engineering. Logarithmic quantitative controllers are designed to suppress the vibration of the beam. It is proved that the proposed control scheme can be guaranteed in handling the vibration of the beam and input signal quantization simultaneously. Finally, numerical simulations illustrate the effectiveness of the results. [ABSTRACT FROM AUTHOR]

Highlights: The hierarchical porous structure is regulated by various species of PVP to achieve impedance matching. Interfacial engineering boosts conductivity and constructs a multiband (C, X, Ku) tunable electromagnetic wave absorber. Hierarchical porous molybdenum selenide/epoxy coating exhibits marine anticorrosion capability. Electromagnetic wave (EMW) absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution control. And in order to cope with the complex electromagnetic environment, the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous challenge. In this work, we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the absorber. Also, through interfacial engineering, a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the absorber. The analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial engineering. Wherein, the prepared MoSe2/MoC/PNC composites showed excellent EMW absorption performance in C, X, and Ku bands, especially exhibiting a reflection loss of − 59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 mm. The coordination between structure and components endows the absorber with strong absorption, broad bandwidth, thin thickness, and multi-frequency absorption characteristics. Remarkably, it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel substrate. This study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers, and provides a reference for the design of multifunctional, multiband EMW absorption materials. [ABSTRACT FROM AUTHOR]

In this paper, the actuator fault problem is studied for a two-link rigid-flexible manipulator system in the presence of boundary disturbance and state constraint. The system consists of a rigid beam, a flexible beam and a payload at the end, which are described by hybrid ordinary differential equations-partial differential equations. The novel controller includes a proportional-derivative feedback structure, a disturbance observer and a fault-tolerant algorithm, which can regulate the joint positions and eliminate vibration of flexible beam, on circumstance of boundary disturbance and actuator fault. With the help of Barrier Lyapunov Function, the states will not be violated. It is proved that the closed-loop system has asymptotic stability by LaSalle Invariance Principle. Simulations are provided to demonstrate the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]