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In this paper, the H∞$$ {H}_{\infty } $$ optimal output tracking control problem for Markov jump systems is investigated, where the two cases with known or completely unknown transition probabilities are both considered. Based on game theory and H∞$$ {H}_{\infty } $$ performance, quadratic cost is considered, where a discount parameter is introduced into the quadratic cost in order to track unstable systems and eliminate the assumption that the noise energy is bounded. The game coupled algebraic Riccati equation and the corresponding controller are presented by dynamic programming. The stochastic stability of the tracking error system is further investigated. Moreover, iterative and reinforcement learning‐based algorithms are proposed for solving the H∞$$ {H}_{\infty } $$ optimal tracking controller with known or completely unknown transition probabilities, respectively. Finally, some numerical simulations on a DC motor are performed to validate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

Recently, boron (B)/nitrogen (N)‐embedded polycyclic aromatic hydrocarbons (PAHs), characterized by multiple resonances (MR), have attracted significant attention owing to their remarkable features of efficient narrowband emissions with small full width at half maxima (FWHMs). However, developing ultra‐narrowband pure‐green emitters that comply with the Broadcast Service Television 2020 (BT2020) standard remains challenging. Precise regulation of the MR distribution regions allows simultaneously achieving the emission maximum, FWHM value, and spectral shape that satisfy the BT2020 standard. The proof‐of‐concept molecule TPABO‐DICz exhibited ultrapure green emission with a dominant peak at 515 nm, an extremely small FWHM of 17 nm, and Commission Internationale de l′Eclairage (CIE) coordinates of (0.17, 0.76). The corresponding bottom‐emitting organic light‐emitting diode (OLED) exhibited a remarkably high CIEy value (0.74) and maximum external quantum efficiency (25.8 %). Notably, the top‐emitting OLED achieved nearly BT2020 green color (CIE: 0.14, 0.79) and exhibited a state‐of‐the‐art maximum current efficiency of 226.4 cd A−1, thus fully confirming the effectiveness of the above strategy. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY) is regarded as an exceptional candidate to meet the growing demand in many fields due to its rich chemical bonds, highly π‐conjugated structure, uniformly distributed pores, large surface area, and high inhomogeneity of charge distribution. The extensive research efforts bring about a rapid expansion of GDY with a variety of functionalities, which significantly enhance performance including photocatalysis, energy, biomedicine, etc. In this review, the synthetic strategies (in situ and ex situ approaches) that are designed to rationally functionalize GDY, including optimizing their nanostructures by surface/interface engineering with dopants or functional groups (heteroatoms/small molecules/macromolecules), and building up hierarchical GDY‐based heterostructures are highlighted. Theoretical calculations on the structural evolution and electronic characteristics after the functionalization of GDY are briefly discussed. With elaborate functionalization and rational structure engineering, functional GDY applied in a variety of emerging applications (e.g., hydrogen evolution reaction, CO2 reduction reaction, nitrogen reduction reaction, energy storage and conversion, nanophotonics, sensors, biomedical applications, etc.) are comprehensively discussed. Finally, challenges and prospects concerning the future development of GDY‐based nanoarchitectures are also presented. [ABSTRACT FROM AUTHOR]

This article addresses the leader‐follower formation control problem for a group of quadrotors using only relative bearing measurements. Most existing methods require full position or velocity information, which cis challenging to obtain in harsh environments. In contrast, the proposed control scheme is based on a hierarchical system that does not rely on relative position or velocity measurements. The bearing‐only control law is designed to stabilize the desired formation, and each quadrotor maintains predetermined bearings with its neighbors. The control design relies on a non‐singular extraction algorithm for separate design of translation and rotation control. The outer loop of the control scheme utilizes a filter‐like approach to overcome the lack of bearing rate measurements in the bearing‐only formation controller. Moreover, employing differentiators following the separation principle with properties of asymptotic high accuracy, a uniform differentiator is provided for each following quadrotor to overcome the absence of linear velocity and acceleration feedback in the inner‐loop controller. Ultimately, the efficacy of the proposed control strategy is validated through a combination of Lyapunov stability theory and extensive numerical simulations. [ABSTRACT FROM AUTHOR]

This work focuses on the output tracking control for a class of continuous‐time semi‐Markov jump systems (SMJSs). In the controller design, not only the finite‐time stochastic boundedness (FTSB), but also the dissipative performance over a finite‐time interval is considered. In order to save communication resources, a version of adaptive event‐triggered mechanism (AETM) is utilized. Different from the traditional static event‐triggered mechanism, the threshold coefficient in AETM is time‐varying and can be adjusted in real‐time to fit the system evolution. Moreover, the asynchronous switching between the controller modes and the plant modes is taken into account. The design objective is to synthesis an adaptive event‐triggered asynchronous state‐feedback controller such that not only the augmented closed‐loop system is FTSB with a certain level of dissipative performance, but also the communication burden can be reduced to some extent. It is the first attempt to investigate the output tracking control of SMJSs over a finite‐time interval. By constructing a plant model‐dependent Lyapunov function, a set of conditions is derived for the FTSB analysis, based on which a controller design algorithm is presented. Finally, an illustrative example is given to verify the availability of the theoretical findings. [ABSTRACT FROM AUTHOR]

Control laws can be constructed in systems design by introducing parameters to obtain good system performance or robustness. Cai et al., in their paper 'Design of LPV controller for morphing aircraft using inexact scheduling parameters', establish a linear parameter-varying model for a morphing aircraft by Jacobian linearization. With such a model, Cai et al. investigate the design problem of gain-scheduled output-feedback controllers by using inexact scheduling parameters for morphing aircraft during the wing transition process. [Extracted from the article]

Circularly polarized organic light‐emitting diodes (CP‐OLEDs) are ideal candidates to explore novel applications such as 3D displays, optical storage, and quantum computing. However, the low dissymmetry (g) factor of most chiral organic materials remains as a major challenge for practical applications. In this work, a helical stacking assembly of orderly silicon nanowires (hs‐SiNWs) into a flexible multilayer 3D superstructure is demonstrated to accomplish a strong chiroptical activity. These orderly SiNWs are batch‐fabricated via a low temperature in‐plane solid–liquid–solid growth mechanism, with precisely‐controlled spatial arrangement and mean diameter and length of Dnw = 126 ± 24 nm and Lnw > 100 µm, respectively. To construct such helically‐stacked superstructure, the SiNW arrays are transferred and stacked upon transparent glass or flexible polymer substrates, with incremental rotational angle for each layer, which can strongly augment the circularly polarized electroluminescence (CPEL) from conventional CP‐OLEDs. Strikingly, the dissymmetry factor increases with more stacking layer up to g = ±0.17, which is more than 40 times of magnitude higher than that of the original CPEL, among the highest ones reported for CP‐OLEDs. These results indicate a promising helical‐stacking avenue to boost the chiroptical performance of various CP‐OLEDs for scalable and flexible chiroptical applications. [ABSTRACT FROM AUTHOR]

To concurrently realize large electroluminescence dissymmetry factor and high device efficiency remains a formidable challenge in the development of circularly polarized organic light‐emitting diode (CP‐OLED). In this work, by introducing a famous chiral resource of R‐camphor, two green chiral iridium(III) isomers of Λ/Δ‐Ir‐(R‐camphor) containing dual stereogenic centers at iridium and ancillary ligand, are efficiently synthesized. Benefiting from their high phosphorescence quantum yields (≈93%) and obvious circularly polarized photoluminescence property with dissymmetry factors (|gPL|) in the 10−3 order of magnitude, the circularly polarized phosphorescent organic light‐emitting diodes using these chiral emitters show excellent performances with the maximum external quantum efficiency (EQEmax) of 30.6%, low efficiency roll‐off, and intense circularly polarized electroluminescence signal with dissymmetry factor (gEL) in the 10−4 order of magnitude. By the novel device engineering with semitransparent cathode, the resulting gEL values are significantly boosted by one order of magnitude, up to 7.70 × 10−3, which is the highest among the CP‐OLEDs with chiral iridium complexes. Noteworthy, the semitransparent devices deliver a record‐high EQEmax of 18.8% among the semitransparent OLEDs. The combination of novel chiral Ir(III) complexes and the semitransparent devices sheds light on the development of high performance CP‐OLEDs with simultaneously high efficiency and large dissymmetry factor. [ABSTRACT FROM AUTHOR]

To concurrently realize large electroluminescence dissymmetry factor and high device efficiency remains a formidable challenge in the development of circularly polarized organic light‐emitting diode (CP‐OLED). In this work, by introducing a famous chiral resource of R‐camphor, two green chiral iridium(III) isomers of Λ/Δ‐Ir‐(R‐camphor) containing dual stereogenic centers at iridium and ancillary ligand, are efficiently synthesized. Benefiting from their high phosphorescence quantum yields (≈93%) and obvious circularly polarized photoluminescence property with dissymmetry factors (|gPL|) in the 10−3 order of magnitude, the circularly polarized phosphorescent organic light‐emitting diodes using these chiral emitters show excellent performances with the maximum external quantum efficiency (EQEmax) of 30.6%, low efficiency roll‐off, and intense circularly polarized electroluminescence signal with dissymmetry factor (gEL) in the 10−4 order of magnitude. By the novel device engineering with semitransparent cathode, the resulting gEL values are significantly boosted by one order of magnitude, up to 7.70 × 10−3, which is the highest among the CP‐OLEDs with chiral iridium complexes. Noteworthy, the semitransparent devices deliver a record‐high EQEmax of 18.8% among the semitransparent OLEDs. The combination of novel chiral Ir(III) complexes and the semitransparent devices sheds light on the development of high performance CP‐OLEDs with simultaneously high efficiency and large dissymmetry factor. [ABSTRACT FROM AUTHOR]

Circularly polarized organic light‐emitting diodes (CP‐OLEDs) that enable circularly polarized luminescence (CPL) are promising for 3D display and photonic applications. However, the device efficiency and CPL character of CP‐OLEDs still lag behind the practical requirements. Here, two pairs of axially chiral emitting enantiomers, flexible (R/S)‐ODQPXZ and rigid (R/S)‐ODPPXZ, are reported by fusing (R/S)‐octahydro‐binaphthol chiral source, diphenyl quinoxaline (DQ)/dibenzo[a,c]phenazine (DP) acceptors and phenoxazine (PXZ) donors. The symmetrical chiral‐acceptor‐donor configuration endows them thermally activated delayed fluorescence (TADF) properties with small singlet–triplet energy gaps of 0.16 and 0.07 eV, high photoluminescence quantum yields of 92% and 89% in doped films, and obvious mirror‐image CPL characteristics, respectively. The CP‐OLEDs based on these TADF enantiomers not only show a maximum external quantum efficiency of 28.3% with yellow emission for (R/S)‐ODQPXZ and 20.3% with orange‐red emission for (R/S)‐ODPPXZ, but also display the CPL with dissymmetry factors (gEL) of 6.0 × 10−4 and 2.4 × 10−3, respectively. The high efficiency and obvious CPL of (R)‐ODPPXZ arise from a synergetic interplay of the TADF skeleton and the rigid coplanar acceptor for efficient chiral induction and suppressed intramolecular rotational quenching. [ABSTRACT FROM AUTHOR]

Summary: This article presents a two‐layered framework to investigate the output synchronization problem in nonhomogeneous agent systems in the presence of periodic energy‐limited denial‐of‐service (DoS) attacks with an event‐triggered control strategy. Under the developed framework, the proposed controller for different agents is composed of a dynamic compensator and a regulator, where the dynamic compensator on the first layer can copy the dynamics of the leader node. DoS attacks with a periodic (partially known) attack strategy are based on a time sequence and interrupt the data exchange over a shard network consisting of the leader node and dynamic compensators in the first layer. An event‐triggered control protocol is proposed to reduce the update frequency of the controller, and it also ensures that the output of every dynamic compensator can track the output of the leader node without occurring "Zeno phenomenon." Based on the output regulator theory, the regulator for every agent can guarantee that all nonhomogeneous agents can converge to the trajectory of every dynamic compensator in the bottom layer. Finally, a simulation example is demonstrated to verify the new design method developed. [ABSTRACT FROM AUTHOR]

To boost intrinsic circularly polarized luminescence (CPL) properties of chiral emitters, an axially chiral biphenyl unit is inlaid in thermally activated delayed fluorescent (TADF) skeleton, urging the participation of chiral source in frontier molecular orbital distributions. A pair of enantiomers, (R)‐BPPOACZ and (S)‐BPPOACZ, containing the cyano as electron‐withdrawing moieties and carbazole and phenoxazine as electron‐donating units are synthesized and separated. The circularly polarized TADF enantiomers exhibit both high photoluminescence quantum yield of 86.10% and excellent CPL activities with maximum dissymmetry factor |gPL| values of almost 10−2 in solution and 1.8 × 10−2 in doped film, which are among the best values of previously reported small chiral organic materials. Moreover, the circularly polarized organic light‐emitting diodes based on the TADF enantiomers achieve the maximum external quantum efficiency of 16.6% with extremely low efficiency roll‐off. Obvious circularly polarized electroluminescence signals with |gEL| values of 4 × 10−3 are also recorded. [ABSTRACT FROM AUTHOR]

Click chemistry focuses on the development of highly selective reactions using simple precursors for the exquisite synthesis of molecules. Undisputedly, the CuI‐catalyzed azide–alkyne cycloaddition (CuAAC) is one of the most valuable examples of click chemistry, but it suffers from some limitations as it requires additional reducing agents and ligands as well as cytotoxic copper. Here, we demonstrate a novel strategy for the azide–alkyne cycloaddition reaction that involves a photoredox electron‐transfer radical mechanism instead of the traditional metal‐catalyzed coordination process. This newly developed photocatalyzed azide–alkyne cycloaddition reaction can be performed under mild conditions at room temperature in the presence of air and visible light and shows good functional group tolerance, excellent atom economy, high yields of up to 99 %, and absolute regioselectivity, affording a variety of 1,4‐disubstituted 1,2,3‐triazole derivatives, including bioactive molecules and pharmaceuticals. The use of a recyclable photocatalyst, solar energy, and water as solvent makes this photocatalytic system sustainable and environmentally friendly. Moreover, the azide–alkyne cycloaddition reaction could be photocatalyzed in the presence of a metal‐free catalyst with excellent regioselectivity, which represents an important development for click chemistry and should find versatile applications in organic synthesis, chemical biology, and materials science. [ABSTRACT FROM AUTHOR]

Summary: The paper investigates the asynchronous H∞ filtering design problem for continuous‐time linear systems with Markov jump. The hidden Markov jump principle is applied to represent the asynchronous situation between the target system and the designed filter. Via a Lyapunov technique, two sufficient conditions are developed to guarantee that the filtering error system is stochastically stable with a prescribed H∞ noise attenuation level. Furthermore, three filtering design approaches are developed in the form of linear matrix inequalities. Finally, one example is provided to show the effectiveness and feasibility of the developed methods. [ABSTRACT FROM AUTHOR]

Pure organic materials with intrinsic room‐temperature phosphorescence typically rely on heavy atoms or heteroatoms. Two different strategies towards constructing organic room‐temperature phosphorescence (RTP) species based upon the through‐space charge transfer (TSCT) unit of [2.2]paracyclophane (PCP) were demonstrated. Materials with bromine atoms, PCP‐BrCz and PPCP‐BrCz, exhibit RTP lifetime of around 100 ms. Modulating the PCP core with non‐halogen‐containing electron‐withdrawing units, PCP‐TNTCz and PCP‐PyCNCz, successfully elongate the RTP lifetime to 313.59 and 528.00 ms, respectively, the afterglow of which is visible for several seconds under ambient conditions. The PCP‐TNTCz and PCP‐PyCNCz enantiomers display excellent circular polarized luminescence with dissymmetry factors as high as −1.2×10−2 in toluene solutions, and decent RTP lifetime of around 300 ms for PCP‐TNTCz enantiomers in crystalline state. [ABSTRACT FROM AUTHOR]

Chiral materials with circularly polarized luminescence (CPL) are potentially applicable for 3D displays. In this study, by decorating the pyridinyl‐helicene ligands with ‐CF3 and ‐F groups, the platinahelicene enantiomers featured superior configurational stability, as well as high sublimation yield (>90 %) and clear CPPL properties, with dissymmetry factors (|gPL|) of approximately 3.7×10−3 in solution and about 4.1×10−3 in doped film. The evaporated circularly polarized phosphorescent organic light‐emitting diodes (CP‐PhOLEDs) with two enantiomers as emitters exhibited symmetric CPEL signals with |gEL| of (1.1–1.6)×10−3 and decent device performances, achieving a maximum brightness of 11 590 cd m−2, a maximum external quantum efficiency up to 18.81 %, which are the highest values among the reported devices based on chiral phosphorescent PtII complexes. To suppress the effect of reverse CPEL signal from the cathode reflection, the further implementation of semitransparent aluminum/silver cathode successfully boosts up the |gEL| by over three times to 5.1×10−3. [ABSTRACT FROM AUTHOR]

Abstract: Multi‐resonance induced by boron and nitrogen atoms in opposite resonance positions endows a thermally activated delayed fluorescence (MR‐TADF) emitter with a strikingly small full width at half maximum of only 26 nm and excellent photoluminescence quantum yield of up to 97.48 %. The introduction of a carbazole unit in the para position of the B‐substituted phenyl‐ring can significantly boost up the resonance effect without compromising the color fidelity, subsequently enhancing the performances of the corresponding pure blue TADF‐OLED, with an outstanding external quantum efficiency (EQE) up to 32.1 % and low efficiency roll‐off, making it one of the best TADF‐OLEDs in the blue region to date. Furthermore, utilizing this material as host for a yellow phosphorescent emitter, the device also shows a significantly reduced turn‐on voltage of 3.2 V and an EQEmax of 22.2 %. [ABSTRACT FROM AUTHOR]

The problem of distributed filtering for discrete‐time periodic non‐linear systems over sensor networks in the presence of jumping uncertainties and unreliable channels is investigated in this study. A random variable which is subject to a Markov chain is introduced to govern the jumping uncertainties. Considering the unreliable channels between the system and filters, a discrete‐time fading model is introduced to describe this channel fading phenomenon with the discrete probability distribution of each channel coefficients known a priori. On the basis of a fixed network topology, by establishing the periodic Lyapunov function, sufficient conditions on the existence of distributed filter are proposed to ensure the stability and dissipativity of the filtering error system. The distributed filter for discrete‐time periodic non‐linear systems is designed via solving a set of linear matrix inequalities. The merits and validity of the proposed design techniques are verified by means of a numerical simulation example. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of finite-time asynchronous [ABSTRACT FROM AUTHOR]

In this work, we propose a dynamic output feedback robust model predictive control (RMPC) design method for linear uncertain systems with input constraints. In order to handle the input constraints, the control signals are permitted to saturate, which can fully utilize the capability of actuators and thus can reduce the conservatism. For the unavailable states, an ellipsoidal set is used to obtain an estimation, and it is updated at every time instant. A modified RMPC design requirement is used to ensure the recursive feasibility of the optimization problem. Then, the design method is formulated in terms of a convex optimization problem with linear matrix inequality constraints. The proposed output feedback RMPC design method is expected to further reduce the conservativeness. The improvements of the proposed algorithm over the other existing techniques is demonstrated by an example. [ABSTRACT FROM AUTHOR]

Two phosphorescent IrIII complexes Ir1 and Ir2 containing 5-fluoro-2-[4-(trifluoromethyl)phenyl]pyrimidine and 2-(3,4-difluorophenyl)-5-fluoropyrimidine as cyclometalated main ligand and tetraphenylimidodiphosphinate as ancillary ligand were synthesized. Ir1 was characterized by single-crystal X-ray crystallography. Ir1 and Ir2 show green emissions peaking at 527 and 513 nm, respectively. By using the two complexes as emitters, organic light-emitting diodes (OLEDs) with the structure of TAPC (1,1-bis[4-(di- p-tolylamino)phenyl]cyclohexane, 40 nm)/ Ir1 or Ir2 (10 wt.-%):mCP (1,3-bis(9 H-carbazol-9-yl)benzene, 20 nm)/TmPyPB (1,3,5-tris( m-pyrid-3-ylphenyl)benzene, 30 nm)/LiF (1 nm)/Al (100 nm) showed high performance with maximum current efficiencies as high as 81.91 or 71.17 cd A-1 and maximum external quantum efficiencies of 20.8 or 21.3 %, respectively. The low-efficiency roll-off ratios of the two devices suggest that the two complexes have potential applications in OLEDs. [ABSTRACT FROM AUTHOR]

This paper investigates the reliable mixed passive and [ABSTRACT FROM AUTHOR]

This study investigates aperiodic sampled‐data synchronisation of complex dynamical network (CDN) incorporate dynamics of actuators saturation. The sampling intervals considered here are time‐varying which allowed to be variable within the lower and upper bounds. In order to fully captures the sawtooth structure characteristic of the sampled‐data systems, a novel time‐dependent continuous Lyapunov functional is employed to obtain less conservative criteria. Furthermore, the generalised sector bound condition is utilised for the estimate about the basin of the attraction. Based on the local stability condition, the sampled‐data controller is constructed to guarantee the synchronisation of CDN in the presence of actuators saturation. The obtained sufficient conditions can be cast in two optimisation cases to maximise the admissible upper bound of sampling instants or enlarge estimate about the domain of attraction for the closed‐loop systems. Subsequently, the validity and applicability of the criteria are verified through numerical examples. [ABSTRACT FROM AUTHOR]

This study is concerned with the non‐fragile mixed ℋ∞ /l2 − l∞ synchronisation control problem for discrete‐time complex networks with Markov jumping‐switching topology under unreliable communication links. The network topology under consideration is assumed to be governed by a Markov chain with time‐varying transition probabilities (TPs). The variation of TPs is subject to a kind of slow switching signals; that is, the average dwell time (ADT) switching. The focus is on the design of non‐fragile mixed mode‐dependent/‐independent controllers such that the underlying network reaches stochastic mean‐square synchronisation with a mixed ℋ∞ /l2 − l∞ performance level for an admissible switching signal with ADT. By using a new mixed ℋ∞ /l2 − l∞ performance index, combined with the switched control method, the solutions to the considered problem are formulated. Finally, simulation results demonstrate the effectiveness of our proposed approach. [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates the problems of stability analysis and stabilization for stochastic time-delay systems. Firstly, this paper uses the martingale theory to investigate expectations of stochastic cross terms containing the Itô integral. On the basis of this, an improved delay-dependent stability criterion is derived for stochastic delay systems. In the derivation process, the mathematical development avoids bounding stochastic cross terms, and neither model transformation method nor free-weighting-matrix method is used. Thus, the method leads to a simple criterion and shows less conservatism. Secondly, on the basis of this stability result, this paper further proposes a state-feedback controller that exponentially stabilizes the stochastic delay system by a strict LMI. Therefore, unlike previous results, it is not necessary to transform the nonlinear matrix inequalities into LMIs by the cone complementarity linearization method or parameter-tuning method, which always yield a suboptimal solution. Finally, examples are provided to demonstrate the reduced conservatism of the proposed conditions.Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study is concerned with the finite‐time energy‐to‐peak filtering problem for Markov jump repeated scalar non‐linear systems with packet dropouts. The packet dropout phenomenon occurs in a random way and is modelled by a stochastic variable satisfying the Bernoulli distribution. The purpose of the study is to design a filter such that the resulting filtering error system is stochastically finite‐time bounded, and a prescribed energy‐to‐peak performance level is achieved over a finite time interval. By using the mode‐dependent diagonally dominant Lyapunov function approach, some strict linear matrix inequality‐based conditions are established for the existence of an admissible filter, and a corresponding explicit parameterisation of such a filter is obtained. Finally, a numerical example with simulation is presented to demonstrate the effectiveness of our proposed approach. [ABSTRACT FROM AUTHOR]

This study is concerned with the problem of the elimination of overflow oscillations (EOOs) for two‐dimensional (2D) digital filters with external interference. The main purpose is the presentation of a new unified criterion such that the underlying 2D digital filter is stable with a positive prescribed interference attenuation level. A performance index is proposed for the first time, which is referred to as generalised dissipativity property. By using this index and two harmonic slack matrices, a novel criterion is established, which can be used to solve ℋ∞ EOOs, passive EOOs and l2 –l∞ EOOs for 2D digital filters with external interference in a unified framework, and reduce the conservatism of the existing results. The effectiveness of the criterion is demonstrated by a numerical example. [ABSTRACT FROM AUTHOR]

This study deals with the problem of finite‐time reliable ℒ2 − ℒ∞ /ℋ∞ control for non‐linear systems with actuator faults through Takagi–Sugeno fuzzy model approach. The actuator failure model under consideration is assumed to be governed by a homogenous Markov chain. The focus is on the design of a fuzzy Markov switching fault‐tolerant controller such that the resulting closed‐loop system is stochastically finite‐time bounded with a mixed ℒ2 − ℒ∞ /ℋ∞ performance level over a finite‐time interval. Some sufficient conditions for the solvability of the above problem are given in terms of linear matrix inequalities by introducing a new mixed ℒ2 − ℒ∞ /ℋ∞ performance function. Finally, a quarter‐vehicle suspension model is employed to demonstrate the effectiveness of our proposed approach. [ABSTRACT FROM AUTHOR]

The problem of chattering free sliding mode control for a class of uncertain discrete singular systems with state delay is investigated in this paper. As a component of the solution, a new least squares support vector machine ( LS- SVM) reaching law is proposed. In terms of linear matrix inequalities, a delay-dependent condition for sliding mode dynamics to be regular, causal, and asymptotically stable is established, and the chattering problem that appears in traditional variable structure systems is eliminated. Numerical examples are provided to demonstrate the applicability of the proposed methods. [ABSTRACT FROM AUTHOR]

The required imines may be prepared in situ, thus affording the products in a sequential three-component reaction. [ABSTRACT FROM AUTHOR]