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In this article, an extended state observer‐based finite‐region control scheme is presented for two‐dimensional Markov jump systems with unknown mismatched disturbances. The mathematical model of the two‐dimensional Markov jump systems is built on the well‐known Roesser model. By establishing special recursive formulas and utilizing the 2‐D Lyapunov function theory, sufficient conditions are obtained, which prove that the resultant system is finite‐region bounded, if some linear matrix inequalities are achieved. Then, we provide an algorithm to solve the extended state observer‐based controller gains. With the proposed control scheme, the external disturbances can be actively rejected from the system outputs. To conclude, a numerical example based on the Darboux equation is provided to demonstrate the validity and effectiveness of the devised control scheme. [ABSTRACT FROM AUTHOR]

This article concerns the admissibility analysis of singular time-delay systems. The aim is to get superior criteria in both low conservativeness and less decision variables. To this end, the systems are decomposed and treated with different methods. The Lyapunov–Krasovskii functionals (LKFs) are constructed based on the state decomposition. By using tighter integral inequalities and the free weighting matrix method, some new admissibility criteria are derived to compare with the previous results, and are applied to the partial element equivalent circuits (PEECs) in numerical examples, by which the advantages of the proposed method are verified. [ABSTRACT FROM AUTHOR]

This article focuses on the finite-time asynchronous output feedback control scheme for a class of Markov jump systems subject to external disturbances and nonlinearities. The conic-type nonlinearities hold a constraint condition which locates in a known hyper-sphere with an indefinite center. In addition, the asynchronization phenomenon occurs between the system and the controller, which can be represented by means of a hidden Markov model. A sufficient condition is derived not only to guarantee the finite-time boundedness of the acquired closed-loop systems but also to possess a desired $H_{\infty }$ performance on the basis of Lyapunov functional technique. Finally, the validity and feasibility of the proposed method are demonstrated with a dc-motor experiment. [ABSTRACT FROM AUTHOR]

This article study the asynchronous control problem for a class of discrete-time Markovian jumping Lur’e systems (MJLSs) over the finite-time interval. The partial accessibility of system modes with respect to the designed controller is described by a hidden Markov model (HMM). The asynchronous control law consists of two parts, i.e., the states and the nonlinearities involved in the dynamics of the controlled system. By selecting the appropriate Lyapunov functional and applying the modified sector condition, the finite-time stabilization conditions under the control constraints are derived. Finally, the effectiveness of the designed method is verified by an illustrative simulation. [ABSTRACT FROM AUTHOR]

This paper is concerned with the sliding mode control (SMC) via finite-time stabilization (FTS) for a class of conic-type nonlinear semi-Markovian jumping systems (SMJSs). Comparing with the classical Markovian jumping systems, the transition rates of SMJSs are related to the random sojourn-time $g$. Based on this, a suitable SMC law for driving the state trajectories to the designed sliding surface within a finite-time interval is given. Then, the FTS over reaching phase and sliding motion phase is further proved to guarantee the FTS of the whole SMJSs. Finally, the effectiveness of the proposed method is demonstrated by a time-delayed Chua’s circuit simulation. [ABSTRACT FROM AUTHOR]

This paper studies the $ {H}_{ {\infty }}$ sliding mode control (SMC) problem for a class of discrete-time conic-type nonlinear systems with time-delays and uncertainties. The nonlinear terms satisfy the conic-type constraint condition that lies in a know hyper-sphere with an uncertain center. By choosing a proper Lyapunov candidate, sufficient conditions are derived to ensure the asymptotic stability of the sliding mode dynamics while achieving a prescribed $ {H}_{ {\infty }}$ disturbance attenuation level and finally converted into a minimization problem. The controller is constructed to guarantee the discrete-time reach condition and maintain the states on the prespecified sliding surface. A simulation result and a practical example related to the Chua’s circuit are given at last to show the validity of our SMC strategy. [ABSTRACT FROM AUTHOR]

Summary: Joint estimation of states and time‐varying parameters of linear stochastic systems is of practical importance for fault diagnosis and fault tolerant control. The known fact is that measurements have outliers. They can significantly degrade the properties of linearly recursive algorithms, which are designed to work in presence of Gaussian noises. This article proposes two kinds of strategies for joint parameter‐state robust estimation of linear stochastic models in presence of all possible faults and non‐Gaussian noises. In the form of Theorem, joint robust algorithm for systems with sensor and component faults, as well as the algorithm for systems with parameter faults are proposed. Because of their good features in robust filtering, Masreliez‐Martin filter represents a cornerstone for realization of the proposed robust algorithms for joint state‐parameter estimation. The good features of proposed robust estimation algorithms, in relation to algorithms based on other widely‐used filters, are illustrated by simulation results. On the other side, intensive research in the field of mathematical modeling of pneumatic servo drives has shown that their mathematical models are nonlinear in which a lot of important details cannot be included in the model. Also, it has been well known that the nonlinear model can be approximated by a linear model with time‐varying parameters. Due to the abovementioned reasons, it can be assumed that the pneumatic cylinder model is a linear stochastic model with variable parameters. The good practical values of the proposed robust joint algorithm to identification of the pneumatic cylinder are illustrated by experimental results. [ABSTRACT FROM AUTHOR]

In this paper, an online adaptive optimal control problem of a class of continuous-time Markov jump linear systems (MJLSs) is investigated by using a parallel reinforcement learning (RL) algorithm with completely unknown dynamics. Before collecting and learning the subsystems information of states and inputs, the exploration noise is firstly added to describe the actual control input. Then, a novel parallel RL algorithm is used to parallelly compute the corresponding N coupled algebraic Riccati equations by online learning. By this algorithm, we will not need to know the dynamic information of the MJLSs. The convergence of the proposed algorithm is also proved. Finally, the effectiveness and applicability of this novel algorithm is illustrated by two simulation examples. [ABSTRACT FROM AUTHOR]

An observer‐based finite‐time asynchronous H∞ control law is designed for a class of hidden Markov jumping systems with non‐linearities and external disturbances. The non‐linearities satisfy the conic‐type constraint condition that lies in a known hypersphere with an uncertain centre. The non‐synchronisation phenomenon between the system modes and observer/controller modes is modelled by a hidden Markov model. By means of the proper stochastic Lyapunov–Krasovskii functional method, a sufficient condition is obtained to guarantee the stochastic finite‐time boundedness of the corresponding argument error dynamic systems with a satisfied H∞ disturbance rejection level. Finally, the feasibility and validity of the main results is illustrated through a pratical example related to the DC motor. [ABSTRACT FROM AUTHOR]

The finite‐time stabilisation for a class of time‐delayed Markovian jumping systems with conic nonlinearities is studied. The authors aim to design a suitable control law to stabilise the closed‐loop system during a specified finite time. An appropriate Lyapunov–Krasovskii functional method is given to ensure the existence of finite‐time stabilisation controller and the relevant sufficient conditions have been formulated in the form of linear matrix inequalities. Finally, a simulation example is given to show the effectiveness of the proposed design approach. [ABSTRACT FROM AUTHOR]

This paper investigates the asynchronous resilient controller design problem for a class of nonlinear switched systems with time-delays and uncertainties in a given finite-time interval. By constructing proper multiple Lyapunov–Krasovskii functions and applying average dwell time methods, a switching law and the relevant asynchronous resilient controller are designed to guarantee the finite-time boundedness of the closed-loop system with a specified ${H} _{\infty }$ performance index. The ${H} _{\infty }$ resilient controller design problems can be derived by solving a set of linear matrix inequalities. A practical example is employed to demonstrate the availability of the proposed methods. [ABSTRACT FROM AUTHOR]

The finite-time sliding mode controller design problem of a class of conic-type nonlinear systems with time-delays and mismatched external disturbance is studied. The time-delay conic nonlinearities are considered to lie in a known hypersphere with an uncertain center. A scalar selection criterion dependent sliding mode control (SMC) law is constructed to drive the state trajectories onto the specified sliding surface during any assigned short time interval. By using slack matrix approach, a delay-dependent sufficient condition is derived to ensure the finite-time boundedness of the closed-loop systems over the finite-time interval. Then, the algorithm for designing the finite-time SMC law is established. Finally, two examples related to the time-delayed Chua’s circuit is given to demonstrate the effectiveness of the developed methods. [ABSTRACT FROM AUTHOR]

Key message: The mutated LsTT2 and Ls2OGD genes are responsible for white seeds and yellow seeds in lettuce, respectively. Three LsCHS genes are involved in the biosynthesis of flavonoid in seed coats. Lettuce seeds have several different colors, including black, yellow, and white. The genetic mechanisms underlying color variations of lettuce seeds remain unknown. We used genome-wide association studies (GWAS) and map-based cloning approaches to clone genes controlling the color of lettuce seeds. LsTT2, which encodes an R2R3-MYB transcription factor and is homologous to the TT2 gene in Arabidopsis, was shown to be the causal gene for the variation of black and white seeds in lettuce. A point mutation leads to the lack of stop codon in the LsTT2 transcript, resulting in white seeds. Knockout of the LsTT2 gene converted black seeds to white seeds. The locus controlling yellow seeds was mapped to Chromosome 2. Knockout of two 2-oxoglutarate-dependent dioxygenases (2OGD) genes from the candidate region converted black seeds to yellow seeds, suggesting that these two 2OGD proteins catalyze the conversion of yellow metabolites to black metabolites. We also showed that three LsCHS genes from the candidate region are associated with flavonoid biosynthesis in seeds. Knockout mutants of the three LsCHS genes decreased color intensity. This study provides new insights into the regulation of flavonoid biosynthesis in plants. [ABSTRACT FROM AUTHOR]

A new online iterative algorithm for solving the H ∞ control problem of continuous-time Markovian jumping linear systems is developed. For comparison, an available offline iterative algorithm for converging to the solution of the H ∞ control problem is firstly proposed. Based on the offline iterative algorithm and a new online decoupling technique named subsystems transformation method, a set of linear subsystems, which implementation in parallel, are obtained. By means of the adaptive dynamic programming technique, the two-player zero-sum game with the coupled game algebraic Riccati equation is solved online thereafter. The convergence of the novel policy iteration algorithm is also established. At last, simulation results have illustrated the effectiveness and applicability of these two methods. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This studies the infinite horizon optimal control problem for a class of continuous‐time systems subjected to multiplicative noises and Markovian jumps by using a data‐driven policy iteration algorithm. The optimal control problem is equivalent to solve a stochastic coupled algebraic Riccatic equation (CARE). An off‐line iteration algorithm is first established to converge the solutions of the stochastic CARE, which is generalised from an implicit iterative algorithm. By applying subsystems transformation (ST) technique, the off‐line iterative algorithm is decoupled into N parallel Kleinman's iterative equations. To learn the solution of the stochastic CARE from N decomposed linear subsystems data, an ST‐based data‐driven policy iteration algorithm is proposed and the convergence is proved. Finally, a numerical example is given to illustrate the effectiveness and applicability of the proposed two iterative algorithms. [ABSTRACT FROM AUTHOR]

• The H ∞ fault-tolerant control scheme is studied for a class of conic-type nonlinear Markov jump systems with sensor and actuator faults. • The hidden Markov model is introduced to deal with the asynchronous phenomenon, and the H ∞ fault-tolerant controller is designed by selecting suitable Lyapunov-Krasovskii functional. • The proposed control strategy can not only ensure the finite-time boundedness of the closed-loop system, but also guarantee the required H ∞ performance. This paper studies the H ∞ fault-tolerant control problem for a class of conic-type nonlinear Markov jump systems with sensor and actuator faults as well as unknown disturbances. Firstly, the hidden Markov model is introduced to deal with the asynchronous problem existing in the control systems. By selecting suitable Lyapunov-Krasovskii function, linear matrix inequalities techniques are applied to obtain the H ∞ fault-tolerant controller. A new condition of the state feedback H ∞ fault-tolerant controller with actuator faults and sensor faults is presented. The proposed control strategy can not only ensure the finite-time boundness of the closed loop system, but also guarantee the required H ∞ performance. Lastly, the availability of the design scheme is validated by a simulation example. [ABSTRACT FROM AUTHOR]

This paper studies the robust finite-time energy-to-peak filtering problem for a class of uncertain nonlinear Markovian jumping systems (MJSs) with energy constraint external disturbances. The Takagi–Sugeno (T–S) fuzzy model is employed to represent the nonlinear MJSs. By selecting the appropriate Lyapunov–Krasovskii functional, a sufficient condition is derived such that the filtering error dynamic fuzzy MJSs are finite-time stable and have a prescribed level of L 2 – L ∞ disturbance attenuation in a finite time-interval. The sufficient condition on the existence of robust finite-time energy-to-peak fuzzy filtering criterion is formulated in the form of linear matrix inequalities and the designed finite-time energy-to-peak fuzzy filter is described as an optimization one. A numerical example is given to illustrate the effectiveness of the proposed design approach. [ABSTRACT FROM AUTHOR]

The finite-time passive control for a class of nonlinear uncertain systems with time-delays and uncertainties is studied. The nonlinear parameters are satisfied Lipschitz conditions. An optimal robust passive controller with respect to the finite-time interval is designed while the exogenous disturbances are unknown but energy bounded. Based on passive control theory, the sufficient condition for the existence of finite-time robust passive controller is given. This condition such that the resulting closed-loop system is finite-time boundedness (FTB) for all admissible uncertainties and satisfies the given passive control index. By using the constructed Lyapunov function, and applying linear matrix inequalities techniques (LMIs), the design method of the finite-time optimal passive controller is derived and can be obtained. Simulation results demonstrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]

This study studies the online adaptive optimal control problems for a class of continuous‐time Markov jump linear systems (MJLSs) based on a novel policy iteration algorithm. By utilising a new decoupling technique named subsystems transformation, the authors re‐construct the MJLSs and a set of new coupled systems composed of N subsystems are obtained. The online policy iteration algorithm was used to solve the coupled algebraic matrix Riccati equations with partial knowledge regarding to the system dynamics, and the relevant optimal controllers equivalent to the investigated MJLSs are designed. Moreover, the convergence of the novel policy iteration algorithm is also established. Finally, a simulation example is given to illustrate the effectiveness and applicability of the proposed approach. [ABSTRACT FROM AUTHOR]

The finite-time H ∞ control problem of a class of Lipschitz nonlinear system with parameter uncertainties is studied. The nonlinear parameters are considered to satisfy the quasi-one-sided Lipschitz condition. By using Lyapunov function approach and linear matrix inequality techniques, a state feedback controller is designed to guarantee that the resulted closed-loop system is finite-time bounded and satisfies a given H ∞ constraint condition. And the designed algorithm is described as an optimization one. Simulation results illustrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]

The paper deals with the problem of non-fragile observer-based passive control for a class of Markovian jumping systems (MJSs) subjected to uncertainties, nonlinearities and time-delays. Based on the Takagi–Sugeno fuzzy models, the dynamics of mode-dependent non-fragile state observer and feedback controller system and the combined closed-loop fuzzy dynamic MJSs are constructed. A sufficient condition for passivity and stochastic stability of the combined system is derived and proved by means of the Lyapunov–Krasovskii functional methods and linear matrix inequalities (LMIs) techniques. The non-fragile passive controller and observer parameters can be solved directly by using the existing LMIs optimization techniques. Finally, a numerical simulation is given to illustrate the performance of the proposed approach. [ABSTRACT FROM AUTHOR]

The observer-based finite-time passive control problem of a class of Lipschitz nonlinear systems with uncertainties and time delays is studied. The nonlinear parameters are considered to satisfy the global Lipschitz conditions and the exogenous disturbances are unknown but energy-bounded. By constructing an appropriate Lyapunov function, a observer-based state feedback controller is designed to guarantee that the resulting closed-loop system is finite-time bounded and satisfies the given passive constraint condition. Some sufficient conditions for the solution to this problem are derived in terms of linear matrix inequalities. Simulation results illustrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: The unbiased H ∞ filtering problem is considered for a class of Markov jump systems (MJSs) with distributed time-delays. Based on the selected Lyapunov–Krasovskii functional, it gives a sufficient condition for the existence of the mode-dependent unbiased H ∞ filter such that the filtering error dynamic MJSs is stochastically stable and satisfies a prescribed level of H ∞ disturbance attenuation in an infinite time-interval. The design criterions are presented in the form of linear matrix inequality techniques, and then are described as the optimization problems. At last, two numerical examples are employed to illustrate the effectiveness of the developed techniques. [Copyright &y& Elsevier]

This paper focuses on the issue of the finite-region H ∞ asynchronous control scheme, which is devoted to the transient behavior of a class of two-dimensional Markov jump systems. The disquisitive system is characterized based upon a Roesser model. Considering the fact that there exists an asynchronous phenomenon between the controlled plant and the controller, we introduce a hidden Markov model to address the non-synchronization. By resorting to a given conditional probability matrix, the mode jumps between the controlled plant and the controller are determined. To conclude, an example is employed to illustrate the potential applications of the devised approach. [ABSTRACT FROM AUTHOR]

In this paper, we consider the stochastically finite-time L 2 control problem for a class of positive stochastic Poisson jump systems (PSPJSs). By introducing a novel mode decoupling technique, some necessary and sufficient conditions are given to guarantee the stochastic finite-time boundedness of the input-free PSPJSs. Then, a proper mode-dependent finite-time state feedback controller is designed such that the positiveness, stochastic finite-time boundedness and the specified L 2 disturbance attenuation performance are attained simultaneously for the closed-loop SPJSs. Finally, two examples are given to show the feasibility and validity of the proposed methods. [ABSTRACT FROM AUTHOR]

The popular leafy vegetable lettuce (Lactuca sativa L.) is susceptible to cold stress during the growing season, which slows growth rate, causes leaf yellowing and necrosis, and reduced yield and quality. In this study, transcriptomic and metabolomic analyses of two cold-resistant lettuce cultivars (GWAS-W42 and F11) and two cold-sensitive lettuce cultivars (S13K079 and S15K058) were performed to identify the mechanisms involved in the cold response of lettuce. Overall, transcriptome analysis identified 605 differentially expressed genes (DEGs), including significant enrichment of genes involved in the flavonoid and flavonol (CHS, CHI, F3H, FLS, CYP75B1, HCT, etc.) biosynthetic pathways related to oxidation–reduction and catalytic activity. Untargeted metabolomic analysis identified fifteen flavonoid metabolites and 28 other metabolites potentially involved in the response to cold stress; genistein, quercitrin, quercetin derivatives, kaempferol derivatives, luteolin derivatives, apigenin and their derivatives accumulate at higher levels in cold-resistant cultivars. Moreover, MYBs, bHLHs, WRKYs and Dofs also play positive role in the low temperature response, which affected the expression of structural genes contributing to the variation of metabolites between the resistant and sensitive. These results provide valuable evidence that the metabolites and genes involved in the flavonoid biosynthetic pathway play important roles in the response of lettuce to cold stress. [ABSTRACT FROM AUTHOR]

• Fault detection scheme for conic nonlinear systems in finite frequency domain is designed. • Sufficient conditions to realize H_ fault sensitivity and H_ disturbance attenuation. • The fuzzy fault detection problem is transformed into an optimization algorithm. • A tunnel diode-circuit is given to confirm the validity of the designed scheme. In this paper, we focused on the issue of fault detection subject to a class of conic-type nonlinear systems in the finite frequency domain (FFD). Applying Takagi Sugeno (T-S) fuzzy models, the conic-type dynamic error system is established. To prove that the residual vector is robust to external disturbances and sensitive to faults, we provide some conditions to realize H − fault sensitivity performance and H ∞ disturbance attenuation performance within the FFD. Then, utilizing linear matrix inequalities techniques, the fuzzy fault detection observer design problem is transformed into an optimization algorithm. Finally, a numerical example related to a tunnel diode-circuit is given to confirm the validity of the designed scheme. [ABSTRACT FROM AUTHOR]

This paper addresses finite-time boundedness and stabilization problem for n -neuron uncertain positive Markovian jumping neural networks (MJNNs). Firstly, we analyze the positive MJNNs in the input-free case and then propose a sufficient condition to ensure the input-free finite-time boundedness. Then applying the state feedback scheme, a suitable finite-time stabilizable controller is devised to guarantee the positiveness of the closed-loop MJNNs. Moreover, some sufficient conditions for the existence of the controller gain solutions are proposed and proved by using the stochastic Lyapunov-Krasovskii functional approach and linear matrix inequalities techniques. Finally, we give two simulation examples to demonstrate the effectiveness and feasibility of the proposed methods. [ABSTRACT FROM AUTHOR]

In this paper, a new online adaptive optimal controller design scheme is studied for a class of nonlinear systems with input time-delays. First, we linearize the original nonlinear systems by means of linear differential inclusion technique. Then the adaptive optimal controller of the linearized systems with input time-delays is obtained by online policy iteration algorithm. It also proves the convergence of the designed adaptive optimal control algorithm. Finally, the effectiveness of the proposed method is verified by two simulation examples. [ABSTRACT FROM AUTHOR]

This work addresses a time‐sensitive coverage control problem for multiple non‐holonomic mobile robots. The coverage objective is evaluated by the total arrivial time of robots reaching their dominant clients with the predefined constant but heterogeneous velocities. An extremum‐seeking control framework is proposed, including a numerical optimizer that iteratively produces the optimal waypoints of robots minimizing the total arriving time and a state regulator that drives the robot's positions to the optimal locations under both constraints non‐holonomic kinematic model and the constant‐velocity. An improved K‐means algorithm is first designed to produce the waypoint sequence. A theoretical analysis of the convergence of coverage objectives is provided. Then a fixed‐time state regulator for the robot's angular velocity is derived from regulating robot positions to the desired waypoints within each time step that varies with the heterogeneous traversing velocity and the distance between waypoints. Finally, the results are validated by a virtual robotic simulation platform and the experiment on real robots, showing that the proposed methods can efficiently deploy multiple heterogeneous robots for time‐sensitive services to clients with a discrete distribution. The simulation and experimental code are open‐sourced at https://gitee.com/ahu‐icip/simulation.git. [ABSTRACT FROM AUTHOR]

In this paper, the novel fluorescence probe XP based on Schiff-base was designed, synthesized and characterized, which could detect Y3+selectively and sensitively. The recognition mechanism of XP toward Y3+ was studied by Job's plot and HRMS. It was investigated that stoichiometric ratio of the probe XP conjugated with Y3+ was 1:2. And the detection limit was calculated as 0.30 μM. In addition, Y3+ was recognized by the test paper made from XP. And the probe XP could detect Y3+ selectively in Caenorhabditis elegans and the main organs of mice. Thus, XP was considered to have some potential for application in bioimaging. [ABSTRACT FROM AUTHOR]

Based on the two-dimensional (2D) Roesser model, this paper focuses on the asynchronous controller design for directional 2D Markov jump systems (MJSs). Considering the more practical situation that the modes of the 2D MJSs in the horizontal and vertical directions are independent, and the system modes are asynchronous with that of the controller, the directional 2D MJSs are proposed and the asynchronous controller is designed, respectively. Based on the Lyapunov theory, a sufficient condition for the mean square exponential stability of the controlled directional 2D MJSs is given. Moreover, the partially unknown transition probabilities in systems and controllers are considered. Finally, an example is given to illustrate that the proposed method is effective. [ABSTRACT FROM AUTHOR]

In this paper, we aim to investigate the exponential stability of general hybrid stochastic functional differential systems with delayed impulses. By using the average impulsive interval and the Lyapunov function method, we derive some sufficient conditions for exponential stability, which are less conservative than those existing results based on the supremum or infimum of impulsive interval and more convenient to be applied than those Razumikhin-type conditions in the literature. Meanwhile, we show that unstable hybrid stochastic delay differential systems, both linear and nonlinear, can be stabilized by suitably impulsive sequence. Finally, two examples are discussed to illustrate the effectiveness and advantages of the obtained results. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper concerns the issue of finite-time dissipative asynchronous output feedback control for a wind turbine system that can be modelled as Markov jump Lur'e systems. Due to quantisation, time delays and ubiquitous data dropouts, the actual controller modes in practical application cannot always operate synchronously with the plant modes. To conquer this difficulty, a hidden Markov model is employed to provide some estimated modes information for controlling. In addition, by the Lyapunov function approach and linear matrix inequality technology, sufficient conditions are developed to guarantee finite-time boundedness of the continuous-time closed-loop system subject to strictly (U , G , V) -α-dissipative performance. Finally, a simulation example of a wind turbine system is given to verify the correctness and applicability of the proposed controller. [ABSTRACT FROM AUTHOR]

This paper addresses finite-region asynchronous H ∞ filtering for a class of two-dimensional Markov jump systems (2-D MJSs). A mathematical model is established using the Roesser model, and asynchrony is accounted for using a hidden Markov model (HMM). The modes jumping between the target system and the designed filter are determined by the given conditional probability matrix. Sufficient conditions are derived using suitable Lyapunov function and linear matrix inequalities (LMIs) to ensure stable filtering performance. The practical applicability of the approach is illustrated by two examples. Overall, this study offers a method to tackle filtering challenges in 2-D Markov jump systems, incorporating HMM, Lyapunov functions, and LMIs to effectively solve the finite-region asynchronous H ∞ filtering problem. • An HMM is used to describe the asynchronous phenomenon between the system and the filter. • Lyapunov functional and recursive formulas effectively analyze the FRB of filtering error system. • The Darboux equation and the heat exchange process both validate the effectiveness of the filter. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problems of finite-time H 2 / H ∞ control for linear stochastic Markovian jump systems (SMJSs) suffered from external disturbance and both Brownian motion and Poisson jumps. First, with the help of operator spectrum, a necessary and sufficient condition is given for the exact observability of SJMSs with Brownian motion and Poisson jumps, which is utilized to design observer-based controller. Second, a new differential inequality is constructed and the mode-dependent parameter approach (MDPA) is adopted, to obtain some less conservative results for the existence of state feedback and observer-based feedback finite-time H 2 / H ∞ controllers. Compared with the common parameter approach, the advantages of MDPA are clearly shown. Moreover, H 2 cost function under observer-based feedback proposed in this paper further considers the estimation errors on the basis of the states and estimations, which is more accurate than previous H 2 cost function. Third, two new design algorithms are proposed. One is to search the ranges of some design parameters, and the other is to show the relationship between H 2 and H ∞ performance indices. Finally, a detailed design example is given to illustrate the merits of the proposed results. [ABSTRACT FROM AUTHOR]

In this paper, a novel scheme for the tracking problem of nonlinear systems is proposed. First, as a new technology of neural network in control field, linear differential inclusion is used to approximate the nonlinear term for the entire system. Based on the equivalent linear system, tracking reference signal is given and a new augmented system is built. According to the mentioned value function, two reinforcement learning algorithms are proposed to design the optimal control law. Notice that the online algorithm does not involve the system dynamics and tracking dynamics. In the simulation section, the model of trolley system is given to prove the effectiveness and accuracy of the scheme proposed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, the state estimation problem for singularly perturbed switched complex dynamic networks (CDNs) is addressed, in which the persistent dwell-time (DT) switching mechanism is employed to depict the switchings among parameters of each node. In the aforementioned switching mechanism, the concept of stage consisting of the persistent portion and the DT portion is introduced. Based on the singular perturbation theory, a two-time-scaling variables containing fast and slow states are taken into account on the CDNs simultaneously, which make the constructed networks more realistic. Furthermore, the main aim is to design a mode-dependent estimator to track the state information that cannot be directly obtained and further ensures the global uniform exponential stability of the investigated systems with a generalized dissipativity property. Some sufficient criteria on the existence of the desired mode-dependent state estimator are established by utilizing a modified matrix decoupling method. Finally, the availability of the estimator design procedures is verified by a simulation example. [ABSTRACT FROM AUTHOR]

This paper aims to solve the sliding mode control issue for the discrete nonlinear two-dimensional (2D) Fornasini–Marchesini second (FMII) model under the influence of quantisation error and stochastic packet loss. Firstly, an innovative stochastic 2D FMII sliding mode control model is constructed by considering quantisation error and Bernoulli packet loss process. And then we study the stability issue and formulate the corresponding stability criterion by virtue of the 2D sliding mode surface and a 2D sliding mode control law with data compensation. Subsequently, the reachability for the 2D sliding surface is verified by a innovative and executable 2D sliding mode control law. Besides, the article also formulates the adaptive intelligent iterative algorithms for the sliding mode surface gain and 2D sliding mode control algorithm, respectively. To conclude the paper, an example is provided to analyse its SMC problem under quantisation and stochastic packet loss. This example also shows the effectiveness of the theorems and algorithms proposed in this paper. [ABSTRACT FROM AUTHOR]

A 2-year field experiment was conducted to analyze the growth conditions, physical features, yield, and nitrogen use efficiency (NUE) of sugar-beet under limited irrigation conditions in northeast of China. A cultivar H003 was used as plant materials; six treatments (C1–C6) were included: C1, no nitrogen applied, rain-fed; C2, nitrogen (120.00 kg ha−1), rain-fed; C3, no nitrogen applied, hole irrigation for seeding; C4, nitrogen (120.00 kg ha−1), hole irrigation for seeding; C5, no nitrogen applied, hole irrigation for seeding; and C6, nitrogen (120.00 kg ha−1), hole irrigation for seeding, and irrigation at foliage rapid growth stage. The irrigation supply was only 500 mL/plant once. Results showed C6 showed the highest chlorophyll content, dry matter accumulation, yield, etc. and had the best NUE among all the treatments. In conclusion, under the routine fertilization conditions of northeast of China, the cultivation measure of hole irrigation 500 mL/plant for seeding combined with irrigation 500 mL/plant at foliage rapid growth stage greatly improved sugar-beet yield and NUE. [ABSTRACT FROM AUTHOR]

An online adaptive optimal control problem for a class of nonlinear Markov jump systems (MJSs) is studied. It is worth noting that the dynamic information of MJSs is partially unknown. Applying the neural network linear differential inclusion techniques, the nonlinear terms in MJSs are approximately converted to linear forms. By using subsystem transformation schemes, we can transfer the nonlinear MJSs to N new coupled linear subsystems. Then a new online policy iteration algorithm is put forward to obtain the adaptive optimal controller. Some theorems are given afterward to ensure the convergence of the new algorithm. At last, a simulation example is provided to verify the applicability of the algorithm. [ABSTRACT FROM AUTHOR]

For a class of conic‐type non‐linear time‐delay Markov jump systems, the asynchronous dissipative output feedback controller based on the guaranteed cost control and quantiser is designed in this study. In real applications, the system and the controller modes are always non‐synchronous, so we introduce the hidden Markov model to solve this problem. Furthermore, we define three novel auxiliary variables and use quantisers to accomplish the output feedback controller design. Then, the finite‐time boundedness and strict dissipativity of the closed‐loop systems are guaranteed by sufficient conditions, and the controller also meets the guaranteed cost‐control performance. By solving a set of linear matrix inequalities, we get the controller gains, the guaranteed cost control performance index J*, and the dissipative performance index α. Finally, the correctness and feasibility of this designed approach are demonstrated by a given example. [ABSTRACT FROM AUTHOR]

It's important to pay great attention to the detection of CN− due to its high toxicity. Based on ESIPT characteristics, we design, synthesize and characterize the colorimetric and fluorescence "turn-on" probe AHAM to recognize CN−, which has the large Stokes shift (228 nm), exhibits high sensitivity and excellent selectivity. The limit detection of the probe AHAM for CN− was 1.94 × 10−8 M, which was much lower than the standard set by WHO and many previously reported probes. The recognition mechanism between AHAM and CN− was investigated by spectroscopic analysis, 1H NMR titration and mass spectrometry. To our surprise, AHAM could not only identify CN− reversibly, but also recognize CN− accurately in test paper and silica gel plate applications. Furthermore, AHAM was successfully used for fluorescence imaging in C. elegans and mice. It provides the new easy, fast and accurate method to detect CN−. [Display omitted] • The Stokes shift of AHAM toward CN− reached 228 nm. • AHAM recognized CN− with low LOD selectively, sensitively and reversibly. • AHAM achieved to visualize CN− in C. elegans and mice. [ABSTRACT FROM AUTHOR]

The asynchronous resilient observer design problem for a class of non‐linear switched systems with time‐delays and uncertainties in a given finite‐time interval is studied here. By constructing appropriate multiple Lyapunov–Krasovskii functions and applying the average dwell‐time method, the switching law and the asynchronous resilient observer are designed to guarantee the finite‐time boundedness of the augment system with a specified H∞ performance. The resilient observer design problems can be derived to solve a set of linear matrix inequalities. A numerical simulation is employed to demonstrate the availability of the proposed methods. [ABSTRACT FROM AUTHOR]

Summary: Anthocyanins protect plants from biotic and abiotic stressors and provide great health benefits to consumers. In this study, we cloned four genes (Red Lettuce Leaves 1 to 4: RLL1 to RLL4) that contribute to colour variations in lettuce. The RLL1 gene encodes a bHLH transcription factor, and a 5‐bp deletion in some cultivars abolishes its function to activate the anthocyanin biosynthesis pathway. The RLL2 gene encodes an R2R3‐MYB transcription factor, which was derived from a duplication followed by mutations in its promoter region. The RLL3 gene encodes an R2‐MYB transcription factor, which down‐regulates anthocyanin biosynthesis through competing with RLL2 for interaction with RLL1; a mis‐sense mutation compromises the capacity of RLL3 to bind RLL1. The RLL4 gene encodes a WD‐40 transcription factor, homologous to the RUP genes suppressing the UV‐B signal transduction pathway in Arabidopsis; a mis‐sense mutation in rll4 attenuates its suppressing function, leading to a high concentration of anthocyanins. Sequence analysis of the RLL1‐RLL4 genes from wild and cultivated lettuce showed that their function‐changing mutations occurred after domestication. The mutations in rll1 disrupt anthocyanin biosynthesis, while the mutations in RLL2, rll3 and rll4 activate anthocyanin biosynthesis, showing disruptive selection for leaf colour during domestication of lettuce. The characterization of multiple polymorphic genes in this study provides the necessary molecular resources for the rational breeding of lettuce cultivars with distinct levels of red pigments and green cultivars with high levels of health‐promoting flavonoids. [ABSTRACT FROM AUTHOR]

• An ETS is proposed to reduce energy consumption. • An event-triggered-based controller is designed for MJCPSs. • The uniform upper/lower bounds are used to describe DoS attacks. • Sufficient conditions are given to stabilize the MJCPSs. This paper is concerned with the event-triggered-based H ∞ control problem for Markov jump cyber-physical systems against denial-of-service attacks. The uniform upper and lower bounds are used to describe the characteristics of aperiodic denial-of-service attacks. An event-triggered scheme is introduced to reduce the waste of resources and avoid communication channel congestion. Based on multi-Lyapunov functions, sufficient conditions are proposed to guarantee the asymptotic mean-square stability and H ∞ performance of the switched closed-loop Markov jump cyber-physical systems. By solving linear matrix inequalities, the event-triggered-based controller gain matrices, and H ∞ performance index are obtained. In the simulation, an F-404 aircraft engine system is employed to clarify the validity of the proposed event-triggered-based controller design approach in face of denial-of-service attacks. [ABSTRACT FROM AUTHOR]

This paper presents an integrated self-triggered control strategy with convergence guarantees for model-free continuous-time systems using reinforcement learning. To consider the control cost and triggering consumption in the self-triggered scheme simultaneously, an integrated cost function is proposed. With this integrated cost function, the trade-off between the triggering occupation and control performance could be adjusted according to different requirements. Then, the actor-critic framework of reinforcement learning is employed to learn the control inputs and triggering intervals by minimizing the corresponding integrated cost function. Considering the divergent characteristics between the control inputs and triggering intervals, two different actors are utilized to learn the triggering strategy and control policy, respectively. Also, the convergence of the developed model-free self-triggered control learning algorithm is proved to ensure the limited learning duration of both the control policy and triggering strategy. The proposed framework can be used to design self-triggered controllers for a wide range of engineering systems with unknow dynamics, including control of aircraft, robots, chemical processes, and other automated systems. Finally, the effectiveness and superiorities of the proposed method are verified by an illustrative example. [ABSTRACT FROM AUTHOR]

Cytosolic phospholipase A2alpha (cPLA2α) is a key mediator of tumorigenesis. In this study, by using a combination of pharmacological and genetic approaches in cell models and patient samples, we identify cPLA2α as a selective target to increase chemosensitivity in cervical cancer. We found that transcript and protein levels of cPLA2α but not other forms of cPLA2 (e.g., cPLA2β and cPLA2αδ) were consistently increased in all tested malignant cervical cancer cells and tissues compared to normal counterparts, suggesting that cPLA2α upregulation is a common feature in cervical cancer. We further found that promoting growth and survival rather than invasion were the predominant roles of cPLA2α on cervical cancer. In addition, chemotherapeutic agents achieved ~100% inhibition efficacy in cPLA2α-depleted cervical cancer cells, demonstrating the important role of cPLA2α in chemoresistance. Importantly, we identify that β-catenin is critically involved in the molecular mechanism of cPLA2α's action in cervical cancer. In summary, our work demonstrates the multiple essential roles of cPLA2α in cervical cancer, particularly in chemoresistance, via a β-catenin-dependent manner. Our work also suggests that targeting cPLA2α has a therapeutic value in overcoming chemoresistance in cervical cancer or other cPLA2α-regulated cancers. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of finite-time H∞ resilient filtering for a class of switch systems. The filtering error dynamics is constructed based on the H∞ resilient filter. The objective is to design a filter such that the finite-time H∞ gain from the unknown input to an estimation error is minimized or guaranteed to be less than or equal to a prescribed value. By selecting the proper multiple Lyapunov function and using the average dwell-time approach, sufficient conditions are obtained for the existence of the desired H∞ resilient filter, which also guarantee the finite-time boundedness of the filtering error dynamic systems. The design criteria are proposed in the form of linear matrix inequalities and then described as an optimization algorithm. Finally, a numerical example is employed to illustrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]