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Modern controller design is increasingly based on data-driven control methods. PID controllers are still used primarily in the industry, because they are Linear Quadratic Regulator (LQR). The LQR provides an efficient way to tune the parameters of a PID controller. The LQR has the disadvantage of requiring accurate models of the system, as well as reducing a high-order system to a second-order model. First, we explore the new horizons of control theory in the form of the state-space model for high nonlinear systems. Second, the Lagrangian method establishes the new mathematical model of the two-stage linear inverted pendulum system. In addition, real-time LQR parameters are calculated under variable load. This method has been demonstrated to be highly applicable and accurate through simulations and experiments using the Double Inverted Pendulum model. [ABSTRACT FROM AUTHOR]

This paper presents a state feedback control design with an event-triggered scheme for the Maglev Train (MagT.) system with a saturated control input. In a state feedback control design that precisely tracks the position of the coil current and coil voltage of actuated levitation system, we first derived the mathematical model in the form of a state–space model from the MagT. model; then, we implemented the saturated control input to encounter the uncertainties. A new event-triggered mechanism, in which the threshold parameter remains constant with resulting states, is utilized to save the constrained network resources and improve information exchange efficiency. Using the Lyapunov–Krasovskii functional method, a defensive control is established in the form of linear matrix inequalities (LMIs) for the resultant system. Finally, it is shown through the most practical approach example that the proposed method in this paper is effective for ensuring better system performance. [ABSTRACT FROM AUTHOR]

The aim of this paper is to admit and stabilize T–S descriptive with time delays. We present some general conditions for the uniqueness and existence in terms of the impulse-free solution for delayed T–S fuzzy systems. Thus, we establish and obtain in terms of strict linear matrix inequalities new sufficient conditions for the stability of T–S fuzzy systems and delayed T–S fuzzy systems by constructing the Lyapunov–Krasovskii functional and applying the generalized Itô formula. Furthermore, a novel algorithm for real-time adjustment of controller membership functions is designed based on a gradient descent strategy to obtain superior H ∞ performance. By using non-PDC fuzzy control mechanism instead of conventional non-PDC control scheme, the performance of interference reduction can be effectively improved. [ABSTRACT FROM AUTHOR]

In this study, we present a novel fuzzy control strategy that considers the influence of lead times on nonlinear supply chain management (SCM) systems. The authors have constructed a fuzzy control model for an SCM model based on nonlinear phenomena with lead times, drawing inspiration from Takagi-Sugeno's (T-S) fuzzy control system. Additionally, the authors have designed a fuzzy H ∞ control approach to mitigate the effects of lead times, switch between sub-models, and address customers' stochastic requests, all while considering the concept of maximal overlapped rules groups. The control of nonlinear supply chain management is implemented in a manner that ensures asymptotic stability and facilitates smooth transitions from one subsystem to another. The introduction of the membership function into the fuzzy system results in reduced fluctuations in the system's variables. The key contributions of the research include the design of a fuzzy H ∞ control approach, leveraging maximal overlapping-rules group (MRRG) to ensure stability through localized definite positive matrices identification. This strategy achieves two primary objectives: asymptotic stability of the supply chain system and smooth switching between nonlinear SCM elements. The authors demonstrate the effectiveness of their proposed method through comprehensive comparisons with the fuzzy H ∞ control technique. The study provides a valuable insight into managing lead times in SCM through dynamic and stable control methodologies. Finally, a comprehensive comparison is provided between the suggested H ∞ management approach and the fuzzy H ∞ control strategy. This comparison is demonstrated through two-stage nonlinear numerical simulations, keeping SCM lead times in mind. Movement results are presented to illustrate the effectiveness of our suggested algorithm. • A fuzzy control for mitigating the effects of lead times. • Considering stochastic demands from customers. • MRRG in T-S fuzzy system linked to control ensures stability. • Proposed control ensures smooth switching in nonlinear supply chain elements. • Linked to fuzzy H_∞ control, our method is paralleled for effective demonstration. [ABSTRACT FROM AUTHOR]

In this paper, the mechanism for estimation of the sensor and actuator faulty control problem for the class of nonlinear systems is investigated. First, we transformed the nonlinear system into a new coordinate system to estimate the fault. In the new coordinate system, the Lipschitz conditions and system uncertainties are also considered. Then, by implementing the sliding mode observer (SMO) method, initially, we introduced the transformation scheme to make the system rational. In this, we split our system into two parts such that the actuator fault function had only occurred in the second state vector of nonlinear dynamics. Based on the Lyapunov stability theory and appropriate inequality, some sufficient criteria in the form of linear matrix inequalities are obtained to ensure the bounded stability for the prescribed H ∞ performance level. In addition, the designed algorithm for actuator fault is further applied for sensor fault. Finally, the numerical example with simulation results is provided to validate the practicability and efficacy of the developed control strategy. [ABSTRACT FROM AUTHOR]

In this article, an adaptive event‐triggered fault detection problem for the asynchronous Takagi–Sugeno fuzzy networked Markov jump systems is investigated based upon the time‐varying delays. The purpose of designing a fault detection filter is to detect the fault signal under the influence of disturbance with network transmission. In the design process, one essential factor, time‐varying delay in the fuzzy filter with appearing in the residual signal, is taken into consideration. In order to rationally utilise network resources and elaborately avoid unnecessary continuous monitoring, an adaptive event‐triggered scheme is designed to guarantee the Takagi–Sugeno fuzzy networked Markov jump systems. Thus it helps to lower the energy consumption of communication while ensuring the performance of the system. Different from the conventional triggering mechanism, in this article, the parameters of the triggering function are based on a new adaptive law which is obtained online rather than a predefined constant. Based on the associated Lyapunov stability theory and appropriate inequality, some sufficient criteria in the form of linear matrix inequalities are obtained to ensure the stability of the resulting error system. Finally, a tunnel diode example is employed to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

This article concerns the event‐triggered fuzzy filter design for Takagi‐Sugeno (T‐S) fuzzy systems subject to deception attacks under the stochastic multiple time‐varying delays. A sequence of random variables, which are mutually independent but obey the Bernoulli distribution, is introduced to account for the randomly occurring communication delays. In order to efficiently utilize limited network communication bandwidth resources, the event‐triggering scheme is adopted. A fuzzy filter with the attacked input signal is presented. Moreover, due to communication delays caused by event‐triggering schemes and transmission, the filter adopts non‐synchronous premise variables with the system. Then, by utilizing a model transformation technique, the fuzzy systems are developed. Furthermore, using the piecewise Lyapunov functional method technique, the resulting criterion provides sufficient conditions to ensure that fuzzy systems under deception attacks are stochastically stable with an H∞ performance. Accordingly, the conditions for the co‐design of the fuzzy filter and event‐triggering schemes are given. Finally, numerical simulation with the industrial process provided to verify the proposed event‐triggered design. [ABSTRACT FROM AUTHOR]

This paper deals with reliable, robust fuzzy filtering problem with random time delays characterized by uncertain Takagi–Sugeno (T–S) fuzzy singular systems. The singular systems are presented as T–S fuzzy singular systems, which gives a more realistic representation for a variety of nonlinear dynamical systems than usual state-space models.The proposed scheme is designed for uncertain T–S fuzzy singular systems with linear fractional parametric uncertainties. The delay in the filtering system is supposed to be random. The interim and parameter uncertainties are measured with a linear fractional transformation structure. Furthermore, another intention of this article is to establish the filters containing network communication delays with uncertainties under the sensor fault. To construct the fuzzy singular filters with these considerations, a new version of fuzzy Lyapunov–Krasovskii functional is implemented for the performance and stability analysis of the resultant error. Linear matrix inequalities characterize original stability conditions. The effectiveness of the proposed algorithm is validated by an example of the DC motor application. [ABSTRACT FROM AUTHOR]

In this article, we investigate a new way of dealing with fault detection and isolation (FDI) for a class of delayed non‐linear systems with an event‐triggered mechanism (ETM). This article is based on 1) To estimate the dynamics of the nonlinear plant, Sliding Mode Observers (SMO's) is manipulated with Luenberger. 2) Under the ETM, sampled data is released only when the plant's measurement (sampled) violate the specific threshold of the event condition. 3) First, transform into two subsystems. In subsystem‐A contains uncertainties without sensor fault and vice‐versa in subsystem‐B. To handle the uncertainties that appeared in subsystem‐A, a new SMO's implemented while traditional Luenberger is employed to detect the sensor fault. Then, by using a new Lyapunov‐Krasovskii function approach performance index is proposed. Based on stability criteria, sufficient conditions are provided in the account of Linear Matrix Inequalities (LMIs). The simulation example is given to demonstrate the effectiveness of our design method. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of quantized state feedback H∞ control for T-S fuzzy systems with appearing the communication delay under stochastic nonlinearity. To accomplish the objective a uniform framework for effective bandwidth utilization is employed to design co-design method. First of all, the co-design method is proposed such that the data can be communicated according to some logic function. Then, we implemented the measurement size-reduction scheme, using the logarithmic quantization. Additionally, we provided the impact of co-design method and quantization, on the original model of networked control systems (NCSs) is redeveloped as a new structure of hybrid-triggered NCSs with network induced delay. Moreover, Lyapunov-Krasovskii functional is considered to grantee the closed-loop for stochastic stability analysis of the T-S fuzzy system. The solvability of Lyapunov-Krasovskii functional results in the formation of Linear matrix inequalities. The solution of Linear matrix inequalities leads to the controller gains to perform simulations to validate the proposed scheme. [ABSTRACT FROM AUTHOR]

Summary: This paper is focused on reliable controller design for a composite‐driven scheme of networked control systems via Takagi‐Sugeno fuzzy model with probabilistic actuator fault under time‐varying delay. The proposed scheme is distinguished from the other schemes as mentioned in this paper. Aims of this article are to solve the control problem by considering the H∞, dissipative, and L2−L∞ constraints in a unified way. Firstly, to improve the efficient utilization of bandwidth, the adaptive composite‐driven scheme is introduced. In such a scenario, the channel transmission mechanism can be adjusted between adaptive event‐triggered generator scheme and time‐driven scheme. In this study, the threshold is dependent on a new adaptive law, which can be obtained online rather than a predefined constant. With a constant threshold, it is difficult to get the variation of the system. Secondly, a novel fuzzy Lyapunov‐Krasovskii functional is constructed to design the fuzzy controller, and delay‐dependent conditions for stability and performance analysis of the control system are obtained. Then, LMI‐based conditions for the existence of the desired fuzzy controller are presented. Finally, an inverted pendulum that is controlled through the channel is provided to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of fuzzy filter design for a class of delayed nonlinear system under random sensor faults with an event-triggered (ET) mechanism. (1) To estimate the dynamics of nonlinear plant, a T–S fuzzy model is manipulated. Random variables are disclosed to express the sensor fault. (2) To take some advantages over existing one, a variable ET mechanism is offered in networked systems (NSs). Under the ET mechanism, sensor data are released only when the plant's measurement (sampled) violate specific threshold of the event condition. (3) Another purpose of this article is to design filters involving system state delays. Then, by using a novel fuzzy Lyapunov–Krasovskii function approach with free weighting matrix technique, dissipative filter design of ET delay networked control systems is proposed. We consider both the sensor fault and ET scheme simultaneously. The simulation example is given to demonstrate the effectiveness of design method. [ABSTRACT FROM AUTHOR]

This article presents the results on delay-dependent conditions of extended quantized T–S fuzzy filtering based on Markovian switch system (Q-FMSS) in the existence of communication delays via a channel. Different from the existing fuzzy filter, a new fuzzy filter is proposed to receive not only the quantized output of the system but also gets the quantized delay output. The purpose of this paper is to solve the H ∞ , L 2 - L ∞ , passive and dissipative filtering problems. The extended dissipative inequality contains several weighting matrices. By tuning the weighting matrices, the extended dissipativity will reduce to the H ∞ performance, L 2 - L ∞ performance, passivity and dissipativity, respectively. Another drive of this paper is to fully investigate the properties of Transition Rates (TRs) of Markovian switch system with Membership Function (MF) by implementing the novel fuzzy Markovian Lyapunov–Krasovskii functional to obtain the sufficient LMI conditions (delay dependent) for stochastically stability and performance analysis of resulting error system. Extended dissipativity notation is employed to resolve the resulting error system to consider the H ∞ , L 2 - L ∞ , dissipativity and passivity analyses, which are important for the power systems. Finally, a tunnel-diode example is given to elaborate the potentiality and effectiveness of the proposed design technique. [ABSTRACT FROM AUTHOR]

This paper focuses on the design of H ∞ filter and event-triggered scheme for a class of continuous non-linear networked control systems (NCSs) based on fuzzy system appeared with time delays. First, we consider the discrete event-triggered (ET) scheme to make efficient utilisation of bandwidth. Under this ET-scheme, sensor releases the data only when our sampled-data plant violates the specific event-triggered condition. Second, the T-S fuzzy system is used to model the non-linear NCSs. Another purpose of this paper is to design filters involving delays. Such filters have a more general form than the delay-free filters that have been mostly considered in the traditional studies. By using the time-delay system, co-design of event-triggered scheme and H ∞ filter for the delayed NCSs is presented in a unified frame work. To choose the latest data packet and discard the dis-ordered packet logic, zero-order hold is inserted between the fuzzy filter and event generator. Then, by using the novel fuzzy Lyapunov-Krasovskii function approach with free-weighting matrix technique, H ∞ filter design of event-triggered delay NCSs is proposed. Finally, to show the effective result of our co-design method, a tunnel-diode example is given. [ABSTRACT FROM AUTHOR]

This research presents a practical study of active disturbance rejection control law (ADRC) for the control of robotic manipulators in the presence of uncertainties. The control objective of the proposed control law is to track the trajectory accurately and rejects the disturbance caused by robotic manipulators. First, Euler Lagrange's equations are used to model the dynamic behavior of a rotary flexible joint manipulator system (RFJMS). Secondly, the ADRC is designed for the rejection of lump disturbances (modeling uncertainties, nonlinearities, and external disturbances) of the manipulator; to estimate the lump disturbances a fifth-order extended state observer is constructed. Furthermore, a state error feedback control law with disturbance compensation is designed, which needs only a few control parameters to be adjusted. Furthermore, we demonstrate the robustness and effectiveness of the proposed control law by comparing the experimental results with those of LQR and PID. Experimental results show that high precision position control as well as vibration suppression can be achieved with the proposed controller, which is superior to LQR and PID controllers. In spite of uncertainties and nonlinearity of the flexible joint, QUANSER's RFJMS exhibits excellent tracking behavior and disturbance rejection. [ABSTRACT FROM AUTHOR]

Global health, as well as worldwide development regimes, was seriously threatened by the COVID-19 pandemic and Delta variant outbreaks. In addition to pledging to adapt to and mitigate climate change, experts, economists, and policymakers expressed their determination to do so. Green growth and sustainable development have become the focus of policymakers and governments. The progress toward green economic efficiency (GEE), which will benefit the economy, society, and environment, continues. In terms of green growth and development, implementing environmental regulations and policies has been one of the most challenging aspects of the process. China, the world's second-largest economy, has begun its journey to GEE. Nonetheless, the green economy faces many challenges. The objective of the study is to use AHP analysis to analyze environmental regulation and GEE in China. Accordingly, the study identified three alternative approaches to achieve GEE by analyzing four criteria and ten sub-criteria in the context of environmental regulations in China. The analytical hierarchy process (AHP) has been used to rank criteria, sub-criteria, and alternative approaches. According to the model, China's best path to GEE is through resource efficiency and green purchasing strategies. This article offers an insightful assessment of sustainable development in the Chinese economy. [ABSTRACT FROM AUTHOR]

Mobile Health (mHealth) applications play an essential role in healthcare. The usage of mHealth apps is rapidly increasing, and it provides services, such as vitals, medication, and appointments, to patients and physicians. These apps significantly ease for patients to manage their health. Using sensitive health information and communication channels by mHealth apps has potential privacy and security hazards for patient's privacy and security. mHealth apps are primarily dependent on a remote server online. Someone can monitor, alter, and divert communication through public infrastructure. Many mHealth applications did not utilize any encryption method for client–server communication, making it an imminent risk for patients' data security and privacy. In this study, we proposed a framework to develop the mHealth application and apply the security parameters to reduce the risk of data breaches, such as data confidentiality, integrity, and availability. Also, the study aims to identify the transport layer security issues relevant to the client–server of mHealth apps. To test the health data subset of Android and iOS apps collected from their Play Store and evaluate client security by the Charles Proxy tool. At the end of the paper, we presented the principal results of how many apps have vulnerabilities concerned with transport security. We compared our results for the transport layer of SSL and TLS certificates and chipper suit strength to show the performance of our proposed framework. [ABSTRACT FROM AUTHOR]