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This article focuses on solving the secure control problem by developing a novel resilient hybrid learning scheme for discrete-time Markov jump cyber-physical systems with malicious attacks. Within the zero-sum game framework, the secure control problem is converted into solving a set of game coupled algebraic Riccati equations. However, it contains the coupling terms arising from the Markov jump parameters, which are difficult to solve. To address this issue, we propose a framework for parallel reinforcement learning. Thereafter, a model-based resilient hybrid learning scheme is first designed to obtain the optimal policies, where the system dynamics are required during the learning process. Furthermore, a novel online model-free resilient hybrid learning scheme combining the advantages of value iteration and policy iteration is proposed without using the system dynamics. Besides, the convergence of the proposed hybrid learning schemes is discussed. Eventually, the effectiveness of the designed algorithms is demonstrated with the inverted pendulum model.

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BACKGROUND: The Cardiogenic Shock Working Group-modified Society for Cardiovascular Angiography and Interventions (CSWG-SCAI) staging was developed to risk stratify cardiogenic shock (CS) severity. Data showing progressive changes in SCAI stages and outcomes are limited. OBJECTIVES: We investigated serial changes in CSWG-SCAI stages and outcomes of patients presenting with cardiogenic shock complicating acute myocardial infarction (MI-CS) and heart failure-related CS (HF-CS). METHODS: The multicenter CSWG registry was queried. CSWG-SCAI stages were computed at CS diagnosis and 24, 48, and 72 hours. RESULTS: A total of 3,268 patients (57% HF-CS; 27% MI-CS) were included. At CS diagnosis, CSWG-SCAI stage breakdown was 593 (18.1%) stage B, 528 (16.2%) stage C, 1,659 (50.8%) stage D, and 488 (14.9%) noncardiac arrest stage E. At 24 hours, >50% of stages B and C patients worsened, but 86% of stage D patients stayed at stage D. Among stage E patients, 54% improved to stage D and 36% stayed at stage E by 24 hours. Minimal SCAI stage changes occurred beyond 24 hours. SCAI stage trajectories were similar between MI-CS and HF-CS groups. Within 24 hours, unadjusted mortality rates of patients with any SCAI stage worsening or improving were 44.6% and 34.2%, respectively. Patients who presented in or progressed to stage E by 24 hours had the worst prognosis. Survivors had lower lactate than nonsurvivors. CONCLUSIONS: Most patients with CS changed SCAI stages within 24 hours from CS diagnosis. Stage B patients were at high risk of worsening shock severity by 24 hours, associated with excess mortality. Early CS recognition and serial assessment may improve risk stratification.

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A novel reinforcement learning-based predefined-time tracking control scheme with prescribed performance is presented in this article for nonlinear systems in the presence of external disturbances. First, by employing the backstepping strategy, an adaptive optimized controller is developed under the identifier-critic-actor framework. Therein, the unknown nonlinear dynamics and the system control behavior can be learned effectively through neural networks. Moreover, aiming at obtaining the preset tracking performance, the prescribed performance control is integrated with the predefined-time control. In contrast to previous studies, the proposed scheme can not only constrain the tracking error rapidly to a prearranged vicinity of origin, but also ensure that the upper bound of convergence time can be adjusted in advance via a separate control parameter. In terms of the predefined-time stability theory, the boundedness of all system states can be proven within a predefined time. Finally, the availability and improved performances of the proposed control scheme are demonstrated by a numerical example and a single-link manipulator example.

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This study mainly investigates the adaptive leader-following consensus tracking control problem for a class of nonlinear multiagent systems (MASs) subjected to unknown control directions, external disturbances, and sensor deception attacks. To start with, an equivalent MAS with known control directions is obtained by introducing a linear state transformation. For the purpose of estimating the unavailable system states caused by malicious attacks, a quantization-based fuzzy state observer is designed, and the fuzzy-logic system (FLS) is utilized to approximate nonlinear functions. Moreover, a dynamic uniform quantizer with scaling function is established to reduce information transmission. With the help of coordinate transformation and available compromised states, a novel compensation mechanism is designed to offset the influence of filter errors while avoiding the problem of "explosion of complexity" in the backstepping design process. In addition, the Nussbaum-type function is considered to eliminate the design obstacle of unknown control gains resulting from the attacks. Under the constructed consensus protocol, it is proved theoretically that the consensus tracking error converges to an adjustable small neighborhood of the origin, and all signals in the closed-loop system are bounded. Finally, the feasibility of the provided secure control scheme is verified through two simulation examples.

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The model predictive control (MPC)-based asynchronous attack tolerant control scheme is investigated in this article for uncertain Markov jump cyber-physical systems (MJCPSs) under the Denial-of-Service (DoS) attack. To tackle the problem of the system running mode may not be observed in the control center, an asynchronous model predictive controller is proposed. Specifically, a dynamic controller, which can tune the performance online, is designed besides a traditional state feedback one. Even though such a combination may cause possible degradation of system performance, it can expand the initial feasible region and relieve the online computation burden efficiently. In addition, a decision variable is introduced to alleviate limitations on the feasible region generated by the constraints in the traditional MPC method. A series of solvable optimal problems are further constructed to achieve the desired performances. Finally, an application of the proposed method is given to demonstrate its effectiveness.

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This paper investigates a sliding mode control method for a class of uncertain delayed fractional-order reaction-diffusion memristor neural networks. Different from most existing literature on sliding mode control for fractional-order reaction-diffusion systems, this study constructs a linear sliding mode switching function and designs the corresponding sliding mode control law. The sufficient theory for the globally asymptotic stability of the sliding mode dynamics are provided, and it is proven that the sliding mode surface is finite-time reachable under the proposed control law, with an estimate of the maximum reaching time. Finally, a numerical test is presented to validate the effectiveness of the theoretical analysis.

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BACKGROUND: There are limited data depicting the prevalence and ramifications of acute limb ischemia (ALI) among cardiogenic shock (CS) patients. METHODS: We employed data from the Cardiogenic Shock Working Group (CSWG), a consortium including 33 sites. We constructed a multi-variable logistic regression to examine the association between clinical factors and ALI, we generated another logistic regression model to ascertain the association of ALI with mortality. RESULTS: There were 7,070 patients with CS and 399 (5.6%) developed ALI. Patients with ALI were more likely to be female (40.4% vs 29.4%) and have peripheral arterial disease (13.8% vs 8.3%). Stratified by maximum society for cardiovascular angiography & intervention (SCAI) shock stage, the rates of ALI were stage B 0.0%, stage C 1.8%, stage D 4.1%, and stage E 10.3%. Factors associated with higher risk for ALI included: peripheral vascular disease OR 2.24 (95% CI: 1.53-3.23; p < 0.01) and ≥2 mechanical circulatory support (MCS) devices OR 1.66 (95% CI: 1.24-2.21, p < 0.01). ALI was highest for venous-arterial extracorporeal membrane oxygenation (VA-ECMO) patients (11.6%) or VA-ECMO+ intra-aortic balloon pump (IABP)/Impella CP (16.6%) yet use of distal perfusion catheters was less than 50%. Mortality was 38.0% for CS patients without ALI but 57.4% for CS patients with ALI. ALI was significantly associated with mortality, adjusted OR 1.40 (95% CI 1.01-1.95, p < 0.01). CONCLUSIONS: The rate of ALI was 6% among CS patients. Factors most associated with ALI include peripheral vascular disease and multiple MCS devices. The downstream ramifications of ALI were dire with a considerably higher risk of mortality.

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For the flexible riser systems modeled with partial differential equations (PDEs), this article explores the boundary control problem in depth for the first time using a dynamic event-triggered mechanism (DETM). Given the intrinsic time-space coupling characteristic inherent in PDE computations, implementing a state-dependent DETM for PDE-based flexible risers presents a significant challenge. To overcome this difficulty, a novel dynamic event-triggered control method is introduced for flexible riser systems, focusing on optimizing available control inputs. In order to save computational costs from the controller to the actuator, a dynamic event-triggered adaptive boundary controller is designed to effectively reduce boundary position vibrations. Additionally, considering external disturbances, an adaptive bounded compensation term is incorporated to counteract the influence of external disturbances on the system. Addressing boundary position constraints, a new integral barrier Lyapunov function (iBLF) tailored specifically for flexible riser systems is introduced, thereby alleviating conservatism in the controller design of flexible risers modeled by PDEs. At last, the validity of the proposed method is demonstrated through a simulation example.

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This article addresses the finite-time neural predefined performance control (PPC) issue for state-constrained nonlinear systems (NSs) with exogenous disturbances. By integrating the predefined-time performance function (PTPF) and the conventional barrier Lyapunov function (BLF), a new set of time-varying BLFs is designed to constrain the error variables. This establishes conditions for satisfying full-state constraints while ensuring that the tracking error meets the predefined performance indicators (PPIs) within a predefined time. Additionally, the incorporation of the nonlinear disturbance observer technique (NDOT) in the control design significantly enhances the ability of the system to reject disturbances and improves overall robustness. Leveraging recursive design based on dynamic surface control (DSC), a finite-time neural adaptive PPC strategy is devised to ensure that the closed-loop system is semi-globally practically finite-time stable (SPFS) and achieves the desired PPIs. Finally, the simulation results of two practical examples validate the efficacy and viability of the proposed approach.

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This article investigates the stabilization issue of highly non-linear hybrid stochastic delayed networks (HSDNs) via periodic self-triggered control under impulse (PS-TCI). Firstly, the existence of a unique global solution for highly non-linear HSDNs under PS-TCI is studied. Then, a stabilization criterion for highly non-linear HSDNs is established, by combining a graph-theoretic approach with a novel Lyapunov-based analysis, based on a 'genuine' Lyapunov function defined by introducing an auxiliary timer. Therein, the less conservative polynomial growth condition and local Lipschitz condition for the drift and diffusion coefficients are used than the linear growth condition and global Lipschitz condition. Meanwhile, the design idea of PS-TCI is based on the evolution of an upper bound of the mathematical expectation for Lyapunov function (not directly Lyapunov function or system state), which implies that the triggered instant of PS-TCI is not a random variable. Finally the theoretical results are employed to study the stability of a class of FitzHugh-Nagumo circuits networks and the central pattern generators networks of a hexapod robot, and correlative numerical simulations are provided for demonstration.

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This article proposes a novel event-triggered second-order sliding mode (SOSM) control algorithm using the small-gain theorems. The developed algorithm has global event property in aspects of the triggering time intervals. First, an SOSM controller is designed related to the sampling error of states, and it is proved that the closed-loop system is finite-time input-to-state stable (FTISS) with the sampling error via utilizing the small-gain theorems. Second, combined with the constructed SOSM controller, a new triggering mechanism is proposed depending on the sampling error by designing the appropriate FTISS gain condition. Third, the practical finite-time stability of the closed-loop system is verified. It is shown that the minimum triggering time interval is always a positive value in the whole state space. Finally, the simulation results demonstrate the effectiveness of the developed control method.

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BACKGROUND: Consensus recommendations for cardiogenic shock (CS) advise transfer of patients in need of advanced options beyond the capability of "spoke" centers to tertiary/"hub" centers with higher capabilities. However, outcomes associated with such transfers are largely unknown beyond those reported in individual health networks. OBJECTIVES: To analyze a contemporary, multicenter CS cohort with the aim of comparing characteristics and outcomes of patients between transfer (between spoke and hub centers) and nontransfer cohorts (those primarily admitted to a hub center) for both acute myocardial infarction (AMI-CS) and heart failure-related HF-CS. We also aim to identify clinical characteristics of the transfer cohort that are associated with in-hospital mortality. METHODS: The Cardiogenic Shock Working Group (CSWG) registry is a national, multicenter, prospective registry including high-volume (mostly hub) CS centers. Fifteen U.S. sites contributed data for this analysis from 2016-2020. RESULTS: Of 1890 consecutive CS patients enrolled into the CSWG registry, 1028 (54.4%) patients were transferred. Of these patients, 528 (58.1%) had heart failure-related CS (HF-CS), and 381 (41.9%) had CS related to acute myocardial infarction (AMI-CS). Upon arrival to the CSWG site, transfer patients were more likely to be in SCAI stages C and D, when compared to nontransfer patients. Transfer patients had higher mortality rates (37% vs 29%, < 0.001) than nontransfer patients; the differences were driven primarily by the HF-CS cohort. Logistic regression identified increasing age, mechanical ventilation, renal replacement therapy, and higher number of vasoactive drugs prior to or within 24 hours after CSWG site transfer as independent predictors of mortality among HF-CS patients. Conversely, pulmonary artery catheter use prior to transfer or within 24 hours of arrival was associated with decreased mortality rates. Among transfer AMI-CS patients, BMI > 28 kg/m2, worsening renal failure, lactate > 3 mg/dL, and increasing numbers of vasoactive drugs were associated with increased mortality rates. CONCLUSION: More than half of patients with CS managed at high-volume CS centers were transferred from another hospital. Although transfer patients had higher mortality rates than those who were admitted primarily to hub centers, the outcomes and their predictors varied significantly when classified by HF-CS vs AMI-CS.

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PURPOSE: The Impella device historically required a heparin-based purge solution to reduce the risk of biomaterial deposition to maintain pump function. In April 2022, the Food and Drug Administration approved utilization of bicarbonate-based purge solutions (BBPS) as an alternative to heparin for patients who are intolerant to heparin or in whom heparin is contraindicated. The purpose of this case series is to report patient outcomes of Impella support with BBPS use at our institution. SUMMARY: Eighteen patients who received BBPS via the Impella CP or Impella 5.5 device were included in our review. Patients were included if they had BBPS administration for greater than 24 hours. All patients were followed for 72 hours after cessation of BBPS. Indications for BBPS were coagulopathy (n = 5, 28%), suspected HIT (n = 2, 11%), confirmed HIT (n = 1, 6%), and major bleeding (n = 10, 56%). Three patients (17%) experienced an Impella complication while on BBPS. One patient required pump exchange, one required removal of the Impella device, and one received alteplase for suspected purge block. Of these, two patients experienced complications greater than 21 days into BBPS therapy. CONCLUSION: This case series adds to the literature describing clinical outcomes for patients on Impella support with BBPS. While BBPS offers a viable option for the management of patients on Impella devices who are unable to tolerate heparin-based purge solutions, further data is needed to determine the longevity of the Impella device with BBPS to minimize risk of Impella complications.

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When there is a sudden load disturbance in an islanded microgrid, the peer-to-peer control model requires the energy resource to maintain a margin of generation, resulting in a relatively limited regulation range, that is, voltage/frequency sometimes requires additional control to maintain stability. A "source-storage-load" coordinated master-slave control strategy is proposed in this study to address the aforementioned issues. The system voltage and frequency will be stable as long as the output frequency and voltage of the master resource are stable. Furthermore, it can fully utilize the power supply capacity of resources to support the supply-demand balance. The following tasks are included in the proposed strategy: 1) to improve the operational security in the face of load disruption, a source-storage-load coordinated control method based on the "ramping speed" ratio is proposed, which can quickly restore the balance of supply and demand; 2) to improve the communication reliability in the face of interruption, a channel planning method is proposed, which can address the communication interruption problem by constructing an internal network among source-storage-load; and 3) to improve the mode switching stability of resources subjected to external disturbance, the external disturbance suppression and stability analysis involved in the regulation process are completed using sliding-mode control and small signal model methods. Related case studies are carried out to verify the effectiveness of the proposed strategies.

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Airway remodeling is a major pathological characteristic of chronic obstructive pulmonary disease (COPD). This study aimed to investigate the effect of Abhd2 deficiency on ovalbumin (OVA)-induced airway remodeling and inflammation in vivo. Abhd2-deficient mice were used to establish an OVA-induced asthma model. Lung tissues were analyzed using hematoxylin and eosin (HE) staining, Masson staining, immunohistochemistry, quantitative reverse transcription- polymerase chain reaction (qRT-PCR), and western blotting were used to determine the role of Abhd2 in the regulation of OVA-induced airway remodeling and inflammation. Our findings revealed that the RNA expression of inflammatory factors, including IL-1ß, IL-6, IL-4, and IL-13, was significantly increased in OVA-induced Abhd2 Gt/Gt asthmatic mice. The expression of IFN-γ was decreased significantly in OVA-induced Abhd2 Gt/Gt asthmatic mice. The protein expression of airway remodeling factors, including α-SMA, type I collagen, and Ki67, was also increased in OVA-induced Abhd2 Gt/Gt asthmatic mice compared to that in OVA-induced wild-type (WT) mice. Additionally, Abhd2 deficiency promoted the expression of p-Akt in tissues of the asthma model. These results suggest that Abhd2 deficiency exacerbates airway remodeling and inflammation through the PI3K/Akt pathway in chronic asthma.

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Objective: To investigate the impact of relative locations of multiple foci and microsatellite status of sporadic, synchronous, multiple, primary, colorectal carcinomas on clinicopathological features and prognosis. Methods: The clinicopathologic and prognostic data of 278 patients with sporadic, synchronous, multiple, primary, colorectal carcinomas who had been admitted to the Department of Colorectal Surgery at Zhejiang Cancer Hospital from January 2008 to July 2022 were retrospectively collected. The patients were categorized into three groups based on the relative locations of their multiple cancer foci: (1) a right-sided group that comprised patients with multiple cancer foci in the cecum, ascending colon, hepatic flexure of the colon, and transverse colon; (2) a left-sided group that comprised patients with multiple cancer foci in the splenic flexure of the colon, descending colon, sigmoid colon, and rectum; and (3) a left- and right-sided group that comprised patients with multiple cancer foci in the right half of the colon and left half of the colon/rectum. Additionally, the patients were further divided into two groups based on microsatellite status: a high microsatellite instability (MSI-H) and a low MSI/stable MSI (MSI/L&MSS) group. We compared differences in clinical characteristics and prognostic indicators between these groups. The χ2 test was utilized to compare selected clinical characteristics, whereas Kaplan-Meier survival analyses and log-rank tests were performed to compare their effects on prognosis. Result: Among 278 patients with SSCRC, 256 (92.1%) presented with two cancer foci and 22 (7.9%) with more than two foci. Additionally, 255 patients (91.7%) had adenocarcinomas, whereas the remaining 23 (8.3%) had mucinous adenocarcinomas. Lymph node metastases were identified in 136 patients (48.9%); the cancer foci had infiltrated beyond the muscular layer in 238 (85.6%); and 147 patients (52.9%) were diagnosed with TNM Stage III-IV disease. There were 155 patients (55.8%) in the left-sided group, 55 (19.8%) in the right-sided group, and 68 (24.5%) in the left- and right-sided group. Immunohistochemical examination of all four mismatch repair proteins were performed in 199 cases, revealing that 166 of these patients had MSI/L&MSS and 33 MSI-H disease. In the left-sided, left- and right-sided, and right-sided groups, the proportion of women was 16.8% (26/155), 26.5% (18/68), and 49.1% (27/55), respectively; these differences are statistically significant (χ2=22.335, P<0.001). The proportions of patients with more than three cancer foci were 5.2% (8/155), 16.2% (11/68), and 5.5% (3/55), respectively; these differences are statistically significant (χ2=8.438, P=0.015). The proportions of mucinous adenocarcinomas were 4.5% (7/155), 8.8% (6/68), and 18.2% (10/55), respectively; these differences are statistically significant (χ2=10.026, P=0.007). The proportions of patients with lymph node metastases were 55.5% (86/155), 48.5% (33/68), and 30.9% (17/55); these differences are statistically significant (χ2=9.817, P=0.007). The proportions of patients with Stage T3 & T4 disease in each group according to location were 81.3% (126/155), 88.2% (60/68), and 94.5% (52/55), respectively; these differences are statistically significant (χ2=6.293,P=0.043). The proportions of TNM Stage III-IV tumors were 59.4% (92/155), 54.4% (37/68), and 32.7% (18/55), respectively; these differences are statistically significant (χ2=11.637, P=0.003). Age, size of cancer foci, presence of distant metastasis, adenoma, nerve invasion, and vascular invasion did not differ significantly between the three groups (all P>0.05). Compared with those with MSI-H, patients with MSI/L&MSS disease were more likely to be aged >65 years and male (50.6% [84/166] vs. 15.2% [5/33], χ2=13.994,P<0.001; 80.7% [134/166] vs. 54.5% [18/33], χ2=10.457,P=0.001), more likely to be in the left-sided group (63.3% [105/166] vs. 24.2% [8/33], χ2=18.232, P<0.001), had a higher proportion of cancer foci of diameter <4 cm (54.8% [91/166] vs. 33.3% [11/33], χ2=5.086,P=0.024), and a lower proportion of mucinous adenocarcinomas (4.2% [7/166] vs. 27.3% [9/33], χ2=19.791,P<0.001), more likely to develop distant metastases (22.3% [37/166] vs. 6.1% [2/33], χ2=4.601,P=0.032), more likely to have lymph node metastases (57.2% [95/166) vs. 24.2% [8/33], χ2=11.996,P<0.001) and nerve invasion (28.9% [48/166] vs. 6.1% [2/33], χ2=7.643, P=0.006), had a higher proportion of TNM Stage III-IV disease (60.2% [100/166] vs. 24.2% [8/33], χ2=14.374, P<0.001), and a smaller proportion of family history of tumors (28.9% [48/166] vs. 60.6% [20/33], χ2=12.228, P<0.001). All the above-listed differences are statistically significant (all P<0.05). The differences in number of cancer foci, depth of infiltration, presence or absence of adenomas, and vascular invasion were not statistically significant (all P>0.05). In the 33 patients with MSI-H status and mismatch repair protein loss, the highest frequency of deletion was found in PMS-2 (66.7%, 22/33), followed by MLH-1 (57.6%, 19/33), whereas the proportions of MSH-2 (33.3%, 11/33) and MSH-6 (24.2%, 8/33) deletions were relatively low. There were statistically significant differences in the 3-year overall survival rates among the groups according to relative locations of cancer foci. The 3-year overall survival rates were 96.8%, 79.6%, and 88.5% in the right-sided, left- and right-sided, and left-sided groups, respectively (P=0.021). As to microsatellite status, the 3-year overall survival rate of patients with MSI-H disease was 93.8%, which is significantly better than the 78.4% for those with MSI/L & MSS (P=0.026). Conclusions: Among sporadic, synchronous, multiple, primary, colorectal carcinomas, those with right-sided disease had the deepest local infiltration, whereas those with left-sided disease had the greatest number of lymph node metastases, most advanced clinical TNM stage, lowest percentage of MSI-H disease, and the poorest prognosis.

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BACKGROUND: Studies reporting cardiogenic shock (CS) outcomes in women are scarce. OBJECTIVES: The authors compared survival at discharge among women vs men with CS complicating acute myocardial infarction (AMI-CS) and heart failure (HF-CS). METHODS: The authors analyzed 5,083 CS patients in the Cardiogenic Shock Working Group. Propensity score matching (PSM) was performed with the use of baseline characteristics. Logistic regression was performed for log odds of survival. RESULTS: Among 5,083 patients, 1,522 were women (30%), whose mean age was 61.8 ± 15.8 years. There were 30% women and 29.1% men with AMI-CS (P = 0.03). More women presented with de novo HF-CS compared with men (26.2% vs 19.3%; P < 0.001). Before PSM, differences in baseline characteristics and sex-specific outcomes were seen in the HF-CS cohort, with worse survival at discharge (69.9% vs 74.4%; P = 0.009) and a higher rate of maximum Society for Cardiac Angiography and Interventions stage E (26% vs 21%; P = 0.04) in women than in men. Women were less likely to receive pulmonary artery catheterization (52.9% vs 54.6%; P < 0.001), heart transplantation (6.5% vs 10.3%; P < 0.001), or left ventricular assist device implantation (7.8% vs 10%; P = 0.01). Regardless of CS etiology, women had more vascular complications (8.8% vs 5.7%; P < 0.001), bleeding (7.1% vs 5.2%; P = 0.01), and limb ischemia (6.8% vs 4.5%; P = 0.001). More vascular complications persisted in women after PSM (10.4% women vs 7.4% men; P = 0.06). CONCLUSIONS: Women with HF-CS had worse outcomes and more vascular complications than men with HF-CS. More studies are needed to identify barriers to advanced therapies, decrease complications, and improve outcomes of women with CS.

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In this paper, the exponential consensus of leaderless and leader-following multi-agent systems with Lipschitz nonlinear dynamics is illustrated with aperiodic sampled-data control using a two-sided loop-based Lyapunov functional (LBLF). Firstly, applying input delay approach to reformulate the resulting sampled-data system as a continuous system with time-varying delay in the control input. A two-sided LBLF which captures the information on sampled-data pattern is constructed and the symmetry of the Laplacian matrix together with Newton-Leibniz formula have been employed to obtain reduced number of decision variables and decreased LMI dimensions for the exponential sampled-data consensus problem. Subsequently, an aperiodic sampled-data controller was designed to simplify and enhance stability conditions for computation and optimization purposes in the proposed approach. Finally, based on the controller design, simulation examples including the power system are proposed to illustrate the theoretical analysis, moreover, a larger sampled-data interval can be acquired by this method than other literature, thereby conserving bandwidth and reducing communication resources.

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This work investigates the protocol-based synchronization of inertial neural networks (INNs) with stochastic semi-Markovian jumping parameters and image encryption application. The semi-Markovian jumping process is adopted to characterize INNs under sudden complex changes. To conserve the limited available network bandwidth, an adaptive event-driven protocol (AEDP) is developed in the corresponding semi-Markovian jumping INNs (S-MJINNs), which not only reduces the amount of data transmission but also avoids the Zeno phenomenon. The objective is to construct an adaptive event-driven controller so that the drive and response systems maintain synchronous relationships. Based on the appropriate Lyapunov functional, integral inequality, and free weighting matrix, novel criteria are derived to realize the synchronization. Moreover, the desired adaptive event-driven controller is designed under a semi-Markovian jumping process. The proposed method is demonstrated through a numerical example and an image encryption process.

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In this paper, the stochastic sampled-data exponential synchronization problem for Markovian jump neural networks (MJNNs) with time-varying delays and the reachable set estimation (RSE) problem for MJNNs subjected to external disturbances are investigated. Firstly, assuming that two sampled-data periods satisfy Bernoulli distribution, and introducing two stochastic variables to represent the unknown input delay and the sampled-data period respectively, the mode-dependent two-sided loop-based Lyapunov functional (TSLBLF) is constructed, and the conditions for the mean square exponential stability of the error system are derived. Furthermore, a mode-dependent stochastic sampled-data controller is designed. Secondly, by analyzing the unit-energy bounded disturbance of MJNNs, a sufficient condition is proved that all states of MJNNs are confined to an ellipsoid under zero initial condition. In order to make the target ellipsoid contain the reachable set of the system, a stochastic sampled-data controller with RSE is designed. Eventually, two numerical examples and an analog resistor-capacitor network circuit are provided to show that the textual approach can obtain a larger sampled-data period than the existing approach.

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