Event-based multi-objective filtering for multi-rate time-varying systems with random sensor saturation

summary:This paper focuses on the multi-objective filtering of multirate time-varying systems with random sensor saturations, where both the variance-constrained index and the $H_\infty$ index are employed to evaluate the filtering performance. According to address issues, the high-frequency period of the internal state of the system is nondestructively converted to the low-frequency period, which determined by the measurement devices. Then the saturated output of multiple sensors is modeled as a sector bounded nonlinearity. At the same time, in order to reduce the communication frequency between sensors and filters, a communication scheduling rule is designed by the utilization of an event-triggered mechanism. By means of random analysis technology, the sufficient conditions are given to guarantee the preset $H_\infty$ performance and variance constraint performance indexes of the system, and then the solution of the desired filter is obtained by using linear matrix inequalities. Finally, the validity and effectiveness of the proposed filter scheme are verified by numerical simulation

Antiurolithiatic effect of ferulic acid on ethylene glycolinduced renal calculus in experimental rats

Purpose: To evaluate the anti-urolithiatic effect of ferulic acid on ethylene glycol-induced kidney stone in a rat model.Methods: Five groups of adult male Sprague-Dawley rats (6 rats/group) were used in this study. Group I rats served as normal control. Renal calculus was induced through ethylene glycol (0.75 % v/v in drinking water) administration to all rats for 28 days except those in group 1. Prior to ethylene glycol treatment, ferulic acid was given orally (gavage) to rats in groups III and IV at doses of 40 and 80 mg/kg, respectively. Rats in group V (positive control) were treated with standard drug, cystone at a dose of 750 mg/kg prior to ethylene glycol administration, while group II rats received no treatment. Kidney tissue and blood serum were sampled after 28 days and used for biochemical and histopathological analyses.Results: Rats in group II showed significant increases in oxidative stress pattern as seen in significant reductions in GSH, SOD, GPx, and CAT levels, and significant elevation of lipid peroxidation (LPO), relative to normal control group (p < 0.05). However, renal calculus formation and oxidative stress were significantly inhibited by ferulic acid treatment in groups III and IV. These results were supported by histopathological findings.Conclusion: Ferulic acid exerts anti-urolithiatic effect via inhibition of oxidative stress. Thus, it has potentials for use in preventing kidney stone formation.Keywords: Urolithiasis, Ferulic acid, Ethylene glycol, Kidney, Histopatholog

Stability analysis and controller synthesis of continous-time linear time-delay systems

published_or_final_versionMechanical EngineeringDoctoralDoctor of Philosoph

Fully Distributed Event-Triggered Consensus of Double-Integrator Multi-Agent Systems

In this paper, the consensus problem is studied for double-integrator multi-agent systems with edge-based event-triggered communication. More specifically, two agents connected by an edge mutually sample the relative state information when a designed triggering condition is satisfied. The triggering mechanism is introduced to reduce the communication frequency. To make the triggering mechanism implementable, a positive minimum inter-event time is guaranteed in all communication links in the network. All designs use only local neighborhood information. Based on Lyapunov analysis, the proposed algorithm makes all the agents converge to a consensus trajectory asymptotically

Stabilization for state/input delay systems via static and integral output feedback

This paper addresses the static and integral output feedback stabilization problems of continuous-time linear systems with an unknown state/input delay. By combining an augmentation approach and the delay partitioning technique, criteria for static and integral output feedback stabilizability are proposed in terms of nonlinear matrix inequalities with a free parameter matrix introduced. These new characterizations possess a special structure, which leads to linearized iterative computation. The effectiveness and merits of the proposed approach are shown through numerical example

Stability and stabilization for Markovian jump time-delay systems with partially unknown transition rates

This paper focuses on the stability analysis and controller synthesis of continuous-time Markovian jump time-delay systems with incomplete transition rate descriptions. A general stability criterion is formulated first for state- and input-delay Markovian jump time-delay systems with fully known transition rates. On the basis of the proposed condition, an equivalent condition is given under the assumption of partly known/unknown transition rates. A new design technique based on a projection inequality has been applied to design both state feedback and static output feedback controllers. All conditions can be readily verified by efficient algorithms. Finally, illustrative examples are provided to show the effectiveness of the proposed approach