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Byline: Biswamohan. Mishra, Ankit. Sachan, Chandrasekhar. Bal, Achal. Srivastava, Amlesh. Seth, Anubhav. Narwal, Mehar. Sharma, Seema. Kaushal, Anoop. Saraya, Awadh. Pandit Sir, A 43-year-old male without any co-morbidity presented with [...]

This article discusses a quantiser-based stabilisation problem for uncertain nonlinear systems with the aid of robust $ \mathcal {[K, KL]} $ [ K , KL ] sector. We confirmed that the quantised-feedback control steers the state trajectories of the uncertain nonlinear systems within the robust $ \mathcal {[K, KL]} $ [ K , KL ] sector in finite time by adjusting the quantisation parameters. Furthermore, control-Lyapunov functions are helpful to obtain sufficient conditions for ensuring the closed-loop system's asymptotic stability and the reachability of the robust $ \mathcal {[K, KL]} $ [ K , KL ] sector. Finally, a nonlinear electronic circuit is provided to test the effectiveness of the designed control law. [ABSTRACT FROM AUTHOR]

This article is concerned with the problem of stabilising nonlinear uncertain systems subject to signal quantisation using nonlinear sector design. The boundary of nonlinear sector decided by the behaviour of the system showing an input-to-state stability is equivalent to $ \mathcal {KL} $ K L -stability. A novel control design based on supervisory-based quantised hands-off control is introduced. With this, the true state of the nonlinear plant is estimated and the quantised control steers the trajectory of the system inside the nonlinear sector in finite time and further to the origin asymptotically. The proposed approach is validated through an illustrative example to demonstrate its theoretical effectiveness. [ABSTRACT FROM AUTHOR]

Introduction: Abnormal levels of heavy metals (HM) and trace elements (TE) affect body metabolism and can induce carcinogenesis. This study aims to evaluate the role of HM and TE in carcinoma urinary bladder (CAUB). Methods: Patients with biopsy-proven CAUB (n = 100) were taken as the study group, while age-and sex-matched healthy volunteers were taken as control (n = 100). Blood and urine samples were compared for Arsenic (As), Copper (Cu), Manganese (Mn), Selenium (Se), Cadmium (Cd), Lead (Pb), and Mercury (Hg) levels. Serum glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and lipid peroxidation (LPO) levels were assessed to know the redox status between the two groups. Results: A significantly higher blood level of As, Mn, and Pb was observed in CAUB cases as compared to controls. Blood Se level was significantly lower in CAUB patients. On comparing urinary levels, CAUB patients had a higher As, Mn, and Pb levels compared to controls. Further, 68% and 59% of patients had their blood and urinary HM and TE levels above the permitted level, respectively. CAUB cases also had a lower GSH-Px (113.5 ± 44.7 vs. 163.9 ± 120.5, P = 0.0002), lower SOD levels (11.35 ± 5.6 vs. 13.75 ± 3.9, P = 0.008), and a higher LPO levels (15.5 ± 14.7 vs. 11.18 ± 11.2, P = 0.02) in the serum. Conclusions: A significantly higher concentration of As, Mn, and Pb was noted in the blood and urine of CAUB patients compared to controls. CAUB cases also had lower serum GSH-Px and SOD levels with a concomitant increased serum LPO assay suggesting underlying oxidative stress. [ABSTRACT FROM AUTHOR]

Summary: This paper presents the design of output feedback controllers for discrete‐time (DT) linear systems. New sufficient LMI conditions are derived for designing static H2$$ {H}_2 $$ and H∞$$ {H}_{\infty } $$ controllers using decomposition of an auxiliary matrix. The decomposition facilitates linearization of nonlinear term of reduced size to obtain linear matrix inequality criteria. This leads to less conservative results as shown in the numerical examples. In addition, the proposed static output feedback criteria is also used for designing dynamic output feedback controllers for DT systems. Furthermore, a comparative study is also made for the proposed design method with the results existing in the literature. Finally, a DT static output feedback H∞$$ {H}_{\infty } $$ controller is designed for a quarter‐car suspension system. Simulation results are provided to show the efficacy of the proposed design method. [ABSTRACT FROM AUTHOR]

A Hands-off control law is investigated to asymptotically stabilize a nonlinear system with input-quantization. The quantization parameters generated at the coder and decoder sides of the communication channel are mismatched and a time-varying ratio is modeled to show the non-synchronous adjustment of the quantization parameters. By the means of $[\mathcal {K,KL}]$ sector, the state-space is roughly divided into an attractive and non-attractive regions and a controller based on On-Off logic is utilized to remove the model uncertainties caused by the mismatch of the quantization parameters with limited control effort. Finally, the illustration of the proposed scheme is verified for an electronic circuit. [ABSTRACT FROM AUTHOR]

This paper proposes a distributed artificially delayed output feedback‐based leader–follower and leaderless consensus control for the uncertain general linear multiagent systems (MASs) with an arbitrary relative degree. Based on the measured relative output and their delayed information with respect to neighbours, two distributed controllers are designed, which relaxes the requirement of all relative states information of agents. Through the Lyapunov–Krasovskii functional, linear matrix inequalities (LMIs) are formulated, and these LMIs are feasible for arbitrary small delays selected by the user. Delay‐dependent sufficient conditions are provided to guarantee the asymptotic convergence of nominal error systems and ultimately uniform boundedness in the case of a perturbed error system, using the input to state stability (ISS) theory. Finally, the efficacy of the proposed method is illustrated through numerical examples. [ABSTRACT FROM AUTHOR]