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This paper introduces an innovative adaptive nonsingular Second-Order Terminal Sliding Mode (SOTSM) control strategy specifically designed to stabilise disturbed nonlinear Cyber-Physical Systems (CPSs) within a finite timeframe. Unlike the conventional methods, our approach incorporates a novel nonlinear sliding surface that eliminates the need for a reaching step, significantly enhancing the system's robustness. Novel real-time adaptive control laws are developed to cope with external perturbations, time-varying delays, and cyber-attack on actuators without requiring the identification of their upper bounds. The proposed method ensures robust performance for time-varying delayed and disturbed nonlinear CPSs, even in the face of strong cyber-attacks targeting the actuators. Moreover, the proposed method has distinct advantages: it delivers rapid response times, enhanced flexibility, exceptional accuracy, smooth and robust control devoid of transient fluctuations or chattering, and ensures finite-time convergence. Simulation results comprehensively demonstrate the superior efficiency and success of our proposed technique compared to traditional methods such as integral Sliding Mode Control (SMC) and State-Feedback Control (SFC) schemes. [ABSTRACT FROM AUTHOR]

Summary: In this study, a novel strategy of the adaptive non‐singular second‐order terminal sliding mode (SOTSM) control technique for the finite time stabilization of cyber‐physical systems (CPSs) is proposed. By utilizing the proposed nonlinear sliding surface, the reaching phase is obliterated and the entire system's robust operation is ameliorated. The offered online adaptive laws deal with the unwanted disturbances and cyber‐attacks, so that there is no need to identify their upper bounds. The designed adaptive non‐singular SOTSM control technique provides the strong robustness of CPSs in the presence of the unwanted disturbances and cyber‐attacks. Also, it guarantees high precision, pliable performance, fast response, smooth control, chattering‐free operation without transient oscillations, and appropriate convergence in the finite time. Numerical simulation results demonstrate effectiveness and success of the proposed adaptive non‐singular SOTSM control technique compared to the results of state feedback control (SFC), conventional sliding mode control (SMC), and integral‐type SMC methods. [ABSTRACT FROM AUTHOR]

Summary: This article studies a novel technique of the adaptive terminal sliding mode (TSM) control for the finite time stabilization of cyber‐physical systems (CPSs). By using the proposed nonlinear sliding surface, the reaching mode is eliminated and the entire system robust procedure is ameliorated. The used adaptive laws are dealt with the cyber‐attacks and external disturbances which their upper bounds are not needed to be recognized, where suggested approach is more pliable in the real performance. The presented new adaptive TSM control technique guarantees the system robustness versus cyber‐attacks and external disturbances. Furthermore, the proposed control method obliterated the chattering behavior utilizing the hyperbolic tangent function and the continuous adaptive parameters in the control law. Numerical simulation results indicate the proposed adaptive TSM control technique's effectiveness and success compared to the results of state feedback control, conventional sliding mode control (SMC), traditional integral‐type SMC, and adaptive integral‐type SMC methods. [ABSTRACT FROM AUTHOR]

Purpose: Patients with chronic obstructive pulmonary disease (COPD) suffer from many health problems including poor sleep. This paper aims to evaluate the relationship between diet quality indices (DQIs) and sleep quality in COPD. Design/methodology/approach: The current cross-sectional study was carried on 121 COPD patients. Subjective quality of sleep was determined by Pittsburgh Sleep Quality Index (PSQI) and categorized into "poor" and "good" sleep quality. Dietary history was assessed by the DQIs. Disease status was categorized according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) Guidelines. Findings: In total, 103 men and 18 women with a mean age of 66.1 ±10.9 were studied. The subjects were categorized into four groups based on GOLD; 3.3% of subjects were at Stage 1, 38% in Stage 2, 38% in Stage 3 and 20.7% in Stage 4. In total, 38% of subjects were good, and 62% were bad sleepers according to PSQI score. There was no significant relationship between the severity of COPD and PSQI score. We observed a significant inverse relation between PSQI total score and Mediterranean diet (MED) scale, Healthy Eating Index (HEI)-2010 and HEI-2005 (p = 0.024, 0.037 and 0.024, respectively) in males. Originality/value: This study showed a high prevalence of poor quality of sleep and sleep disturbances among COPD patients. There was an inverse association between PSQI and sleep disorders and DQIs scores in COPD patients. Regardless of the severity of airflow obstruction, poor diet quality may constitute a risk factor for sleep quality. [ABSTRACT FROM AUTHOR]

Challenges in the assessment, diagnosis and management of severe, difficult-to-control asthma are increasingly regarded as clinical needs yet unmet. The assessments required to determine asthma severity, comorbidities and confounding factors, disease phenotypes and optimal treatment are among the controversial issues in the field. The respiratory care experts' input forum (RC-EIF), comprised of an Iranian panel of experts, reviewed the definition, appraised the available guidelines and provided a consensus for evaluation and treatment of severe asthma in adults. A systematic literature review followed by discussions during and after the forum, yielded the present consensus. The expert panel used the appraisal of guidelines for research and evaluation-II (AGREE-II) protocol to define an initial locally-adapted strategy for the management of severe asthma. Severe asthma is considered a heterogeneous condition with various phenotypes. Issues such as assessment of difficult-to-control asthma, phenotyping, the use of blood and sputum eosinophil count, exhaled nitric oxide to guide therapy, the position of anti-IgE antibody, methotrexate, macrolide antibiotics, antifungal agents and bronchial thermoplasty as well as the use of established, recently-developed and evolving treatment approaches were discussed and unanimously agreed upon in the panel. A systematic approach is required to ensure proper diagnosis, evaluate compliance, and to identify comorbidities and triggering factors in severe asthma. Phenotyping helps select optimized treatment. The treatment approach laid down by the Global Initiative for Asthma (GINA) needs to be followed, while the benefit of using biological therapies should be weighed against the cost and safety concerns. [ABSTRACT FROM AUTHOR]