Funnel control for a moving water tank

We study tracking control for a moving water tank system, which is modelled using the Saint-Venant equations. The output is given by the position of the tank and the control input is the force acting on it. For a given reference signal, the objective is to achieve that the tracking error evolves within a prespecified performance funnel. Exploiting recent results in funnel control we show that it suffices to show that the operator associated with the internal dynamics of the system is causal, locally Lipschitz continuous and maps bounded functions to bounded functions. To show these properties we consider the linearized Saint-Venant equations in an abstract framework and show that it corresponds to a regular well-posed linear system, where the inverse Laplace transform of the transfer function defines a measure with bounded total variation.Comment: 11 page

Effect of respiratory muscle training in asthma: a systematic review and meta-analysis

Review[Abstract] Background: The last systematic review about respiratory muscle training (RMT) in people with asthma was published almost 10 years ago. Since then, several works have been published. Objective: To review the effect of RMT in people with asthma. Methods: We conducted a systematic review of research included up to September 2021 in PubMed/MEDLINE, PEDro, Scopus, Web of Science, CINAHL, LILACS, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov. We included randomized controlled trials and quasi-experimental studies assessing the effect of RMT on respiratory muscle function, rescue medication, asthma-related symptoms, lung function, exercise capacity, healthcare use, health-related quality of life (HRQoL) and adverse effects in people with asthma. Risk of bias and methodological quality were assessed with the Cochrane Risk of Bias assessment tool and the PEDro scale. Meta-analysis was performed whenever possible; otherwise a qualitative approach was followed. Results: Eleven studies (270 participants) were included, 10 with only adults and were included in the meta-analysis. Inspiratory muscle training (IMT) had beneficial effects on maximal inspiratory pressure (PImax: mean difference [MD] 21.95 cmH2O [95% confidence interval [CI] 15.05; 28.85]), with no changes in maximal expiratory pressure (MD 14.97 cmH2O [95%CI -5.65; 35.59]), lung function (forced expiratory volume in 1 sec: MD 0.06 [95%CI -0.14; 0.26] L; force vital capacity: MD 0.39 [95%CI -0.24; 1.02] L) and exercise capacity (standard mean difference [SMD] 1.73 [95%CI -0.61; 4.08]). Subgroup analysis revealed that IMT load >50% PImax and duration >6 weeks were beneficial for exercise capacity. The qualitative analysis suggested that IMT may have benefits on respiratory muscle endurance, rescue medication and exertional dyspnoea, with no adverse effects. Conclusions: This systematic review and meta-analysis showed a significant increase in PImax after IMT in adults with asthma and reinforced the relevance of the dose-response principle of training. More evidence is needed to clarify the effect of IMT in respiratory muscle endurance, rescue medication, exercise capacity, healthcare use and HRQoL

Treinamento físico e insuficiência cardíaca : biomarcadores e variáveis funcionais

Objetivo: Avaliar os efeitos do treinamento físico sobre biomarcadores e variáveis funcionais em pacientes com insuficiência cardíaca (IC). Métodos: A revisão sistemática e meta-análise incluiu ensaios clínicos randomizados (ECR) de indivíduos com IC que realizaram treinamento físico com os desfechos primários peptídeo natriurético B e fragmento N-terminal do peptídeo natriurético B. No ensaio clínico randomizado indivíduos com IC realizaram treinamento funcional ou de força, 3 vezes/semana, 12 semanas. Resultados: A revisão sistemática demonstrou associação entre o treinamento físico e peptídeos natriuréticos. O ECR demonstrou que treinamento funcional e de força melhoram o VO2 de pico e a qualidade de vida. Conclusões: O treinamento físico em pacientes com IC está associado a efeitos benéficos sobre os peptídeos natriuréticos e biomarcadores inflamatórios, uma vez que todos foram reduzidos pela intervenção. O treinamento funcional e de força são igualmente seguros e eficazes para melhorar a capacidade funcional, qualidade de vida e funcionalidade de indivíduos com IC.Objective: To evaluate the effects of physical training on biomarkers and functional variables in patients with heart failure (HF). Methods: The systematic review and meta-analysis included randomized clinical trials (RCT) of individuals with HF who underwent physical training with the primary endpoints of natriuretic peptide B and N-terminal fragment of natriuretic peptide B. In the randomized clinical trial, subjects with HF underwent functional training or strength training, 3 times/week, 12 weeks. Results: The systematic review showed an association between physical training and natriuretic peptides. The RCT showed that functional and strength training improve peak VO2 and quality of life. Conclusions: Physical training in patients with HF is associated with beneficial effects on natriuretic peptides and inflammatory biomarkers, since all were reduced by the intervention. Functional and strength training are equally safe and effective for improving functional capacity, quality of life, and functionality for individuals with HF

Asymptotic tracking by funnel control with internal models

Funnel control achieves output tracking with guaranteed tracking performance for unknown systems and arbitrary reference signals. In particular, the tracking error is guaranteed to satisfy time-varying error bounds for all times (it evolves in the funnel). However, convergence to zero cannot be guaranteed, but the error often stays close to the funnel boundary, inducing a comparatively large feedback gain. This has several disadvantages (e.g. poor tracking performance and sensitivity to noise due to the underlying high-gain feedback principle). In this paper, therefore, the usually known reference signal is taken into account during funnel controller design, i.e. we propose to combine the well-known internal model principle with funnel control. We focus on linear systems with linear reference internal models and show that under mild adjustments of funnel control, we can achieve asymptotic tracking for a whole class of linear systems (i.e. without relying on the knowledge of system parameters)