43 research outputs found
Analytical research of damping efficiency and heat generation of magnetorheological damper
International audienceMagnetorheological (MR) dampers are currently used in various areas, such as: human prosthetics,seismic protection, active suspensions, safety systems, amongst other. This paper deals with theproper design of a MR damper in the innovative field for vibration control. A methodology forcalculation some principal characteristics of the damper such as: electromagnet’s magnetic fieldvalue, emitted heat and damping force is presented. The methodology is based on analyticcalculations of the characteristics and finite element method analysis. The obtained theoreticalresults were confirmed by performed experimental tests, thanks to a specially designed and realisedMR damper. Two main geometrical characteristics of the damper, namely: piston thickness andelectromagnet width were optimally chosen, thus allowing to reach maximum damping force
Analytical research of damping efficiency and heat generation of magnetorheological damper
International audienceMagnetorheological (MR) dampers are currently used in various areas, such as: human prosthetics,seismic protection, active suspensions, safety systems, amongst other. This paper deals with theproper design of a MR damper in the innovative field for vibration control. A methodology forcalculation some principal characteristics of the damper such as: electromagnet’s magnetic fieldvalue, emitted heat and damping force is presented. The methodology is based on analyticcalculations of the characteristics and finite element method analysis. The obtained theoreticalresults were confirmed by performed experimental tests, thanks to a specially designed and realisedMR damper. Two main geometrical characteristics of the damper, namely: piston thickness andelectromagnet width were optimally chosen, thus allowing to reach maximum damping force
Analytical research of damping efficiency and heat generation of magnetorheological damper
Reduced Mortality Associated With the Use of ACE Inhibitors in Patients With Type 2 Diabetes
Association of Guideline-Recommended COPD Inhaler Regimens With Mortality, Respiratory Exacerbations, and Quality of Life A Secondary Analysis of the Long-Term Oxygen Treatment Trial
BackgroundAlthough inhaled therapy reduces exacerbations among patients with COPD, the effectiveness of providing inhaled treatment per risk stratification models remains unclear.Research questionAre inhaled regimens that align with the 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy associated with clinically important outcomes?Study design and methodsWe conducted secondary analyses of Long-term Oxygen Treatment Trial (LOTT) data. The trial enrolled patients with COPD with moderate resting or exertional hypoxemia between 2009 and 2015. Our exposure was the patient-reported inhaled regimen at enrollment, categorized as either aligning with, undertreating, or potentially overtreating per the 2017 GOLD strategy. Our primary composite outcome was time to death or first hospitalization for COPD. Additional outcomes included individual components of the composite outcome and time to first exacerbation. We generated multivariable Cox proportional hazard models across strata of GOLD-predicted exacerbation risk (high vs low) to estimate between-group hazard ratios for time to event outcomes. We adjusted models a priori for potential confounders, clustered by site.ResultsThe trial enrolled 738 patients (73.4% men; mean age, 68.8 years). Of the patients, 571 (77.4%) were low risk for future exacerbations. Of the patients, 233 (31.6%) reported regimens aligning with GOLD recommendations; most regimens (54.1%) potentially overtreated. During a 2.3-year median follow-up, 332 patients (44.9%) experienced the composite outcome. We found no difference in time to composite outcome or death among patients reporting regimens aligning with recommendations compared with undertreated patients. Among patients at low risk, potential overtreatment was associated with higher exacerbation risk (hazard ratio, 1.42; 95% CI, 1.09-1.87), whereas inhaled corticosteroid treatment was associated with 64% higher risk of pneumonia (incidence rate ratio, 1.64; 95% CI, 1.01-2.66).InterpretationAmong patients with COPD with moderate hypoxemia, we found no difference in clinical outcomes between inhaled regimens aligning with the 2017 GOLD strategy compared with those that were undertreated. These findings suggest the need to reevaluate the effectiveness of risk stratification model-based inhaled treatment strategies