高張力鋼板の大ひずみ異方硬化挙動の決定

内容の要約広島大学(Hiroshima University)博士(工学)Doctor of Engineeringdoctora

A Tracking Control of a Flexible-Robot Including the Dynamics of the Induction Motor as Actuator

Common assumption in analysis of a flexible one-link robot is to take account of a DC motor as actuator. This work presents the design and stability analysis of a tracking controller of a flexible-robot including the dynamics of a 3-phase induction motor, despite of its high nonlinear dynamics, to drive the joint of the one-link arm. In this manner, the dynamic model of a joint-flexible-robot is combined with the induction motor model to build the motion equations. A control law is proposed for the flexible one-arm robot to track a desired trajectory, thus, this control input is used like the reference torque for the induction motor control. A stability analysis by Lyapunov criterion is detailed to demonstrate the tracking errors are globally exponentially stable. Simulations show the effectiveness of the proposed approach even when the one-link arm is subjected to uncertainty in parameters and external disturbances

Evolution over Time of Ventilatory Management and Outcome of Patients with Neurologic Disease∗

OBJECTIVES: To describe the changes in ventilator management over time in patients with neurologic disease at ICU admission and to estimate factors associated with 28-day hospital mortality. DESIGN: Secondary analysis of three prospective, observational, multicenter studies. SETTING: Cohort studies conducted in 2004, 2010, and 2016. PATIENTS: Adult patients who received mechanical ventilation for more than 12 hours. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 20,929 patients enrolled, we included 4,152 (20%) mechanically ventilated patients due to different neurologic diseases. Hemorrhagic stroke and brain trauma were the most common pathologies associated with the need for mechanical ventilation. Although volume-cycled ventilation remained the preferred ventilation mode, there was a significant (p < 0.001) increment in the use of pressure support ventilation. The proportion of patients receiving a protective lung ventilation strategy was increased over time: 47% in 2004, 63% in 2010, and 65% in 2016 (p < 0.001), as well as the duration of protective ventilation strategies: 406 days per 1,000 mechanical ventilation days in 2004, 523 days per 1,000 mechanical ventilation days in 2010, and 585 days per 1,000 mechanical ventilation days in 2016 (p < 0.001). There were no differences in the length of stay in the ICU, mortality in the ICU, and mortality in hospital from 2004 to 2016. Independent risk factors for 28-day mortality were age greater than 75 years, Simplified Acute Physiology Score II greater than 50, the occurrence of organ dysfunction within first 48 hours after brain injury, and specific neurologic diseases such as hemorrhagic stroke, ischemic stroke, and brain trauma. CONCLUSIONS: More lung-protective ventilatory strategies have been implemented over years in neurologic patients with no effect on pulmonary complications or on survival. We found several prognostic factors on mortality such as advanced age, the severity of the disease, organ dysfunctions, and the etiology of neurologic disease