目的:观察Centurion超声乳化仪主控液流系统应用于白内障手术的有效性和安全性。方法:前瞻性研究。于2018-10/12选取年龄相关性白内障(Emery核硬度分级Ⅱ~Ⅳ级)患者133例133眼,随机分为两组,试验组采用主控液流系统,对照组采用重力液流...目的:观察Centurion超声乳化仪主控液流系统应用于白内障手术的有效性和安全性。方法:前瞻性研究。于2018-10/12选取年龄相关性白内障(Emery核硬度分级Ⅱ~Ⅳ级)患者133例133眼,随机分为两组,试验组采用主控液流系统,对照组采用重力液流系统。术中记录累积释放能量(CDE)、抽吸时间(AT)、灌注液用量(EFU),分别于术前和术后1d测量角膜内皮细胞计数(ECD)和中央角膜厚度(CCT)。结果:术中试验组患者的CDE、AT、EFU明显低于对照组(均P<0.05),术后1d试验组和对照组患者ECD均较术前轻度减少,CCT均较术前轻度增加,但两组间均无差异(2056.06±308.10cells/mm^2 vs 1997.26±297.55cells/mm^2,532.75±12.02μm vs 531.02±13.00μm;均P>0.05),且两组患者术中及术后均未发生严重的眼部并发症。结论:Centurion主控液流系统在整个手术过程中能够维持恒定的眼内压,有效提高了前房稳定性,比传统重力液流系统更加安全高效。展开更多
A semi-active force tracking PI controller is formulated and analyzed for a magnetorheological (MR) fluid-based damper in conjunction with a quarter-vehicle model. Two different models of the MR-damper are integrated ...A semi-active force tracking PI controller is formulated and analyzed for a magnetorheological (MR) fluid-based damper in conjunction with a quarter-vehicle model. Two different models of the MR-damper are integrated into the closed-loop system model, which includes: a model based upon the mean force-velocity (f-v) behaviour; and a model synthesis comprising inherent nonsmooth hysteretic force and the force limiting properties of the MR damper. The vehicle models are analyzed to study the vibration attenuation performance of the MR-damper using the semi-active force tracking PI control algorithm. The simulation results are also presented to demonstrate the influence of the damper nonlinearity, specifically the hysteresis, on the suspension performance. The results show that the proposed control strategy can yield superior vibration attenuation performance of the vehicle suspension actuated by the controllable MR-damper not only in the sprung mass resonance and the ride zones, but also in the vicinity of the wheel-hop. The results further show that the presence of damper hystersis deteriorates the suspension performance.展开更多
文摘目的:观察Centurion超声乳化仪主控液流系统应用于白内障手术的有效性和安全性。方法:前瞻性研究。于2018-10/12选取年龄相关性白内障(Emery核硬度分级Ⅱ~Ⅳ级)患者133例133眼,随机分为两组,试验组采用主控液流系统,对照组采用重力液流系统。术中记录累积释放能量(CDE)、抽吸时间(AT)、灌注液用量(EFU),分别于术前和术后1d测量角膜内皮细胞计数(ECD)和中央角膜厚度(CCT)。结果:术中试验组患者的CDE、AT、EFU明显低于对照组(均P<0.05),术后1d试验组和对照组患者ECD均较术前轻度减少,CCT均较术前轻度增加,但两组间均无差异(2056.06±308.10cells/mm^2 vs 1997.26±297.55cells/mm^2,532.75±12.02μm vs 531.02±13.00μm;均P>0.05),且两组患者术中及术后均未发生严重的眼部并发症。结论:Centurion主控液流系统在整个手术过程中能够维持恒定的眼内压,有效提高了前房稳定性,比传统重力液流系统更加安全高效。
文摘A semi-active force tracking PI controller is formulated and analyzed for a magnetorheological (MR) fluid-based damper in conjunction with a quarter-vehicle model. Two different models of the MR-damper are integrated into the closed-loop system model, which includes: a model based upon the mean force-velocity (f-v) behaviour; and a model synthesis comprising inherent nonsmooth hysteretic force and the force limiting properties of the MR damper. The vehicle models are analyzed to study the vibration attenuation performance of the MR-damper using the semi-active force tracking PI control algorithm. The simulation results are also presented to demonstrate the influence of the damper nonlinearity, specifically the hysteresis, on the suspension performance. The results show that the proposed control strategy can yield superior vibration attenuation performance of the vehicle suspension actuated by the controllable MR-damper not only in the sprung mass resonance and the ride zones, but also in the vicinity of the wheel-hop. The results further show that the presence of damper hystersis deteriorates the suspension performance.
