This study provides potential climate projections for Central Asia(CA)based on multi-regional climate model(RCM)outputs from the Coordinated Regional Climate Downscaling Experiment for Central Asia(CORDEX-CAII).Despit...This study provides potential climate projections for Central Asia(CA)based on multi-regional climate model(RCM)outputs from the Coordinated Regional Climate Downscaling Experiment for Central Asia(CORDEX-CAII).Despite some systematic biases,all RCMs effectively capture the main features of observed temperature and precipitation means and extremes over CA,with notable variations in model performance due to differences in the driving global climate models and the RCMs themselves.Overall,REMO consistently outperforms ALARO in simulating temperature-related indices,and ALARO-0 provides more accurate simulations for precipitation-related indices,and the multimodel ensemble(MME)tends to outperform individual RCMs.Under the representative concentration pathway(RCP)scenarios of RCP2.6 and RCP8.5,the MME results indicate a clear warming trend across CA for all temperature-related indices,except for the diurnal temperature range,with annual temperatures projected to increase by 0.15℃/10 yr and 0.53℃/10 yr,respectively.Both scenarios exhibit similar spatial distributions in projected annual precipitation,characterized by peak increases of~0.2 mm per day in northern CA.The number of consecutive dry days is projected to slightly increase under RCP8.5,while it is expected to slightly decrease under RCP2.6.This study improves our understanding of the applicability of RCMs in CA and provides reliable projections of future climate change.展开更多
本文开展以可靠性为中心的维修(Reliability Centered Maintenance,RCM)理论在航空部件质量安全中的应用研究。主要阐述RCM理论的核心概念与行业定义;以某航空公司B737NG飞机迎角(Angle of Attack,AOA)传感器故障事件为例,分析RCM理论...本文开展以可靠性为中心的维修(Reliability Centered Maintenance,RCM)理论在航空部件质量安全中的应用研究。主要阐述RCM理论的核心概念与行业定义;以某航空公司B737NG飞机迎角(Angle of Attack,AOA)传感器故障事件为例,分析RCM理论在故障诊断、维修决策和技术改进中的应用,通过梳理事件经过、排故流程和原因分析,揭示RCM理论对保障飞行安全的作用;提出优化实时监控、构建数据支撑体系、强化空地协同等建议,提升航空部件维修效率与安全性,支持航空维修体系智能化升级。展开更多
【目的】针对几何误差和非几何误差导致远程运动中心(Remote Center of Motion,RCM)机械臂运动过程中产生RCM约束点位置误差,进而存在一定的安全性问题,提出了一种微创手术机器人RCM机械臂广义运动学误差建模与补偿方法。【方法】首先,...【目的】针对几何误差和非几何误差导致远程运动中心(Remote Center of Motion,RCM)机械臂运动过程中产生RCM约束点位置误差,进而存在一定的安全性问题,提出了一种微创手术机器人RCM机械臂广义运动学误差建模与补偿方法。【方法】首先,基于切比雪夫多项式建立表征几何误差和非几何误差引起的关节相关运动学误差的误差模型;然后,通过最小二乘法对误差模型中的多项式系数和运动学参数误差进行辨识;最后,采用关节空间补偿的方法,以降低RCM约束点位置误差。【结果】试验结果表明,补偿后的RCM约束点位置误差由2.7261 mm减小到0.6415 mm,减小了约76.5%。展开更多
基金jointly supported by the Second Tibetan Plateau Scientific Expedition and Research Program[grant number 2019QZKK0103]the National Natural Science Foundation of China[grant number 42293294]the China Meteorological Administration Climate Change Special Program[grant number QBZ202303]。
文摘This study provides potential climate projections for Central Asia(CA)based on multi-regional climate model(RCM)outputs from the Coordinated Regional Climate Downscaling Experiment for Central Asia(CORDEX-CAII).Despite some systematic biases,all RCMs effectively capture the main features of observed temperature and precipitation means and extremes over CA,with notable variations in model performance due to differences in the driving global climate models and the RCMs themselves.Overall,REMO consistently outperforms ALARO in simulating temperature-related indices,and ALARO-0 provides more accurate simulations for precipitation-related indices,and the multimodel ensemble(MME)tends to outperform individual RCMs.Under the representative concentration pathway(RCP)scenarios of RCP2.6 and RCP8.5,the MME results indicate a clear warming trend across CA for all temperature-related indices,except for the diurnal temperature range,with annual temperatures projected to increase by 0.15℃/10 yr and 0.53℃/10 yr,respectively.Both scenarios exhibit similar spatial distributions in projected annual precipitation,characterized by peak increases of~0.2 mm per day in northern CA.The number of consecutive dry days is projected to slightly increase under RCP8.5,while it is expected to slightly decrease under RCP2.6.This study improves our understanding of the applicability of RCMs in CA and provides reliable projections of future climate change.
文摘本文开展以可靠性为中心的维修(Reliability Centered Maintenance,RCM)理论在航空部件质量安全中的应用研究。主要阐述RCM理论的核心概念与行业定义;以某航空公司B737NG飞机迎角(Angle of Attack,AOA)传感器故障事件为例,分析RCM理论在故障诊断、维修决策和技术改进中的应用,通过梳理事件经过、排故流程和原因分析,揭示RCM理论对保障飞行安全的作用;提出优化实时监控、构建数据支撑体系、强化空地协同等建议,提升航空部件维修效率与安全性,支持航空维修体系智能化升级。
文摘【目的】针对几何误差和非几何误差导致远程运动中心(Remote Center of Motion,RCM)机械臂运动过程中产生RCM约束点位置误差,进而存在一定的安全性问题,提出了一种微创手术机器人RCM机械臂广义运动学误差建模与补偿方法。【方法】首先,基于切比雪夫多项式建立表征几何误差和非几何误差引起的关节相关运动学误差的误差模型;然后,通过最小二乘法对误差模型中的多项式系数和运动学参数误差进行辨识;最后,采用关节空间补偿的方法,以降低RCM约束点位置误差。【结果】试验结果表明,补偿后的RCM约束点位置误差由2.7261 mm减小到0.6415 mm,减小了约76.5%。
