In this paper, the three-dimensional (3D) coupling effect is discussed for nanowire junctionless silicon-on-insulator (SOI) FinFETs. With fin width decreasing from 100 nm to 7 nm, the electric field induced by the...In this paper, the three-dimensional (3D) coupling effect is discussed for nanowire junctionless silicon-on-insulator (SOI) FinFETs. With fin width decreasing from 100 nm to 7 nm, the electric field induced by the lateral gates increases and therefore the influence of back gate on the threshold voltage weakens. For a narrow and tall fin, the lateral gates mainly control the channel and therefore the effect of back gate decreases. A simple two-dimensional (2D) potential model is proposed for the subthreshold region of junctionless SO1 FinFET. TCAD simulations validate our model. It can be used to extract the threshold voltage and doping concentration. In addition, the tuning of back gate on the threshold voltage can be predicted.展开更多
为提高自动驾驶车辆的路径跟踪精度,针对自动驾驶车辆横纵向耦合控制问题,提出了带有前馈控制的PID+LQR联合控制策略。首先,利用二自由度车辆动力学模型构建路径跟踪误差状态方程,制定横纵向控制流程。随后,设计了用于横向控制的线性二...为提高自动驾驶车辆的路径跟踪精度,针对自动驾驶车辆横纵向耦合控制问题,提出了带有前馈控制的PID+LQR联合控制策略。首先,利用二自由度车辆动力学模型构建路径跟踪误差状态方程,制定横纵向控制流程。随后,设计了用于横向控制的线性二次型调节(linear quadratic regulator,LQR)控制策略和用于纵向控制的比例积分微分(proportional integral differential,PID)控制策略,将横纵向控制器进行整合,使得车辆在接收到决策规划系统给出的期望指令后可以进行跟踪行驶。借助CarSim和MATLAB/Simulink联合仿真平台,在连续工况下对该控制策略进行测试。结果表明,提出的横纵向耦合控制策略可控制车辆沿着规划的轨迹行驶,且可将跟踪误差控制在理想的范围内。展开更多
Buckling initiation devices/techniques,including sleepers,distributed buoyancy,snake lay,and residual curvature method(RCM),have recently been widely applied in engineering.These initiated buckles may induce a long pi...Buckling initiation devices/techniques,including sleepers,distributed buoyancy,snake lay,and residual curvature method(RCM),have recently been widely applied in engineering.These initiated buckles may induce a long pipeline to transform into multiple short pipeline segments,which promote the occurrence of pipeline walking.Thus,a pipeline,which is designed to buckle laterally,may laterally and axially displace over time when subjected to repeated heating and cooling cycles.This study aims to reveal the coupling mechanism of pipeline walking and global lateral buckling.First,an analytic solution is proposed to estimate the walking of pipeline segments between two adjacent buckles.Then,the sensitivity of this method to heating and cooling cycles is analyzed.Results show the applicability of the proposed walking analytical solution of buckling pipelines.Subsequently,an influence analysis of walking on global buckling,including the capacity of buckling initiation,buckling amplitude,buckling mode,and failure assessment of the buckling pipeline,is performed.The results reveal that the effect of walking on the buckling axial force is negligible.However,pipeline walking will aggravate the asymmetry of the pipeline buckling and the failure parameters of the pipeline during the post-buckling.展开更多
基金supported by the Research Program of the National University of Defense Technology(Grant No.JC 13-06-04)
文摘In this paper, the three-dimensional (3D) coupling effect is discussed for nanowire junctionless silicon-on-insulator (SOI) FinFETs. With fin width decreasing from 100 nm to 7 nm, the electric field induced by the lateral gates increases and therefore the influence of back gate on the threshold voltage weakens. For a narrow and tall fin, the lateral gates mainly control the channel and therefore the effect of back gate decreases. A simple two-dimensional (2D) potential model is proposed for the subthreshold region of junctionless SO1 FinFET. TCAD simulations validate our model. It can be used to extract the threshold voltage and doping concentration. In addition, the tuning of back gate on the threshold voltage can be predicted.
文摘为提高自动驾驶车辆的路径跟踪精度,针对自动驾驶车辆横纵向耦合控制问题,提出了带有前馈控制的PID+LQR联合控制策略。首先,利用二自由度车辆动力学模型构建路径跟踪误差状态方程,制定横纵向控制流程。随后,设计了用于横向控制的线性二次型调节(linear quadratic regulator,LQR)控制策略和用于纵向控制的比例积分微分(proportional integral differential,PID)控制策略,将横纵向控制器进行整合,使得车辆在接收到决策规划系统给出的期望指令后可以进行跟踪行驶。借助CarSim和MATLAB/Simulink联合仿真平台,在连续工况下对该控制策略进行测试。结果表明,提出的横纵向耦合控制策略可控制车辆沿着规划的轨迹行驶,且可将跟踪误差控制在理想的范围内。
基金supported by the China National Postdoctoral Program for Innovative Talents(No.BX2021213)the Natural Science Foundation for Distinguished Young Scholars of China(No.51825904).
文摘Buckling initiation devices/techniques,including sleepers,distributed buoyancy,snake lay,and residual curvature method(RCM),have recently been widely applied in engineering.These initiated buckles may induce a long pipeline to transform into multiple short pipeline segments,which promote the occurrence of pipeline walking.Thus,a pipeline,which is designed to buckle laterally,may laterally and axially displace over time when subjected to repeated heating and cooling cycles.This study aims to reveal the coupling mechanism of pipeline walking and global lateral buckling.First,an analytic solution is proposed to estimate the walking of pipeline segments between two adjacent buckles.Then,the sensitivity of this method to heating and cooling cycles is analyzed.Results show the applicability of the proposed walking analytical solution of buckling pipelines.Subsequently,an influence analysis of walking on global buckling,including the capacity of buckling initiation,buckling amplitude,buckling mode,and failure assessment of the buckling pipeline,is performed.The results reveal that the effect of walking on the buckling axial force is negligible.However,pipeline walking will aggravate the asymmetry of the pipeline buckling and the failure parameters of the pipeline during the post-buckling.