A trajectory shaping guidance law based on virtua angle （TSGLBVA） is proposed for a re-entry vehicle with the constraints of terminal impact angles and their time derivatives. In the view of differential properties ...A trajectory shaping guidance law based on virtua angle （TSGLBVA） is proposed for a re-entry vehicle with the constraints of terminal impact angles and their time derivatives. In the view of differential properties of the maneuvering trajectory, a virtual angle and a virtual radius are defined. Also, the shaping trajectory of the vehicle is established by the polynomials of the virtual angle. Then, four optimized parameters are selected according to the theorem of parameters transformation presented in this paper. Finally, a convergent variant of the Nelder-Mead algorithm is adopted to obtain the reference trajectory, and a trajectory feedback tracking guidance law is designed. The simulation results demonstrate that the TSGLBVA ensures the re-entry vehicle to impact a target precisely from a specified direction with smal terminal load factor command, as well as to obtain a maximum or constrained terminal velocity according to various requirements.展开更多
为有效应对气候变化,促进虚拟电厂(virtual power plant,VPP)的健康发展,基于区域气候模型(providing regional climate for impact studies,PRECIS)、BP神经网络预测模型和区间优化算法,提出了适应气候变化的VPP运行优化模型。应用PRE...为有效应对气候变化,促进虚拟电厂(virtual power plant,VPP)的健康发展,基于区域气候模型(providing regional climate for impact studies,PRECIS)、BP神经网络预测模型和区间优化算法,提出了适应气候变化的VPP运行优化模型。应用PRECIS模拟2025年不同碳排放情景下气温、风速和辐射量等气象要素的变化规律;基于PRECIS气象要素模拟结果,应用BP神经网络模型预测2025年光伏电站的发电量;将区间优化算法与发电量预测结果相耦合,以此降低光伏发电不确定性对优化模型模拟结果的影响。结果显示,该模型可生成适应气候变化的VPP最优运行策略,降低系统运行成本,提升VPP运行效益。展开更多
文摘A trajectory shaping guidance law based on virtua angle （TSGLBVA） is proposed for a re-entry vehicle with the constraints of terminal impact angles and their time derivatives. In the view of differential properties of the maneuvering trajectory, a virtual angle and a virtual radius are defined. Also, the shaping trajectory of the vehicle is established by the polynomials of the virtual angle. Then, four optimized parameters are selected according to the theorem of parameters transformation presented in this paper. Finally, a convergent variant of the Nelder-Mead algorithm is adopted to obtain the reference trajectory, and a trajectory feedback tracking guidance law is designed. The simulation results demonstrate that the TSGLBVA ensures the re-entry vehicle to impact a target precisely from a specified direction with smal terminal load factor command, as well as to obtain a maximum or constrained terminal velocity according to various requirements.
文摘为有效应对气候变化,促进虚拟电厂(virtual power plant,VPP)的健康发展,基于区域气候模型(providing regional climate for impact studies,PRECIS)、BP神经网络预测模型和区间优化算法,提出了适应气候变化的VPP运行优化模型。应用PRECIS模拟2025年不同碳排放情景下气温、风速和辐射量等气象要素的变化规律;基于PRECIS气象要素模拟结果,应用BP神经网络模型预测2025年光伏电站的发电量;将区间优化算法与发电量预测结果相耦合,以此降低光伏发电不确定性对优化模型模拟结果的影响。结果显示,该模型可生成适应气候变化的VPP最优运行策略,降低系统运行成本,提升VPP运行效益。
