In this paper,an optimal guidance law for missiles with impact angle and miss distance constraints is proposed to achieve the maximal terminal velocity. The normal acceleration command that includes the timevarying co...In this paper,an optimal guidance law for missiles with impact angle and miss distance constraints is proposed to achieve the maximal terminal velocity. The normal acceleration command that includes the timevarying coefficients is introduced to satisfy the desired impact angle as well as zero miss distance according to the geometric relation and relative motion parameters between missile and target. The problem is formulated as an optimal control problem by defining the angle of velocity error and flight-path angle as state variables and maximizing a performance index of the terminal velocity. The analytical form of the proposed guidance law is obtained as the solution of the optimal control problem combining optimal control theory and numerical value computation method. Nonlinear simulations of various situations demonstrate the performance and feasibility of the proposed optimal guidance law.展开更多
A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including H-1-H-1...A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including H-1-H-1 COSY, H-1-C-13 HETCOR, COLOC and NOESY techniques.展开更多
This paper presents a new particle swarm optimization( PSO) algorithm to optimize the trajectory of morphing-wing missile so as to achieve the enlargement of the maximum range. Equations of motion for the twodimension...This paper presents a new particle swarm optimization( PSO) algorithm to optimize the trajectory of morphing-wing missile so as to achieve the enlargement of the maximum range. Equations of motion for the twodimensional dynamics are derived by treating the missile as an ideal controllable mass point. An investigation of aerodynamic characteristics of morphing-wing missile with varying geometries is performed. After deducing the optimizing trajectory model for maximizing range,a type of discrete method is put forward for taking optimization control problem into nonlinear dynamic programming problem. The optimal trajectory is solved by using PSO algorithm and penalty function method. The simulation results suggest that morphing-wing missile has the larger range than the fixed-shape missile when launched at supersonic speed,while morphing-wing missile has no obvious range increment than the fixed-shape missile at subsonic speed.展开更多
基金Sponsored by the National Security Academic Foundation(Grant No.11176012)the CALT University Joint innovation Foundation(Grant No.CALT 201302)
文摘In this paper,an optimal guidance law for missiles with impact angle and miss distance constraints is proposed to achieve the maximal terminal velocity. The normal acceleration command that includes the timevarying coefficients is introduced to satisfy the desired impact angle as well as zero miss distance according to the geometric relation and relative motion parameters between missile and target. The problem is formulated as an optimal control problem by defining the angle of velocity error and flight-path angle as state variables and maximizing a performance index of the terminal velocity. The analytical form of the proposed guidance law is obtained as the solution of the optimal control problem combining optimal control theory and numerical value computation method. Nonlinear simulations of various situations demonstrate the performance and feasibility of the proposed optimal guidance law.
文摘A new styryl-lactone compound, named as leiocarpin A (1), was isolated from Goniothalamus leiocarpus. Its structure and relative configuration were determined by means of spectrum particularly 2D NMR including H-1-H-1 COSY, H-1-C-13 HETCOR, COLOC and NOESY techniques.
基金Sponsored by the Natural Science Association Foundation(NSAF)of China(Grant No.11176012)the Research Innovation Project for Graduate Student of Jiangsu-Provincial Ordinary University(Grant No.KLYX15-0394)
文摘This paper presents a new particle swarm optimization( PSO) algorithm to optimize the trajectory of morphing-wing missile so as to achieve the enlargement of the maximum range. Equations of motion for the twodimensional dynamics are derived by treating the missile as an ideal controllable mass point. An investigation of aerodynamic characteristics of morphing-wing missile with varying geometries is performed. After deducing the optimizing trajectory model for maximizing range,a type of discrete method is put forward for taking optimization control problem into nonlinear dynamic programming problem. The optimal trajectory is solved by using PSO algorithm and penalty function method. The simulation results suggest that morphing-wing missile has the larger range than the fixed-shape missile when launched at supersonic speed,while morphing-wing missile has no obvious range increment than the fixed-shape missile at subsonic speed.