多弹协同是导弹武器的热点研究方向,具有很高的研究价值,而如何规划多个导弹的飞行弹道,则是其中的重要研究内容。以助推滑翔导弹滑翔段弹道为研究对象,以规划多条优质弹道轨迹为目的,提出了一种基于MOEA/D(multi-objective evolutionar...多弹协同是导弹武器的热点研究方向,具有很高的研究价值,而如何规划多个导弹的飞行弹道,则是其中的重要研究内容。以助推滑翔导弹滑翔段弹道为研究对象,以规划多条优质弹道轨迹为目的,提出了一种基于MOEA/D(multi-objective evolutionary algorithm based on decomposition)算法的多弹道轨迹仿真实现方法。选取射程最大和末速最大作为目标函数,进行滑翔段弹道规划,同时,为降低初始种群对多目标优化问题的影响,借助伪谱法为多目标优化算法提供高质量初始种群。经仿真验证,该方法可得到多条具备射程最优和末速最优的导弹飞行弹道。展开更多
A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were invest...A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were investigated. According to the phase composition analyzed by X-ray powder diffraction, there is no crystalline phase except Ba2Ca(BO3)2 in the sample. Ba2Ca(BO3)2:Dy3+ can produce white emission under 348 nm excitation. The emission intensities of Ba2Ca(BO3)2:Dy3+ are affected by Dy3+ concentration. The concentration quenching effect was analyzed, and the concentration quenching mechanism was verified as dipole-dipole interaction. The critical distance(R c) obtained based on the crystal structure data is 2.911 nm. At 150℃, the emission intensity of Ba2Ca(BO3)2:Dy3+ is 68.0% of the initial value at room temperature. The activation energy for the thermal quenching calculated is 0.202 e V. Moreover, the CIE chromaticity coordinates of Ba2Ca(BO3)2:Dy3+ locate in the white region of(0.319, 0.356).展开更多
文摘多弹协同是导弹武器的热点研究方向,具有很高的研究价值,而如何规划多个导弹的飞行弹道,则是其中的重要研究内容。以助推滑翔导弹滑翔段弹道为研究对象,以规划多条优质弹道轨迹为目的,提出了一种基于MOEA/D(multi-objective evolutionary algorithm based on decomposition)算法的多弹道轨迹仿真实现方法。选取射程最大和末速最大作为目标函数,进行滑翔段弹道规划,同时,为降低初始种群对多目标优化问题的影响,借助伪谱法为多目标优化算法提供高质量初始种群。经仿真验证,该方法可得到多条具备射程最优和末速最优的导弹飞行弹道。
文摘A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were investigated. According to the phase composition analyzed by X-ray powder diffraction, there is no crystalline phase except Ba2Ca(BO3)2 in the sample. Ba2Ca(BO3)2:Dy3+ can produce white emission under 348 nm excitation. The emission intensities of Ba2Ca(BO3)2:Dy3+ are affected by Dy3+ concentration. The concentration quenching effect was analyzed, and the concentration quenching mechanism was verified as dipole-dipole interaction. The critical distance(R c) obtained based on the crystal structure data is 2.911 nm. At 150℃, the emission intensity of Ba2Ca(BO3)2:Dy3+ is 68.0% of the initial value at room temperature. The activation energy for the thermal quenching calculated is 0.202 e V. Moreover, the CIE chromaticity coordinates of Ba2Ca(BO3)2:Dy3+ locate in the white region of(0.319, 0.356).
