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481.
介绍了6S管理的基本内容和具体实施标准,论述了推行6S管理对防化科研工作的重要意义,探讨了实施过程中应把握的问题。 相似文献
482.
在太赫兹频段,研究金属目标表面粗糙度对雷达散射截面(Radar Cross Section,RCS)的调制作用,对粗糙金属目标的RCS缩比测量具有重要意义.通过研究太赫兹粗糙金属目标镜面RCS随粗糙度的变化规律,结合相干、非相干散射理论,在基尔霍夫近似法的基础上,提出一种特定参数区间粗糙金属目标镜面RCS的预估方法,并... 相似文献
483.
484.
介绍了作者研制的通用CNC系统,该系统以AST386作为控制器,采用PWM驱动直流伺服电机,并配以软、硬件接口;文中对该系统的主要组成部分作了分析,在此基础上应用传统的PID控制方法设计数字控制器;最后通过实验验证了该系统的输出响应和控制器的性能。 相似文献
485.
针对评估对象的模糊性和不确定性,对层次分析法进行了改进,并提出了基于改进的层次分析法的装甲分队火力运用评估模型。在层次分析法基础上引入模糊集,并结合模糊评判,对装甲分队火力运用的能力进行了评估。结果表明,采用该方法进行的评估,有效避免了使用传统AHP方法构建判断矩阵时,专家对各标度间的区分把握不够准确,带来的评判误差,并取得了符合实际而又较为准确的评估结果。 相似文献
486.
C^4ISR系统通信网络效能评估指标体系研究 总被引:15,自引:1,他引:14
本文首先对C4ISR系统通信网络进行效能分析,提出C4ISR系统通信网络效能指标体系的研究途径,由此划分C4ISR系统通信网络效能指标体系为基本业务性能指标和战术性能指标两大类指标,给出各类指标的相关因素和求解方式,从而建立了一个评估C4ISR系统通信网络综合效能指标体系。 相似文献
487.
He-yang Xu Wei-bing Li Wen-bin Li Qing Zhang Ya-jun Wang Xiao-wen Hong Ying Yang 《防务技术》2021,17(5):1650-1659
The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated. A self-designed detonation wave regulator was used to control the detonation and cut the shell. It was found that the self-designed regulator controlled the fragment shape. The macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism, the shell fractured not only at the position of detonation collision, but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet (C-J) wave. The effects of groove number and outer layer thickness on the fracture behavior were tested by simulations. When the thickness of the outer layer was 5–18 mm, it has little effect on fragmentation of the shell, and shells all fractured at similar positions. The increase of the groove number reduced the fracture possibility of the first contact position of the C-J wave. When the groove number reached 7 with a 10 mm outer layer (1/4 model), the fracture only occurred at the position of detonation collision and the fragment width rebounded. 相似文献
488.
Tracking maneuvering target in real time autonomously and accurately in an uncertain environment is one of the challenging missions for unmanned aerial vehicles(UAVs).In this paper,aiming to address the control problem of maneuvering target tracking and obstacle avoidance,an online path planning approach for UAV is developed based on deep reinforcement learning.Through end-to-end learning powered by neural networks,the proposed approach can achieve the perception of the environment and continuous motion output control.This proposed approach includes:(1)A deep deterministic policy gradient(DDPG)-based control framework to provide learning and autonomous decision-making capa-bility for UAVs;(2)An improved method named MN-DDPG for introducing a type of mixed noises to assist UAV with exploring stochastic strategies for online optimal planning;and(3)An algorithm of task-decomposition and pre-training for efficient transfer learning to improve the generalization capability of UAV's control model built based on MN-DDPG.The experimental simulation results have verified that the proposed approach can achieve good self-adaptive adjustment of UAV's flight attitude in the tasks of maneuvering target tracking with a significant improvement in generalization capability and training efficiency of UAV tracking controller in uncertain environments. 相似文献
489.
Hong-bin Xie Hui-ya Yang Jian Yu Ming-yu Gao Jian-dong Shou You-tong Fang Jia-bin Liu Hong-tao Wang 《防务技术》2021,17(2):429-439
Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and obscurity.It is found that the rail should withstand huge mechanical and thermal shocks during the launching operation.The forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,etc.The service life of the rail has become a bottleneck restricting the development of elec-tromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail materials.This paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and properties.We begin from a short background of the requirement of the rail material.Then a detailed investigation of rail materials is described,and the performances of those materials are introduced.Finally,further development prospect of rail material is discussed. 相似文献
490.
For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang-bang evasive maneuver with a random switching time. Combined Fast multiple model adaptive estimation (Fast MMAE) algorithm, the cooperative guidance law takes detection configuration affecting the accuracy of interception into consideration. Introduced the detection error model related to the line-of-sight (LOS) separation angle of two interceptors, an optimal cooperative guidance law solving the optimization problem is designed to modulate the LOS separation angle to reduce the estimation error and improve the interception performance. Due to the uncertainty of the target bang-bang maneuver switching time and the effective fitting of its multi-modal motion, Fast MMAE is introduced to identify its maneuver switching time and estimate the acceleration of the target to track and intercept the target accurately. The designed cooperative optimal guidance law with Fast MMAE has better estimation ability and interception performance than the traditional guidance law and estimation method via Monte Carlo simulation. 相似文献