小口径空炸射击高炮武器系统的点射毁伤概率

分析了各子系统所引起射击诸元误差分量的相关性和重复性;假定点射中射击诸元误差呈正态分布,随机生成射击诸元误差分量;根据射击诸元误差与射击误差的关系,计算射击误差;结合空炸毁伤定律,计算点射毁伤概率;通过算例,研究了弱相关误差的相关系数与点射毁伤概率的关系.     

基于物元分析的数字化坦克连火力打击能力评估

通过对数字化坦克连火力打击能力影响因素的分析,建立了对其进行评估的指标体系。基于物元分析理论,引入三标度法确定各指标的权重,构建了火力打击能力的评估模型,并结合具体实例验证了此模型的可行性和实用性。该方法能够有效结合定性与定量分析,且模型结构简单规范,为数字化坦克连火力打击能力的评估提供了一种较为有效的方法和途径。     

改进型部队综合战斗力指数评估方法与模型

针对传统的部队综合战斗力指数评估方法中出现的计算结果与实际结果有较大偏差的问题,分析了其产生的原因,然后根据“综合战斗力指数”及其相关概念的定义,对“火力指数”、“生存力指数”及“机动力指数”等概念的内涵和外延进行了新的界定,并进一步通过对部队作战能力的构成及因素分析,提出了部队综合战斗力指数评估方法,建立了相应的模型。     

An efficient SPH methodology for modelling mechanical characteristics of particulate composites

Particulate composites are one of the widely used materials in producing numerous state-of-the-art components in biomedical, automobile, aerospace including defence technology. Variety of modelling techniques have been adopted in the past to model mechanical behaviour of particulate composites. Due to their favourable properties, particle-based methods provide a convenient platform to model failure or fracture of these composites. Smooth particle hydrodynamics (SPH) is one of such methods which demonstrate excellent potential for modelling failure or fracture of particulate composites in a Lagrangian setting. One of the major challenges in using SPH method for modelling composite materials depends on accurate and efficient way to treat interface and boundary conditions. In this paper, a master-slave method based multi-freedom constraints is proposed to impose essential boundary conditions and interfacial displacement constraints in modelling mechanical behaviour of composite materials using SPH method. The proposed methodology enforces the above constraints more accurately and requires only smaller condition number for system stiffness matrix than the procedures based on typical penalty function approach. A minimum cut-off value-based error criteria is employed to improve the compu-tational efficiency of the proposed methodology. In addition, the proposed method is further enhanced by adopting a modified numerical interpolation scheme along the boundary to increase the accuracy and computational efficiency. The numerical examples demonstrate that the proposed master-slave approach yields better accuracy in enforcing displacement constraints and requires approximately the same computational time as that of penalty method.     

Adaptive phasefield modelling of crack propagation in orthotropic functionally graded materials

In this work, we extend the recently proposed adaptive phase field method to model fracture in orthotropic functionally graded materials (FGMs). A recovery type error indicator combined with quadtree decomposition is employed for adaptive mesh refinement. The proposed approach is capable of capturing the fracture process with a localized mesh refinement that provides notable gains in computational efficiency. The implementation is validated against experimental data and other nu-merical experiments on orthotropic materials with different material orientations. The results reveal an increase in the stiffness and the maximum force with increasing material orientation angle. The study is then extended to the analysis of orthotropic FGMs. It is observed that, if the gradation in fracture properties is neglected, the material gradient plays a secondary role, with the fracture behaviour being dominated by the orthotropy of the material. However, when the toughness increases along the crack propagation path, a substantial gain in fracture resistance is observed.     

Survivability assessment of spacecraft impacted by orbit debris

To help optimize the spacecraft design and reduce the risk of spacecraft mission failure, a new approach to assess the survivability of spacecraft in orbit is presented here, including the following three steps:1) Sensitivity Analysis of spacecraft. A new sensitivity analysis method, a ray method based on virtual outer wall, is presented here. Using rays to simulate the debris cloud can effectively address the component shadowing issues. 2) Component Vulnerability analysis of spacecraft. A function"Component functional reduction degree — Component physical damage degree"is provided here to clearly describe the component functional reduction. 3) System-level Survivability Assessment of spacecraft. A new method based on expert knowledge reasoning, instead of traditional artificial failure tree method, is presented here to greatly improve the efficiency and accuracy of calculation.     

数字通信及状态相关方法在线缆测试中的应用

给出了基于串行数字通信及状态相关的线缆测试方法。对舰艇作战系统中各分系统、设备之间互连的电缆线路进行快速测试,通过对芯线状态测试矩阵的逻辑处理和变换,能准确地得到芯线状态的检查结果。实验表明:这种方法能大大提高对舰艇作战系统中各分系统、设备之间互连的电缆线路的检查维修效率。     

空军网络化指挥信息系统作战效能评估指标体系构建

针对目前网络化指挥信息系统作战效能评估指标体系不完善、且缺乏分项指标计算方法模型等问题,从网络化作战对指挥信息系统的作战需求出发,研究构建了空军网络化指挥信息系统的作战效能评估指标体系,并提出了分项指标概念内涵和计算模型与方法,可为指挥信息系统研制提供参考和支撑,为其作战效能的客观评估提供指标体系和模型方法。     

SiO_2在SHS铝热-重力分离法制备陶瓷内衬复合钢管中的作用

采用自蔓延铝热-重力分离法,制备了陶瓷内衬复合钢管,并系统研究了SiO_2添加剂对SHS燃烧过程、陶瓷层相对密度与组织结构、复合钢管力学性能的影响。经研究发现,SiO_2在铝热燃烧过程中作为稀释剂存在,随着SiO_2添加量增多,燃烧温度与蔓延速率下降,并使分布于α-Al_2O_3枝晶晶界处的亚稳定相FeO·Al_2O_3增多;陶瓷相对密度与复合钢管抗压溃强度在SiO_2含量为2wt％时出现极大值(分别为92.5％与430MPa);陶瓷硬度、断裂韧性与复合钢管抗压剪强度随SiO_2含量增加而降低。