某型自行火炮负重轮轴承的模糊可靠性分析

负重轮轴承的可靠度直接影响到履带式自行火炮的机动性能。综合考虑轴承在制造和使用过程中的各种因素,结合自行火炮的典型任务剖面,运用模糊数学和可靠性理论,对某型履带式自行火炮负重轮轴承的可靠度进行了分析。     

自行火炮路面振动信号时频特性研究

自行火炮越野行驶减速停车过程车体的振动是非平稳的,传统的信号处理方法难以得出更多有用信息。利用连续小波变换在时域和频域具有的良好局部化特性,结合传统信号分析手段,对某型自行火炮减速停车过程的振动加速度信号进行了时频分析,研究了自行火炮的非平稳振动特性。结果表明：车体振动加速度的幅值和频率均随车速的提高而增大,采样信号小波系数灰度图给出了火炮振动特征随时间和频率的变化规律,克服了传统分析方法的不足。另外,实施了连续小波变换尺度的非等间隔选取,在不影响低频分析准确性的同时,处理结果对分析信号高频成分非常有效。     

基于ARM7的自行火炮火控系统测控平台研究

自行火炮是当今世界各国地面压制火力的重点装备,火控系统作为自行火炮的重要组成部分,对于火炮的远程射击和精确命中至关重要;当前,专用维修检测设备的缺乏给自行火炮火控系统的装备保障带来较大困难;在对部队装备维修的实际需要、装备维修的特点以及基于ARM7的嵌入式系统等进行深入分析研究的基础上,设计了一套基于ARM7的自行火炮火控系统综合测控平台;平台集测试与控制、故障诊断和专家系统、远程支援、信息管理于一体,为装备使用和维修人员实施快速、高效的保障提供了很好的硬件和软件环境;使用表明,测控平台提高了装备保障的效益和效率。     

基于ZigBee的自行火炮定位布阵系统研究

根据现代高技术战争条件下的作战需要,提出一种基于ZigBee的自行火炮定位布阵系统。以ZigBee为基础,构建火炮定位无线网络系统,实现火炮战地实时定位布阵。采用自适应随机布阵技术,完成实战火炮群的灵活布阵。研究基于ZigBee的火炮布阵网络边界条件,保证实战布阵组网的可行性。采用可替补的主从网络,确保作战指令的统一性。该系统可以应用于营连等单位的快速定位,可实现快速转移和快速进入阵地,提高部队的战斗力。     

Modelling and analysis of bacterial tracks suggest an active reorientation mechanism in Rhodobacter sphaeroides

Most free-swimming bacteria move in approximately straight lines, interspersed with random reorientation phases. A key open question concerns varying mechanisms by which reorientation occurs. We combine mathematical modelling with analysis of a large tracking dataset to study the poorly understood reorientation mechanism in the monoflagellate species Rhodobacter sphaeroides. The flagellum on this species rotates counterclockwise to propel the bacterium, periodically ceasing rotation to enable reorientation. When rotation restarts the cell body usually points in a new direction. It has been assumed that the new direction is simply the result of Brownian rotation. We consider three variants of a self-propelled particle model of bacterial motility. The first considers rotational diffusion only, corresponding to a non-chemotactic mutant strain. Two further models incorporate stochastic reorientations, describing ‘run-and-tumble’ motility. We derive expressions for key summary statistics and simulate each model using a stochastic computational algorithm. We also discuss the effect of cell geometry on rotational diffusion. Working with a previously published tracking dataset, we compare predictions of the models with data on individual stopping events in R. sphaeroides. This provides strong evidence that this species undergoes some form of active reorientation rather than simple reorientation by Brownian rotation.     

Interaction rules underlying group decisions in homing pigeons

Travelling in groups gives animals opportunities to share route information by following cues from each other''s movement. The outcome of group navigation will depend on how individuals respond to each other within a flock, school, swarm or herd. Despite the abundance of modelling studies, only recently have researchers developed techniques to determine the interaction rules among real animals. Here, we use high-resolution GPS (global positioning system) tracking to study these interactions in pairs of pigeons flying home from a familiar site. Momentary changes in velocity indicate alignment with the neighbour''s direction, as well as attraction or avoidance depending on distance. Responses were stronger when the neighbour was in front. From the flocking behaviour, we develop a model to predict features of group navigation. Specifically, we show that the interactions between pigeons stabilize a side-by-side configuration, promoting bidirectional information transfer and reducing the risk of separation. However, if one bird gets in front it will lead directional choices. Our model further predicts, and observations confirm, that a faster bird (as measured from solo flights) will fly slightly in front and thus dominate the choice of homing route. Our results explain how group decisions emerge from individual differences in homing flight behaviour.     

扭力轴多工况二维随机疲劳载荷谱的编制

扭力轴用来减轻自行火炮在行驶过程中地面对车体的冲击。针对扭力轴扭矩载荷谱多工况和非对称的特点，进行单一工况雨流法计数载荷循环、单一工况载荷的分布规律与检验、各工况频次向寿命周期扩展、载荷分级与级循环次数的计算、载荷谱列表。编谱过程基本上包括了多工况非对称型载荷编谱的所有步骤，对编制其它受多工况非对称型载荷的构件的疲劳载荷谱也有参考价值。     

CAN总线在自行火炮监测系统中的应用设计

设计了一套基于CAN（controller area network）总线的自行火炮监测数据采集系统，解决了目前监测布线复杂、可靠性低、不适于营连成网的问题。系统由6大部分和若干可增减的CAN节点组成，分别对自行火炮的底盘技术状态信息和武器系统状态信息进行监测，主控PC机用PC—CAN适配卡与各个节点通信，并完成CAN节点、PC-CAN适配卡的软、硬件设计和整个系统的调试工作。     

基于CBR-ANN的自行火炮故障诊断系统

针对自行火炮维修保障中存在大量维修案例没有被记录和整理、维修中故障诊断效率低等现状和诸多不足，提出了将人工智能中的基于案例推理技术（CBR）与人工神经网络技术（ANN）相结合（即CBR—ANN）应用于自行火炮的故障诊断中，建立了故障诊断系统；同时对诊断系统中的几个关键技术——案例的混合聚类模型、案例的表达及基于3层BP神经网络的案例索引进行了设计和说明。该系统的完善和应用有利于提高自行火炮的维修保障能力。     

自行火炮综合体使用质量指标对其效能影响分析

武器装备效能评估是武器论证和作战使用领域的重要研究内容。目前，大量具有先进水平的新型自行火炮已装备部队。它们是由功能相互关联的武器系统、车载设备、自动化指挥设备、综合保障设备等构成的自行火炮综合体。诸如射击准备时间、自行火炮装备完好性程度等作战准备性能直接影响着自行火炮综合体作战效能．传统的效能评估方法很难准确地评估其效能。从系统论角度出发，研究了自行火炮综合体的使用性能对其作战能力的影响，并建立了分析模型。