机械振动特征分析中的信号处理技术与微机特征分析系统

文中指出抑制阶比混迭和泄漏是建立一套完整的微机特征分析系统中需要解决的二个关键的信号处理问题。提出了阶比滤波器是抑制阶比混迭有效和实用的方法;并研制频率比合成器以抑制泄漏。介绍了由频率比合成器、阶比滤波器、TMS32010数据采集装置、主机和绘图仪所组成的微机特征分析系统。最后给出了该微机特征分析系统对轴承进行故障诊断的结果。     

带噪声的 AR 模型的参数估计及定阶

本文讨论了带噪声情形下 AR 模型的参数估计及定阶问题,还给出了噪声模型的参数估计,并证明了它们的强相容性。     

机载武器控制系统算法研究

机载武器控制系统的算法是其软件部分的核心,算法的最终目的是保证在一定的条件下实现最有利的武器运用方案。将机载武器控制系统的算法分为四个不同的子算法,对每一子算法的建立方法进行了描述,最后得到形成执行命令的算法,即武器运用方案执行命令分配及形成的算法。     

基于案例推理的指挥实体任务规划高维解空间适应性问题研究?

利用案例推理对指挥实体任务规划过程中决策问题求解方法的修正过程是该方法推理过程中最困难的阶段,尤其当决策问题解空间是多维的情况下。讨论了指挥实体任务规划过程中高维决策空间的修正问题,并提出了可行的解决方法。首先,利用自组织匹配法清晰展现问题空间与决策空间的映射过程,然后,利用反向传播神经网络分析匹配结果间的相关性问题,最后,选取一个简化的军事剧情对该方法的合理性进行验证。     

Numerical investigation of dynamic interaction with projectile and harmonic behaviour for T-finned machine gun barrels

Machine gun barrels differ from their rifle counterparts in terms of profile. To support high rates of sustained fire, machine gun barrels are made thicker in order to dissipate more heat and maintain their flexural rigidity and thus accuracy, but on other hand they also contribute in weight addition to weapon. This investigation deals with comparison between a conventional machine gun barrel and an improved innovative design having T-fins, both having same weight and chambered in 5.56 × 45 NATO ammunition, to compare their structural and harmonic characteristics which were parameterized by factors such as modal spectrum, directional deformation at muzzle ends during a single shot fire and harmonic behaviour at corresponding range of exciting frequencies. The solid models of both the barrels having same weight, were created using Solidworks. The continuous input data functions were generated by MATLAB using the field tested discreet data points. The generated velocity-distance functions were converted into time dependent functions using integration algorithms to calculate transient parameters such as time steps, excitation frequency range, angle of rotation of projectile and its angular velocity. The dynamic condition simulated the varying nature of forces due to eccentricity in projectile and this data was fed to a time step study using ANSYS transient structural work bench followed by modal and harmonic analysis. The results showed a significant reduction in muzzle end deformation which thus proved that the T-finned barrel, although had same weight as that of the conventional one, but had better structural and harmonic characteristics, and hence it would inherit better firing accuracy.     

基于旋转点电荷模型的舰船腐蚀电场

为了找出轴频电场无法彻底消除及实际测量中静电场产生波动曲线问题的原因,基于旋转点电荷的建模方法对舰船腐蚀电场进行研究。利用汉克尔变换对点电荷在三层介质中产生的电场进行近似求解,得出一定转速下感应电场随时间、螺旋桨半径及水面距离变化的规律曲线图,并通过实验验证了理论结果的正确性。结果表明:螺旋桨旋转产生的感应电场是构成舰船腐蚀电场的一部分,一定转速下的感应电场频率与螺旋桨转动频率一致,并会随着螺旋桨半径及与水面距离的增加而减小。     

一类非正态误差下的AR模型定阶研究

对一类非正态误差的AR模型,在待定阶数P的情况下,给出误差项中未知实函数依概率有界的定理,可把非正态误差转化为正态情况。最后运用正态误差下AR模型的方法确定阶数和参数,并给出一个算例。     

Dynamic capacity reservation and due date quoting in a make‐to‐order system

We consider a make‐to‐order manufacturer facing random demand from two classes of customers. We develop an integrated model for reserving capacity in anticipation of future order arrivals from high priority customers and setting due dates for incoming orders. Our research exhibits two distinct features: (1) we explicitly model the manufacturer's uncertainty about the customers' due date preferences for future orders; and (2) we utilize a service level measure for reserving capacity rather than estimating short and long term implications of due date quoting with a penalty cost function. We identify an interesting effect (“t‐pooling”) that arises when the (partial) knowledge of customer due date preferences is utilized in making capacity reservation and order allocation decisions. We characterize the relationship between the customer due date preferences and the required reservation quantities and show that not considering the t‐pooling effect (as done in traditional capacity and inventory rationing literature) leads to excessive capacity reservations. Numerical analyses are conducted to investigate the behavior and performance of our capacity reservation and due date quoting approach in a dynamic setting with multiple planning horizons and roll‐overs. One interesting and seemingly counterintuitive finding of our analyses is that under certain conditions reserving capacity for high priority customers not only improves high priority fulfillment, but also increases the overall system fill rate. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

GM(1,1)模型在装备备件订购中的应用

分析了武器装备备件订购决策的目标和常用方法,并运用灰色理论GM(1,1)模型及关联度分析法,提出了在军用备件订购工作中费用目标预测的应用方法,以及提高预测精度的措施。