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本文介绍一种用于具有附加高斯噪声的一般非线性量测模型的分布式参数估计算法。我们证明:当扩展为多传感器情况得出一个线性融合规则时,由Kulhavy′提出的贝叶斯-闭式估计算法与局部的后验密度的形式无关。特别是Kulhavy′算法产生一组表示局部传感器密度的简化的充分统计量(RSS),这是在全局处理机中进行简单地相加和相减而获得最优融合。我们讨论了关于贝叶斯-闭式算法的各种近似值,得到非线性量测模型的实际参数估计器,并将这种近似技术应用于纯方位跟踪问题。把分布式跟踪器的性能与基于在修正的极坐标(MPC)中实现的广义卡尔曼滤波器(EKF)的另一种算法作了比较。已经证明:从通常的EKF意义上讲,贝叶斯-闭式估计器没有发散,因此在单向和双向发送方式中都可以利用贝叶斯-闭式技术。 相似文献
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潜在故障状态可测的一种故障检查模型 总被引:1,自引:0,他引:1
从系统的功能故障状态和潜在故障状态两方面讨论了故障检查模型,基于延迟时间模型推导了系统的期望可用度模型并对其适用性进行了讨论与验证。 相似文献
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Explosive welding technique is widely used in many industries. This technique is useful to weld different kinds of metal alloys that are not easily welded by any other welding methods. Interlayer plays an important role to improve the welding quality and control energy loss during the collision process. In this paper, the Ti6Al4V plate was welded with a copper plate in the presence of a commercially pure titanium interlayer. Microstructure details of welded composite plate were observed through optical and scanning electron microscope. Interlayer-base plate interface morphology showed a wavy structure with solid melted regions inside the vortices. Moreover, the energy dispersive spectroscopy analysis in the interlayer-base interface reveals that there are some identified regions of different kinds of chemical equilibrium phases of Cu–Ti, i.e. CuTi, Cu2Ti, CuTi2, Cu4Ti, etc. To study the mechanical properties of composite plates, mechanical tests were conducted, including the tensile test, bending test, shear test and Vickers hardness test. Numerical simulation of explosive welding process was performed with coupled Smooth Particle Hydrodynamic method, Euler and Arbitrary Lagrangian-Eulerian method. The multi-physics process of explosive welding, including detonation, jetting and interface morphology, was observed with simulation. Moreover, simulated plastic strain, temperature and pressure profiles were analysed to understand the welding conditions. Simulated results show that the interlayer base plate interface was created due to the high plastic deformation and localized melting of the parent plates. At the collision point, both alloys behave like fluids, resulting in the formation of a wavy morphology with vortices, which is in good agreement with the experimental results. 相似文献
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中央党校第期地厅级A班学员课题组 《中国军转民》2009,(1):46-50
国内非公经济迅猛发展及其特殊优势.使其具备了参与国防科研生产的能力和条件,并正在成为国防工业的重要组成部分和国防现代建设的重要推动力量。目前一些非公企业在市场机制驱动下通过一些“历史渠道”、“跳窗户”或“开后门”已进入国防科研领域,但只是一股被边缘化的生产力,与它快速增长的发展规模和贡献很不相称,并且只局限在“技术参与”范畴,仅限于对某些产品和技术的补充,全面参与国防建设还存在观念、体制和机制等诸多障碍。
政府主管部门要转变观念和职能,加强对非公经济的公共服务和市场监管,建立和完善相应的政策法规、制度和程序,依法维护非公企业从事军品科研活动的正当权益。 相似文献
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The following article tests the hypothesis that veterans have better health if they were officers when they were in the U.S. military than if they served in the enlisted ranks. It examines this hypothesis by presenting results from logistic regressions that are based on four surveys: the National Survey of Veterans, the Survey of Retired Military, the Panel Study of Income Dynamics, and the Wisconsin Longitudinal Study. In all four of these surveys, the evidence is consistent with the hypothesis that military rank is associated with health, particularly among veterans who served longer. It also suggests that the health gradient by rank is independent of similar gradients by education and income as well as health differences by race. These findings indicate that health may be influenced not just by differences in civilian society but also by those in the military. 相似文献