基于SystemView的4位m序列发生器数学模型的分析及电路设计

通过对m序列的数学模型研究分析,运用System View软件进行了4级移位寄存器模型的仿真,并对4位m序列生成器电路进行了设计研究,探讨了实现m序列的生成过程。仿真表明所设计的电路合理,其结果与理论分析一致。     

Adaptive model predictive inventory controller for multiproduct batch plant

An inventory control system was developed for multiproduct batch plants with an arbitrary number of batch processes and storage units. Customer orders are received by the plant at order intervals and in order quantities that are subject to random fluctuations. The objective of the plant operation is to minimize the total cost while maintaining inventory levels within the storage or warehouse capacity by adjusting the startup times, the quantities of raw material orders, and production batch sizes. An adaptive model predictive control algorithm was developed that uses a periodic square wave model to represent the flows of the material between the processes and the storage units. The boundedness of the control output and the convergence of the estimated parameters in implementations of the proposed algorithm were mathematically proven under the assumption that disturbances in the orders are bounded. The effectiveness of this approach was demonstrated by performing simulations. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1867–1880, 2015     

基于空间直角坐标系的逆变器调制波研究

基于空间直角坐标系,对逆变器三相调制波进行研究,提出三维空间调制波矢量的概念并讨论其特点。利用调制波矢量得到了SPWM和SVPWM的解析表达式,使调制方法、控制策略、主电路成为一个整体,便于进行统一建模,具有几何含义清晰、理解直观、计算简单等优点。利用Matlab/Simulink进行仿真和逆变器平台进行实验,结果证明研究方法正确有效。     

Time‐domain hybrid formulations for wave simulations in three‐dimensional PML‐truncated heterogeneous media

We are concerned with the numerical simulation of wave motion in arbitrarily heterogeneous, elastic, perfectly‐matched‐layer‐(PML)‐truncated media. We extend in three dimensions a recently developed two‐dimensional formulation, by treating the PML via an unsplit‐field, but mixed‐field, displacement‐stress formulation, which is then coupled to a standard displacement‐only formulation for the interior domain, thus leading to a computationally cost‐efficient hybrid scheme. The hybrid treatment leads to, at most, third‐order in time semi‐discrete forms. The formulation is flexible enough to accommodate the standard PML, as well as the multi‐axial PML. We discuss several time‐marching schemes, which can be used à la carte, depending on the application: (a) an extended Newmark scheme for third‐order in time, either unsymmetric or fully symmetric semi‐discrete forms; (b) a standard implicit Newmark for the second‐order, unsymmetric semi‐discrete forms; and (c) an explicit Runge–Kutta scheme for a first‐order in time unsymmetric system. The latter is well‐suited for large‐scale problems on parallel architectures, while the second‐order treatment is particularly attractive for ready incorporation in existing codes written originally for finite domains. We compare the schemes and report numerical results demonstrating stability and efficacy of the proposed formulations. Copyright © 2014 John Wiley & Sons, Ltd.     

假目标散射特性对激光有源诱偏效果的影响

针对假目标散射特性对激光有源诱偏干扰效果的影响,提出了假目标激光散射特性的测量方法,实际测量了常见典型假目标的激光散射特性,得到了不同类型假目标对激光的散射规律。结果表明,利用假目标对激光制导武器进行有源诱偏干扰时,首先应选择散射系数较高的假目标,同时要依据假目标的散射特性确定干扰激光的照射部位,确保尽可能强的干扰激光信号进入导引头系统,形成有效诱偏干扰。