An alternative derivation of the Kalman filter using the quasi-likelihood method

The Kalman filter gives a recursive procedure for estimating state vectors. The recursive procedure is determined by a matrix, so-called gain matrix, where the gain matrix is varied based on the system to which the Kalman filter is applied. Traditionally the gain matrix is derived through the maximum likelihood approach when the probability structure of underlying system is known. As an alternative approach, the quasi-likelihood method is considered in this paper. This method is used to derive the gain matrix without the full knowledge of the probability structure of the underlying system. Two models are considered in this paper, the simple state space model and the model with correlated between measurement and transition equation disturbances. The purposes of this paper are (i) to show a simple way to derive the gain matrix; (ii) to give an alternative approach for obtaining optimal estimation of state vector when underlying system is relatively complex.     

调频广播用数字立体声编码器的数字内插处理

介绍了采用ＤＳＰ芯片ＴＭＳ３２０Ｃ５０及高速Ａ／Ｄ芯片实现的调频广播用的数字调频立体声编码器及其结构。研究了数字内插器的实现方法，讨论了基于凯泽窗的半带滤波器的设计步骤。该数字化方案不仅改善了音质，提高了立体声通道隔离度，而且减少了运算量，便于工程实现，并给出了实验测试结果。     

基于FPGA的生命探测仪算法研究与系统设计

给出了一种基于FPGA的生命探测信号处理系统的设计方法。从理论上研究了生命探测仪的算法及其软硬件系统。其中在FPGA软件设计中利用模块化的思想方法分别设计了FIR滤波器、异,~FIFO、UART．电池监控、功能控制等功能模块。最后完成人体特征信号和体动信号的分析与提取，实现了非接触情况下生命探测与发现。相对于传统的生命探测仪，该设备具有体积小，功耗低，操作简单，携带方便等优点，特别适用于野外和战场生命探测等应用场合。     

情感过滤因素与第二语言习得

本文从理论上对动力、态度、自我、移情、焦虑等影响第二语言习得的五大情感因素进行了探讨,指出这些因素不仅是目标语学习的促进剂,也是抑制剂。由此提出在第二语言学习和课堂教学中应从如何培养学习者正确的学习态度和学习动力,使他们树立语言、文化平等概念,以及创建和谐的语言学习环境等方面入手,减少情感过滤对第二语言习得过程和结果所产生的负面影响。     

情感因素与外语教学

在外语教学中,正确运用情感因素,充分重视并处理好教学中教师和学生的情感过滤问题,有助于师生之间的情感交流和教学效果的提高。     

重视语言教与学中的“情感过滤”

本文在简要论述什么是第二语言习得及二语习得理论对语言教师实践的重要意义的基础上,着重探讨了二语习得中情感因素的研究成果,特别是"情感过滤"现象的存在对外语教与学的启示.     

基于理性依赖理论的吸烟与居民医疗保健支出研究

根据Becker-Murphy(1988)和Chaloupka(1991)理性依赖行为理论推导的医疗保健支出模型表明,卷烟消费及其依赖性对居民医疗保健支出具有重要影响.采用1997～2002年相关数据进行的实证分析显示,卷烟消费及其依赖性与居民医疗保健支出正相关,且后者的影响更大更为显著.提高目前偏低的卷烟税率既能弥补吸烟的负外部性,也能有效地促进公共健康.     

一种双星定位与捷联惯性的融合方法

捷联惯性导航系统的主要缺点是导航定位误差随时间增长,双星定位系统是一种区域性卫星定位系统,可输出较高精度的水平位置,然而双星定位系统具有位置滞后与用户隐蔽性差的特点,针对其位置滞后现象研究了捷联惯性导航系统与双星定位系统进行组合的滤波方法,提出了其量测噪声的统计模型,同时设计其组合的时机以弥补系统的隐蔽性差的问题。仿真结果表明该滤波方法可行,具有较好的工程应用价值。     

A UNIFIED FRAMEWORK FOR MODELLING WILDLIFE POPULATION DYNAMICS†

This paper proposes a unified framework for defining and fitting stochastic, discrete‐time, discrete‐stage population dynamics models. The biological system is described by a state‐space model, where the true but unknown state of the population is modelled by a state process, and this is linked to survey data by an observation process. All sources of uncertainty in the inputs, including uncertainty about model specification, are readily incorporated. The paper shows how the state process can be represented as a generalization of the standard Leslie or Lefkovitch matrix. By dividing the state process into subprocesses, complex models can be constructed from manageable building blocks. The paper illustrates the approach with a model of the British grey seal metapopulation, using sequential importance sampling with kernel smoothing to fit the model.     

基带升余弦谱波形的数字实现及其分析

介绍了二进制横向滤波器(BTF)直接实现数据限带传输升余弦谱脉冲波形成形的方法。着重研究了影响横向滤波器结构的参数(每波特内取样数 K,单位冲激响应波形旁瓣数 L)与BTF 的阻带衰减和所形成升余弦谱信号在最坏情况下的码间干扰之间的关系,为优化工程设计提供了依据。最后给出了数值实例和实验结果。