光热反射实验中微弱信号的测量

介绍了用激光光热反射方法测量表面下物体热物性的实验原理.分析了实验中噪声的主要来源,运用带通滤光片结合差分探测的方式降低激光器产生的噪声.锁相放大技术对被测信号进行窄带放大,锁相放大器结合示波器输出了被测信号的周期变化部分,实现了光热法测量中微弱信号的测量.     

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.     

Multivariate temporal disaggregation with cross-sectional constraints

Multivariate temporal disaggregation deals with the historical reconstruction and nowcasting of economic variables subject to temporal and contemporaneous aggregation constraints. The problem involves a system of time series that are related not only by a dynamic model but also by accounting constraints. The paper introduces two fundamental (and realistic) models that implement the multivariate best linear unbiased estimation approach that has potential application to the temporal disaggregation of the national accounts series. The multivariate regression model with random walk disturbances is most suitable to deal with the chained linked volumes (as the nature of the national accounts time series suggests); however, in this case the accounting constraints are not binding and the discrepancy has to be modeled by either a trend-stationary or an integrated process. The tiny, compared with other driving disturbances, size of the discrepancy prevents maximum-likelihood estimation to be carried out, and the parameters have to be estimated separately. The multivariate disaggregation with integrated random walk disturbances is suitable for the national accounts aggregates expressed at current prices, in which case the accounting constraints are binding.     

A modification of the Whittaker–Henderson method of graduation

This paper presents a modified Whittaker–Henderson (WH) Method of Graduation. After giving a closed-form solution, we show that it is of practical use because it provides not only a smoothed series identical to that of the WH graduation, but also an extrapolation beyond the sample limit of current data. In addition, we introduce two other penalized least squares problems and show that they provide the same results as those of the modified WH graduation.     

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.