P3.18. An analog signal xa(t) = sin (100πt) is sampled using the following sampling intervals. In each case plot the spectrum of the resulting discrete-time signal. Ts= 0.1 ms, Ts= 1 ms, Ts = 0.01 Sec

建立一个矩阵，进行一些运算，求得XA=B中X的值-matrix caculation

从空中水平抛射出的物体，初始水平速度Vx(0)，初始位置坐标(x(0),y(0))；受重力g和阻尼力影响，阻尼力与速度平方成正比，水平和垂直阻尼系数分别为Kx,Ky,；还存在不确定的零均值白噪声干扰力xa和ya。在坐标原点处有一观测设备(不妨想象成雷达)，可测得距离r(零均值白噪声误差r)、角度(零均值白噪声误差)，使用扩展卡尔曼滤波进行仿真。-The level of throwing objects the air, the speed of the initial level of Vx

等温式反应器的管长计算，数值积分求L，计算平衡转化率xA.-Isothermal reactor tube length calculations, numerical integration seek L, calculated equilibrium conversion xA.