
检测技术习题及参考答案.doc
31页检测技术习题及参考答案第三章 检测装置的基本特性3.1(教材18.8) 由测量方程:3x+y=2.9,x-2y=0.9,2x-3y=1.9,试用最小二乘法求x、y的值解:根据测量方程可写出以下几个矩阵:实测值矩阵,系数矩阵,估计值矩阵令, 即x=0.963,y=0.01523.2(教材18.9) 某电路的电压数值方程为U=I1R1+I2R2,当电流I1=2A、I2=1A时,测得电压U=50V;当电流I1=3A、I2=2A时,测得电压U=80V;当电流I1=4A、I2=3A时,测得电压U=120V试用最小二乘法求两只电阻R1、R2的测量值解:测量方程为 根据测量方程可写出以下几个矩阵:实测值矩阵,系数矩阵,估计值矩阵令, 即R1=13.33Ω,R2=21.67Ω3.3(教材18.10) 通过某检测装置测得的一组输入输出数据如下表所示试用最小二乘法拟合直线,试求其线性度和灵敏度输入x0.82.53.34.55.76.8输出y1.11.52.63.24.05.0解:设回归方程为 可用代数法和矩阵法两种方法进行回归分析。
1)用代数法进行回归分析先用表格进行数据处理ixyx2y2xy10.81.10.641.210.8822.51.56.252.253.7533.32.610.896.768.5844.53.220.2510.2414.4055.74.032.4916.0022.8066.85.046.2425.0034.00∑23.617.4116.7661.4684.41列表计算, 回归方程为(2)用矩阵法进行回归分析根据测量数据可写出以下两个矩阵:实测值矩阵,结构矩阵正规方程系数矩阵相关矩阵正规方程常数项矩阵回归系数矩阵即回归系数b0=0.277,b1=0.667回归方程为可见用代数法和矩阵法两种方法进行回归分析所得回归方程是相同的3)求灵敏度取回归方程的斜率作为灵敏度,即S=0.667(4)求线性度利用回归方程计算各点的估计值和误差值,填入下表xi0.82.53.34.55.76.8yi1.11.52.63.24.05.00.811.942.483.284.084.810.29-0.440.12-0.08-0.080.19取误差的最大绝对值最小二乘线性度3.4(教材18.11) 有一只压力传感器的标定数据如下表所示,试用最小二乘法求其线性度和灵敏度。
xi/103Pa00.51.01.52.0正行程yi/V0.00200.20150.40050.60000.7995反行程yi/V0.00300.20200.40200.60100.8005解:设回归方程为可用代数法和矩阵法两种方法进行回归分析1)用代数法进行回归分析先用表格进行数据处理ixyx2y2xy10.00.00200.000.000004000.0000020.00.00300.000.000009000.0000030.50.20150.250.040602250.1007540.50.20200.250.408004000.1010051.00.40051.000.160400250.4005061.00.40201.000.161604000.4020071.50.60002.250.360000000.9000081.50.60102.250.361201000.9015092.00.79954.000.639200251.59900102.00.80054.000.640800251.60100∑10.04.012015.002.404625006.00575列表计算, 回归方程为(2)用矩阵法进行回归分析根据测量数据可写出以下两个矩阵:实测值矩阵,结构矩阵正规方程系数矩阵相关矩阵 正规方程常数项矩阵回归系数矩阵 即回归系数 b0=0.00245,b1=0.39875回归方程为 (3)求灵敏度取回归方程的斜率作为灵敏度,即S=0.39875V/103Pa(4)求线性度利用回归方程计算各点的估计值,正反行程平均值和误差值,填入下表。
xi00.51.01.52.00.00250.201750.401250.60050.80000.002450.2018250.401200.605750.799950.00005-0.0000750.00005-0.0000750.00005取误差的最大绝对值 最小二乘线性度 3.5(教材2.3) 利用压力传感器所得的测试数据如下表所示,计算其非线性误差、迟滞和重复性误差设压力为0MPa时输出为0mV,压力为0.12MPa时输出最大且为16.50mV压力xi/MPa输出值yi/mV第一循环第二循环第三循环正行程反行程正行程反行程正行程反行程0.020.560.660.610.680.640.690.043.964.063.994.094.033.110.067.407.497.437.537.457.520.0810.8810.9510.8910.9310.9410.990.1014.4214.4214.4714.4714.4614.46解:(1)计算端基线性度计算各点正反行程输出值的平均值,填入下表xi00.020.040.060.080.100.1200.644.047.4710.9314.4516.50端基直线的斜率 端基直线的方程为y=137.5x利用端基直线方程计算各点的估计值,计算误差值,填入下表。
xi00.020.040.060.080.100.1200.644.047.4710.9314.4516.5002.755.508.2511.0013.7516.500-2.11-1.46-0.78-0.070.700取误差的最大绝对值端基线性度 (2)计算最小二乘线性度用代数法进行回归分析设回归方程为先用表格进行数据处理ixyx2y2xy10000020.020.560.00040.31360.011230.020.660.00040.43560.013240.020.610.00040.37210.012250.020.680.00040.46240.013660.020.640.00040.40960.012870.020.690.00040.47610.013880.043.960.001615.68160.158490.044.060.001616.48360.1624100.043.990.001615.92010.1596110.044.090.001616.72810.1636120.044.030.001616.24090.1612130.044.110.001616.89210.1644140.067.400.003654.76000.4440150.067.490.003656.10010.4494160.067.430.003655.20940.4458170.067.530.003656.70090.4518180.067.450.003655.50250.4470190.067.520.003656.55040.4512200.0810.880.0064118.37440.8704210.0810.950.0064119.90250.8760220.0810.890.0064118.59210.8712230.0810.930.0064119.46490.8744240.0810.940.0064119.68360.8752250.0810.990.0064120.78010.8792260.1014.420.0100207.93641.4420270.1014.420.0100207.93641.4420280.1014.470.0100209.38091.4470290.1014.470.0100209.38091.4470300.1014.460.0100209.09161.4460310.1014.460.0100209.09161.4460320.1216.500.0144272.25001.9800∑1.92241.680.14642677.100019.6320列表计算, 回归方程为 利用回归方程计算各点的估计值,计算误差值,填入下表。
xi00.020.040.060.080.100.1200.644.047.4710.9314.4516.50-2.3150.9744.2637.55210.84214.13017.4202.。












