When the measured peaks, it is mostly due to md can be corrected by 2. The sampling factor generally used in NVH measurement is equal to (A) 2.0, (B) 2.56, or (C) 3.0 times the maximum frequency of the signal.
With the Nyquist frequency set at 3200 Hz and spectral line at 800 lines, (A) the frequency resolution will be 4 Hz, (B) the time record is 0.5 sec, (C) the sampled data points are 2048. When aliasing exists, i.e. the sampling frequency is too slow, the amplitude and frequency errors are due to and can be corrected by (A) and (B).
The common feature of most time windows is (A) down weighting the time signal at leading stage, (B) down weighting the time signal at trailing stage, or (C) down weighting the time signal at both leading and trailing stage. Hanning window is generally used for (A) impact signals, (B) calibration, or (C) continuous signal. In order to reduce the leakage error during engine noise testing, the engineer will most probably use (A) a linear (rectangular), (B) a transient, or (C) a Hanning window. The main purpose of using overlapping averaging is to (A) reduce measurement time for more averages, (B) increase measurement time for more averages, or (C) increase time block of each sampling. During an impact testing, the engineer will use (A) positive time delay, (B) negative time delay, or (C) no time delay to capture the whole signal.
The inverse Fourier transform of an auto power spectrum will be (A) average time function, (B) auto-correlation function, or (C) instantaneous time function. The averaged cross power spectrum (A) will not remove all noise, or (B) will increase noise. In order to compensate for the propagation time from the input to the output during full vehicle FRF testing, the engineer may use (A) auto correlation, (B) cross correlation to determine the time delay. The FRF H2 will most likely give a bias-high value because (A) it has noise in the input, (B) it has noise in the output, or (C) it has noise in both input and output signals. The firing order of a 6 cylinder two-stroke diesel engine will be (A) sixth order, (B) second order, or (C) third order. Csptsum is generated by inverting and its unit is.