A New Method to Measure LF Time Code Service Signal Based on Virtual Instrument

The conventional way of separating the vibration signals of the inner and outer rotors of a dual-rotor system is to separate the composite "beat" signal; however, this is not effective for a dual-rotor system with little speed difference. We propose a new method of separating the vibration signals of the inner and outer rotors of a system with veiy little speed difference. It is not necessary to separate the composite " beat" signal, as in the conventional method. The magnitude and phase values of the unbalanced weights are obtrined directly by sampling the vibration signal synchronized with a reference signal. The balancing process is completed by the reciprocity influence coefficients of the method of the inner and outer rotors. The results show the advantage of such a method for a dual-rotor system, compared with conventional balancing. The proposed new method has been successfully implemented in field dynamic balancing of the centrifuge with such dual-rotor systems in two rectifying planes with digital signal processing and virtual instrument technology.

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Research on Key Technologies of Signal Processing in Automobile Performance Virtual Detection System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.963 ◽

2012 ◽

Vol 562-564 ◽

pp. 963-967

Author(s):

Ping Wu

Keyword(s):

Signal Processing ◽

Virtual Instrument ◽

Performance Test ◽

Detection System ◽

High Accuracy ◽

Test System ◽

New Method ◽

Test Vehicle ◽

Vehicle Performance ◽

Key Technologies

Aiming at the shortcoming of test system used in our country and fulfilling the practical need of the enterprise, this paper advances a new method to test vehicle performance based on virtual instruments, studies and builds a new vehicle performance test system based on virtual instrument technique. This paper develops and applies a series of new critical technologies about signal processing. The test proves that the system offers high accuracy and reliability by use of these key technologies and realizes the fully compatible in connection of sensor and second instrument.

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Voltage Flicker Detecting Based on Improved HHT

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001711010038 ◽

2017 ◽

Vol 11 (1) ◽

pp. 38-47

Author(s):

Xiyu Xu ◽

Zhenmei Li ◽

Rui Ma ◽

Haitao Li ◽

Fuwei Zhang

Keyword(s):

Virtual Instrument ◽

Wavelet Denoising ◽

New Method ◽

Hilbert Huang Transform ◽

Mode Decomposition ◽

Feature Information ◽

Higher Harmonic ◽

Envelope Signal ◽

Voltage Flicker ◽

Harmonic Components

This paper puts forward a new method based on Hilbert-Huang Transform (HHT) and Wavelet denoising for extracting feature information of voltage flicker signal. Firstly, envelope signal could be extracted by using HHT from original signal containing noises. Then the noises and higher harmonic components of envelope signal could be removed by using Wavelet denoising. Finally, the noise-removing envelope signal could be decomposed by using Empirical Mode Decomposition (EMD) for getting accurate amplitude modulation wave. The new method was applied to virtual instrument by using the MATLAB script node in LabVIEW. Experimental results show that this new method is applicable for analyzing voltage flicker signal both in time domain and frequency domain. The accurate time, amplitude and frequency of voltage flicker signal which is mutational and non-stationary can be obtained by using this new method.

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Selective Sampling and Orientation of Non-Homogeneous Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100238 ◽

1968 ◽

Vol 26 ◽

pp. 98-99

Author(s):

C. C. Clawson ◽

L. W. Anderson ◽

R. A. Good

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Light Microscopy ◽

Random Sampling ◽

New Method ◽

Microscope Examination ◽

Small Areas ◽

Selective Sampling ◽

Large Numbers ◽

Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

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