Results 231 to 240 of about 14,988 (268)

Study of Time-Frequency Order Tracking of Vibration Signals of Rotating Machinery in Changing State

2008 International Symposiums on Information Processing, 2008
Order tracking is an important method for condition monitoring and fault diagnosis, dynamic analysis and design in rotating machinery. Especially, the hidden fault is usually easier to discover at engine run up/down. Order tracking is implemented by band pass filter in time-frequency domain and time signal of desired order is reconstructed. Compared to
Xiaoping Zhao, Qingpeng Kong, Qingtao Guo   +2 more
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Sensibility to Changes of Vibrational Modes of Excited Electron: Sum Frequency Signals Versus Difference Frequency Signals

Communications in Theoretical Physics, 2011
In this paper, we investigate a two electronic level system with vibrational modes coupled to a Brownian oscillator bath. The difference frequency generation (DFG) signals and sum frequency generation (SFG) signals are calculated. It is shown that, for the same model, the SFG signals are more sensitive than the DFG signals to the changes of the ...
An-Na Gu, Xian-Ting Liang
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Effect of a Change in Position of a Support on the Natural Frequencies and Modes of Vibration of a System

Journal of Mechanical Engineering Science, 1965
The effect of a small change in position of one of the supports on the natural frequencies and modes of a structure, which is ‘continuous’ over a number of supports, is examined in this paper. Using energy and receptance methods a simple formula is obtained for the change in natural frequency of a beam when the support displacement is infinitesimal ...
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Frequency shift or intensity shift? The origin of spectral changes in vibrational spectra

Vibrational Spectroscopy, 2012
Abstract It has been shown that the frequency shift for a single band can be reconstructed by a linear combination of contributions from adjacent bands with fixed positions. Assuming discrete distribution of the peaks in a specified spectral range and an appropriate response function one can generate diverse patterns of spectral changes.
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Vaporization energy change and vibrational frequency shift in substituted mono-halo-benzenes

Theoretica Chimica Acta, 1970
Direct linear relation exists between the reduced vaporization energy change (ΔHv/RTB) of benzene and its homologues, C6H5X (X=F, Cl, Br, I) and the X-sensitive dimensionless frequency (hcv/kTB) at their respective normal boiling point (TB) temperatures.
J. Lielmezs, J. B. Butler, H. C. Henry, R. G. Orr   +3 more
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The change of the vibrational frequencies of a chemisorbed diatomic caused by the electrostatic interactions with the metal surface

Surface Science, 1981
Abstract Results of density functional calculations are used to discuss the change of the vibrational frequency of an adsorbed molecule caused by the electrostatic interaction between a chemisorbed molecule — simulated by two effective charges — and a metallic surface.
Shlomo Efrima, Horia Metiu
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[Changes of vibration frequency due to root resorption of deciduous tooth].

Shoni shikagaku zasshi. The Japanese journal of pedodontics, 1992
The purpose of this study was to investigate the changes of vibration frequency of a deciduous tooth due to physiological root resorption. The author developed an analysis system for tooth vibration by applying an impact-hammer to the tooth. Peak frequency (Hz) of the tooth stimulated by the impact-hammer was observed by the analysis system.
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Relation between Thermodynamic Property Change and Vibrational Frequency Shift in Ethyl Halides

Nature, 1966
RELATIONS can be found by plotting the difference of the ideal gas state thermodynamic properties ΔS° and ΔCp°; formed between the thermodynamic property values of ethane, C2H6, and its homologues, C2H5X (X = F, Cl, Br, I), against the corresponding C–X bond stretching and C–C–X bond bending frequencies in ethyl halide series (Fig. 1).
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[Pathomorphological and histochemical changes in the intestines of white rats due to low-frequency vibration].

Eksperimentalna meditsina i morfologiia, 1977
The authors carried out experiments on animals (40 white male rats) which were subjected to daily a two-hour action of the common vertical sinusoidal vibrations with a frequency of 20 Hr (I group) and 50 Hr (II group) with acceleration of 22,0 m/sec2 for a period of ten days (I group--A and second group--A) and 30 days (I group--B and II group--B ...
M, Zlateva, D, Mashnova
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Vasomotor changes in human skin elicited by high frequency low amplitude vibration

Acta Physiologica Scandinavica, 1985
C R, Skoglund, E, Knutsson
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