Experimental research on vibration damping for flat airplane panels

The article provides a detailed analysis of the influence of the combination of performance indicators of mobile lifts with working platforms (MLWP) at the stage of stopping and the process of vibration damping after stopping the working platform. On the basis of the results of experimental research and processing of the obtained data, an analysis was made of the influence of the angles of inclination of the upper and lower sections of the boom and the mass of the load in the working platform on the maximum amplitude of oscillations of accelerations when the working platform is locked, the period of oscillations and the time of their damping. As a result of the analysis, the spectrum of the response surfaces of the maximum amplitude of acceleration oscillations when the working platform is locked, the period of oscillations and the time of their damping from the working mass and the angles of inclination of the lower and upper boom sections was obtained, on the basis of which it can be concluded that the value of the maximum amplitude of acceleration oscillations in the locking time of the working platform is most influenced by the mass of the load in the working platform.

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An Experimental Research on the Vibration of Surface-Textured Journal Bearings

Shock and Vibration ◽

10.1155/2017/1261826 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Jian Dong ◽

Xiaojing Wang ◽

Jin Zhang ◽

Xiaoqing Xiang ◽

Zhou Nie ◽

...

Keyword(s):

Wear Resistance ◽

Experimental Research ◽

Load Capacity ◽

Journal Bearings ◽

Vibration Damping ◽

Damping Effect ◽

Acceleration Amplitude ◽

Bearing Vibration ◽

Partial Distribution ◽

Microfabrication Techniques

Growing attention has been paid to surface texture owing to its significance in bearing lubrication, load capacity, and wear resistance. In this paper, research emphasis is placed on the influence of texture distributions on bearing vibration and rotor stability. With microfabrication techniques, three kinds of textures configurations (0–90° partial distribution, 0–160° partial distribution, and 0–160° full distribution) are designed and applied on the lower pad surface. The experiment of journal bearings is carried out. The experiment results show that there is a significant decrease in acceleration amplitude of the textured bearings compared to nontextured bearings. Furthermore, the 0–160° partially distributed journal bearings have better vibration damping effect than another two kinds of textures, which can be verified by the shaft center orbits, Fourier spectrums, and waterfall plots.

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Simulation and Experimental Research of the Grinder'S Wheelhead Dynamics

Journal of Vibration and Control ◽

10.1177/1077546304041369 ◽

2004 ◽

Vol 10 (6) ◽

pp. 915-930 ◽

Cited By ~ 4

Author(s):

Franciszek Oryński ◽

Witold Pawłowski

Keyword(s):

Physical Model ◽

Experimental Research ◽

Forced Vibration ◽

Vibration Damping ◽

Grinding Wheel ◽

Grinding Process ◽

Hydrostatic Bearings ◽

Simulation Based

In this paper we present a simulation based on the physical model of a cylindrical, plunge grinder with hydrostatic slideways and hydrostatic bearings of a grinding wheel spindle. The simulation was carried out in order to check the influence of the grinding process on the forced vibration damping of the wheelhead. The experimental research was undertaken to verify the idea of the damping facility of the grinding process. The results of the experiments and the simulation were used to draw the final conclusions.

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Secondary Transfer Effect of Contact

Social Psychology ◽

10.1027/1864-9335.40.2.55 ◽

2009 ◽

Vol 40 (2) ◽

pp. 55-65 ◽

Cited By ~ 146

Author(s):

Thomas F. Pettigrew

Keyword(s):

Cognitive Dissonance ◽

Experimental Research ◽

Intergroup Contact ◽

Transfer Effect ◽

Evaluative Conditioning ◽

Transfer Effects ◽

Secondary Transfer ◽

Primary Reduction

This paper reviews the evidence for a secondary transfer effect of intergroup contact. Following a contact’s typical primary reduction in prejudice toward the outgroup involved in the contact, this effect involves a further, secondary reduction in prejudice toward noninvolved outgroups. Employing longitudinal German probability samples, we found that significant secondary transfer effects of intergroup contact exist, but they were limited to specific outgroups that are similar to the contacted outgroup in perceived stereotypes, status or stigma. Since the contact-prejudice link is bidirectional, the effect is inflated when prior prejudice reducing contact is not controlled. The strongest evidence derives from experimental research. Both cognitive (dissonance) and affective (evaluative conditioning) explanations for the effect are offered.

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