scholarly journals Mathematical model of the formation and development of wave-shaped rail wear when an electric locomotive operates in the traction mode in tangent sections of the track

2019 ◽  
Vol 78 (3) ◽  
pp. 131-140
Author(s):  
A. Ya. Kogan

The problem of wave-shaped rail wear is highly relevant for rail transport. The paper presents a mathematical model of the formation and development of wave-shaped rail wear. The task of estimating vertical wear of the rail head under the axles of electric locomotives passing in the traction mode is considered. A technique has been developed that allows building chain of calculations that determine the formation and development of a wave-shaped rail head wear. A specific calculation example is given, illustrating the process of propagation of a wave-shaped wear from the source of its formation in the direction of train motion. An example of the calculation allows drawing the following conclusions:1. Wave-shaped wear primarily occurs when the shock interaction of the wheel of an electric locomotive moving in the traction mode and a rail thread having imperfections of the rolling surface. Such imperfections, among others, may be a joint with a significant gap or a “step down” in the direction of the locomotive, as well as a welded joint with defect 46.3-4.2. Wavelength of the wave-shaped rail wear, its configuration and amplitude of the fundamental tone are determined mainly by joint oscillations of the wheel-motor unit of the locomotive and the track infrastructure in the field of high-frequency oscillations (120 – 180 Hz).3. Multivariate calculations showed that in steady state, the distribution speed of wave-shaped rail wear in the direction of train motion (as a function of the number of axles of electric locomotives passed in traction mode) is directly proportional to the vertical load at the wheel and rail contact in the slip zone 0≤Q≤F/(2nψk), is inversely proportional to wear resistance C and significantly depends on the parameters of the undercarriage of the electric train and the track superstructure.

Epilepsia ◽  
2021 ◽  
Author(s):  
Nicole E. C. Klink ◽  
Willemiek J. E. M. Zweiphenning ◽  
Cyrille H. Ferrier ◽  
Peter H. Gosselaar ◽  
Kai J. Miller ◽  
...  

Author(s):  
Lotte Noorlag ◽  
Maryse A. van 't Klooster ◽  
Alexander C. van Huffelen ◽  
Nicole E.C. van Klink ◽  
Manon J.N.L. Benders ◽  
...  

2017 ◽  
Vol 130 ◽  
pp. 21-26 ◽  
Author(s):  
Laura Uva ◽  
Davide Boido ◽  
Massimo Avoli ◽  
Marco de Curtis ◽  
Maxime Lévesque

1989 ◽  
Vol 63 (7) ◽  
pp. 44S-46S ◽  
Author(s):  
L. FREITAG ◽  
J. BREMME ◽  
M. SCHROER

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Musa Ozturk ◽  
Ashwin Viswanathan ◽  
Sameer A. Sheth ◽  
Nuri F. Ince

AbstractDespite having remarkable utility in treating movement disorders, the lack of understanding of the underlying mechanisms of high-frequency deep brain stimulation (DBS) is a main challenge in choosing personalized stimulation parameters. Here we investigate the modulations in local field potentials induced by electrical stimulation of the subthalamic nucleus (STN) at therapeutic and non-therapeutic frequencies in Parkinson’s disease patients undergoing DBS surgery. We find that therapeutic high-frequency stimulation (130–180 Hz) induces high-frequency oscillations (~300 Hz, HFO) similar to those observed with pharmacological treatment. Along with HFOs, we also observed evoked compound activity (ECA) after each stimulation pulse. While ECA was observed in both therapeutic and non-therapeutic (20 Hz) stimulation, the HFOs were induced only with therapeutic frequencies, and the associated ECA were significantly more resonant. The relative degree of enhancement in the HFO power was related to the interaction of stimulation pulse with the phase of ECA. We propose that high-frequency STN-DBS tunes the neural oscillations to their healthy/treated state, similar to pharmacological treatment, and the stimulation frequency to maximize these oscillations can be inferred from the phase of ECA waveforms of individual subjects. The induced HFOs can, therefore, be utilized as a marker of successful re-calibration of the dysfunctional circuit generating PD symptoms.


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