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Maximum absolute values of the car-body vertical acceleration.

Maximum absolute values of the car-body vertical acceleration.

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Railway tracks must be managed appropriately because their conditions significantly affect railway safety. Safety is ensured through inspections by track maintenance staff and maintenance based on measurements using dedicated track geometry cars. However, maintaining regional railway tracks using conventional methods is becoming difficult because o...

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... Similarly, Zhang et al. [29] extracted four features in the time domain and eight features in the frequency domain from carbody acceleration to estimate track irregularities. Tsunashima et al. [30,31] used the time − frequency analysis and Kalman filter to analyze the vertical acceleration of the carbody. They pointed out that this method can effectively evaluate the vertical track irregularity and should be employed in practice. ...
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... Some of the authors who use measurements from the train body attempt to estimate track geometry by using a dynamic model and different types of Kalman filters [18,26,[45][46][47][48][49]. Others extract signal features in time domain and in frequency domain and use them as TQI [25,[50][51][52] or to train ML models [22,28,30,53,54]. ...
... Thanks to this, they can adapt and model every interaction related to their management, and as a result, implement maintenance activities as part of the so-called "Data Driven Maintenance", i.e. maintenance based on data [58][59][60][61]. In the railway industry, such solutions are already being implemented -in the case of diagnostics of switch drives [62][63][64] and methods of monitoring the condition of tracks involving the installation of measuring devices, not on specialized rail cars, but on scheduled trains [65,66]. Only such models of real infrastructure objects can be treated as their digital twins, because they already have the ability to self-update. ...
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... 14 (8) 16 (9) 19 (11) 23 (15) 25 (17) 27 (19) 30 (22) Twist 23 (18) Target value of track irregurality correction for riding comfort Target value of track irregurality correction for safety +10 (+6) -5 (-4) 20 (14) 25 (19) 20 (14) < l a t e x i t s h a 1 _ b a s e 6 4 = " 3 E A x G d D K Y G H 4 k 8 U z v b 8 p z P l a z e A = " > A A A C b H i c h V G 7 S g N B F D 1 Z X z E + E h + F I M J i U K z C X R E V q 6 C N p U b j A x P C 7 j r G x X 2 ...
... Therefore, it is necessary to examine the effect of track conditions on the car body vibration. Tsunashima et al. developed a system to identify track faults using accelerometers and a GNSS placed on the car bodies of in-service vehicles [15,16]. Bai et al. used low cost accelerometers placed on or attached to the floors of operating trains to analyse track conditions [17]. ...
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... In 2023, Tsunashima et al. [69] developed a system for monitoring railway track conditions, which is crucial for ensuring safety. Traditional track maintenance on regional railways faces financial challenges and a lack of manpower. ...
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