scholarly journals Determination of Necessary Subsidiary Track According to Train Operation Frequency in a Heterogeneous Train Pattern

2020 ◽  
Vol 10 (12) ◽  
pp. 4164
Author(s):  
Hyoung June Kim

In this study, a genetic algorithm was used to calculate the scheduled waiting time according to the train operation frequency of heterogeneous trains operating on one track. The acquired data were then used to determine the appropriate subsidiary track at which high-speed trains can load or release cargo away from low-speed trains. A metaheuristic genetic algorithm was applied and implemented using Javascript/jQuery. Six cases were investigated, which provided values of subsidiary track that vary according to the operation frequencies of different types of trains, and solutions were derived through 100 simulations using a stochastic method. The analysis results showed that the train overtaking frequency was the highest at the third intermediate station within the simulation, suggesting that this particular station requires a subsidiary track, even if the operating frequency of each train differs across the entire track considered in this study. The results of this study are expected to facilitate objective and practical planning during railway construction.

2020 ◽  
Vol 10 (12) ◽  
pp. 4226
Author(s):  
Tanita Fossli Brustad ◽  
Rune Dalmo

Track geometry is a fundamental subject in railway construction. With the demand for increased capacity in terms of load and speed, the need for suitable transitions between consecutive track sections is highly relevant. Properly constructed transition curves lead to improved travel comfort, increased safety, and reduced wear. The well known clothoid curve is widely used as a transition curve; however, the linear curvature is not sufficiently smooth to meet the requirements for railways carrying high speed trains or heavy hauls. Blending spline curves are flexible spline constructions possessing favourable smoothness properties at the end points, which makes them considerable for use as transition curves. This paper demonstrates some selected blending splines applied as transition curves between two existing circular arc segments selected from the Ofotbanen railway. The main results in this paper are related to the smoothness at the end points and the behaviour of the curvature of the curves, where the new transition curves were shown to be smoother than the original clothoid. Another new result is the observation that the proposed method allows for the improvement of existing railways without forcing extensive changes to the original track. Some representative examples are included to highlight the flexibility of this first instance of blending splines as transition curves.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Wenchuan Cai ◽  
Wenhao Liao ◽  
Danyong Li ◽  
Yongduan Song

Train traction/braking control, one of the key enabling technologies for automatic train operation, literally takes its action through adhesion force. However, adhesion coefficient of high speed train (HST) is uncertain in general because it varies with wheel-rail surface condition and running speed; thus, it is extremely difficult to be measured, which makes traction/braking control design and implementation of HSTs greatly challenging. In this work, force observers are applied to estimate the adhesion force or/and the resistance, based on which simple traction/braking control schemes are established under the consideration of actual wheel-rail adhesion condition. It is shown that the proposed controllers have simple structure and can be easily implemented from real applications. Numerical simulation also validates the effectiveness of the proposed control scheme.


Author(s):  
Jeong-Rae Cho ◽  
Kilje Jung ◽  
Keunhee Cho ◽  
Jong-Won Kwark ◽  
Young Jin Kim ◽  
...  

Georesursy ◽  
2021 ◽  
Vol 23 (2) ◽  
pp. 132-141
Author(s):  
Maria M. Fomina ◽  
Natalia S. Balushkina ◽  
Oleg V. Khotylev ◽  
Anton G. Kalmykov ◽  
Georgy A. Kalmykov ◽  
...  

The article presents the results of the Tutleim formation complex studies of core from 16 wells drilled on an area of 900 km2 near the Kamennaya crest of the Krasnoleninsky arch. The area is characterized by the variability of the structural plan, preserved from the time of deposits sedimentation, that might affect the structure of formation. Regionally traceable lithological units were used to describe different types of sections, which were firmly recorded on the core and on the logs. The article presents the results of the sections correlation, that shows the variability of the Tutleim formation through the area, identifies typical sections for the submerged, slope and crestal parts of the investigated field. The section may contain two reservoir intervals of different types: radiolarite and siliceous-phosphate layers with average porosity values of 7% and 15%, respectively. The radiolarite layers form the main potential-productive intervals, that are found in all types of sections on one or two stratigraphic levels: in the crestal sections only in the third unit, in the slope and submerged sections – in the first, second and third units. The phosphorite layer in the fifth unit is a characteristic singularity only of the crestal sections. The obtained results allow predicting the distribution of the potential-productive intervals of the Tutleim formation and its stratigraphic analogues in different areas with higher accuracy.


2014 ◽  
Vol 505-506 ◽  
pp. 619-623
Author(s):  
Hao Jia ◽  
Bao Ming Han ◽  
Qi Zhang

Considering the demand of night train on Beijing-Guangzhou high-speed railway, two modes of segmented rectangular maintenance time window are discussed. Methods to make train operation plans under these two modes are proposed, aiming at shortening the train waiting time and making the departure and arrival time more reasonable. Comparing the new designed train operation plans with the original one under the vertical rectangular maintenance time window, it shows that segmented rectangular maintenance time window is better in night train operation.


2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Zhao-heng Zhang ◽  
Jian-ming Ding ◽  
Jian-hui Lin

A wheelset bearing is a crucial energy transmission element in high-speed trains. Any parts of the wheelset bearing that have faults may endanger the safety of the railway service. Therefore, it is important to monitor the running condition of a wheelset bearing. The multifault on a wheelset bearing is very common, and these impulsive components generated by different types of faults may interact with each other, which increases the difficulty of entirely identifying those faults. To solve the multifault problem, this paper proposed a hierarchical shift-invariant K-means singular value decomposition (H-SI-K-SVD) to hierarchically separate those multifault impulsive components based on their fault power levels. Each of the separated impulse signals contains only one fault impulse, and the fault information could be highlighted both in time domain and frequency domain. In addition, the sparsity of envelope spectrum (SES) is introduced as an indicator to adaptively tune a key parameter in this method. The effectiveness of the proposed method is verified by both simulation and experimental signals. Compared with ensemble empirical model decomposition (EEMD), the proposed method exhibits better performance in separating the multifault impulsive components and detecting the faults of a wheelset bearing.


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