Multiobjective Optimization for Train Speed Trajectory in CTCS High-Speed Railway With Hybrid Evolutionary Algorithm

In this paper, the dynamic amplification factors (DAFs) of high-speed railway continuous girder bridges are studied. The vehicle-bridge interactions (VBIs) of 13 concrete continuous girder bridges with spans ranging from 48 to 130 m are analyzed, the influences of the train speed, the train marshalling and the bridge fundamental frequency on the DAF are investigated, and the DAF design standard for high-speed railway bridges is discussed. The results indicate that for the continuous beam bridge whose fundamental frequency is less than 3.0 Hz, the maximum DAF is no more than 1.15; while for the bridge examples with a fundamental frequency larger than 3.0 Hz, the maximum DAF reaches 1.25 because the resonance occurs at high train speed. The empirical formulas of the DAFs in the Japan Railway Technical Research Institute (JRTRI) code could provide a conservative estimation of the DAFs of high-speed railway continuous bridges.

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Notch-based speed trajectory optimisation for high-speed railway automatic train operation

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/09544097211042184 ◽

2021 ◽

pp. 095440972110421

Author(s):

Minling Feng ◽

Chaoxian Wu ◽

Shaofeng Lu ◽

Yihui Wang

Keyword(s):

High Speed ◽

Applied Force ◽

Mixed Integer ◽

High Speed Railway ◽

Train Operation ◽

Train Speed ◽

Automatic Train Operation ◽

The Impact ◽

Trajectory Optimisation

Automatic train operation (ATO) systems are fast becoming one of the key components of the intelligent high-speed railway (HSR). Designing an effective optimal speed trajectory for ATO is critical to guide the high-speed train (HST) to operate with high service quality in a more energy-efficient way. In many advanced HSR systems, the traction/braking systems would provide multiple notches to satisfy the traction/braking demands. This paper modelled the applied force as a controlled variable based on the selection of notch to realise a notch-based train speed trajectory optimisation model to be solved by mixed integer linear programming (MILP). A notch selection model with flexible vertical relaxation was proposed to allow the traction/braking efforts to change dynamically along with the selected notch by introducing a series of binary variables. Two case studies were proposed in this paper where Case study 1 was conducted to investigate the impact of the dynamic notch selection on train operations, and the optimal result indicates that the applied force can be flexibly adjusted corresponding to different notches following a similar operation sequence determined by optimal train control theory. Moreover, in addition to the maximum traction/braking notches and coasting, medium notches with appropriate vertical relaxation would be applied in accordance with the specific traction/braking demands to make the model feasible. In Case study 2, a comprehensive numerical example with the parameters of CRH380AL HST demonstrates the robustness of the model to deal with the varying speed limit and gradient in a real-world scenario. The notch-based model is able to obtain a more realistic optimal strategy containing dynamic notch selection and speed trajectory with an increase (1.622%) in energy consumption by comparing the results of the proposed model and the non-notch model.

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Improvement and Lock Calculation of Electric Switch Machine of Railway Turnout

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.409-410.1496 ◽

2013 ◽

Vol 409-410 ◽

pp. 1496-1501 ◽

Cited By ~ 1

Author(s):

Jing Mang Xu ◽

Ping Wang ◽

Hao Xu

Keyword(s):

Dynamic Model ◽

High Speed ◽

Lateral Stiffness ◽

High Speed Railway ◽

Train Speed ◽

Working Status ◽

Stress And Deformation ◽

Railway Turnout

Electric switch machine locks the crossing rail in the working direction and checks the working status of the crossing. With the increase of train speed, the ZD(J)9 electric switch machine cant satisfy the equipment of high speed railway, This paper studied the optimization; in order to study the lock calculation of nose rail after conversion, a dynamic model is established to research the influence of working status of the crossing. It indicates that for the first traction point, the stress and deformation are mainly affected by scant displacement between nose rail and wing rail; for the second traction point, they are affected by the gap between nose rail and spacer; fastener lateral stiffness doesnt influence the stress status, but the lateral fastener stiffness should not be too small.

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A Dimensional Diversity Based Hybrid Multiobjective Evolutionary Algorithm for Optimization Problem

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001416590205 ◽

2016 ◽

Vol 30 (07) ◽

pp. 1659020 ◽

Cited By ~ 1

Author(s):

Peng Wang ◽

Changsheng Zhang ◽

Bin Zhang ◽

Tingting Liu ◽

Jiaxuan Wu

Keyword(s):

Multiobjective Optimization ◽

Evolutionary Algorithm ◽

Optimization Problem ◽

Optimization Problems ◽

State Of The Art ◽

Experimental Results ◽

Selection Scheme ◽

Genetic Operator ◽

Hybrid Evolutionary Algorithm ◽

Multiobjective Optimization Problems

Multiobjective density driven evolutionary algorithm (MODdEA) has been quite successful in solving multiobjective optimization problems (MOPs). To further improve its performance and address its deficiencies, this paper proposes a hybrid evolutionary algorithm based on dimensional diversity (DD) and firework explosion (FE). DD is defined to reflect the diversity degree of population dimension. Based on DD, a selection scheme is designed to balance diversity and convergence. A hybrid variation based on FE and genetic operator is designed to facilitate diversity of population. The proposed algorithm is tested on 14 tests problems with diverse characteristics and compared with three state-of-the-art designs. Experimental results show that the proposed design is better or at par with the chosen state-of-the-art algorithms for multiobjective optimization.

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Alternative methodologies to the semi-analitic solution to the problem of moving loads on high speed railway bridges based on the sensitivity of the response to train speed and on hilbert transformation

10.30827/digibug.31231 ◽

2014 ◽

Author(s):

Enrique García Macías

Keyword(s):

High Speed ◽

Hilbert Transformation ◽

Moving Loads ◽

High Speed Railway ◽

Railway Bridges ◽

Train Speed

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High-speed train speed estimation via one geophone near an high-speed railway

10.1190/segam2021-3594545.1 ◽

2021 ◽

Author(s):

Xiaokai Wang ◽

Baoli Wang ◽

Chun Li ◽

Wenchao Chen ◽

Chen Zhao

Keyword(s):

High Speed ◽

Speed Estimation ◽

High Speed Train ◽

High Speed Railway ◽

Train Speed

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Ship Hull Structural Multiobjective Optimization by Evolutionary Algorithm

Journal of Ship Research ◽

10.5957/jsr.2014.58.2.45 ◽

2014 ◽

Vol 58 (02) ◽

pp. 45-69 ◽

Cited By ~ 1

Author(s):

Zbigniew Sekulski

Keyword(s):

Multiobjective Optimization ◽

Evolutionary Algorithm ◽

High Speed ◽

Computational Models ◽

Plate Thickness ◽

Structural Elements ◽

Structural Members ◽

Design Variables ◽

Longitudinal Stiffeners ◽

Further Development

An evolutionary algorithm for multiobjective optimization of the structural elements of the large spatial sections of ships is presented. The evolutionary algorithm where selection takes place based on the aggregated objective function combined with domination attributes as well as distance to the asymptotic solution is proposed and applied to solve the problem of optimizing structural elements with respect to their weight and surface area on a high-speed vehicle-passenger catamaran structure with several design variables such as plate thickness, scantlings of longitudinal stiffeners and transverse frames, and spacing between longitudinal and transversal structural members. Details of the computational models were at the level typical for conceptual design. Scantlings were analyzed using the selected rules of a classification society. The results of numerical experiments with the use of the developed algorithm are presented. They show that the proposed genetic algorithm can be a foundation of the effective multiobjective optimization tool for ship structure optimization. Further development of the tool should include more advanced methods for ship structural analysis.

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