Distribution Path Optimization for Intelligent Logistics Vehicles of Urban Rail Transportation Using VRP Optimization Model

The main difference between locomotive schedule of heavy haul railways and that of regular rail transportation is the number of locomotives utilized for one train. One heavy-loaded train usually has more than one locomotive, but a regular train only has one. This paper develops an optimization model for the multilocomotive scheduling problem (MLSP) through analyzing the current locomotive schedule of Da-qin Railway. The objective function of our paper is to minimize the total number of utilized locomotives. The MLSP is nondeterministic polynomial (NP) hard. Therefore, we convert the multilocomotive traction problem into a single-locomotive traction problem. Then, the single-locomotive traction problem (SLTP) can be converted into an assignment problem. The Hungarian algorithm is applied to solve the model and obtain the optimal locomotive schedule. We use the variance of detention time of locomotives at stations to evaluate the stability of locomotive schedule. In order to evaluate the effectiveness of the proposed optimization model, case studies for 20 kt and 30 kt heavy-loaded combined trains on Da-qin Railway are both conducted. Compared to the current schedules, the optimal schedules from the proposed models can save 62 and 47 locomotives for 20 kt and 30 kt heavy-loaded combined trains, respectively. Therefore, the effectiveness of the proposed model and its solution algorithm are both valid.

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Empirical Analysis on the Risk Factors of Total Repurchase Price in BT Project of Urban Rail Transit

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.357-360.2890 ◽

2013 ◽

Vol 357-360 ◽

pp. 2890-2895

Author(s):

Li Ming Xia ◽

Le Sun

Keyword(s):

Risk Factors ◽

Cluster Analysis ◽

Empirical Analysis ◽

Urban Rail Transit ◽

Rail Transit ◽

Rail Transportation ◽

Factors Affecting ◽

Urban Rail

Through the identification of the risk factors affecting the total repurchase price in BT project of the urban rail transit, we obtain data by questionnaires and make cluster analysis on all risk variables.Then select the key risk factors that affect total repurchase price,which play a guiding role for controlling the total repurchase price in the BT project of urban rail transportation.

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Passenger Boarding/Alighting Management in Urban Rail Transportation

2012 Joint Rail Conference ◽

10.1115/jrc2012-74102 ◽

2012 ◽

Cited By ~ 2

Author(s):

Sonia Baee ◽

Farshad Eshghi ◽

S. Mehdi Hashemi ◽

Rayehe Moienfar

Keyword(s):

Travel Time ◽

System Performance ◽

Heavy Traffic ◽

System Capacity ◽

Rapid Decline ◽

Rail Transportation ◽

Satisfaction Level ◽

Urban Rail ◽

Subway System ◽

Measures Of Performance

Heavy traffic consequences in crowded cities can be extremely reduced by using mass transportation. Recent extensive studies on Tehran subway system, as a representative of crowded cities, show that ever increasing commutation demand results in rapid decline in service quality and satisfaction level, system capacity wastage, and poorer system performance. Since passenger boarding/alighting period is noticeable compared to the inter-station travel time, it seems that passenger boarding/alighting management would play a significant role in system performance improvement. Aiming at increasing satisfaction level and service success rate, while reducing travel time, different boarding/alighting strategies are proposed. Passengers behaviors are carefully simulated based on a microscopic model, through introducing an inclination function which governs a passengers movement in a two-dimensional queue. Simulation results, in terms of three aforementioned measures of performance, show that in less crowded stations, the first strategy, expectedly, outperforms the other two. However, in crowded stations (e.g. interchange stations) the third strategy outperforms the others significantly.

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