Adjustment method for train disintegration and classification sequence in marshalling station

Adjustment of train disintegrating and classifying schemes in the marshalling station is the key of wagon-flow allocating optimization. The train disintegration and classification sequence is subjected to the priority of time departure. Under above-mentioned arrangement, the priority of time departure scheme is difficult to ensure the full-load of each departure train. On the basis of analyzing for interval time of departure train, waiting departure time and the relation among each time parameter, several concepts will be given. Using the method of single machine scheduling problem is to minimize the influence for classification and disintegration sequence adjustment. The necessary conditions of adjustment can be obtained and the influence after adjustment is shown by graphic deduction. Finally, the conception of time pass theory is provided. The rationality of this method has been proved by a case study. This method lays a foundation for adjustment of train classification and disintegration sequences.

how to guarantee full-load as far as possible and punctuality of departure time of each train.

Analysis of Operation Systems
Marshalling station is a technical station which includes different types of work. The operation procedure has the same characteristics with machine scheduling. On the basis of analyzing machine scheduling problem, the marshalling station can be divided into two subsystems, one is arrival disintegration subsystem and the other is classification departure subsystem, each subsystem includes three assembly lines. The assembly lines for how to work under horizontal and vertical model can be shown as Fig.1 .    ( 1) nn DB

Analysis of Initial Sequence
First, analyzing the time parameters at the condition of one shunting locomotive is under classification operation. If car flow follow is adequate, that is , car flow follow time is short, the trains will be depart compactly and the inspect operation of departure trains will be saturated. The waiting departure time n DCF T will appear as shown in Fig.2  In order to guarantee full-load and punctuality, n LSB t as an important parameter can get easily according to reference documentation [12] for follow-up adjustment: The latest classification starting time of other trains are closely linked with tightness degree. If , car flow follow is loose, the latest classification starting time will be got by inverse derivation: , the departure trains are compact classification, the latest classification starting time can be expressed as: Fig. 2(b), if the interval of latest classification starting time between adjoint trains can meet

Classification Sequence Adjustment between Adjacent Trains. As shown in
, it will be named compact continuing classification [12] . If each train can meet the compact continuing classification in periods, that can be defined as section compact continuing classification, that is  Figure 3. Adjustment scheme of classification sequence.
The parameter computation method after adjustment can be referenced to documentation [12]: After classification sequence adjustment, the largest adjustment for ' n LSB t is ) (

The Influence Analysis after
under this condition the train will not be delayed.

The condition of classification sequence adjustment. Only supported by following conditions the adjustment is effective:
Condition (1): In adjustment,  is defined to reflect virtues or defect degree of car flow. If  [13] , it will achieve the aim of full-load. The stepping trains classification sequence can be adjusted step by step [12] .

Analysis of Initial Sequence
Adjusting the disintegration sequence of arrival trains also can guarantee full-load. In order to guarantee the requirement of car flow in classification subsystem, the m EFJ t is an important parameter must be considered. When trains arrived on time, it can provide stable car flow, that is , as shown in Fig.4 (a). The arrival trains need a period of waiting time for disintegration, it can use T to indicate. The interval time will disappear when trains arrival frequently. At the same time, the disintegrate operation is compact in subsystem. As shown in Fig.4 (b), , car flow follow is loose, it will be got by extend calculation for time: , car flow is intensive, it will take follow track model:

Classification Sequence Adjustment between Adjacent Trains. Only meet the initial condition,
, it can adjust the disintegration sequence. The adjustment condition of disintegration sequence will be got by inverse derivation according to arrival time and technical operation time: The disintegration sequence adjustment scheme is as shown in Fig.5

The Influence Analysis after Adjustment.
After initial adjustment, in order to provide effective car flow for classification subsystem, it has to meet 0    Step2: For train No. 40 217, judging whether it meet condition (1).