Formal Approach to Railway Applications - Formal Methods and Hybrid Real-Time Systems - page 506

rolling stock, regularly according to some rules, and which should be planned in
advance except for the operation of rolling stock itself. Therefore we also include
outside and inside cleaning of carriages, refueling diesel engines, refilling supplies
into restaurant carriages, water and oil refilling, etc.
In the [118] whole chapter 9 deals with this task. We also refer to [64] that
deals with application of genetic techniques to the planning of railway track
maintenance work. Fuzzy neural networks for machine maintenance in mass
transit railway systems are shown in [91].

2.7 Optimum Train Length

A determination of the train composition is another optimisation problem of
railway allocation and scheduling. It deals with the maximum usage of available
rolling-stock. The problem to be tackled is as follows: trains travel from station to
station. Trains are composed of carriages. At stations trains may have carriages
added (composed) to, or removed (decomposed) from the train. Station tracks
may restrict train additions and removals to occur only at either the front, or at
the back of a train. Given the requirements for trains to provide suitable load
(for example passenger) capacity along a journey with such demands varying,
the problem is now to plan that trains, during their journeys, have suitable
assemblies added to or removed from the train.
The costs of coupling and decoupling have to be taken into account. There
can be found graphical tools [38] that help dealing this task. We also refer to [52,
62, 78, 101].

2.8 Station Track Assignment

Track may be blocked for several trains. The planning and actual setting (i.e.
signalling) of the corresponding unit states is an essential function of station
management. Station management also involves determination of train positions.
Complexity issues of routing trains through railway stations can be found
in [87]. A case study of railway station management from the formal approach
is described in [50, 122].

2.9 Delay Train Management

In the everyday operation of a railroad, it is unfortunately not uncommon for
a train to arrive at a station with a delay. In such a situation, some of the
trains passengers may miss a connecting train, resulting in an even larger delay
for them since they have to wait for the next train. If, on the other hand, the
connecting train waits, then it is delayed itself, and so are all the passengers it is
carrying. Delay management consists of deciding which connecting trains should
wait for what delayed feeder trains, usually with the objective of minimizing the
overall discomfort faced by the passengers. Although railway optimization and
scheduling problems have been studied quite intensely over the past decade, the
management of delayed trains has received much less attention.
Scheduling and rescheduling of trains from the formal point of view can be
found in [20, 102].