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exceed four and half hours, and total daily driving time should not exceed ten. The relief time should be at least forty-five minutes. Crew rescheduling is based on the
manual rescheduling that is currently practised by bus companies in London. In the next sections, we will explain the details of CRSMAS based on the MAS concept.
3.4 Modelling with
MAS
This section presents the detailed model of CRSMAS. It presents the CRSMAS architecture, agent types and MAS interactions.
3.4.1 CRSMAS Architecture
Figure 3.6 illustrates the MAS architecture for the CRSMAS. The architecture is based on the autonomous agent architecture where an agent is not controlled or managed by
any other agent or human being Jennings et al., 1998; Ferber,1999; Shen et al., 2001.
In the CRSMAS we identify two agents that are Crew Agent CA and Duty Agent DA. We define our agents as cognitive agents. Cognitive agents possess an internal
representation model of the world and expertise, have goals and plans, are capable of reasoning, and can cooperate, coordinate, negotiate, and communicate with other agents
Nwana, 1996; Jennings et al., 1998; Wooldridge, 2002. CA represents a crew, and DA corresponds to a duty that needs to find a crew because the original crew is late, or
unavailable. There is a virtual world where agents interact, communicate and negotiate. In this
virtual world, there are resource and demand agents. A demand agent represents a task or work to be done. A resource agent represents someone or something that can fulfil
the task. In this system, DA is the demand agent whilst CA is resource agent. This is due to the fact that the duty is a task that needs to be done while the crew is the resource
able to fulfil the task.
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CREWS DUTIES
CA 1 DA 1
CA 3 CA 2
CA ..N
DA 2
DA 3
DA ..N Resource Agents
Demand Agents
Virtual World
Figure 3.6: Architecture for CRSMAS
3.4.2 Agents Type
There are two types of agent presented in the system architecture: crew agent and duty agent. Every agent has their own objective, responsibility and attributes as presented
below: a Crew Agent CA
CA represents a crew that works for a bus company. Their objectives are to get a salary
and to work in a safe and healthy environment. Their main responsibility is to drive a bus according to a prescribed schedule. A crew has five activities SignOn, Drive,
Relief, SignOff, and StandBy. SignOn is the time for a crew to start a duty, Drive is when a crew drives a bus, Relief is when a crew takes a break, SignOff is when a crew
finishes hisher duty on a day, and StandBy is when the state of a crew is in stand by mode. A crew has permission to read crew schedules, duty assignment, and their crew
details. A crew is not allowed to drive continuously for more than 4.5 hours, must at least take a relief equal or more than 45 minutes, and total driving hours in a day should
be equal to or less than 10 hours in a day. Table 3.1 shows the attributes for CA.
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b Duty Agent DA A DA corresponds to a duty that results in the loss of its driver because of UE such as
lateness, delay, or unavailable. A DA’s objective is to find a driver that will drive the duty. A DA’s responsibility is to make sure that a crew takes the duty. Table 3.2
illustrates the attributes for a DA.
Table 3.1: The Attributes for CA
Name Description
Crew ID Identification number for a crew
Route Number The route number that was assigned to the crew
Duty Number The duty number that was assigned to the crew
Sign-On Time The time the crew should sign-on at garage.
Start Work 1 Time The starting time for the crew first piece of work.
Finish Work 1 Time The finishing time for the crew first piece of work.
Start Break Time The starting time for the break.
Finish Break Time The finishing time for the break.
Start Work 2 Time The starting time for the crew second piece of work.
Finish Work 2 Time The finishing time for the crew second piece of work.
Sign-Off Time The sign-off time for the crew at garage.
Status To indicate the status of a crew for the purpose of
rescheduling, 0 if not available and 1 if available.
Table 3.2: The Attributes for DA
Name Description
Route No Number for the route
Duty No Number of the duty
Start Time The start time for the duty to be covered.
End Time The end time for the duty to be covered
Total Time Total time that need to be covered
Minimum Required Time A minimum required time to cover the duty. Late Crew Ready Time
The time when the late-crew is ready.
3.4.2 Agents Interaction
