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Figure 4.3: Network Representation of Objects and its Attributes in AgentPower
4.3.2 Virtual World
After identifying the objects, the next step is to create a virtual world. In the virtual world, resource and demand agents, and their virtual relations, are specified. There are
two objects defined in the above section. One will be assigned as a demand agent and the other as a resource agent. The demand agent represents a task or work to be done.
The resource agent represents someone or something that can fulfil the task. In this system, object duty is the demand agent whilst object crew is the 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. Figure 4.3 shows the virtual world where the demand and
resource agents are specified.
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Figure 4.4: Demand Agent and Resource Agent in Virtual World
After specifying the demand and resource agents, the next step is to specify the virtual relationship between them. The purpose of the virtual relationship is to set criteria of
matching between the demand agent and resource agent. In this system, we want to reschedule duty to other crews because the crew is late or unavailable. To reschedule
the duty, there are rules that need to be followed as presented in Section 4.2. In short, the matching criteria in virtual relationships should be based on the reassignment rules.
In AgentPower, there are two types of relationships that need to be defined: matching condition and decision-making machine DMM. Matching condition determines the
matching criterion for demand agent and resource agent. When there are several matches for an agent, then the DMM condition determines the best from them. Figure
4.4 illustrates the screen shot where the matching conditions are set in the virtual world.
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Figure 4.5: Matching Conditions in Virtual World
There are different virtual relationships defined in the system according to the type of events and rescheduling rules as mentioned in Section 4.2. Three groups of events are
specified: first, LFSO, and DFSO; second, LFR, LFSW, and DFSW; and third, UNV. Below are the details of the matching conditions and DMM conditions for every group
specified above.
a LFSO and DFSO
Matching conditions
Condition 1: Crew Resource.SignOn = Duty Demand.MinimumRequired Time Condition 2: Crew Resource.StartTime1 = Duty Demand.LateCrewReadyTime
The first condition specifies that the crew agent CA must sign-on sign-on before or at the time specified minimum required time by the duty agent DA. The second
condition is that the starting time of the first work start time 1 of CA must be later or equal to the late-crew ready time late crew ready time. If both conditions are satisfied,
there is a match between demand agent DA and resource agent CA.
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DMM Condition
Condition 1: Crew Resource.SignOn Order: Max descending Weight: 100
The condition indicates that the CA with the latest sign-on time Sign On will be the best match.
b LFR, LFSW and DFSW
Matching Conditions
Condition 1: Crew Resource.CrewReadyTime = Duty Demand.StartTime Condition 2: Crew Resource.StartTime2 = Duty Demand.LateCrewReadyTime
The first condition signifies that CA ready time crew ready time, in this case referring to time after sufficient relief, must be equal or less than the starting time start time of
the DA. The second condition implies that CA starting time for the second work start time 2 should be equal or later than the late-crew ready time late crew ready time. If
both conditions are fulfilled there is a match between DA and CA. DMM Condition
Condition 1: Crew Resource.StartTime2 Order: Min ascending Weight: 100
The condition designates the CA with the earliest time of start work 2 to be selected.
c UNV
Matching Conditions
Condition 1: Crew Resource.HoursAvailable = Duty Demand.HoursRequired Condition 2: Crew Resource.FinishTime2 = Duty Demand.StartTime
Condition 3: Crew Resource.SignOff = Duty Demand.StartTime
The first condition specifies that the CA’s driving hours available hours available in that day should be equal to or more than the driving hours required hours required by
the DA. Condition 2 indicates the CA finish time 2 should be equal to or less than the
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start time required by the DA. Condition 3 signifies that the CA sign off time should be equal to or later than the start time required by the DA. If all conditions are fulfilled,
then there is a match between the CA and DA. DMM Condition
Condition 1:Crew Resource.HoursAvailable Order:Maxdescending Weight: 100
Condition 1 shows that the CA with the highest hours available will be the best match.
4.3.3 The Matching Simulation