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Ontology
Virtual World
Multi
-
Agent Engine
Software Interface Human Computer
Interface
Figure 4.2: AgentPower Architecture Source: Rzevski, 2002
There are several steps in developing a MAS in AgentPower. First, objects and their attributes in AgentPower an agent is called object are defined, then the supply and
demand agents and virtual relations between them in the virtual world are identified. Finally, the demands agents and resources agents are created, the attributes are filled in
and the simulation is run to experiment with the agents’ negotiations to find a match between them. The next subsections discuss the steps in detail.
4.3.1 Define Objects
In AgentPower, an agent is called an object in the ontology library but in the virtual world it is called an agent. Although the name is different, its purpose and function are
the same. Based on the proposed approach in Chapter Three Section 3.4.2, two types of agents are defined - crew agent and duty agent. In AgentPower, we implement crew
agent as crew object, and duty agent as duty object. Details of its attributes, description and data type are shown in Tables 4.8 crew and 4.9 duty. Almost all the attributes
are the same as presented in Section 3.4.2 but with a few additions. In object crew there a few attributes added: route no. 2, ready time, X, Y and self nexus. In object duty, the
additions are X, Y and self nexus. The additions are required because of requirements of
crew schedules, rescheduling rules and AgentPower. For example, AgentPower requires attributes X, Y and self nexus for the purpose of the matching process. Figure 4.2 shows
a screen shot from AgentPower that illustrates the visual representation of object crew and object duty and their attributes.
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Table 4.8: Attributes for Object Crew
Name Description Data
Type
Crew ID Identification number for a crew
String Route No. 1
The first route assigned to the crew String
Route No. 2 The second route assigned to the crew
String Duty Number
The duty number assigned to the crew Integer
Sign-on Time The time the crew should sign-on at garage.
Time Start Work 1 Time
The starting time for the crew’s first piece of work. Time
Finish Work 1 Time The finishing time for the crew’s first piece of work.
Time Start Relief Time
The starting time for the break. Time
Finish Relief Time The finishing time for the break.
Time Ready Time
Time calculated for the purpose of rescheduling 45 minutes after “Start Relief Time”.
Time Start Work 2 Time
The starting time for the crew’s second piece of work. Time
Finish Work 2 Time The finishing time for the crew’s second piece of work.
Time Sign-off Time
The sign-off time for the crew at garage. Time
Status To indicate the status of a crew for the purpose of
reassignment, 0 if not available and 1 if available. Integer
X Object position in the scene relative to X-direction
Integer Y
Object position in the scene relative to Y-direction Integer
Self Nexus A unique identifier of the project crew agent used for
agent identification in the scene Agent Reference
Table 4.9: Attributes for Object Duty
Name Description Data
Type
Route No Number for the route
String Duty No
Number of the duty Integer
Start Time The starting time for the duty to be covered.
Time Minimum Required Time
A minimum required time to cover the duty. Time
Late Crew Ready Time The time when the late-crew is ready.
Time X
Object position in the scene relative to X-direction Integer
Y Object position in the scene relative to Y-direction
Integer Self Nexus
A unique identifier of the project crew agent used for agent identification in the scene
Agent Reference
Abdul Samad Shibghatullah
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Figure 4.3: Network Representation of Objects and its Attributes in AgentPower
4.3.2 Virtual World
