CIS 666 Expert Systems
Assignment #0 Developing a Rule-Based System

Task:(I) Determining the gates to wich various flights must be routed in a large airport.

(a) Problem Definition:
The important factors affecting our system are the current status of the gates at the airport and the types of the flights. The system takes one flight and assign the best available gate for it with optimum increase of the airport traffic, and possibly put the flight in the waiting status. More specifically,
the type of gates and flights, the traffic on a specific gate, destination or direction of a flight, etc. are important factors for this task
The two natural feature classes of the problem are related with the gates and the flights as following;

GATES

Parameter  Possible values

Capacity   Small, Medium, Large
Traffic    Busy, OK
Type       International, Domestic
Direction  Incoming, Outgoing
Queue      0,1,2,..

FLIGHTS

Parameter       Possible Values

Origin          Airports in the world
Destination     Airports in the world
Aircraft Size   Small, Medium, Large

There may not be so many factors in our system, but their combination covers a lot of situation, e.g. if the gates are full arriving planes must turn on the air, or waiting for scheduling for an available time, doing every assignment into a systematic way for the convenience of the passengers, etc. On the other hand it does not make an explicit assignments for the later times, which can be added easily in the programming details.

(b) The major system components corresponding to the problem features and factors are as the following;

Fact Base:
   List of airports in the world, which have flight connection with this airport.
   List of tevery gate and its status
   Flights

Rule Base:

   Rules for the  flights and the gates in the fact base to produce new facts and delete old ones, i.e., assignments of the flights. Rules are arranged to cover all the possibilities of the flights and gates in the airport. 

Inference Engine;

   X engine take flights one by one from the fact base and make assignments to gates until it gets an empty ajanda.


(c) Rule Base:
1 IF Origin is not in USA
        Direction is Incoming AND Gate Type is International
2 IF Destination is not in USA
        Direction is Outgoing AND Gate Type is International
3 IF Origin is in US AND Destination is Airport
        Direction is Incoming AND Gate Type is Domestic
4 IF Origin is Airport and Destination is in US
        Direction is Outgoing AND Gate Type is Domestic
5 IF Aircraft Size is Large
        Capacity is Large
6 IF Aircraft Size is Medium
        Capacity is Medium
7 IF Aircraft Size is Small
        Capacity is Small
8 IF Direction is Incoming AND Gate Type is International
     AND Traffic is OK AND Queue is smaller than Gate Max
        Insert Gate as candidate, delete old candidate, decrease Gate Max 

9 IF Direction is Incoming AND Gate Type is Domestic
     AND Traffic is OK AND Queue is smaller than Gate Max
        Insert Gate as candidate, delete old candidate, decrease Gate Max 

10 IF Direction is Outgoing AND Gate Type is Domestic
     AND Traffic is OK AND Queue is smaller than Gate Max
        Insert Gate as candidate, delete old candidate, decrease Gate Max 

11 IF Direction is Outgoing AND Gate Type is International
     AND Traffic is OK AND Queue is smaller than Gate Max
        Insert Gate as candidate, delete old candidate, decrease Gate Max 

12 IF There is no more candidate 
        Insert candidate gate as the assigned gate AND set Gate Max to maximum value.