117 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| #!/usr/bin/env python
 | |
| 
 | |
| from datetime import datetime, timedelta
 | |
| import numpy as np
 | |
| import random
 | |
| import sys
 | |
| import pytz
 | |
| 
 | |
| from aman.sys.aco.Ant import Ant
 | |
| from aman.sys.aco.Configuration import Configuration
 | |
| from aman.sys.aco.RunwayManager import RunwayManager
 | |
| from aman.types.Inbound import Inbound
 | |
| 
 | |
| # This class implements the ant colony of the following paper:
 | |
| # https://sci-hub.mksa.top/10.1109/cec.2019.8790135
 | |
| class Colony:
 | |
|     def associateInbound(rwyManager : RunwayManager, inbound : Inbound, earliestArrivalTime : datetime, useITA : bool):
 | |
|         rwy, eta, _ = rwyManager.selectArrivalRunway(inbound, useITA, earliestArrivalTime)
 | |
|         eta = max(earliestArrivalTime, eta)
 | |
| 
 | |
|         inbound.PlannedRunway = rwy
 | |
|         inbound.PlannedStar = inbound.ArrivalCandidates[rwy.Name].Star
 | |
|         inbound.PlannedArrivalTime = eta
 | |
|         inbound.InitialArrivalTime = inbound.ArrivalCandidates[rwy.Name].InitialArrivalTime
 | |
|         rwyManager.RunwayInbounds[rwy.Name] = inbound
 | |
| 
 | |
|     def calculateInitialCosts(rwyManager : RunwayManager, inbounds, earliestArrivalTime : datetime):
 | |
|         overallDelay = timedelta(seconds = 0)
 | |
| 
 | |
|         # assume that the inbounds are sorted in FCFS order
 | |
|         print('FCFS-Sequence:')
 | |
|         tmp = datetime.now().replace(tzinfo = pytz.UTC) + timedelta(seconds = 50 * len(inbounds))
 | |
|         for inbound in inbounds:
 | |
|             for runway in inbound.ArrivalCandidates:
 | |
|                 inbound.ArrivalCandidates[runway].InitialArrivalTime = tmp
 | |
|                 inbound.ArrivalCandidates[runway].EarliestArrivalTime = tmp
 | |
|             tmp += timedelta(seconds = 20)
 | |
|             Colony.associateInbound(rwyManager, inbound, earliestArrivalTime, False)
 | |
|             overallDelay += inbound.PlannedArrivalTime - inbound.InitialArrivalTime
 | |
|             print('    ' + inbound.Report.aircraft.callsign + ': ' + inbound.PlannedRunway.Name + ' @ ' + str(inbound.PlannedArrivalTime) +
 | |
|                   ' dt=' + str((inbound.PlannedArrivalTime - inbound.InitialArrivalTime).total_seconds()))
 | |
| 
 | |
|         return overallDelay
 | |
| 
 | |
|     def __init__(self, configuration : Configuration):
 | |
|         self.Configuration = configuration
 | |
|         self.ResultDelay = None
 | |
|         self.Result = None
 | |
| 
 | |
|         rwyManager = RunwayManager(self.Configuration)
 | |
|         delay = Colony.calculateInitialCosts(rwyManager, self.Configuration.Inbounds, self.Configuration.EarliestArrivalTime)
 | |
|         self.FcfsDelay = delay
 | |
| 
 | |
|         # check if FCFS is the ideal solution
 | |
|         if 0.0 >= delay.total_seconds():
 | |
|             self.Result = self.Configuration.Inbounds
 | |
|             self.ResultDelay = delay
 | |
|             return 
 | |
| 
 | |
|         # initial value for the optimization
 | |
|         self.Configuration.ThetaZero = 1.0 / (len(self.Configuration.Inbounds) * (delay.total_seconds() / 60.0))
 | |
|         self.PheromoneMatrix = np.ones(( len(self.Configuration.Inbounds), len(self.Configuration.Inbounds) ), dtype=float) * self.Configuration.ThetaZero
 | |
| 
 | |
|     def optimize(self):
 | |
|         # FCFS is the best solution
 | |
|         if None != self.Result:
 | |
|             return
 | |
| 
 | |
|         # define the tracking variables
 | |
|         bestSequence = None
 | |
| 
 | |
|         # run the optimization loops
 | |
|         for _ in range(0, self.Configuration.ExplorationRuns):
 | |
|             # select the first inbound
 | |
|             index = random.randint(1, len(self.Configuration.Inbounds)) - 1
 | |
|             candidates = []
 | |
| 
 | |
|             for _ in range(0, self.Configuration.AntCount):
 | |
|                 # let the ant find a solution
 | |
|                 ant = Ant(self.PheromoneMatrix, self.Configuration)
 | |
|                 ant.findSolution(index)
 | |
| 
 | |
|                 # fallback to check if findSolution was successful
 | |
|                 if None == ant.SequenceDelay or None == ant.Sequence:
 | |
|                     sys.stderr.write('Invalid ANT run detected!')
 | |
|                     sys.exit(-1)
 | |
| 
 | |
|                 candidates.append([ ant.SequenceDelay, ant.Sequence ])
 | |
| 
 | |
|             # find the best solution in all candidates of this generation
 | |
|             bestCandidate = None
 | |
|             for candidate in candidates:
 | |
|                 if None == bestCandidate or candidate[0] < bestCandidate[0]:
 | |
|                     bestCandidate = candidate
 | |
| 
 | |
|                 dTheta = 1.0 / (candidate[0].total_seconds() / 60.0)
 | |
|                 for i in range(1, len(candidate[1])):
 | |
|                     update = (1.0 - self.Configuration.Epsilon) * self.PheromoneMatrix[candidate[1][i - 1], candidate[1][i]] + dTheta
 | |
|                     self.PheromoneMatrix[candidate[1][i - 1], candidate[1][i]] = max(update, self.Configuration.ThetaZero)
 | |
| 
 | |
|             # check if we find a new best candidate
 | |
|             if None != bestCandidate:
 | |
|                 if None == bestSequence or bestCandidate[0] < bestSequence[0]:
 | |
|                     bestSequence = bestCandidate
 | |
| 
 | |
|         # create the final sequence
 | |
|         if None != bestSequence:
 | |
|             # create the resulting sequence
 | |
|             self.ResultDelay = bestSequence[0]
 | |
|             self.Result = []
 | |
| 
 | |
|             # finalize the sequence
 | |
|             rwyManager = RunwayManager(self.Configuration)
 | |
|             for i in range(0, len(bestSequence[1])):
 | |
|                 self.Result.append(self.Configuration.Inbounds[bestSequence[1][i]])
 | |
|                 Colony.associateInbound(rwyManager, self.Result[-1], self.Configuration.EarliestArrivalTime, True)
 |