Berth Operation Simulation

# -*- coding: utf-8 -*-import sysimport codecsimport jsonimport randomimport simpy# Simulation Configurationclass CONFIGURATION(): # Defaults def __init__(self): self.params = { 'PT_MEAN': 50, # Service Average Time (Minutes) 'PT_SIGMA': 8, # Service Time Standard Deviation (Minutes) 'MTTF': 240, # Mean time to failure in minutes 'REPAIR_TEAM': 2, # Number of Repair Teams 'REPAIR_TIME': 30, # Repair Time (Minutes) 'SUPPORT_DURATION': 12, # Duration of Support Jobs (Minutes) 'NUM_BERTHS': 10, # Number of Berths 'WEEKS': 4 # Simulation Time (Weeks) } self.__derived__() # Derived Parameters def __derived__(self): # self.params['RANDOM_SEED'] = random.randint(20, 80) # Param. for expovariate distribution self.params['BREAK_MEAN'] = 1 / self.params['MTTF'] # Simulation time in minutes self.params['SIM_TIME'] = self.params['WEEKS'] * 7 * 24 * 60 # Read External Configuration File (JSON) def loadFromFile(self, sim_configFile): with codecs.open(sim_configFile, 'r', encoding='utf8') as jsonF: self.params = json.load(jsonF) self.__derived__() # Get Parameter Value by Name def getConfig(self, paramName): return self.params[paramName] # Define Ship Servicing Time def time_per_ship(self, vesselType=1): vesselTypeWeight = 1 / vesselType return random.normalvariate( vesselTypeWeight * self.params['PT_MEAN'], vesselTypeWeight * self.params['PT_SIGMA']) # Define Berth Survival Time def time_to_failure(self): return random.expovariate(self.params['BREAK_MEAN']) # Berth Operationclass Berth(object): # Instantiate def __init__(self, env, sim_config, name, repairTeam): self.env = env self.sim_config = sim_config self.name = name self.ships_served = {} self.berth_repaired = {} self.broken = False # Initiate Berth Operation Simulation self.process = env.process(self.servicing(repairTeam)) # Initiate Berth Repair Simulation self.env.process(self.break_berth()) # Service Ship Berth Operation def servicing(self, repairTeam): while True: # Dynamic Vessel Type vesselType = random.randint(1, self.sim_config.getConfig('VESSEL_TYPE')) # Ship Arrive to Berth done_in = self.sim_config.time_per_ship(vesselType) while done_in: try: # Service Start Time start = self.env.now yield self.env.timeout(done_in) done_in = 0 except simpy.Interrupt: self.broken = True # Calculate the Remaining Servicing Time done_in -= self.env.now - start # Request Berth Repair with High Priority with repairTeam.request(priority=1) as req: yield req # Wait for Repair Job Done yield self.env.timeout(self.sim_config.getConfig('REPAIR_TIME')) self.broken = False # Ship Completes Berth Operation if str(vesselType) in self.ships_served: self.ships_served[str(vesselType)] += 1 else: self.ships_served[str(vesselType)] = 1 # Berth Maintenance def break_berth(self): while True: # Awaiting Berth Broke _now_ = self.env.now # When Berth Broke if self.name in self.berth_repaired: self.berth_repaired[self.name].append(_now_) else: self.berth_repaired[self.name] = [_now_] yield self.env.timeout(self.sim_config.time_to_failure()) # Busy Berth if not self.broken: # Stop Berth Operation Servicing self.process.interrupt() # Ship Other Service Requestsdef support_jobs(env, sim_config, repairTeam): while True: # Ship Arrive to Berth done_in = sim_config.getConfig('SUPPORT_DURATION') while done_in: # Request Support Job with Low Priority with repairTeam.request(priority=2) as req: yield req try: # Support Job Start Time start = env.now yield env.timeout(done_in) done_in = 0 except simpy.Interrupt: # Calculate the Remaining Support Job Time done_in -= env.now - start # Berth Service/Repair Analysisdef service_statistics(sim_config, berths): print('Berth Operation: %s W (%d)' % ( sim_config.getConfig('WEEKS'), sim_config.getConfig('RANDOM_SEED'))) ship_type_served = {} for vesselType in range(sim_config.getConfig('VESSEL_TYPE')): ship_type_served[str(vesselType + 1)] = 0 # Berth Service Statistics for berth in berths: print('%s:' % (berth.name)) print(' Vessel Type:', end='\t') total_ship_served = 0 for vesselType in range(sim_config.getConfig('VESSEL_TYPE')): total_ship_served += berth.ships_served[str(vesselType + 1)] ship_type_served[str(vesselType + 1)] += berth.ships_served[str(vesselType + 1)] print('%6d' % (berth.ships_served[str(vesselType + 1)]), end='\t') print('%-6d' % total_ship_served) print(' Repair Time:') count = -1 for repair in berth.berth_repaired[berth.name]: print('\t\t%6d' % repair, end='\t') count += 1 if count % 3 == 2: print() print() # Vessel Type Served Statistics print('Vessel Type Statistics:', end='\t') ship_type_total_served = 0 for vesselType in range(sim_config.getConfig('VESSEL_TYPE')): ship_type_total_served += ship_type_served[str(vesselType + 1)] print('%6d' % (ship_type_served[str(vesselType + 1)]), end='\t') print('%6d' % ship_type_total_served) # Mainif __name__ == '__main__': # Configuration for Simulation sim_config = CONFIGURATION() # Giving Configuration File if len(sys.argv) > 0: sim_config.loadFromFile(sys.argv[1]) # Make the Result Changed Everytime random.seed(sim_config.getConfig('RANDOM_SEED')) # Simulation Initiation env = simpy.Environment() # Setup the Berth Repair Teams as Resource repairTeam = simpy.PreemptiveResource( env, capacity=sim_config.getConfig('REPAIR_TEAM')) # Setup the Berth Operation Consuming the Resource berths = [Berth(env, sim_config, 'Berth %d' % i, repairTeam) for i in range(sim_config.getConfig('NUM_BERTHS'))] # Setup the Berth Support Operation Consuming the Resource env.process(support_jobs(env, sim_config, repairTeam)) # Simulation Begin env.run(until=sim_config.getConfig('SIM_TIME')) # Berth Service/Repair Analyis service_statistics(sim_config, berths)