MultiContainer + 2 ShiftAmounts

In certain scenarios it is important to distinguish which types of objects are available in a container. HasContainer does not provide this capability, while MultiContainer does.

A MultiContainer represents a named set of containers. The number of allowed containers is limited by parameter store_capacity.

For each container a name (id_ property), a capacity and level is specified.

A MultiContainer can be initialized with parameter initials as provided in the example for site and vessel configuration below.

In this example two ShiftAmountActivities are packed in a SequentialActivity, loading one piece of Cargo type 1 and one piece of Cargo type 2 from from_site to vessel01.

0. Import libraries

import datetime, time
import simpy

import shapely.geometry
import pandas as pd

import openclsim.core as core
import openclsim.model as model
import openclsim.plot as plot

1. Initialise simpy environment

# setup environment
simulation_start = 0
my_env = simpy.Environment(initial_time=simulation_start)

2. Define object classes

# create a Site object based on desired mixin classes
Site = type(
    "Site",
    (
        core.Identifiable,
        core.Log,
        core.Locatable,
        core.HasMultiContainer,
        core.HasResource,
    ),
    {},
)

# create a TransportProcessingResource object based on desired mixin classes
TransportProcessingResource = type(
    "TransportProcessingResource",
    (
        core.MultiContainerDependentMovable,
        core.Processor,
        core.HasResource,
        core.LoadingFunction,
        core.UnloadingFunction,
        core.Identifiable,
        core.Log,
    ),
    {},
)

3. Create objects

3.1. Create site object(s)

The clas HasContainer has now been replaced with HasMultiContainer. The from_site can contain four different container types, but right now contains only two: One called ‘Cargo type 1’ with a capacity of 10 and a level of 2 and one called ‘Cargo type 2’ with a capacity of 2 and a level of 0.

# prepare input data for from_site
location_from_site = shapely.geometry.Point(4.18055556, 52.18664444)
data_from_site = {"env": my_env,
                  "name": "from_site",
                  "geometry": location_from_site,
                  "store_capacity": 4,
                  "initials": [
                                  {"id": "Cargo type 1", "level": 10, "capacity": 10},
                                  {"id": "Cargo type 2", "level":  5, "capacity":  5},
                              ],
                 }
# instantiate from_site 
from_site = Site(**data_from_site)

3.2. Create vessel object(s)

The class ContainerDependentMovable has been replaced with MultiContainerDependentMovable. The vessel has two containers, one for ‘Cargo type 1’ and one for ‘Cargo type 2’, each with a capacity of two and a current level of zero.

# prepare input data for vessel_01
data_vessel01 = {"env": my_env,
                 "name": "vessel01",
                 "geometry": location_from_site, 
                 "loading_rate": 1,
                 "unloading_rate": 1,
                 "store_capacity": 4,
                 "initials": [
                                {"id": "Cargo type 1", "level": 0, "capacity": 2},
                                {"id": "Cargo type 2", "level": 0, "capacity": 2},
                             ],
                 "compute_v": lambda x: 10
               }
# instantiate vessel_01 
vessel01 = TransportProcessingResource(**data_vessel01)

ShiftAmount Activity for MultiContainer

The amount specifies the objects to be transfered and the id_ parameter specifies to which container this activity relates.

# initialise registry
registry = {}

# create a list of the sub processes and include reporting_activity
sub_processes = [
    model.ShiftAmountActivity(
        env=my_env,
        name="Transfer cargo type 1",
        registry=registry,
        processor=vessel01,
        origin=from_site,
        destination=vessel01,
        amount=1,
        id_="Cargo type 1",
        duration=20,
    ),
    model.ShiftAmountActivity(
        env=my_env,
        name="Transfer cargo type 2",
        registry=registry,
        processor=vessel01,
        origin=from_site,
        destination=vessel01,
        amount=1,
        id_="Cargo type 2",
        duration=40,
    )
]

# create a 'sequential activity' that is made up of the 'sub_processes'
sequential_activity = model.SequentialActivity(
    env=my_env,
    name="Sequential activity of basic activities",
    registry=registry,
    sub_processes=sub_processes,
)

4. Register processes and run simpy

# initate the simpy processes defined in the 'sub processes' and run simpy
model.register_processes(sequential_activity)
my_env.run()

5. Inspect results

5.1 Inspect logs

display(plot.get_log_dataframe(vessel01, [*sub_processes]))

	Activity	Timestamp	ActivityState	container level	geometry
0	Transfer cargo type 1	1970-01-01 00:00:00	START	{'Cargo type 1': 0, 'Cargo type 2': 0}	POINT (4.18055556 52.18664444)
1	Transfer cargo type 1	1970-01-01 00:00:20	STOP	{'Cargo type 2': 0, 'Cargo type 1': 1}	POINT (4.18055556 52.18664444)
2	Transfer cargo type 2	1970-01-01 00:00:20	START	{'Cargo type 2': 0, 'Cargo type 1': 1}	POINT (4.18055556 52.18664444)
3	Transfer cargo type 2	1970-01-01 00:01:00	STOP	{'Cargo type 1': 1, 'Cargo type 2': 1}	POINT (4.18055556 52.18664444)

display(plot.get_log_dataframe(from_site, [*sub_processes]))

	Activity	Timestamp	ActivityState	container level	geometry
0	Transfer cargo type 1	1970-01-01 00:00:00	START	{'Cargo type 1': 10, 'Cargo type 2': 5}	POINT (4.18055556 52.18664444)
1	Transfer cargo type 1	1970-01-01 00:00:20	STOP	{'Cargo type 2': 5, 'Cargo type 1': 9}	POINT (4.18055556 52.18664444)
2	Transfer cargo type 2	1970-01-01 00:00:20	START	{'Cargo type 2': 5, 'Cargo type 1': 9}	POINT (4.18055556 52.18664444)
3	Transfer cargo type 2	1970-01-01 00:01:00	STOP	{'Cargo type 1': 9, 'Cargo type 2': 4}	POINT (4.18055556 52.18664444)

5.2 Visualise gantt charts

plot.get_gantt_chart([sequential_activity, vessel01, *sub_processes])

5.3 Visualise step charts

fig = plot.get_step_chart([vessel01])

fig = plot.get_step_chart([from_site])

Observe that first 1 piece of ‘Cargo type 1’ is loaded from ‘from_site’ to ‘vessel01’. This takes 20 time units. Next 1 piece of ‘Cargo type 2’ is loaded from ‘from_site’ to ‘vessel01’. This takes 20 time units.

The original stock of ‘Cargo type 1’ was 10, and it is reduced to 9 after 20 time units. The original stock of ‘Cargo type 2’ was 5, and it is reduced to 4 after 60 time units.