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Resources and Containers

Standard SimPy objects are static. Dynamic DES introduces dynamic wrapper classes that subscribe directly to the Registry to update their capacity, consumption, or contents in real time.

1. Discrete Resources (DynamicResource)

DynamicResource wraps a SimPy Resource and represents discrete assets that process individual tasks (e.g. machines, bays, or operators).

Shrinking Safety Guarantee

When capacity increases, tokens are immediately added to the pool. When capacity shrinks (e.g., from 5 to 2 due to an unexpected machine breakdown): * If 4 machines are currently processing tasks, Dynamic DES will not terminate active processes. * The resource enters a temporary "over-capacity" state where it waits for tasks to finish. * As tasks complete and release their tokens, DynamicResource intercepts and discards them until the capacity level naturally drops to the targeted limit (2).

2. Continuous Containers (DynamicContainer)

DynamicContainer wraps a SimPy Container and represents continuous quantities (e.g. fuel tank levels, conveyor queues, or concept drift/physical wear).

Continuous states are updated dynamically via: * Level: The current fluid level or quantity of material. * Capacity: The physical size limit of the tank/container.

3. Dynamic Stores (DynamicStore)

DynamicStore wraps a SimPy FilterStore and represents item-based collections with filtering capabilities (e.g. warehouses, buffer areas, or order books).

# Declare resources and containers in SimulationContext
app = (
    SimulationContext(sim_id="Line_A")
    .add_resource("lathe", current_cap=2, max_cap=5)
    .add_container("fuel_tank", current_cap=100.0, max_cap=500.0)
)