Introduction

SIMCEL enables users to create interconnected plans to simulate their supply chain over different periods. Each plan's output informs the next, ensuring continuity. Additionally, the backend process of initializing new plans from the existing list is crucial for maintaining this seamless chain.

This documentation covers the rules and processes for plan creation, initialization, and continuity.

Key Concepts

Actual Data: Historical supply chain data such as inventory, sales, and production output.

Primary Scenarios: Each plan includes one primary scenario, which determines the plan's output. In reality, the implementation of the plan is based on this scenario.

Plan Dependencies: Dependencies between plans are inferred from their start times; a plan depends on the latest prior plan.

Future Plans: Any plan with a start date larger than the actual plan end date.

Forecast Base: A statistical demand projection based on historical sales, excluding past demand events that influenced those sales. It serves as the preliminary input for the planning exercise in SIMCEL.

Plan Initialization

Plan Initialization in SIMCEL is a back-end procedure that ensures the system handles the creation of new plans accurately. Here are the key steps involved when a plan is created:

Run the Forecaster

Use the selected forecasting method to generate Sales Out (sales from primary to secondary customers) forecasts.

Update Forecast Base

SIMCEL will check the primary scenario (PS) of the previous plan (the dependent plan). Depending on the presence of events in the PS:

No Events Applied: If no events were applied to the PS, the forecast result from the forecaster will become the Forecast Base of the new plan without any adjustments.

Events Found: If any events were applied in the previous plan’s PS, all of these events will be used to shape the forecaster result. This adjusted forecast will then become the Forecast Base of the new plan.

Plan Continuity

Plan continuity in SIMCEL ensures that each planning period connects smoothly to the next. Here are the key points:

Data Source for Plan Connection

Connecting with Actual Data: If the selected plan connects with actual data, it uses this actual data as the reference for parameters.

Connecting without Actual Data: If the plan does not connect with actual data, it uses the primary scenario from the preceding plans. In SIMCEL, this subset of data is called "Update Current."

Ending Stock Initialization

The ending stock from the selected reference data (determined in the previous step) is used as the initial inventory for the new plan.

How it works

SIMCEL operates by running simulations in daily steps, starting from an initial dataset and progressing one day at a time.

Example

Context:

Actual Data: October 2021 to December 31, 2023

Future Plans:

Quarter 1 - 2024 (Plan 1): January 1, 2024, to December 2025

Quarter 2 - 2024 (Plan 2): April 1, 2024, to March 2026

Simulation Implementation:

Quarter 1 - 2024:

As the first plan, it uses actual data from October 2021 to December 31, 2023, to generate input for the entire period.

Within Quarter 1 - 2024, multiple scenarios can be created, but only one scenario is selected as the primary scenario.

Quarter 2 - 2024:

This plan depends on the Quarter 1 - 2024 plan. Because the actual data for January to March 2024 is missing, the Quarter 2 plan uses the primary scenario forecast from the Quarter 1 plan for this period (Update Current). This means the initial inventory for Quarter 2 is based on the end-month inventory level of March 30, 2024, from the primary scenario of the Quarter 1 plan.

When users update the actual data for January to March 2024, the Quarter 2 plan will use the updated actual data directly for the inventory initialization, rather than the forecast from the Quarter 1 plan.