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Summary

In this video, the speaker walks through the process of modifying a Simio model for a driver's license office. The modification introduces a computerized exam kiosk, replacing one of the two human exam clerks. The changes are made by adjusting server capacities, creating new paths, and running simulations to verify the outcomes. The video also explores adding a failure sync for applicants who fail the exam and adjusting the failure rate using selection weights. Results show that the model performs as expected, with applicants being split evenly between the human and computer exams, and a clear distinction between those who pass and fail.

Takeaways

• 😀 The video focuses on modifications to a driver's license exam simulation model, incorporating a computerized exam kiosk as an optional choice for applicants.
• 😀 A human exam clerk is replaced by the computerized kiosk, which can handle two exam takers simultaneously.
• 😀 Initially, the system assumes a 50/50 split in applicant choice between the human clerk and the computerized kiosk.
• 😀 The capacity of the human exam station was reduced from 2 to 1 to accommodate the new computerized exam option.
• 😀 A new server object was created for the computerized exam, maintaining the same processing time characteristics as the human exam clerk.
• 😀 The simulation model was updated by connecting the check-in process to both the human and computerized exam paths using multiplace functionality.
• 😀 The model uses default random routing with equal selection weights (1 each) to decide whether an applicant goes to the human exam or the computerized kiosk.
• 😀 Verification of the model was done by running the simulation in Fast Forward mode, comparing the results with expected utilization and performance for both exam paths.
• 😀 Results showed that the human exam's utilization remained almost unchanged while the computerized exam utilization was about half of the human exam's.
• 😀 A failure path was introduced to track applicants who fail the exam, and the simulation was updated to account for both pass and fail outcomes.
• 😀 Failure percentages were adjusted by modifying selection weights for both the pass and fail paths, allowing control over the failure rate (e.g., 10% failure and 90% pass).

Q & A

What modification is being made to the driver's license bureau's exam process?

The modification involves adding an optional computerized exam kiosk, which replaces one of the two human exam clerks. This kiosk supports two exam takers at a time, and it is assumed that half of the applicants will choose the kiosk while the other half will choose the human clerk.

How does the Simio model handle the choice between the human exam and the computer exam kiosk?

Simio handles the choice randomly by assigning a selection weight to each path. By default, the selection weight for both paths (human exam and computer exam) is set to 1, so Simio will distribute the applicants equally, with half going to the human exam and half to the computer exam.

What changes are made to the human exam in the Simio model?

The human exam is renamed to 'human exam,' and its capacity is reduced from 2 to 1, reflecting the replacement of one human clerk by the computerized exam kiosk.

What are the characteristics of the computer exam in the Simio model?

The computer exam is created as a new server object with a capacity of 2. The processing time is the same as that of the human exam, with an exponentially distributed processing time of 8.8 minutes per exam.

How does the verification process work in the Simio model?

The verification process involves running the model in fast-forward mode and checking the pivot grid to see if the results align with the expected values. The expected outcomes are that the human exam should have a similar utilization rate to the original model, and the computer exam should have approximately half the utilization due to the reduced arrival rate.

What changes are expected in the results after implementing the modification in the model?

The human exam’s utilization should remain roughly the same as in the previous model since its processing time hasn’t changed, though its arrival rate is halved. The computer exam, with two units of capacity and half the arrival rate, should have a utilization about half of the human exam’s.

How can failure rates be incorporated into the Simio model?

Failure rates can be incorporated by adding a 'fail' sync object and connecting both the human and computer exam processes to it. The failure rate can be adjusted by changing the selection weights for the 'fail' and 'pass' paths, with the sum of the weights determining the distribution of applicants between the two outcomes.

What is the expected outcome when 10% of applicants fail the exam in the Simio model?

If 10% of applicants fail the exam, the selection weight for the failure path would be set to 10, and the selection weight for the pass path would be set to 90. This results in approximately 10% of applicants being routed to the 'fail' sync and 90% passing, which is reflected in the simulation results.

How does Simio distribute applicants between the 'pass' and 'fail' paths?

Simio uses the selection weight of each path to determine the distribution of applicants. If the selection weight for the 'fail' path is set to 10 and the 'pass' path to 90, Simio will route 10% of applicants to the 'fail' path and 90% to the 'pass' path based on the weighted probabilities.

What is the purpose of the pivot grid in the Simio model?

The pivot grid is used to analyze the simulation results by showing key performance metrics, such as time in system for different entities. It helps validate if the model is behaving as expected and provides insights into the performance of the human and computer exam processes.