Discrete Event Simulation Project Proposal Class:DSES Simulation Modeling And Analysis Name:Kevin Lewelling Date:February 17, 2002 To:Professor Ernesto Butierrez-Miravete Background: Over the past year, the Super Stop & Shop store on the corner of Skiff St. and Dixwell Ave. in Hamden, CT has installed two new self-service systems. The first system was installed in the deli department and allows shoppers to place orders using an interactive touch screen computer system. The second self-service system allows shoppers to self check-out. Two systems have been implemented for the self-service check-out system. The earliest system targetted shoppers with 20 items or less. This system was configured with four check-out stations with a single customer service representative located in a central location as shown in Figure 1. Following what appeared to be a successful trial period, Stop & Shop imstalled a new self-service check-out system shown in Figure 2 which was re-oriented to the traditional isle type configuration. The new system not only has two isles designated for shoppers with 12 items or less but also has three new isles that can accommodate as many groceries as you care to scan. For the new system, S&S has hired two customer service associates that circulate between the check-out isles to aid shoppers in their check-out process. None of the check-out systems have employees dedicated to bagging groceries Problem Statement: Stop & Shop grocery stores have implemented the use of self-service check-out lines to reduce operating costs. This is accomplished by eliminating both a cashier and a food packaging associate in each check-out isle. Removing the cashier, who is typically located in part of the isle, allows the new self-service check-out systemsto be narrower and therefore require less floor space. Although the self-service lines may move a bit slower due to shoppers being unfamiliar with the system and inevitable hangups, total shopper throughput may be increased simply by adding more check-out lines, hense allowing for better utilization of the check-out area of the store. Stop & Shop wants to know if they should install more self-service check-out lines such that shopper through put is maximia\zed based on the floor space available. The focus of this study will be to determine the optimum number of self-service lines required to maximize shopper throughput based on check-out area floor space available. Approach: An initial visit will be made to the Stop & Shop super market to accurately document the configuration of each check-out line. A Pro-Model simulation model will then be created based on the configuration schematic. A separate visit will be made to collect arrival times and processing times for each check-out line configuration. This will include data from both of the full service check-out lines, 12 items or less and the unlimited lines, as well as data from both self-service check- out lines, again 12 items or less and the unlimited lines. Roughly 1 hour of data will be collected for each check-out line for a total of 4 hours worth of data. Data will be collected on a weekend to ensure minimal idle times in each of the check-out lines. A simulation will be run to baseline the current configuration to determine the current maximum customer throughput. An optimization routine will then be run, varying the number of individual check-out line configurations, to determine the optimum full and self-service check-out line combination.

Figure 1 - Stage I Self-Service Check-Out System ScanPayBag Pay & Bag Scan Pay & Bag Scan Pay & Bag Scan Waiting Area for Shoppers Ready for Check-Out Station 3Station 4 Customer Service Desk Station 1Station 2 Arrivals To Processing at Customer Service Desk Exit Pay & Bag Scan PayBagScanPayBagScanPayBag 12 Items or Less No Limit Waiting Area for Shoppers Ready for Check-Out Figure 2 - Stage II Self-Service Check-Out System