Williams Bros. Appliances

Inventory and Point-of-Sale System

Interview Notes

January 30, 2017

When the owners need to acquire additional inventory, they refer to various manufacturers' catalogs and promotional materials, as well as industry reports and evaluations. They currently stock products from Whirlpool, GE, Kitchenaid, Maytag, Frigidaire, Tappan, Amana, Hotpoint, Roper, White Westinghouse, Sony, RCA, and Toshiba. If a customer prefers to special order a product, they can also accommodate them. Most special orders take 2-3 weeks to arrive.

For regular stock items, Ted or Will completes a two-part carbonless Purchase Order (see example in Figure 3) and mails or faxes it to the manufacturer's regional sales manager. After all the information has been entered, they calculate the extended price for each line item, and total the purchase order. The top copy is sent via mail or fax, and the second copy is filed in the "Ordered Inventory" folder.

When the ordered items arrive, Ted or Will pull the second copy of the Purchase Order out of the "Ordered Inventory" file and confirms that what they received was what they had ordered. If there are any items that are backordered (they ordered something but it didn't arrive with the rest of the shipment) they write a note on the purchase order, make a copy, and place this now third copy back in the "Ordered Inventory" folder. The second copy showing the items that were received is placed in the "Update New Inventory" folder.

Before the end of the day, Ted or Will goes through the "Update New Inventory" folder and records all products they received that day in a three-ring notebook--one notebook for each manufacturer (see example in Figure 4). When a product is sold and after it has been delivered, Ted or Will goes through the "Sales" folder, and for each product that was sold, selects the appropriate inventory notebook, matches the sold item with the listed item based on product number and serial number, and write down the date of the sale in the notebook. At the end of each week, one of the owners will also go through the "Sales" folder, and create a "Weekly Sales Report" of everything that was sold during the week. This report lists the product, manufacturer, product number, serial number, cost, and price. This report is then totaled to provide a record of weekly sales. Ted and Will would like to be able to see sales by product line, and by manufacturer, and would also like to create this report daily, but they just don't have the time.

a) Draw the state transition diagrams (STD) for the intended information system of the scenario?