Thesis (M.Eng.)--Chulalongkorn University, 1999

In this study, a computer-based inventory management system application that can work with a bar-coding system for an automotive parts industry, TBK Krungthep Co., Ltd, has been developed. This application deals with material updating (updating stock status), material issuance activities, and inventory reports. A general description about the organization, including organization structures and general production processes has been delineated. First of all, the existing inventory system has been studied, using the data flow diagrams (DFD) in order to identify problematic areas, data, and information flow at first place. Then, additional system requirements determination has been surveyed. After that, a barcode system and codes for the warehouse have been set. Finally, a computer-based inventory management system and inventory database has been designed under a client/server environment. The system allows warehouse operator to input the data of the receiving and picking transactions, using a barcode scanner. Moreover, the system also provides real-time reports for supervisors or managers including summary of receiving, picking, EOQ and ABC analysis. The average amount of parts per year in the Economic Order Quantity (EOQ) and ABC analysis reports are estimated using the recorded picking amounts in the inventory database. In the implementation process, the new system is compared with the existing system in three areas, which are accuracy, timeliness, and overstocking, using a sampling set of selected parts. As a result, the errors in the database of the studied parts is decreased from 5% to 0%, while the timeliness of inputting data is improved from average 49.65 seconds to 25.85 seconds. Finally, the average on hand per day of type C items is reduced by more than 20% when using the EOQ model.