Usability testing of smart inventory software for EOQ, ROP and SS with recommendation decision in the context of SMEs

The advent of technology urges the competitive competition in economy. Many entrepreneurs endeavor to generate many strategies to obtain efficient production and cost they spent. One of the factors contributing to operational cost is the management inventories. The circulation of raw material in inventories require to be managed to assure that the supply of company's inventory by neither hoarding lots of products nor running out of products. Supporting the strategy to manage the inventory, the development of information system to obtain the calculation to determine when the company to purchase the material, how much the minimum material required to be stored and how much the company requires to purchase in each reservation. The software system is developed particularly to provide an advice to Small Medium Enterprises (SMEs) which still have many drawbacks such as skill to follow technology. The software development focused on providing information pertaining to Economic Order Quantity (EOQ), Reorder Point (ROP) and Safety Stock (SS) to manager of SMEs, namely Smart Inventory Software (SIS). The software is designed as Decision Support System (DSS) in which the output supports the manager to take decision of each material stored in the inventories. SIS also provides recommendation to summary the condition of each material managed in the inventories. The experiment design is arranged to measure the usability of SIS by analyzing six tasks during the experiment which are 1). opening application, 2). filling the property of stock such material name, unit, storage cost, and others 3). the monthly demand of stock in annual period from January to December 4). the evaluation command to calculate EOQ, ROP and SS, 5). operating the edit function of to amend the property of stock and 6). the delete command evaluation for selected data. By evaluating the software through performing six tasks, the corresponding parameters such Error Rate, Completion Time and Usability Factor was collected. The result yields that the SUS score for SIS Software is 69 which means the software is categorized as OK and can be applied to assist their works, while the average error rate software from the user for all tasks is 1%. The longest tasks to accomplish are task 2 and 3 where the user should input data material for the cost and sold material each month respectively