## 1 Introduction  
Car manufacturers have been attempting to reduce costs and cycle time and increase efficiency by adopting innovative approaches such as make and deliver to order, zero-error-production, lean manufacturing, and just-in-time (JIT) production to survive global competition [1]. One of the recent trends in automobile assembly is to simplify the assembly process by adopting the modularization of parts. Modularization is a production method in which a parts supplier manufactures automobile parts in large units and supplies them to original equipment manufacturers (OEM's). Modularization has a cost-saving effect since the load and production stages of the OEM are reduced because the tasks performed by an OEM, such as design, production, assembly, inspection, and sales, are divided among module production companies. Furthermore, the expertise of parts manufacturers and the proportion of benefits created by them increase.  
Meanwhile, against the background of increasingly diverse consumer demands, the manufacturing process in the automobile industry has undergone changes to suit mass customization. That is, the number of automobile models has increased, and consumers can choose various customizations for each model. To accommodate the diversification of specifications in the limited assembly lines, the modules and parts of planned specifications have to be fed into the automobile bodies that flow on the assembly line. In general, this work is called sequencing. The purpose of sequencing is to produce and supply the modules and parts according to specification in the exact order required. Today, about 40% of the parts supplied to automotive OEM's require sequencing [2], and if an error occurs in the sequencing, the assembly line must be stopped, otherwise serious problems such as resupplying or reassembling of the expensive module parts may occur. Therefore, a rigorous process to prevent sequencing errors is very important in the inbound logistics of automobiles.  
Thus far, the automobile industry has been using the barcode system to reduce the problems occurring in the supply chain or assembly process such as sequencing. By attaching shipping labels, the accuracy of part recognition and transportation has been increased, misrouting has been reduced, and the accuracy of the location of parts and work in progress has been improved [3]. However, since the barcode system used for preventing sequencing errors involves manual work, human errors can occur, and inefficiency may arise in cases such as when a worker has to manually bring the barcode reader to the location where the barcode tag is attached to check the sequence of individual parts present in containers such as trolleys and boxes.  
Radio Frequency Identification (RFID) can solve the problems and overcome the inefficiency of the barcode system. RFID does not require a line of sight and has the advantages that multiple identification is possible and more information can be stored [4]. RFID technology has already been used for various purposes in closed loop applications, and the automobile industry has made considerable investments in RFID technology every year to manage returnable transport items (RTI's) such as racks, totes, and pallets [5]. If RFID can be used to overcome the disadvantages of the barcode system, the object recognition speed may be improved; human errors can be prevented; and the accuracy of information flow and the efficiency of processes will be increased.  
With the above considerations, this study aims to develop an RFID infrastructure-based logistics monitoring and sequencing system for reducing sequencing error and sharing real-time inventory information. We implemented and evaluated the latest RFID technologies and standards (in particular, EPCglobal standards) for item-level RFID tracing and sequencing in a manufacturing environment. Furthermore, we analyzed the economic benefits of RFID from the improved inbound logistics visibility and prevented sequencing errors.