Chankwon Park

Developing a shop floor scheduling and control software for an FMS

Abstract This paper is about the development of an operation software for a real FMS. The developed FMS software includes several modules: production planning module, shop floor scheduling module, operation control module, and manufacturing database module. These software modules, at shop floor level, are integrated with a plant management system, which acts as a test-bed to build a computer integrated manufacturing system (CIMS) in the future. This paper shows an imroved approach to the recently developed distributed scheduling and control scheme. To implement the scheme, a cell controller structure, protocols for scheduling and control and decision making procedures are designed. The scheme proposed in this paper is the second version of an operation software that was used to run the FMS. The revised software seems to work more efficiently and reliably, and the result of this study is currently used for operating the ASRI FMS installed in the Automation and Systems Research Institute (ASRI) at Seoul National University. To show the efficiency of the proposed scheme, a comparison study with other schemes is also included.

Performance analysis of alternative designs for a vehicle disassembly system using simulation modeling

Recently some regulations such as EPR (Extended Producer Responsibilities) have forced companies to develop an interest in recycling systems. In particular, these regulations are focused on the reuse of product materials to resolve environmental disruption or waste disposal. Unfortunately, a large amount of research has been conducted only in the field of mass production, rather than in the automotive disassembly systems that are more likely to have significant opportunities for reuse and recycling. Therefore, it has become necessary to conduct analytic research on systems with the capacity to deal with the annually increasing number of vehicles for disassembly. In this paper, we evaluate four existing vehicle disassembly systems and propose a new and improved alternative disassembly system. We also conduct performance analysis for each system using simulation modeling. Furthermore, we propose 4 alternatives and test their efficiencies in order to improve their performances.

Design of a Software Component Bank for Distribution

Recently, component-based software development technology is recognized as a new methodology that can overcome the problems of the traditional methodology at developing the software. It removes the problems by supporting fast development, easy maintenance, good quality, easy creation/upgrade of application, low cost, etc. It also creates new software business area such as business component developer, sales and distribution vendors. Many research institutes report that the market related with software component industry will grow with high rate. For the highly growing component market, a component distribution model is necessary to activate developing components, to promote the utilization, and to support distribution of them. In this paper, we propose a component distribution model through the requirement analysis. We also propose the UML model based on the requirement analysis, developed a prototype. We presented the developed system using several graphic user interfaces.

Efficient mapping rule of IDEF for UMM application

Various methodologies for business process analysis and design have been developed by many organizations. However, these methodologies are all uniquely developed to fit each organizations in their own ways and thuds are not compatible with each other. This poor compatibility between these methodologies incurs unnecessary analysis cost. In order to reduce this analysis cost, methods to map between the different methodologies need to be developed. UMM (UN/CEFACT Modeling Methodology) that has an object-oriented point of view can resolve the limits of the existing bottom-up approaches and make it more reasonable. It also simplifies the business and administrative procedures. IDEF (Integrated Definition Language) that has a structural point of view and is widely used as a system analysis and design method, needs to be mapped to UMM so that the existing IDEF models can be re-used. In this study, we present a guideline for procedures utilizing IDEF models from which the UMM models can be derived to develop an electronic commerce system that includes electronic documents exchange. By comparing IDEF and UMM, we analyze the differences between those two methodologies. Based on these differences, we propose basic strategies for mapping from IDEF to UMM. We also propose a mapping guideline which can be used to make suppositions of UMM results based on the modeling results of IDEF. The existing IDEF analysis/design results can be used to adopt UMM methodology for electronic business system. Therefore, with this, analysts who are familiar with the IDEF methodology can develop UMM work-flow by utilizing their existing results and skills.

Reorder decision system based on the concept of the order risk using neural networks

Due to the development of the modern information technology, many companies share the real-time inventory information. Thus the reorder decision using the shared information becomes a major issue in the supply chain operation. However, traditional reorder decision policies do not utilize the shared information effectively, resulting in the poor performance in distribution supply chains. Moreover, typical assumption in the traditional reorder decision systems that the demand pattern follows a specific probabilistic distribution function limits practical application to real situations where such probabilistic distribution function is not easily defined. Thus, we develop a reorder decision system based on the concept of the order risk using neural networks. We train the neural networks to learn the optimal reorder pattern that can be found by analyzing the historical data based on the concept of the order risk. Simulation results show that the proposed system gives superior performance to the traditional reorder policies. Additionally, managerial implication is provided regarding the environmental characteristics where the performance of the proposed system is maximized.

Development and Distribution of XML Standard Tax Invoices

The KEC XML Electronic Tax Invoice v3.0 which is a typical example of XML document was developed in 2009 according to the amendment of the Value Added Tax Law in 2008 that obliged all the corporation business to issue tax invoices electronically and submit them to the National Tax Service. The issue and submission of those tax invoices has been implemented since Jan. 2011 through a pilot test in 2010. It has some differences in aspect of standard, developing subject, technologies, and operation with the previous version of it. Above all, it is the first case of the XML document being developed based on international standard and methodologies and distributed nationally. This study aims to guide the future development of same kinds of standard XML document by arranging the development and distribution processes of XML Tax Invoice comprehensively.

A Weighted Load Balancing Heuristic that Minimizes Makespan in Alternative Routing and Machine Environment

Abstract Traditionally, the problems of manufacturing technology and manufacturing management have been treated independently. The process planning problem and the scheduling problem are a good example. In this research, we propose a scheduling system which solves the process planning problem and the scheduling problem simultaneously. We argue that we can obtain a better and practical scheduling solution by dynamically changing the processing machines and operations as the shop condition changes. The proposed scheduling system takes the initial process plan for alternative machines and operations represented by an AND/OR graph as its input. Other informational inputs to the system are part order and shop status. The system then generates new process plans and schedules iteratively, until we finally fix the process plan after verifying the performance of the schedules by a simulation study. Experimental results show that the proposed scheme provides a viable solution for real world scheduling problems.