• Journal of the Korea Society for Simulation
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• v.21 no.1
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• pp.55-68
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• 2012

Recently it is important to understand service supply chain because the economy moves from manufacturing to services. However, most of existing supply chain research focuses exclusively on the manufacturing sector. To overcome this situation, it needs to investigate and analyze service supply chain. Simulation is one of the most frequently used techniques for analysis and design of complex system. Service supply chain is complex and large systems that require an accurate designing phase. Especially, it is important to examine closely the dynamically interactive behavior of the different service supply chain components in order to predict the performance of the servcie supply chain. In this paper, we develop a conceptual model of service supply chain. Then, we present a new procedure to develop simulation model for the developed conceptual model of service supply chain, based on the UML analysis and design tools and on the ARENA simulation language. The two main characteristics of the proposed procedure are the definition of a systematic procedure to design service supply chain and of a set of rules for the conceptual model translation in an ARENA simulation language. The goal is to improve the knowledge on service supply chain management and support the simulation model development efficiency on service supply chain.

• Management Science and Financial Engineering
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• v.22 no.1
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• pp.5-12
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• 2016

We consider a time-cost tradeoff problem with multiple milestones under a chain precedence graph. In the problem, some penalty occurs unless a milestone is completed before its appointed date. This can be avoided through compressing the processing time of the jobs with additional costs. We describe the compression cost as the convex or the concave function. The objective is to minimize the sum of the total penalty cost and the total compression cost. It has been known that the problems with the concave and the convex cost functions for the compression are NP-hard and polynomially solvable, respectively. Thus, we consider the special cases such that the cost functions or maximal compression amounts of each job are identical. When the cost functions are convex, we show that the problem with the identical costs functions can be solved in strongly polynomial time. When the cost functions are concave, we show that the problem remains NP-hard even if the cost functions are identical, and develop the strongly polynomial approach for the case with the identical maximal compression amounts.

• The Journal of Bigdata
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• v.4 no.1
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• pp.1-10
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• 2019

As FTA is spreading, it is becoming more and more necessary to improve the accuracy and reliability of the country of origin information at the domestic trading stage in preparation for the actual surveys expected to surge in the near future. However, there are many problems in collecting and managing information related to origin. It is pointed out that the shortage of export-oriented profits and the incentive for issuance of FTA-related profits, as well as the lack of information on the distribution and management of origin information of domestic manufacturing companies are also pointed out as important causes. In this paper, we propose a method to improve the efficiency of management and circulation of smooth FTA origin (comprehensive) certificate of Korean companies and to improve reliability through manipulation prevention by building prototype of origin information management system based on private block chain Hyperledger. The block chain, called Distributed Ledger or Trusted Internet, provides a technical infrastructure that enables various related companies to distribute origin information with high reliability and immediate distribution in the supply chain, but research on its application is still in the beginning stage.

• Journal of Korean Society for Quality Management
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• v.51 no.1
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• pp.1-18
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• 2023

Purpose: In Part 1, the purpose of this study is to examine how a used product provider optimizes a company's profits by comparing an extended warranty to a used product only when selling a product and what it provides later. In addition, in Part 2, an empirical study can confirm the structure in which extended guarantees can work effectively by grasping consumers' purchase intention according to the time of sale of extended guarantees, which is the basic premise of the analysis model of Part 1. Methods: This study aims to conduct not only analytical studies but also empirical studies applying various statistical analysis methods using questionnaires targeting customers and potential consumers who have subscribed to extended warranty services. Results: The study showed that the profits of companies providing extended warranty services were proportional to the coefficient of the extended guarantee service value, so it is necessary to create an environment in which the effect of extended guarantee services can be well realized. In the empirical model, the higher the emotional and economic benefits are perceived, the higher the purchase intention according to the future purchase of extended guarantees. Conclusion: Through this study, various problems that may be caused by the structural diversity of the supply chain providing extended warranties in the future can be viewed and contribute to the theoretical foundation for strategic understanding.

• Asia pacific journal of information systems
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• v.7 no.1
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• pp.151-163
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• 1997

This paper deals with a reference model for a process-oriented parts supply company From the view point of SCM(Supply Chain Management), the model focuses on the integration of order management and manufacturing information. The model, considering the characteristics of manufacturing processes, separates the execution level from the planning level, and then introduces a virtual process to efficiently link the two levels. The model is operated to maximize its flexibility by the separation of planning and execution. A case study shows that our model significantly increases the productivity of the company.

• Journal of the Korean Operations Research and Management Science Society
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• v.32 no.1
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• pp.147-160
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• 2007

In this paper, the optimal decision making strategy for resource management is viewed in terms of a combined strategy of planting and producing time. A model which can be used to determine the optimal management strategy is developed, and focuses on how to design the operation of a Markov chain so as to optimize its performance. This study estimated a dynamic stochastic model to compare alternative production style and used the net present value of returns to evaluate the scenarios. The managers in this study may be able to increase economic returns by delaying produce in order to market larder, more valuable commodities.

• Industrial Engineering and Management Systems
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• v.14 no.1
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• pp.1-10
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• 2015

In this paper, we consider multi-item inventory management. When managing a multi-item inventory, we coordinate replenishment orders of items supplied by the same supplier. The associated problem is called the joint replenishment problem (JRP). One often-used approach to the JRP is to apply a can-order policy. Under a can-order policy, some items are re-ordered when their inventory level drops to or below their re-order level, and any other item with an inventory level at or below its can-order level can be included in this order. In the present paper, we propose a method for finding the optimal parameter of a can-order policy, the can-order level, for each item in a lost-sales model. The main objectives in our model are minimizing the number of ordering, inventory, and shortage (i.e., lost-sales) respectively, compared with the conventional JRP, in which the objective is to minimize total cost. In order to solve this multi-objective optimization problem, we apply a genetic algorithm. In a numerical experiment using actual shipment data, we simulate the proposed model and compare the results with those of other methods.

• Journal of Korean Society for Quality Management
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• v.47 no.1
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• pp.163-186
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• 2019

Purpose: The purpose of this study was to present a methodology for assessing the efficiency of supply chain quality management considering characteristics of defense industries to provide academic and policy implications for strengthening quality competitiveness of military supplies. Methods: Using the defense industry's empirical data, conduct an efficiency evaluation by utilizing a multi-stage DEA/Entropy Model for defense industries subject to the quality level survey of military goods manufacturers in 2017. Results: The results of this study are as follows; the first step of the multi-stage DEA model, Quality Management Performance Efficiency Analysis, shows that the CCR model and the BCC model are more efficient than the parent company. the second stage of the multi-stage DEA model showed that the CCR model was slightly more efficient than the parent company and the BCC model was more efficient than the parent.the overall efficiency value of the multistage DEA model, calculated by multipointing the efficiency value of the first stage by the second stage, was more efficient than the parent. Conclusion: The results of this study show that the efficiency of supply chian quality management performance and profitability in the defense industry can be analyzed for the first time using the multistage DEA/Entropy model to identify specific inefficiencies and support objective decision making.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.1
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• pp.81-97
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• 2004

The purpose of this study is to suggest management information through the analysis of relationships between financial characteristics and financial performance to the owners and managers of super deluxe hotels in Korea. The data of super deluxe hotels were collected by the electronic F/S announcement system. Forty-two hotels, which have financial statements for the previous three consecutive years were chosen as the sample of analysis. Return on total assets and times interest earned, asset turnover, current ratio of the super deluxe hotels are correlated. Return on total assets and asset turnover, sales growth rate, times interest earned are also correlated. And productivity and asset turnover of chain hotels are correlated. Based on this study, it can be concluded that chain hotels are maily correlated with growth ratio and activity ratio. Otherwise non-chain hotels are mainly correlated with current ratio and safety ratio.

• IE interfaces
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• v.15 no.1
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• pp.55-63
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• 2002

This paper utilizes the FIDO methodology (Function, Information, Dynamic, Organization modeling) which is an enterprise modeling tool that can describe inter-organizational interaction (specifically between prime and sub contractors in this experiment). FIDO follows the standard IDEFO rules in order to demonstrate how a cascading information flow can evolve from a customer to a prime to a subcontractor in a concurrent manner, in a supply chain environment. Background on these processes is presented, followed with the newly derived process and methodology. This is presented in a supply chain management context, and results from an actual experiment at Motorola utilizing subcontractors that supply custom machine parts is presented and reviewed.