• Industrial Engineering and Management Systems
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• v.14 no.2
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• pp.129-158
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• 2015

It is necessary for retailers to determine the optimal ordering policy of products considering supply disruptions due to a natural disaster and a production process failure as quality and machine breakdowns. Under the situation, a dualsourcing supply chain (DSSC) is one of effective SC for retailers to order products reliably. This paper proposes the optimal ordering policy of a product in a DSSC with a retailer and two manufacturers. Two manufacturers may face supply disruptions due to a natural disater and a production process failure after they received the retailer's order of products. Here, two scenarios of demand information of products are assumed: (i) the demand distribution is known (ii) mean and variance of the demand are known. Under above situations, two types of DSSC are discussed. Under a decentralized DSSC (DSC), a retailer determines the optimal ordering policy to maximize his/her total expected profit. Under the integrated DSSC (ISC), the optimal ordering policy is determined to maximize the whole system's total expected profit. Numerical analysis investigates how demand information and supply disruptions affect the optimal decisions under DSC and ISC. Besides, profitability of supply chain coordination adjusting the wholesale price is evaluated to encourage the optimal decision under ISC.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.3
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• pp.117-129
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• 2018

This study examines the impact of severe weather on lean supply chains. First, this paper reviewed the literature on the disruptions and damages that severe weather events cause on supply chain. Then, several recent examples of lean supply chain disruptions due to severe weather were discussed. The results of the study indicated that the frequency of weather related disasters is increasing and extreme weather events will increase potential risks to supply chains. First, building organizational resilience will help firms look beyond efficiency and profits in managing lean supply chains. Second, the concept of sole sourcing may need rethinking to maintain a supply chain that is lean and resilient. Third, organizations must plan ahead for supply chains in unpredictable weather. Fifth, communication is a key for anticipating and avoiding the impact of severe weather. This study proposes of a set of strategies, both theoretical and practical, that business firms should develop to effectively prevent and respond to severe weather related disruptions in lean supply chains.

• Journal of Contemporary Eastern Asia
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• v.20 no.2
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• pp.237-258
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• 2021

The COVID-19 pandemic has highlighted the risks of an over-concentration of supply chains in one country. It has motivated stakeholders to pursue diversification strategies. However, a paradox exists. Stakeholders have shied away from a complete decoupling and preferring to selectively enhance economic ties with China. This article explores this paradox by examining supply chain concentration in China as a form of asymmetric interdependence and the countermeasures from the U.S., Japan, Australia, and India to minimize vulnerabilities. It argues that while the COVID-19 disruptions have brought to light the risk of supply chain overconcentration in China, countermeasures are also driven by coercive diplomacy and the deepening U.S.-China rivalry. The paper also examines the feasibility of diversification efforts by focusing on the capacity and capabilities of alternative supply chain hubs. It finds that while states are actively seeking ways to prevent China from using asymmetric interdependence of supply chains and trade to gain political leverage, there are structural limits to the degree of diversification in the short to mid-term.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.667-672
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• 2009

In case of high-levelled platform in the urban railway system, a certain width of gap is inevitably formed between the train and the platform, and the gap gets wider when it is concerned with curved portion of the tracks at platform. This gap greatly contributes to decrease of passengers' safety while boarding and alighting a train. In particular, it endangers children's safety. Gap filler system is often fitted out to minimize gap and to overcome this safety problem at platform. However, as existing gap fillers are in most case structurally complex and organized to be powered from separate supply unit, there are a range of non-favorable points from the viewpoint of cost, installation and maintenance. In addition, existing gap fillers are due to cause disruptions in operation of train, with failures such as malfunctioning of control system. In this study, the authors will review on the gap filler applicable to the platforms of various height types, which neither requires any modifications of the train nor causes any operational disruptions. The proposed gap filler system here is a by-stage retractile type and based on the idea of interlocking it with train doors open-close mechanism, without any additional power supply unit or control system.

• Journal of the Korean Operations Research and Management Science Society
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• v.42 no.2
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• pp.19-34
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• 2017

In this study, we develop an optimal sourcing strategy considering compensation orders to mitigate the supply chain disruption risks. We considered two-echelon supply chain consisting of a single buyer and multiple suppliers who have fixed transaction cost and probabilistic disruption risks. Under this setting, we provide the joint optimization method to determine the number of suppliers and the order quantities. Through numerical examples, we provide managerial implications on the sourcing strategy by investigating changes in the order quantities and the number of suppliers due to the degree of supply chain disruption risks.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.2
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• pp.79-90
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• 2018

This study aims to provide the system to help decision making by finding key indicators used in land supply and demand surveys, and by developing storage priority areas and projects. As problems arose such as the rising cost of public projects or disruptions to business progress due to the rapid rise in land prices and the cost of compensation for public projects in the past, a new land policy was adopted and the land reserve system was established in 2009. At that time, The bank's goal was to conserve 2 trillion won of land per year, but the result was sluggish as it accumulated a total of 1.6 trillion won from 2009 to 2015. The reason for this sluggish result is that the type and quantity of indicators are still extensive and the survey of land supply and demand has a problem of poor utilization. In order to make up for the sluggishness, we made key indicators used in land supply and demand surveys using the question investigation, and analyzed the priority of the project areas. This study provide the system to help decision making by finding key indicators used in land supply and demand surveys, and the priorities of project areas.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.324-329
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• 2015

Though the supplier diversification is considered as a vital tool to mitigate the risk due to supply chain disruptions, there are results which show the optimality of the sole sourcing. This paper further generalizes the results to show that the sole sourcing is optimal under very mild conditions. Discussion on why the sole sourcing is optimal is given with the insight on the value of supplier diversification.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.269-276
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• 2022

The robustness of a supply chain (i.e., the ability to cope with external and internal disruptions and disturbances) becomes more critical in ensuring the success of a construction project because the supply chain of today's construction project includes more and diverse suppliers. Previous studies indicate that topological features of the supply chain critically affect its robustness, but there is still a great challenge in characterizing and quantifying the impact of network topological features on its robustness. In this context, this study aims to identify network measures that characterize topological features of the supply chain and evaluate their impact on the robustness of the supply chain. Network centrality measures that are commonly used in assessing topological features in social network analysis are identified. Their validity in capturing the impact on the robustness of the supply chain was evaluated through an experiment using randomly generated networks and their simulations. Among those network centrality measures, the PageRank centrality and its standard deviation are found to have the strongest association with the robustness of the network, with a positive correlation coefficient of 0.6 at the node level and 0.74 at the network level. The findings in this study allows for the evaluation of the supply chain network's robustness based only on its topological design, thereby enabling practitioners to better design a robust supply chain and easily identify vulnerable links in their supply chains.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.109-120
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• 2020

The supply chain without digitization is just a series of discrete, siloed steps taken through marketing, product development, manufacturing, and logistics, and finally into the hands of the customer. Digitization brings down those walls, and the chain becomes a completely integrated network fully transparent to all the parties involved. The ulitimate goals of digitizatized supply chain management are velocity and visibility. This network will depend on a number of key technologies including integrated planning and execution systems, supply chain analytics, autonomous logistics, smart warehousing and factory, etc, enabling companies to react to disruptions in the supply chain, and even anticipate them, by fully modeling the network, creating "what-if" scenarios, and adjusting the supply chain in real time as conditions change. This paper presents a number of studies on digitalization of supply chains and provides a discussion on issues raised in the process of technology adoption. Implications of the study findings are also provided.

• Korea Trade Review
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• v.47 no.6
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• pp.269-289
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• 2022

The COVID-19 pandemic has disrupted supply chains across the world. When the pandemic broke out, the disruptions were mainly due to the lockdowns imposed in various countries. The WTO has predicted that the pandemic might cause world trade to decline by 13 to 32 per cent in 2020. This paper will examine the implications of COVID-19 on digital trade, particularly the use of blockchain in the Asia Pacific. The Asia Pacific (particularly Singapore and Hong Kong) is a leader in the use of digital technologies. This paper will thus attempt to draw out lessons from the first movers for the rest of Asia. It will examine the bottlenecks in the application of this technology in the Asia Pacific countries, and the need for regulatory changes in the Asia-Pacific. It will trace the technology's barriers to adoption, both as regards interoperability, and regulatory framework. The advantages of blockchain technology in trade finance are clear; it can promote trade efficiency, mitigate risk and expand trade to other regions. However, earlier efforts to introduce digital technologies have failed. More collaborative efforts are required, so that networks can connect seamlessly on a single technology platform, and meet the demand for trade finance. The COVID-19 pandemic seems to have provided an enabling environment for the intensification of digital efforts, increasing their urgency; should these measures indeed successfully occur, they will improve the resiliency of supply chains across the region.