• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.1861-1870
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• 2013

A climate change-driven increased hydrological variability has been widely acknowledged over the past decades. In this regards, rainfall simulation techniques are being applied in many countries to consider the increased variability. This study proposed a Homogeneous Hidden Markov Chain(HMM) designed to recognize rather complex patterns of rainfall with discrete hidden states and underlying distribution characteristics via mixture probability density function. The proposed approach was applied to Seoul and Jeonju station to verify model's performance. Statistical moments(e.g. mean, variance, skewness and kurtosis) derived by daily and seasonal rainfall were compared with observation. It was found that the proposed HMM showed better performance in terms of reproducing underlying distribution characteristics. Especially, the HMM was much better than the existing Markov Chain model in reproducing extremes. In this regard, the proposed HMM could be used to evaluate a long-term runoff and design flood as inputs.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.2
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• pp.152-163
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• 2005

The focus of enterprise collaboration of supply chain management, has changed from integrating and exchanging business information to integrating and managing business processes between business partners. However, the collaboration is difficult due to the inherent complexity such as diverse business processes and dynamic business environments. To settle these problems, a reference model based enterprise architecture framework for the collaboration of supply chains is proposed in this paper. The supply chain collaboration framework is composed of three reference models capturing the different views of supply chain collaboration: supply process reference model, service component reference model, and technology and standard reference model. As the framework adapts the OMG's metadata architecture, the processes in the supply chain can be extended and integrated with other value chains, such as design chains, when it is necessary. Using the proposed framework, business managers can rapidly integrate and manage their business processes with their suppliers and customers.

• Korean Management Science Review
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• v.23 no.1
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• pp.135-152
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• 2006

Over the last decade, the field of supply chain management (SCM) and e-business has received an enormous amount of attention from practitioners and academicians. However, little has been known about how and to what extent small- to medium-sized enterprises (SMEs) are implementing SCM initiatives and e-business practices. This paper proposes a comprehensive research model and presents the survey results of these practices of SMEs located in Wisconsin and illinois, U.S., In terms of competitive strategy and priority, value chain activity priority, supply chain and e-business integration focus, SCM best practices implementation focus and challenges, and business performance. The analysis reveals several valuable insights into how SMEs should run their businesses in today's volatile, rapidly changing customer economy.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3110-3125
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• 2014

Network coding improves TCP's performance in lossy wireless networks. However, the complex congestion window evolution of network coded TCP (TCP-NC) makes the analysis of end-to-end throughput challenging. This paper analyzes the evolutionary process of TCP-NC against lossy links. An analytic model is established by applying a two-dimensional Markov chain. With maximum window size, end-to-end erasure rate and redundancy parameter as input parameters, the analytic model can reflect window evolution and calculate end-to-end throughput of TCP-NC precisely. The key point of our model is that by the novel definition of the states of Markov chain, both the number of related states and the computation complexity are substantially reduced. Our work helps to understand the factors that affect TCP-NC's performance and lay the foundation of its optimization. Extensive simulations on NS2 show that the analytic model features fairly high accuracy.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.2
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• pp.113-127
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• 2006

We consider an integrated supply chain model in which multiple suppliers replenish items for a single buyer's demand. Also the buyer specifies a basic replenishment cycle and the suppliers replenish the items only at those time intervals. Namely, we propose a model to study and analyze the benefit by coordinating supply chain inventories through the basic replenishment cycle time. The objective of this model is to minimize the total relevant annual cost of the integrated inventory model. After developing proposed coordinated models, we suggest heuristics for searching the solutions of our models. Finally, numerical and computational experiments for each policy are carried out to evaluate the benefits of those models and the compensation policy is addressed to share the benefits.

• IE interfaces
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• v.13 no.3
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• pp.348-357
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• 2000

SCM(Supply Chain Management) is a new approach to satisfy customers via an integrated management for the whole business processes of the manufacturing from the raw material procurement to the product or service delivery to customers. Typically the semiconductor industry is the one whose supply chain network is distributed all over the world, and its manufacturing process has the particular characteristics which has to be considered in the modeling of supply chain. In this paper we suggest the push and pull type supply chain models based on the manufacturing characteristics and their mathematical formulation for the semiconductor industry. Push supply chain model pursuits the high throughput and the balance of the WIP flow, and pull supply chain model does to minimize the total cost of order-based manufacturing, distribution and transportation process in order to meet customer's request appropriately.

• Journal of Korean Society for Quality Management
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• v.28 no.4
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• pp.204-222
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• 2000

Supply Chain Management is a process-oriented concept, integrated approach to procuring, producing, and delivering products and services to customers. Supply Chain Management covers the management of material, information, and funds flows. A strategic supply chain management produces for value maker and the ultimate customer. One aim of this paper is to determine the effect of contract parameters on the quality of the end product of the supplier-producer chain. The supply chain management is viewed as a single entity rather fragmented. This research constructed model the relationship of supply chain management to quality management. The questionnaire were tested with survey of supplier's employee and the result were analyzed using SEM(Structural Equation Model). As a result, Quality performance positively depends on the communication, coordination, and process management between the supplier and the producer.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.4
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• pp.323-330
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• 2011

Globalization of market and diversification of customers' needs make enterprises to collaboration of participants in supply chain. To establish collaboration, supply chain must have the flexibility and reconfigurability, which are supported by fractal based supply chain management (FrSCM). In this paper, base on the FrSCM, formulation of trust model among the enterprises in the supply chain, and development of profit sharing strategies in the supply chain based on the trust model are investigated. To evaluate trust model, generation of enterprise's goal and its description, extraction and systematic composition of trust factors and trust evaluation are investigated. Based on the developed model, we developed the fuzzy inference engine to evaluate the trust value in terms of numerical value. And then revenue sharing strategies are developed based on the fractal concept and trust model for the collaborative SCM. The fractal concept is used to obtain the optimal production and transportation plans. In addition, the trust model will be integrated into the RS model. In such an RS model, the supply chain will obtain the maximum total profit and profit of each participant depends on its trust value.

• Industrial Engineering and Management Systems
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• v.11 no.1
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• pp.54-69
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• 2012

Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

• The Journal of Fisheries Business Administration
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• v.34 no.1
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• pp.87-115
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• 2003

Korean fisheries societies have had many difficulties for economic, social, and living circumstances. The government has tried many projects to improve these circumstances. But the results of the projects did not come up to his expectation. Recently, blue tourism is emerging as an alternative for improving these circumstances. So we applied a tourism value chain model for identifying what value activities and resources needed. According to the tourism value chain model, it was identified that there were six different value activities, i. e. advertising, reserving, moving, experiencing, returning, and after services of blue tourism. To identify which of the resources are sufficient or not in Korean blue tourism, we compared the required resources with actual ones. It was identified that Korean fisheries societies have so sufficient H/W related resources, but not IT related S/W resources, humanware-based resources, some industrial H/W resources and sociocultural resources. Therefore, Korean blue tourism will be activated, we have to concentrate our efforts on supplementing some scant blue tourism resources, i.e. S/W and humanware related resources and developing a variety of tourism programs to H/W resources. Generally, sustainable tourism needs all of S/W, H/W, and humanware resources. So we suggest several policies for the aspects of S/W, H/W, and humanware resources to activate blue tourism. But before carrying these policies out, they should be tested by field studies. And tourism motivations will be also studied because effective tourism marketing is impossible without an understanding of consumers' motivations.