• Journal of the Korea Safety Management & Science
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• v.11 no.3
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• pp.139-148
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• 2009

In a real-life supply chain environment, demand forecasting is usually represented by probabilistic distributions due to the uncertainty inherent in customer demands. However, the customer demand used for an actual supply chain planning is a single deterministic value for each of periods. In this paper we study the choice of single demand value among of the given customer demand distribution for a period to be used in the supply chain planning. This paper considers distributed multi-echelon supply chain and the objective function of this paper is to minimize the total costs, that is the sum of holding and backorder costs over the distribution network under the service level constraint, by using demand selection scheme. Some useful findings are derived from various simulation-based experiments.

• Journal of the Korea Safety Management & Science
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• v.8 no.5
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• pp.139-150
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• 2006

The aim of this study is to establish an efficient distribution planning for a capacitated multi-stage supply chain. We assume that the demand information during planning horizon is given a deterministic form using a certain forecasting method. Under such a condition, we present a cost effective heuristic method for minimizing chain-wide supply chain inventory cost that is the sum of holding and backorder costs by using look-ahead technique. We cope with the capacity restriction constraints through look-ahead technique that considers not only the current demand information but also future demand information. To evaluate performance of the proposed heuristic method, we compared it with the extant research that utilizes echelon stock concept, under various supply chain settings.

• Annual Conference on Human and Language Technology
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• 2013.10a
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• pp.9-12
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• 2013

본 논문에서는 한국어 형태소 분할 및 품사 태깅 방법을 위한 결합 모델로 Semi-CRF와 Linear-chain CRF에 대한 초기 비교 실험을 수행한다. Linear-chain방법은 출력 레이블을 형태소 분할 정보와 품사 태그를 조합함으로써 결합을 시도하는 방식이고, Semi-CRF는 출력의 구조가 분할과 태깅 정보를 동시에 포함하도록 표현함으로써, 디코딩 과정에서 분할과 태깅을 동시에 수행하는 방법이다. Sejong품사 부착말뭉치에서 비교결과 Linear-chain방법이 Semi-CRF방법보다 우수한 성능을 보여주었다.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.5
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• pp.265-272
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• 2013

This paper addresses a control allocation method for fault-tolerant control by redistributing redundant control surfaces. The proposed method is based on a classical daisy chain approach for the compensation of faulty actuators. The existing daisy chain method calculates a desired moment according to a number of actuator groups. However, this method has a significant limitation; that is, any faulty actuator belonging to the last actuator group cannot be compensated, since there is no more redundant actuator group that can be used to generate the required moments. In this paper, a modified daisy chain method is proposed to overcome this problem. Using the proposed method, the order of actuator groups is readjusted so that actuator groups containing any faulty actuator are always placed in an upper group instead of the last one. A set of simulation results with an F-18 HARV aircraft demonstrate that the proposed method can achieve better performance than the existing daisy chain method.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.2
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• pp.11-17
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• 2018

IDS/IPS and networked computer systems are playing an increasingly important role in our society. They have been the targets of a malicious attacks that actually turn into intrusions. That is why computer security has become an important concern for network administrators. Recently, various Detection/Prevention System schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems is useful for existing intrusion patterns on standard-only systems. Therefore, probe detection of private clouds using BlockChain has become a major security protection technology to detection potential attacks. In addition, BlockChain and Probe detection need to take into account the relationship between the various factors. We should develop a new probe detection technology that uses BlockChain to fine new pattern detection probes in cloud service security in the end. In this paper, we propose a probe detection using Fuzzy Cognitive Map(FCM) and Self Adaptive Module(SAM) based on service security using BlockChain technology.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.5
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• pp.511-520
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• 2015

Inventory, cost, and the level of service are three interrelated key metrics that most supply chain organizations are striving to optimize. One way to achieve this goal is to create a simulation model to conduct sensitivity analysis and optimization on several different supply chain policies that can be implemented in actual operation. In this paper, a case of Xerox global supply chain modeling and analysis to assess several "what if" scenarios for the consumable policy safety stock is presented. The simulation model, combined with analytical cost model and optimization module, is used to optimize the policy safety stock level to achieve the lowest total value chain cost. It was shown quantitatively that the policy safety stock can be reduced, but it is offset by the inbound premium transportation cost to expedite supplies in shortage, and the outbound premium transportation cost to send supplies to customers via express shipment, requiring fine balance.

• Industrial Engineering and Management Systems
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• v.12 no.2
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• pp.85-94
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• 2013

This research investigates the supply chain contract between a distributor and a supplier in which the selling period is relatively short in comparison with long production lead time. At the first stage, supplier who is a Stackelberg leader offers the distributor a contract with a set of parameters, and subjected to those parameters, the distributor places the number of initial orders as well as options. In order to purchase the option, the distributor pays non-linear option premium price with respect to the number of purchased options. At the second stage, based on realized demand, the distributor has the right to exercise option as either put or call which is limited up to the number of purchased options. The wholesale price contract is used as a benchmarking contract. This research has confirmed that the supply chain contract with a non-linear option premium price can help to coordinate the supply chain.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.877-887
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• 2012

The Bank of Korea changed its method of GDP estimation from a fixed-weighted to a chain-weighted measure in 2009. The fixed-weighted method had had problems such as substitution bias and the rewriting of economic history. As a result of the change, annual growth rates calculated using the chain-weighted method from 1970 through 2008 turned out to be 0.8%p higher on average than the existing rates. The quarterly average chain-weighted growth rates were 0.19%p higher than the fixed-weighted ones, but they changed in the same directions. In this paper we analyze whether the differences in rates between the two calculation methods would bring about a difference in the cyclical characteristics of GDP. We conclude that although there were differences in growth rates after introduction of the chain-weighted method, there was no difference in the cyclical fluctuation.

• Asia pacific journal of information systems
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• v.16 no.3
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• pp.1-27
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• 2006

In supply chains, collaboration between buyer and supplier can improve firms' ability of supply chains to their objectives and competitive advantages. A key factor in collaboration in supply chain is to identify buyer relationships and supply relationships as antecedents of the factor collaboration. We analyzed data collected from buyers and suppliers sampled from a mobile networks industry in Korea and found that the level of collaboration comes from strong relationships between two parties and the collaboration enhances the supply chain performances. However, buyer relationships and supplier relationships have indirect impacts on trading partners' performance through collaboration whereas both have direct impacts on one's performance. Therefore to enhance supply chain performances, supplier's operational efficiency and buyer satisfaction, firms of buyers and suppliers should consider pursuing practical and substantial collaboration along with buyer-supplier relationships.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.666-673
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• 1991

The elongation of the chain length at 2'position of aminothiazolylacetamido group of cephalosporin antibiotics was achieved. The derivatives with elongated side chain at 2'position were successfully synthesis and their in vitro activities were evaluated. It is indicated that there is an optimum range of the chain length in order to exhibit higher biological activities. This result could open a possibility for the development of the cephalosporin antibiotics with higher activities by further variation of the substituents at other positions. The cephalosporin derivatives with a simple (relatively non-functionalized) side chain as well as with a linear extended side chain were also prepared. Low activities of these derivatives led to a conclusion that either simple (non-functionalized) change or linear elongation of the side chain does not enhance the antibacterial activities.