• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.4
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• pp.11-33
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• 2013

We analyzed the structures and properties of the global financial market networks using social network analysis approach. The Minimum Spanning Tree (MST) lengths and networks of the global financial markets based on the correlation coefficients have been analyzed. Firstly, similar to the previous studies on the global stock indices using MST length, the diversification effects in the global multi-asset portfolio can disappear during the crisis as the correlations among the asset class and within the asset class increase due to the system risks. Second, through the network visualization, we found the clustering of the asset class in the global financial markets network, which confirms the possible diversification effect in the global multi-asset portfolio. Meanwhile, we found the changes in the structure of the network during the crisis. For the last one, in terms of the degree centrality, the stock indices were the most influential to other assets in the global financial markets network, while in terms of the betweenness centrality, Gold, Silver and AUD. In the practical perspective, we propose the methods such as MST length and network visualization to monitor the change of the correlation risk for the risk management of the multi-asset portfolio.

• International Commerce and Information Review
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• v.14 no.2
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• pp.55-79
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• 2012

The previous studies based on a resource-based view of firm highlighted the role of resources within a firm in creating and sustaining competitive advantage. Recent research, however, the relational view points to the importance of inter-firm sources(or relational capital) in creating firm competitiveness. In international business field, the studies on born-global firms also states that when firms are lack of ownership-specific advantages in their internationalization process, they resort to the external partners and social networks to complement their resource scarcity. By adopting the relational view and born-global firms concept, a network-based approach needs to be applied to explain the international strategy of Korean service firms. This is because most of Korean service firms own less ownership-specific advantages than global competitors. This study proposes Korean firms' global network building and exploiting strategy to enhance their international stages of development. The network, for example, Global Korean Tourism Network, enables network members access to the valuable resources and capabilities they are lack of when undergoing internationalization process. This study's contribution is along two dimension. First, even global Korean network is emerging as a major issue in recent years, we could not figure out how to build global Korean network for service firms. This studies gives an answer. Second, we derived what benefits can be gained from the network if Global Korean Tourism Network is developed for hotel, tourism, convention firms' internationalization.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7A
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• pp.688-696
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• 2010

The Proxy Mobile IPv6 (PMIPv6) is a network localized mobility management protocol that is independent of global mobility management protocols. In a single mobility domain (LMD), the mobile node (MN) is not involved in any IP mobility-related signaling and uses only its PMIPv6 home address for all its communication. Subsequently, when the MN moves into another LMD, the MN must change its PMIPv6 home address. In such a circumstance, host-based mobility signaling is activated. Thus, the nature of the network-based mobility of the PMIPv6 cannot be retained. Additionally, if the MN does not support global mobility, it cannot maintain communication with its correspondent node (CN). In this paper, we propose a solution for global mobility support in PMIPv6 networks, called Global-PMIPv6 that allows current communication sessions of a MN without mobility protocol stacks to be maintained, even when the MN moves into another LMD. Thus, Global-PMIPv6 retains the advantages of the PMIPv6 for global mobility support. We then evaluate and compare network performance between our proposed solution and PMIPv6.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.3
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• pp.427-439
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• 2019

This study investigated the semantic network based on the focus of the fashion image and SNS text utilized by global SPA brands on the last seven years in terms of the quantity and quality of data generated by the fast-changing fashion trends and fashion content-based media environment. The research method relocated frequency, density and repetitive key words as well as visualized algorithms using the UCINET 6.347 program and the overall classification of the text related to fashion images on social networks used by global SPA brands. The conclusions of the study are as follows. A common aspect of global SPA brands is that by looking at the basis of text extraction on SNS, exposure through image of products is considered important for sales. The following is a discriminatory aspect of global SPA brands. First, ZARA consistently exposes marketing using a variety of professions and nationalities to SNS. Second, UNIQLO's correlation exposes its collaboration promotion to SNS while steadily exposing basic items. Third, in the case of H&M, some discriminatory results were found with other brands in connectivity with each cluster category that showed remarkably independent results.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.33-39
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• 1995

One dimensional optimization problem is considered, we propose a method to find the global minimum of one-dimensional function with on gradient information but only the finite number of input-output samples. We construct a learning network which has a good learning capability and of which global maximum(or minimum) can be calculated with simple calculation. By teaching this network to approximate the given function with minimal samples, we can get the global minimum of the function. We verify this method using some typical esamples.

• Journal of Internet Computing and Services
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• v.10 no.5
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• pp.1-12
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• 2009

A routing policy based on BGP community routing permits to select a specific route for particular network by making use of user-defined routing policies. Especially, community based routing policy is recently getting a great concern to enhance overall performance in the global research networks which are generally inter-connected large number of different characterized networks. In this paper, we analyze the community routing which has been applied in existing global research networks in the network performance point of view, and catch hold of problems caused by the routing performance in a new global research network. Then, we suggest an effective community routing policy model along with an interconnection architecture of research networks, in order to make correct some wrong routings and resolve an asymmetric routing problem, for a new global research network. Our work is expected to be utilized as an enabling base technology to improve the network performance of future global research networks as well as commercial networks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5B
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• pp.491-497
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• 2004

In this Paper, we W a Hovel global traffic control architecture to isolate malicious network attacks and protect network infrastructure in Internet backbone networks. Unlike existing methods based on individual packets or flows, since the proposed detection and control methods are operated on the aggregate traffic level, the computational complexity can k significantly reduced, and they are applicable to develop a global defense architecture against network attack. Experimental results show that the proposed scheme can detect the network attack symptoms very exactly and quickly and protect the network resources as well as the normal traffic flows very efficiently.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06d
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• pp.315-318
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• 2011

In this work, a VN-based IPTV service delivery network containing a novel VNT was designed, This VN-based IPTV service delivery network utilizes current resources that can be easily obtained by IPTV providers and organizes these resources in a more efficient manner, We also developed a three-stage VN allocation scheme to reduce the complexity of topology design and allocation.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.06a
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• pp.63-66
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• 2018

Recently, a convolutional neural network (CNN) models at single image super-resolution have been very successful. Residual learning improves training stability and network performance in CNN. In this paper, we compare four convolutional neural network models for super-resolution (SR) to learn nonlinear mapping from low-resolution (LR) input image to high-resolution (HR) target image. Four models include general CNN model, global residual learning CNN model, local residual learning CNN model, and the CNN model with global and local residual learning. Experiment results show that the results are greatly affected by how skip connections are connected at the basic CNN network, and network trained with only global residual learning generates highest performance among four models at objective and subjective evaluations.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.315-316
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• 2023

본 논문에서는 딥러닝을 활용하여 KBO (Korea Baseball Organization)의 다음 시즌 플레이오프 진출 확률을 예측하는 Deep Neural Network (DNN) 시스템을 설계하고 구현하는 방법을 제안한다. 연구 방법으로 KBO 각 시즌별 데이터를 1999년도 데이터부터 수집하여 분석한 결과, 각 시즌 데이터 중 경기당 평균 득점, 타자 OPS, 투수 WHIP 등이 시즌 결과에 유의미한 영향을 끼치는 것을 확인하였다. 모델 설계는 linear, softmax 함수를 사용하는 것보다 relu, tanh, sigmoid 함수를 사용했을 때 더 높은 정확도를 얻을 수 있었다. 실제 2022 시즌 결과를 예측한 결과 88%의 정확도를 도출했다. 폭투의 수, 피홈런 등 가중치가 높은 변수의 값이 우수할 경우 시즌 결과가 좋게 나온다는 것이 증명되었다. 본 논문에서 설계한 이 시스템은 KBO 구단만이 아닌 모든 야구단에서 선수단을 구성하는데 활용 가능하다고 사료된다.