• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.1
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• pp.64-77
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• 2013

In this paper, we propose a joint bandwidth allocation and path selection scheme for IEEE 802.16j networks in uplink with cooperative relaying, and we evaluate the performance of the proposed scheme by using OPNET based simulation in hilly terrain with heavy tree density. The proposed scheme maximizes the system throughput in uplink with cooperative relaying in IEEE 802.16j networks. Then, we transform the proposed scheme into multi-dimensional multiple choice knapsack problem (MMKP) based scheme. We also propose uplink throughput maximization scheme and MMKP based scheme without cooperative relaying. We show that the system throughput of the proposed MMKP based scheme is higher than that of link quality based scheme, and cooperative relaying provides higher system throughput than the conventional case without cooperative relaying in uplink.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.307-314
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• 2010

In this paper, a receive diversity combining technique is proposed for single-carrier frequency division multiple access (SC-FDMA)-based cooperative relay systems when discrete Fourier transform (DFT) spreading sizes for mobile station (MS) and relay station (RS) are different. The proposed technique is composed of a DFT spreading size adjustment block, a phase rotation compensation block, a channel phase compensation block, and a receive diversity combining block. The proposed technique is robust to multipath channels and can be operated with a relatively small computational complexity because receive diversity combining is performed with scalar operations in the frequency-domain. It is shown by computer simulation that the proposed receive diversity combining techniques achieve a performance gain over the conventional maximal ratio combining (MRC) techniques for SC-FDMA-based cooperative relay systems.

• The Journal of Korean Association of Computer Education
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• v.15 no.6
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• pp.65-74
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• 2012

Wiki is an online-based collaborative tool, and has been frequently used more recently as it realizes the paradigm of web 2.0 in educational context. Especially, wiki promotes collaborative knowledge building which is the major interest of this study. The purpose of this research is to investigate the relationships among academic self-efficacy, self-efficacy for group work, wiki anxiety, participation in wiki activity, and learning achievement. Fifty nine college students participated in the wiki activity, and the data from fifty three were used for the multiple regression and path analysis. The results reported that academic self-efficacy and wiki anxiety affected participation in wiki activity, and these two variables also had indirect effects on learning achievement, mediated by participation.

• International Area Studies Review
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• v.21 no.4
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• pp.295-316
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• 2017

The job creation is one of the important issue from the public and private sector. For the job opportunity, the private sector would contribute to create plentiful opportunities for job-seekers. Especially, foreign donor countries has fostered the development consulting firm in the private sector with the legal and institutional support. As the result, it has played the important role to create the job opportunity for whoever want to find the way in the international development cooperation. However, South Korea does not yet make the environment as much as foreign donor countries. Hence, this study aims to analyze the case on fostering the development consulting firm in the international development cooperation to draw the political implication for South Korea. With this, the result of the study is significant to rebuild the index on the impact evaluation of the employment that is fit to the international development cooperation. Thus, foreign donor countries suggests that fostering the development consulting firms in the international development cooperation should be based on the political and institutional support, tied network, and sustainable supply of human resources. Indeed, the improvement of the index on the impact evaluation of the employment would contribute to correctly measure the impact from the development consulting firm in the private sector.

• The Science & Technology
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• no.12 s.439
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• pp.34-35
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• 2005

• Nuclear industry
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• v.38 no.1
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• pp.49-51
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• 2018

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.185-196
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• 2015

In a study of the existing Collaboration, U-I Collaboration linkage(LINK) has a width of the various channels through continuous mutual cooperation by the path-dependency. U-I Collaboration linkage(LINK) through the various channels is more powerful, whereas this increase trade-related barriers. In other words, It has been discussed in many literatures about the U-I Collaboration linkage(LINK). However, relatively a study on the factor of the barrier about U-I Collaboration linkage(LINK) is a minority. Given the importance of policies to establish an association of industry-university cooperation and support system, the lack of research on the obstacles to U-I Collaboration linkage(LINK) will be a serious obstacle for designing effective policies. This paper examines the existing literature about the width of mutual cooperation and the barrier of U-I Collaboration, analyze to lower the barrier of U-I cooperation through POB(Positive Organization Behavior) of university administration. In conclusion, we would like to suggest the policy implications.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.211-223
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• 2018

Mobile relay systems have been adopted by $4^{th}$ generation mobile systems as an alternative method to extend cell coverage as well as to enhance the system throughput at cell-edges. In order to achieve such performance gains, the mobile relay systems require path selection and resource allocation schemes that are specifically designed for these systems which make use of additional radio resources not needed in single-hop systems. This paper proposes an integrated path selection and resource allocation scheme for LTE-Advanced relay systems using collaborative communication. We first define the problem of maximizing the downlink throughput of LTE-Advanced relay systems using collaborative communication and transform it into a multi-dimensional multi-choice backpacking problem. The proposed Lagrange multiplier-based heuristic algorithm is then applied to derive the approximate solution to the maximization problem. It is shown through simulations that the approximate solution obtained by the proposed scheme can achieve a near-optimal performance.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.83-120
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• 2008

Small and medium sized enterprises' (SMEs) environmental performance and activities have been often of great concern toward sustainability as they have been playing a critically important role in the economic and industrial development. Among many initiatives to engage SMEs into the sustainability framework, Supply Chain Environmental Management (SCEM) of large companies has a great potential to persuade SMEs to adopt environmentally improved activities. This study investigated the relationship between SCEM approaches of large companies and environmental activities of SMEs in the Korean electronics industry. A postal questionnaire survey was used as a data collection method, and factor analysis and regression analysis were applied to analyse the collected data. The empirical findings suggested that SCEM approaches of large companies have positive impacts on environmental activities of SMEs. Among SCEM approaches, the collaborative approach was more effective than the arm's-length approach. Additionally, this study found positive impacts of trans-national SCEM approaches on SMEs' environmental activities.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06d
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• pp.58-62
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• 2007

기존의 무선 Ad-hoc 네트워크의 연구는 라우팅기법에 중심으로 이뤄지고 있다. 그러나 기존의 연구들은 네트워크를 구성하는 각 요소들이 우호적이며 상호 협력적인 상황을 가정하여 연구가 이루어지고 있다. 그러나 최근 연구에는 안전한 통신을 보장하기 위한 보안 알고리즘의 필요성에 집중되고 있다. 무선 Ad-hoc 네트워크에서의 악의적인 노드를 식별하는 방안들은 정상적인 노드임에도 불구하고 거짓으로 신고했을 때 확인절차 없이 경로를 재탐색하여 최적의 경로를 변경시킴으로서 최적의 전송환경을 활용하지 못하는 문제점이 있다. 본 논문에서는 다중경로 기반의 보안경로 탐색 프로토콜인 MP-SAR 프로토콜을 이용하여 보안경로에서는 악의적인 노드를 검증하고, 유효한 최단경로를 통해 데이터전송을 하는 기법을 제안하고자 한다. 제안한 기법을 적용함으로써 노드에 대한 신고가 있을 때 확인과정을 거쳐 불필요하게 경로를 재탐색하는 과정을 줄일 수 있다.