• Journal of the Korean Society for Library and Information Science
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• v.42 no.4
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• pp.73-94
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• 2008

There are more than 2 million blind and partially disabled people in Korea. They need access to books and information for all the same reasons as non-disabled persons: for lifelong learning, for social activity, for leisure, and to play a full part in society. In considering these realities, this paper has suggested the various strategies and plans to build and operate a cooperative library service network for the disabled persons. In addition, author commented on the subsequent actions for implementing the cooperative service model.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.6
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• pp.15-21
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• 2011

Cooperative diversity system can be applied to an ad-hoc network for reduction of the power consumption, for expansion of the communication range, and for improving the system performance. In a selection relay cooperative diversity system which selects the maximal SNR(Signal-to-noise ratio) relay for transmitting the source information, the selected strong relay transmits continuously under slow fading channel, consequently it reduces the network lifetime. To overcome this defect, recently the uniform power relay selection has been studied to expand the network life time. We apply the uniform power relay selection to a DOT(Double opportunistic transmit) cooperative system that select the transmit relays, of which the SNR of the transmit relays exceed both of the source-relay and the relay-destination threshold. And the performance of the system is analytically derived. The performance comparisons are made among SC(Selection combining), MRC(Maximal ratio combining), and uniform power relay selection of the cooperative diversity system. We noticed that the performance of the uniform power relay selection is inferior to that of others. It is interpreted that the uniform transmit opportunity to the selected relays for extension of the network lifetime degrades the performance.

• ETRI Journal
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• v.34 no.1
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• pp.102-105
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• 2012

To serve the growing demand of the bidirectional information exchange, we propose a single relay selection (RS) scheme for physical-layer network coding (PNC) in a bidirectional cooperative network consisting of two sources and multiple relays. This RS scheme selects a single best relay by maximizing the bottleneck of the capacity region of both information flows in the bidirectional network. We show that the proposed RS rule minimizes the outage probability and that it can be used as a performance benchmark for any RS rules with PNC. We derive a closed-form exact expression of the outage probability for the proposed RS rule and show that it achieves full diversity gain. Finally, numerical results demonstrate the validity of our analysis.

• The Journal of Information Systems
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• v.15 no.3
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• pp.159-174
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• 2006

Employment rate of graduating students has been one of the most important issues at universities. Recently interest on internship abroad has been increased significantly due to globalization of the society In particular, central and local governments have developed policies and encouraged university students to participate in internships abroad. However, activities and resources for internships abroad are very limited to a few organizations. This paper investigated the current status of internship in the U.S. and Korea. Then, this paper analyzed differences in demand and supply of the internship and matching mechanism of the internship between the U.S. and Korea. From the results of those analyses, this paper developed an international network model which can help effective and efficient increase in the demand and supply of the internship as well as the internship matching mechanism in Korea. This network model utilizes international NGOs in order to develop internationally cooperative environment. This model provides mechanism for (1) effectively identifying intern applicants who like to work abroad and evaluating thent (2) effectively identifying new internship positions and evaluating companies which plan to hire interns, (3) efficiently matching demand for and supply of internship by identifying appropriate candidates, (4) monitoring companies for their quality of working conditions and interns for their qualities of work This model for internship has been applied for a NGO which is International CBMC (Christian Businessman Committee International)

• Journal of Navigation and Port Research
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• v.38 no.3
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• pp.307-315
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• 2014

This paper aims to empirically examine how shipping companies can effectively acquire knowledge from their strategic alliance partners. This paper adopts cooperative network embeddedness mechanism, such as network density and tie closeness, as a channel through which to acquire more knowledge for shipping participants within a strategic alliance network. This study also examines the moderating role of competition between alliance partners in reinforcing the effectiveness of the cooperative relationships on the knowledge acquisition. Based on the literature, hypotheses to predict the aforementioned associations between cooperative network embeddedness and knowledge acquisition and the moderating role of competition in facilitating that association are established. A quantitative research method using survey data conducted in the Korean shipping industry was employed in order to empirically test the presented hypotheses. The results show that if players in a shipping alliance network are embedded in a dense network and have close relationships with their alliance partners, this helps to facilitate a greater degree of knowledge acquisition from the partners; and the impact of network density on the knowledge acquisition would be intensified with the higher level of competition between shipping companies.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.6
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• pp.83-91
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• 2008

This study grasped problems and properties of rural tourism through Cooperative Tourism Development Model Project, so it provided to develop network program and to indicate long-term development direction. This study area was Gubyung-Areum village in Boeun-gun, Chungcheongbuk-do. This village has superior natural landscape and rich area theme. Also, this village was chosen in Areum Village Revitalization Project in 2002, infrastructure full equipment was achieved. Gubyung-Areum village is administering buckwheat flower festival and experience program by Bo-Eun County Office help to change the farm stay village to the rural experience village. But, there were some problems to operate in experience program. So that Chungcheongbuk-do Provincial Government Republic of Korea is propelling Cooperative Tourism Development Model Project for coping these problems from 2007.12.31 to 2008.9.30. This study is going to develop tourism network program that take advantage of enough area resources grasping problem of Gubyung-Areum village through propulsion of Cooperative Tourism Development Model Project. This study present Developing Strategies for Gubyung-Areum village through investigation, analysis and operation process.

• ETRI Journal
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• v.37 no.2
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• pp.262-272
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• 2015

In particular, for a practical mobile robot team to perform such a task as that of carrying out a search and rescue mission in a disaster area, the network connectivity and localization have to be guaranteed even in an environment where the network infrastructure is destroyed or a Global Positioning System is unavailable. This paper proposes the new collective intelligence network management architecture of multiple mobile robots supporting seamless network connectivity and cooperative localization. The proposed architecture includes a resource manager that makes the robots move around and not disconnect from the network link by considering the strength of the network signal and link quality. The location manager in the architecture supports localizing robots seamlessly by finding the relative locations of the robots as they move from a global outdoor environment to a local indoor position. The proposed schemes assuring network connectivity and localization were validated through numerical simulations and applied to a search and rescue robot team.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4572-4586
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• 2019

Mobile Edge Computing (MEC) and Information-Centric Networking (ICN) are essential network architectures for the future Internet. The advantages of MEC and ICN such as computation and storage capabilities at the edge of the network, in-network caching and named-data communication paradigm can greatly improve the quality of video streaming applications. However, the packet loss in wireless network environments still affects the video streaming performance and the existing loss recovery approaches in ICN does not exploit the capabilities of MEC. This paper proposes a Deep Learning based Loss Recovery Mechanism (DL-LRM) for video streaming over MEC based ICN. Different with existing approaches, the Forward Error Correction (FEC) packets are generated at the edge of the network, which dramatically reduces the workload of core network and backhaul. By monitoring network states, our proposed DL-LRM controls the FEC request rate by deep reinforcement learning algorithm. Considering the characteristics of video streaming and MEC, in this paper we develop content caching detection and fast retransmission algorithm to effectively utilize resources of MEC. Experimental results demonstrate that the DL-LRM is able to adaptively adjust and control the FEC request rate and achieve better video quality than the existing approaches.

• Journal of the Korea Computer Industry Society
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• v.6 no.5
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• pp.775-782
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• 2005

The service of wireless network has problems due to low bandwidth, frequent disconnection, low packet transport and user' mobility. In this paper, we proposed the cooperative methods of update to perform efficiently wireless network services. The proposed method performs the updates by cooperative filtering and streaming by $mbuffer_{in}$ and $mbuffer_{out}$. The simulation results show performance improvement of the proposed method compared to others.

• Journal of Communications and Networks
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• v.14 no.2
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• pp.169-178
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• 2012

In this paper, we study the advantages of using range extension cooperative transmission (CT) in multi-hop energy harvesting wireless sensor networks (EH-WSNs) from the network layer perspective. EH-WSNs rely on harvested energy, and therefore, if a required service is energy-intensive, the network may not be able to support the service successfully. We show that CT networks that utilize both range extension CT and non-CT routing can successfully support services that cannot be supported by non-CT networks. For a two-hop toy network, we show that range extension CT can provide better services than non-CT. Then, we provide a method of determining the supportable services that can be achieved by using optimal non-CT and CT routing protocols for EH-WSNs. Using our method and network simulations, we justify our claim that CT networks can provide better services than nonCT networks in EH-WSNs.