• Journal of the Korea Computer Industry Society
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• v.3 no.7
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• pp.881-890
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• 2002

In this paper, by using agent technology, we proposes and implements the search system that supplies the result close to the user preference through the analysis of user preference. To offer better qualified information to user without redundant search results and unnecessary information of legacy search system. this system uses user's information and generates keywords and categories. Comparing user's favorite category with search result of legacy search system through the agent oriented search engine, it supplies only the result close to the user's category. At the same time, search result is saved into the databases according to each category to be used for search work later. As a result, the redundant information of search result was efficiently removed and the information close to the user's favorite category was obtained.

• Journal of Internet Computing and Services
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• v.12 no.6
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• pp.129-137
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• 2011

In this paper, a fast and reliable emergency broadcasting system for Advanced Television System Committee (ATSC) Mobile DTV is proposed. The proposed protocol is based on the Emergency Alert Message (EAM) standard currently used for cable TV emergency broadcasting in the United States. The protocol is implemented and evaluated to enable fast emergency information propagation. ATSC Mobile DTV enables digital mobile broadcasting without affecting the existing ATSC legacy digital TV system. Since ATSC Mobile DTV devices are mobile and self-powered, they can effectively propagate emergency information. The proposed emergency broadcasting protocol can be applied in all countries adopting the ATSC standard.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.877-887
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• 2015

In this paper, a design of communication joint tools to implement a legacy-line communication (LLC) system, which exploits various conductive lines in a train, is presented. We develop two kinds of joint tools; one is a conductive joint tool (CJT) that is connected directly to the conventional lines and the other is the inductive joint tool (IJT) which connects the conventional lines indirectly using electromagnetic induction. As a result, the practical experiment of data communication confirms that an LLC system with the developed joint tools has a transmission rate more than 20 Mbps in the distance of 200 m away. In addition, an environmental durability test shows that the joint tools operate stably in an extreme environmenal variation. It is, therefore, considered that the developed joint tools are very useful to implement a communication network in the train working currently.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.1
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• pp.127-133
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• 2009

It has been 10 years long since the emergence of Dialpad, the first commercial VoIP service from Saerome Technology launched on 1999. In spite of so many research papers and implementations of the VoIP and commercial services with hundreds of VoIP-related products vendors and tens of VoIP service providers during the last decade, the resulting market share of the VoIP callings at the year 2007 in Korea is just about 0.3%, which is extraordinary lower one than expected. There have been proposed several facts for the reason including the QoS issue and the incomplete governing system. In this paper we suggest that the reason is based on the sociocultural issue and further we assert and verify that it can never replace the existing legacy telephone system for the current VoIP service model, as long as the telecommunication companies continue the legacy telephone service. We also suggest the another choice, to upgrade the concept of the current VoIP service to a new paradigm based on SIP and presence service, while letting the legacy telephone system be as it is.

• The Journal of the Acoustical Society of Korea
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• v.24 no.4
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• pp.186-193
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• 2005

The Terrestrial Digital Multimedia Broadcasting (T-DMB) system supplies high quality audio comparable with VCD in 7 inch display and high quality audio comparable CD at the mobile reception environment T-DMB will launch commercial service at the middle of 2005. However the bandwidth for audio data and the number of channels are restricted to 128 kbps and 2 respectively in the current T-DMB standard because of the limitation of available bandwidth for multimedia data. This Paper Proposes a novel media processor structure for providing multi-channel audio contents oyer T-DMB system allowing backward compatibility with the legacy T-DMB receiver. Furthermore. we also Propose an adaptive receiver structure to supply optimal audio contents on various speaker configuration in T-DMB receiver. To provide multi-channel audio contents allowing backward comaptilbity with the legacy T-DMB receiver, the additional data for multi-channel audio are defined as a dependent stream of main audio stream. The OD strucure for control an additional multi-channel audio elementary stream is proposed without changing the BIFS of the legacy T-DMB system.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.2
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• pp.339-346
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• 2013

As the need for security of SCADA systems is increasing, significant progress has been made in research on security of control protocol. However, very few security solutions were adapted to legacy SCADA system. The reasons for non-adoption are latency, cost and key management problem. We propose a low latency, economic security Solution to solve these issues. The proposed solution performs security function in data link layer and has minimum overhead to minimize latency. Furthermore, we try to solve the key management problem by providing systematic security keys and key distribution method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.10
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• pp.593-600
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• 2014

OFDMA systems solves frequency selective fading problem and provides improved performance by optimal allocation of subcarriers and transmit power. Two-way relay systems provide improved spectral efficiency compared to that of the conventional half-duplex relay using bidirectional communications. In legacy OFDMA system such as WiBro, two-way DF relay utilization causes pilot re-assignment and impossibility of channel estimation and decoding at relay nodes by self-interference. In this paper, resource allocation schemes for legacy OFDMA systems with two-way DF relay are proposed. The proposed schemes allocate subcarriers considering destinations nodes which are connected to relay nodes as individual nodes which are directly connected to a base station. Subsequently, the proposed schemes compensate bandwidth loss due to orthogonal allocations by overlapped allocating unused subcarriers at other noes. Numerical simulations show that the proposed resource allocation schemes provide improved performance compared with orthogonal allocation.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.613-621
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• 2016

This research connected network equipment, including CCTV, PAGA, IP-PBX, and Legacy, in order to enable the operation and configuration of internal IP-based network equipment in maritime plants and vessels, both in the field and from remote places, and to allow for the support of remotely controlling such equipment. It also realized an operating program for the integrated network equipment management system to enable the monitoring and control of equipment status, operation condition, and notifications from distant places. By applying the operating program to satellite stations and vessels sailing on the sea, a performance test was conducted to evaluate data loss and transmission/reception delay in the communication section between the land and vessels. As a result, this research verified the normal operation of CCTV control and of real-time monitoring and control of the network equipment, including PAGA, IP-PBX, and Legacy under the FBB and MVSAT environments. It was observed that the transmission of CCTV video images with a large volume of data as well as the transmission and reception of voice data were found to be slightly delayed, indicating the need to develop technology to compress and convert data for real-time transmission and reception.

• STI Policy Review
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• v.2 no.2
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• pp.11-24
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• 2011

S&T policy has been traditionally regarded as a sector policy; however, it is now evolving into an infrastructure innovation policy that forms the foundation of diverse types of policies. Simultaneously, environmental and energy policies formerly considered as sector policies are now being expanded and integrated into a higher level policy for sustainable development. With these changes underway, the importance of policy integration has increased. Efforts are being made to minimize contradictions between environmental, social, and innovation policies that emphasize proactive linkage among policies or place the highest priority on environmental policy following the theory of Environmental Policy Integration (EPI). Confronted with these policy changes, the Lee Myung-bak government announced "Low-Carbon Green Growth" in 2008 as national agenda for development that focus attention on environmental and energy issues. Economic policy and environmental policy have been traditionally seen in a conflicting relationship with different paths of policy development. However, the administration of President Lee is now emphasizing the synergy effects between the environment and economic growth with the concept of green growth. The green growth policy of the Korean government has great significance as it has built a momentum for incorporating social goals such as environmental values or sustainable development into economic growth-oriented policies; however, there remain many challenges due to the legacy of the development period that has dominated Korean society. The Korean government says it reflects "EPI" or "environmentalism" in policy goals; however, in reality it prioritizes development over the environment.

• Journal of Internet Computing and Services
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• v.2 no.5
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• pp.81-91
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• 2001

XML is a standard markup language for exchange and storage of formed or well-formed information in World Wide Web, Because the source data of XML message for exchange of information in World Woo Web Is stored in legacy database systems. it is necessary the easier connection between XML application and database systems, In Oracle8i. 9i. informix and SQL2000. DBMS vendors extend their DBMSs for XML. This approach for the connection between XML application and database system is Platform-dependent and DBMS-dependent. Therefore it is necessary the platform- and DBMS-independent approach for the connection between XML application and database system, In this paper. we modeled a set of middleware components for relational database design based on XML DTD is modeled, Those components are modeled on object-based algorithm for connection between XML application and database system.