• Journal of KIISE:Computer Systems and Theory
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• v.32 no.9
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• pp.433-444
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• 2005

In video-on-demand(VOD) systems, a broadcast-based scheduling mechanism is known to be a very efficient technique for disseminating popular videos to very large client populations. The main motivations of broadcasting scheduling mechanisms are that they scale up extremely well and they have very modest bandwidth requirements. This paper proposes a new dynamic broadcasting scheduling mechanism, named FDBS (fast dynamic broadcasting scheme), and proves its correctness. This paper also evaluates the performance of FDBS on the basis of a simulation approach. The simulation results indicate that FDBS shows a superior performance over UD, CBHD, and NPB in terms of the average response time with very reasonable bandwidth requirements.

• 한국ITS학회:학술대회논문집
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• 2004.11a
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• pp.375-379
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• 2004

• ETRI Journal
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• v.25 no.4
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• pp.211-218
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• 2003

This paper presents a dynamic resource allocation algorithm with multi-frequency time-division multiple access for the return link of interactive satellite multimedia networks such as digital video broadcasting return channel via satellite systems. The proposed timeslot assignment algorithm, called the very efficient dynamic timeslot assignment (VEDTA) algorithm, gives an optimal assignment plan within a very short period. The optimality and computational efficiency of this algorithm demonstrate that it will be useful in field applications.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.507-510
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• 1999

Data broadcasting service is essential for the widespread deployment of the emerging DTV which can provide various new services, especially program related, computer-like data services. We analyze DVB and ATSC efforts and propose a data broadcasting model which is supposed to be included in Korea DTV specification.

• Journal of Broadcast Engineering
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• v.9 no.4 s.25
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• pp.371-383
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• 2004

In this paper we consider technological requirements to broadcast digital television signals using single frequency networks (SFN) in the Advanced Television Systems Committee (ATSC) transmission systems and propose equalization digital on-channel repeater (EDOCR) that overcomes the limitations of conventional digital on-channel repeaters (DOCRs). Since there are no forward error correction (FEC) decoder and encoder, the EDOCR does not have an ambiguity problem. In addition, since an adaptive equalizer in the EDOCR removes multi-path signals, additive white Gaussian noise (A WGN), and feedback signal due to low antenna isolation, the EDOCR may have good output signal quality with high power.

• IEMEK Journal of Embedded Systems and Applications
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• v.3 no.4
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• pp.229-234
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• 2008

The 'Anytime, Anywhere' services have been the biggest topic in the recent digital broadcasting research area. The related applications for the Anytime and Anywhere Services are as follows: the personalized broadcasting based on the PVR (Personal Video Recorder) for the Anytime Services, and the DMB (Digital Multimedia Broadcasting), the mobile devices supporting the wireless network and the Second TV and so on for the anywhere services. The personalized broadcasting has been researched on the one of the killer applications in the various broadcasting environment - the ground wave broadcasting, the satellite broadcasting, IPTV and CATV broadcasting suchlike. The applied contents of the personalized broadcasting have advanced from the main contents for the broadcasting to the interstitial contents like advertisements and coupons, the personalized interstitial broadcasting needs to develop the technology about the generation, storing and management of the interstitial metadata. but, the personalized broadcasting has the limitation that the TV environment is somewhat difficult to support the personalized broadcasting individually, because all family usually share the main TV at home. The Second TV is possible to solve the environmental limitation. This paper designs and develops the static set top box at home, the Second TV and their multimedia streaming techniques for the personalized broadcasting of the contents including the interstitial contents.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.2
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• pp.339-344
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• 2013

Airport security activities to ensure the airport's facilities and assets from crime, such as theft, to prevent. security systems that support these activities efficiently so you can be called. security center systems, CCTV systems, access control systems, intrusion detection systems, security communication systems, warning broadcasting system, network security systems, perimeter intrusion detection systems, search systems, and information security systems for the security system will be examined.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.977-979
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• 2012

The existing wireless village broadcasting systems use the method to connect to village broadcasting system using wire/wireless telephone to announce the important notices, public relations, and disater status. This type of systems have the problems that if broadcaster is facing rough going or forget the announcement time, it is impossible to inform village people important contents, urgent disaster status, evacuation method. This paper describes internet based village broadcasting system using mobile App to solve these problems. Broadcaster can save the voice and send the voice to App server using the mobile App to activate that voice specific day and time. This mobile App system can improve the efficiency and customer satisfaction of village broadcasting system.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.31-36
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• 2022

Interval caching is one of the representative caching strategies used in multimedia streaming systems. However, there has been no theoretical analysis on interval caching. In this paper, we present an optimality proof of the interval caching policy. Specifically, we propose a caching performance model for multimedia streaming systems and show the optimality of the interval caching policy based on this model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5A
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• pp.484-489
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• 2007

The main disadvantage of orthogonal frequency division multiplexing (OFDM) systems is its sensitivity to carrier frequency offset and timing offset. This paper proposes a simple way of improving the performance of the integer frequency offset (IFO) estimator in OFDM-based digital video broadcasting (DVB) system. By modifying the conventional maximum likelihood (ML) estimator to have multi-stage estimation strategy, IFO estimator is derived. Simulations indicate that the proposed IFO estimator works robustly with reduced computational burden when compared to ML estimator.