• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5A
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• pp.475-483
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• 2007

Recently, consumers demand high-quality wireless multimedia services via terrestrial and satellite network. And the interest for new services to sustain its successful commercial deployment grows tremendously. So, the MIMO schemes, such as STCs, MRC, has been used for realizing high reliability. However, MIMO schemes has some limitations. MIMO scheme needs more size, cost, and hardware complexity to employ additional antennas. Moreover, sufficient spaces between antennas are required to guarantee the independence of each channel and the devices which use multiple antennas should be enlarged. A cooperative transmission technique which is detect and forward type applying virtual MIMO with STBC matrix in DVB-RCT(Digital Video Broadcasting with Return Channel via Terrestrial) system based on OFDMA is also proposed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.4
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• pp.39-45
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• 2009

In this paper, designed and fabricated the microstrip antenna using parasitic plane. This active antenna for the use of AM/FM, DMB(Digital Multimedia Broadcasting), GPS(Global Positioning System) band in vehicle. Fabricated active antenna was compared to existing planar antenna represents more than 15% size reduction and equivalence performance compared to commercial helical antenna. And satisfy performance in DMB, GPS band. This active antenna composed of single input port and two output ports and entire size of antenna is $133{\times}31{\times}1.2mm$.

• Journal of the Korea Society of Computer and Information
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• v.4 no.2
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• pp.80-87
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• 1999

We propose the various Telemedicine applications using collaborative PACS environment. Traditionally, almost all medical images have been printed on radiological films. These films are expensive to produce and easy to misplace and usually only one copy exists, thus limiting the number of persons who have simultaneous access to the images. But the merit of this system including PACS(Picture Archiving and Communications System ) is very many which are small depository, low maintenance expense, good efficience(storage, speed) and good flexibility but the development costs is higher. This research has been done creating multimedia-based Telemedicine system for home PCs in network environment. Most of Telemedicine used hardware and exclusive line of high cost as CATV broadcasting technique. But this system will contribute to change the Home-PC for better use of collaborations among doctor and patients through various modes of interactions in cyberspace.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11B
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• pp.722-729
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• 2005

Ethernet passive optical networks (EPONs) are an emerging access network technology which has a point-to-multipoint topology. EPONs operate point-to-multipoint in the OLT-ONU direction, and point-to-point in the ONU-OLT direction. To support point-to-point emulation and shared LAM emulation, EPONs use multi-point control protocol (MPCP). The MPCP uses logical link identification (LLID) field for frame tagging and filtering between the OLT and ONUs. In this paper, I propose logical-group identification (LGID) for logical link-based multicasting or VLAN services in EPONs. Using LGID with new frame tagging and filtering rules, EPONs support differentiated multimedia broadcasting or multicasting services. Additionally, EPONs can support logical link-based VLAN services that divides ONUs into several subsets.

• Proceedings of the Korea Database Society Conference
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• 2010.06a
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• pp.267-275
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• 2010

최근 모바일 기술이 지속적으로 발전해 감에 따라 모바일 통신 네트워크를 통한 방송서비스인 모바일 TV가 급속한 확산을 보이고 있다. 기존 모바일 TV 서비스를 대상으로 수행한 선행연구는 주로 모바일 TV 서비스 관련 기술 탐색, 최신 시장동향 분석, 서비스 수용 영향요인 등을 중심으로 연구가 활발히 진행되어 온 반면 서비스 수용 후 행동에 관하여 체계적인 분석을 수행한 연구는 부족한 것이 현실이다. 이러한 배경 하에서, 본 연구는 모바일 TV 서비스 이용자를 대상으로 해당 서비스에 대한 지속적 이용의도 형성에 중요한 영향을 미칠 것으로 예상되는 요인을 파악해 보는 것을 주목적으로 하였다. 연구목적을 효과적으로 달성하기 위하여 본 연구에서는 관련 문헌에 관한 종합적 고찰을 통해 모바일 TV 서비스의 채택 후 행동을 체계적으로 파악해 보기 위하여 지각된 놀이성, 기대 일치, 지각된 사용용이성, 지각된 유용성, 만족, 지속 이용 의도 등 여섯 가지 차원을 포함한 연구모델을 제안하였다. 그리고 제안된 연구모델에 포함된 각 요인들 간의 영향관계에 관한 연구가설을 수립하였다. 향후 모바일 TV 이용자를 대상으로 설문조사를 수행하고, 제안된 모델 및 가설에 대한 실증적 분석을 실시해 보고자 한다. 본 연구의 결과를 토대로 최근 사용자 수가 급증하고 있으며, 높은 관심의 대상이 되고 있는 모바일 TV 분야의 연구자 및 실무자들에게 서비스 이용자를 장기적으로 유지하고, 이를 토대로 지속적인 수익을 창출하는데 도움을 줄 수 있는 시사점을 제공해 보고자 한다.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.225-227
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• 2009

International standard specification, H.264/SVC improved from H.264/AVC, is set up so as to promote free use of huge multimedia data in various channel environments.;H.264/AVC is a international standard speicification for video compression, adopted and commercialized as standard for DMB broadcasting by JVT of ISO/IEC MPEG and ITU-T VCEG. SVC standard uses 'intra/inter prediction' in AVC as well as 'inter-layer intra prediction', 'inter-layer motion prediction' and 'inter-layer residual prediction' to improve efficiency of encoding. Among prediction technologies, 'inter-layer intra prediction' is to use co-located block of up sampled sublevels as a prediction signal. At this time, application of interpolation is one of the most important factors to determine encoding efficiency. SVC's currently using poly-phase FIR filter of 4-tap and 2-tap respectively to luma components. This paper is written for the purpose of analyzing encoding performance according to the interpolation. For this purpose, we applied poly-phase FIR filter of '2-tap', '4-tap' and '6-tap' respectively to luma components and then measured bit-rate, PNSR and running time of interpolation filter. We're expecting that the analysis results of this paper will be utilized for effective application of interpolation filter. SVC standard uses 'intra/inter prediction' in AVC as well as 'inter-layer intra prediction', 'inter-layer motion prediction' and 'inter-layer residual prediction' to improve efficiency of encoding.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.177-178
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• 2008

지상파 방송(DMB: Digital Multimedia Broadcasting)은 음성, 영상, 데이터와 같은 다양한 멀티미디어 신호를 디지털 방식으로 변조하여 이동 중에 방송을 청취할 수 있는 차세대 디지털방송 서비스이다. 그러나 지상파 DMB 전송 고도화망에서는 계층 변조(Hierarchical Modulation)전송 기법을 통하여 추가의 전송대역폭을 확보할 수 있다. 또한 스케일러블 비디오 코딩(Scalable Video Coding)부호화 방식을 이용하여 고전송효율/고품질의 이동 멀티미디어 방송서비스를 제공할 수 있는 고품질 AT(Advanced Terrestrial)-DMB 시스템이 가능하다. 이러한 고품질 AT-DMB의 개발에 있어서 여러 방식들이 제시됨에 따라 시뮬레이터를 통한 다중화 시스템의 분석이 필요하다. 본 논문에서는 고품질 AT-DMB가 가능한 스케일러블 비디오 방식을 JSVM8.8을 사용하여 구현하였으며, 다중화 시스템의 실험을 하였다. 또한 시뮬레이터를 통하여 복호된 계층 간의 화질 차이와 엔지니어를 위해 비트스트림의 분석화면 및 PSNR을 제공 하였다.

• Journal of IKEEE
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• v.2 no.2 s.3
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• pp.225-232
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• 1998

Currently NTSC, PAL, and SECOM are widely used for TV broadcasting systems. In Korea, NTSC has been used to reduce transmission bandwidth and broadband flickers using the Interlaced scanning method. Image data in the Interlaced scanning method require De-interlacing compensation for PC-based multimedia applications. The existing compensation algorithms such as ZOI, FOI, and ELA provieds simple computations and effective image compensation while the PSNR is low and horizontal and vertical edges are hardly detected. In this paper, the ADI(Adaptive De-Interlacing) algorithm that can increase PSNR and detect horizontal and vertical edges is proposed and a hardware system is implemented using three ACTEL 1020B FPGA chips. The system consists of the algorithm part implemented using two FPGAs and the memory control part implemented using rest one. Also the system operation is investigated for real time processing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.3 s.94
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• pp.270-276
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• 2005

This paper presents an analytical analysis about neighboring UWB interferences in a S-DMB receiver. We first derive the C/N$_{o}$ of a S-DMB receiver, based on its specifications and present the theoretical description of its effect to UWB interferences in terms of C/(N$_{o}$+ I) and I/N$_{o}$. Using the calculated C/(N$_{o}$+ I) and I/N$_{o}$, we derive the separation distance for a S-DMB receiver not to be interfered by UWB interferences. Finally, we propose an UWB emission limit at minimum separation distance under which a S-DMB is free of UWB interferences and compare it with the value appeared in FCC proposal.

• Journal of the Korean Society of Costume
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• v.57 no.1 s.110
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• pp.176-186
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• 2007

The purpose of this study is to reconstruct upper class women's costume of 'Mongol-pung' and 'Goryeo-yang' in a civilization-exchanged period between Mongolia and Korea, for making movie or soap opera costume and historical animation. 'Mongol-pung' was a cultural influence from Mogolia to Korea. For example, sleeveless bi-gap(比甲) and half-sleeved dap-ho(搭忽) were put on by many women at that time. On the basis of old literature, I suggest a 'Mongol-pung' costume as a set of seeran-chulrik(膝欄 terlig), em-broidered bigap, dapho of meat-red color for women. 'Goryeo-yang' was a cultural influence from Korea to Mongolia. Due to old poem of Yuan, 'Short outer Jacket with square neckline, half sleeves, and clear color(方領過腰半臂)' was a representative of 'Goryeo-yang' in Mongolian royal women's costumes. Many women were dressed in it with short inner jacket and wide skirt. In the case of making soap opera costume, the budget of broadcasting station, appearence of nowaday's actor and actress, similarity between old fabric and modern fabric must be considered altogether.