• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2004년도 춘계 종합학술대회 논문집
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• pp.365-371
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• 2004

디지털 기술의 급속한 발전으로 디지털 방송에 대한 여러 가지 요소기술과DTV가 곧 상용화 될 전망이다. 본 연구는 대용량 DVD 저장매체를 이용하여 3D 1-n급 방송 스트림을 송출하기 위한 시스템 설계에 관한 것이다. HD급 방송 스트림을 위한 HDD 및 여러 가지 저장매체를 통해 영상 데이터를 억세스를 하지만 데이터 보관방법상의 문제점과 디스크의 원리상 데이터 억세스를 균일하게 처리하지 못하여 발생하는 인터페이스 동기 불일치 등의 문제점이 있다. 그러므로 DVD 매체를 통한 저장방법 및 억세스의 균일함을 제공하고, 송출 출력을 2.4Mpds 인터페이스 고정시켜 응용 프로그램에서 미디어 정보를 MMIO DMA방식으로 버퍼링하므로써 스트림을 재생할 때 동기 등의 문제점을 해결하였으며, 또한 PCI 컨트롤러는 FPGA VHDR coding하여 PC의 3D-Streamer 응용 프로그램의 명령 신호로 제어를 한다. 이 명령에 따라 3D-Streamer는 3차원 입체영상적인 영상출력을 SMTPE-310M으로 출력하거나 8 DVB 모드로 출력을 하게 된다. 따라서 DVD 전송 직병렬 인터페이스로서 다른 셋톱 장치 및 스트림 전송 장치와 데이터 호환을 이루게 된다.

• 대한전기학회논문지
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• 제32권5호
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• pp.157-163
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• 1983

Positive and negative coronas in point-to-plane short gap have been investigated with the variations of point radius and gap length. Mainly the onset potentials and current pulses under various conditions were measured with a 70 MHz C.R.O. and a precise-controllable D.C. power supply. In the case of negative corona, the Trichel pulse corona, glow corona and spark regions were distinguished apparently and the critical gap lengths between them were also found clearly. In the case of positive corona, there are streamer corona, spark regions and the critical gap length between them, too. The current pulse forms of Trichel pulse corona of negative and streamer pulse corona of positive are similar in rising time, peak-to-peak time and pulse width. The glow corona current shows D.C. component in form.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.137-141
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• 1996

This paper deals with the prebreakdown phenomena of $SF_{6}$ gap stressed by non-oscillating and oscillating impulse voltages in a strong inhomogeneous field disturbed by a fred needle shaped-protrusion on the earth-side electrode. The breakdown voltage-time characteristics were measured for both positive and negative polarities and over the gas pressure range of 0.1∼0.5 MPa, and the temporal developments of the 77breakdown were observed by a shunt of 50 n. The dependence of the leader stopping time on the gas pressure were obtained. The local field enhancement due to the space charges, which is produced by the streamer corona, has influence with the electrical breakdown of the test gap. The test streamer corona is oxy a necessary condition for the electrical breakdown and the subsequent ionization activities launch the leader at the local field region.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2044-2046
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• 1999

In this paper, the propagation of corona streamer was simulated using finite element method(FEM) combined with Flux-Corrected Transport(FCT) algorithm. To obtain more effective grid distribution, the adaptive mesh generation scheme was also employed. The employed adaptive scheme can refine the mesh where needed. In addition, it is possible to coarsen the unnecessarily dense mesh. Two models were analyzed with proposed method. And the results are shown.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.349-352
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• 2007

Estimating the physical properties of the survey area and mapping the geotechnical basement play an important role in ocean engineering and construction field. In this study, we performed marine seismic reflection and refraction survey as an engineering application at shallow marine. We made use of the dual boomer - single channel streamer as a source-receiver in reflection seismic survey and air-gun source - the manufactured OBC(Ocean Bottom Cable)-type streamer in refraction survey. In the seismic reflection data, we could easily find the geological layers and basement. Moreover, seismic refraction data could present sediment thickness and velocity distribution.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권8호
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• pp.384-391
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• 2001

The insulation strength between contacts after current interruption to the transient recovery voltage i.e., the dielectric recovery strength should be estimated for the evaluation of the small capacitive current interruption capability. Many authors have used theoretical and semi-experimental approaches to evaluate the transient breakdown voltage after the current interruption. Moreover, an empirical equation, which is obtained from a series of tests, has been used to estimated the dielectric recovery strength. Un this paper, the theoretical method which is generated from the streamer theory has been applied to real circuit breakers in order to evaluated the interruption capability. The results of analysis have been compared with the test results and the reliability has been investigated.

• Journal of Information Science Theory and Practice
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• 제5권1호
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• pp.65-84
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• 2017

Three most popular information services, Periscope, Ustream, and YouNow, vicarious for all Social Live-Streaming Services (SLSSs), are investigated to analyze their streamers' motivations and the user-generated content. Additionally, we collected demographic data (gender and age). More than 7,500 streams by users from the U.S., Germany, and Japan were observed. Main streamer motivations on SLSSs are boredom, socializing, the need to reach a specific group, the need to communicate, and fun. Important content categories on all three SLSSs are chatting, sharing information, 24/7, and 'slice of life.' We were able to identify differences between users from the U.S., Germany, and Japan as well as between the users of Periscope, Ustream, and YouNow. The main motive to stream in the U.S. is to reach a specific group, while in Japan it is socializing, and in Germany boredom. The top content category for both, YouNow as well as Periscope, is to chat; on Ustream it is 24/7 (i.e., webcams).

• 대한전기학회논문지
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• 제35권1호
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• pp.17-25
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• 1986

Discussions on this paper are related to the effects of organic materials to treeing phenomena of low density polyethylene. As additives, 11 kinds of organic compounds are selected by considering the respective features such as melting point, boiling point, electron affinity as well as molecular structure, and then the specimens of low density polyethylene are prepared by blending with 10wt% of the selected additives. For the comparison of effectiveness of treeing resistance and interpretation of the mechanism of compounds as treeing retardants, several investigations such as the tree acceleration test, the prestressed test and the measurement of internally occurred partial discharge are carried out. As the results, meta-Cresol is regard as the most effective retardant among those, and it is supposed that this aromatic compound to be comprised of radical having large electron affinity has strong capability to accept energetic electron to prevent or delay the growth of discharge streamer. Furthermore, by activating partial discharge at the wall of tree pit through the function of trapped electron at this material, the gas pressure in the pit is increased up to prevent the growth of streamer.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권10호
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• pp.528-533
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• 2006

To analyze the small current interruption performance for the gas circuit breakers, the gas density and electric field intensity should be calculated. In this paper, the FVFLIC method is used for the gas flow analysis and the FEM for the electric field analysis. Then, the dielectric withstanding voltage is evaluated by the empirical formulation or Streamer theory. By comparing the calculated dielectric strength with the test result, it is found that both methods show good prediction capability for the small current interruption performance. Especially, when both methods predict the same interrupting performance, the prediction is in accordance with the experimental result.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.499-501
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• 2022

최신 기술의 발전으로 인한 메타버스의 등장으로 디지털 휴먼이 재유행하기 시작했다. 이를 활용하여 '버추얼 휴먼'이라는 개념을 정의하고 가상 공간에서 활동하던 '버추얼 스트리머'가 현실의 영역을 넘나들며 활동하고 있다. 본 연구에서는 메타버스와 아바타, 버추얼 스트리머, 버추얼 스트리밍에 대한 분석을 통해 과거와 어떤 점이 달라졌는지 파악하고 이와 관련한 시사점을 통해 현재 버추얼 스트리밍에 대한 한계와 방향성을 제시한다.