• 제목/요약/키워드: shin-huh

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SIP 기반 인터넷 방송 시스템 설계 및 구현 (Design and Implementation of Internet Broadcast System Based on SIP)

  • 배일수;김정기;최일성;김동규;김상미;최선완;허미영;박선옥;강신각
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2002년도 추계학술발표논문집 (중)
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    • pp.1555-1558
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    • 2002
  • 현재 여러 기관에서 사용하고 있는 방송 시스템은 스튜디오, 방송 장비의 설치 및 확장에 대한 불편함과 비용의 부담, 거리에 따른 방송품질의 저하 등 많은 문제점을 가지고 있다. 이를 해결하기 위한 대안으로 인터넷을 이용한 방송 시스템이 등장하였다. 이는 별도의 시스템 추가 없이 인터넷이 연결되어 있는 장치를 이용하므로 비용절감과 설치의 간편함, 일정한 방송품질을 제공할 수 있다. 그러나 현재 소개되어 있는 인터넷을 이용한 방송 시스템들은 독자적 합의에 의한 호 설정으로서, 시스템 확장과 선택에 대하여 매우 낮은 퍼포먼스를 제공한다. 이를 해결하기 위해 차세대 네트워크 서비스로 각광받고 있는 SIP(Session Initiation protocol)을 이용하여 방송 시스템을 설계 및 구현 하였다.

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Laser-Induced Formation and Disintegration of Gold Nanopeanuts and Nanowires

  • Park, Jung-Shin;Yoon, Jun-Hee;Kim, Hyung-Jun;Huh, Young-Duk;Yoon, Sang-Woon
    • Bulletin of the Korean Chemical Society
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    • 제31권4호
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    • pp.819-824
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    • 2010
  • We report the laser-induced formation of peanut-shaped gold nanoparticles (Au nanopeanuts) and gold nanowires (AuNWs), and their morphological properties. Pulsed laser irradiation of citrate-capped gold nanoparticles at 532 nm induces fragmentation, spherical growth, the formation of Au nanopeanuts, and the formation of AuNWs, sequentially. High-resolution transmission electron microscopy images reveal that the Au nanopeanuts are formed by instantaneous fusion of spherical nanoparticles in random orientation by laser heating. Furthermore, Au nanopeanuts are bridged in a linear direction to form AuNWs by an amorphous accumulation of gold atoms in the junction. The laser-produced Au nanopeanuts and AuNWs slowly disintegrate, restoring the spherical shape of the original Au nanoparticles when the laser irradiation is stopped. The addition of citrate effectively prevents them from transforming back to the nanospheres.

Overlap syndrome of Miller-Fisher syndrome/Pharyngeal-Cervical-Brachial variant-Guillain Barre Syndrome with anti-ganglioside complex antibodies

  • Lee, Suk-yoon;Oh, Seong-il;Huh, So-Young;Shin, Kyong Jin;Kim, Jong Kuk;Yoon, Byeol-A
    • Annals of Clinical Neurophysiology
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    • 제22권2호
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    • pp.112-116
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    • 2020
  • Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS) can present with overlapping features. A 56-year-old female developed ptosis and diplopia after an upper respiratory infection, and presented with facial palsy, dysarthria, brachial weakness, ataxia, and areflexia. Mild weakness of both legs appeared after a few days. Anti-ganglioside complex antibody were positive to IgG GM1/GQ1b and GQ1b/sulfatide antibodies. The present case suggests that the manifestation of overlap between MFS/PCB variants and GBS could be caused by antiganglioside complex antibodies.

345kV 승압용 변전소의 뇌격에 의한 이상전압 해석 (Analysis of Transient Voltage by Lightning Stroke at 345kV Step-up Transformer)

  • 조만영;신호전;허재선;김재철
    • 조명전기설비학회논문지
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    • 제26권10호
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    • pp.95-101
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    • 2012
  • Typically, large scale power generation facilities are linked to 345kV transmission line through a step-up transformer. If the value of transient voltage by generating lightning stroke is large more than electric equipment's BIL, devices insulation is destroyed. LA(Lighting Arrester) is used as a main means of prevention. However, the installation of LA takes the constraints of installation place and expensive installation costs. Therefore, we need to carefully study whether installation of installation can be omitted and the most efficient place of installation. In this paper, we simulated the transient voltage detected by lightning stroke at each equipments in the 345kV transmission power grid by using EMTP-RV program.

A Study on Development of Laptop-Based Pilots' Ship-Handling Simulation Software

  • Jeong, Tae-Gwoen;Chen, Chao;Lee, Shin-Geol;Lee, Jeong-Jin;Huh, Yong-Bum
    • 한국항해항만학회지
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    • 제36권7호
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    • pp.571-575
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    • 2012
  • Berthing and unberthing maneuver is essential work for marine pilots and securing the safety against risks during the maneuver is more important than anything else. Moreover, the maneuvering environment in ports and harbors has changed rapidly and got worse due to development of a new port, the advent of a new type or large-sized ship, and the rapid increase in harbor traffic. As one of measures taken to cope with such changes in the maneuvering environment and for each pilot to improve his own maneuvering ability, this paper developed laptop-based ship-handling simulator which is readily available anytime and anywhere. This paper is to develop a conning display for ship's maneuvering and electronic chart based display widely used nowadays to represent a model ship's movement. The displays were arranged appropriately considering pilot age, easy handling by mouse, using a maximum screen, proper arrangement of rudder, engine, thruster, tug etc and representation of information. Up to now thirteen (13) model ships were developed based on real-ship, whose mathematical model is Japanese MMG & pilots' low speed maneuver.

이산형 칼만 필터를 이용한 서보 시스템의 추정자 설계 (Design of an Estimator for Servo Systems using Discrete Kalman Filter)

  • 신두진;허욱열
    • 대한전기학회논문지:전력기술부문A
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    • 제48권8호
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    • pp.996-1003
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    • 1999
  • This paper propose a position-speed controller with an estimator which can estimate states and disturbance. The overall control system consists of two parts: the position-speed controller and an estimator. The Kalman filter applied as state-feedback controller is an optimal state estimator applied to a dynamic system that involves random perturbations and gives a linear, unbiased and minimum error variance recursive algorithm to optimally estimate the unknown state. Therefore, we consider the error problem about the servo system modeling and the measurement noise as a stochastic system and implement a optimal state observer, and enhance the estimate performance of position and speed using that. Using two-degree-of freedom(TDOF) conception, we design the command input response and the closed loop characteristics independently. The servo system is to improve the closed loop characteristics without affecting the command imput response. The characteristics of the closed loop system is improved by suppressing disturbance torque effectively with the disturbance observer using a inverse-transfer matrix. Therefore, the performance of overall position-speed controller is enhanced. Finally, the performance of the proposed controller is exemplified by some simulations and by applying the real servo system.

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인위적으로 발성된 전자파에 의한 반도체 소자의 파괴 효과 (Destruction Effect of Semiconductors by Impact of Artificial Microwave)

  • 홍주일;황선묵;황청호;박신우;허창수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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    • pp.1609-1610
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    • 2006
  • 이 논문은 인위적으로 전자파를 발생시켜 이 전자파에 의한 반도체 소자의 피해 효과를 조사한 것이다. 동작주파수가 2.45 GHz인 마그네트론으로부터 발생되는 전자파는 끝단이 개방되어있는 도파관을 통해 자유공간으로 전파되고, 도파관 끝단으로부터 $30\;cm\;{\sim}\;50\;cm$인 지점에 반도체 소자들을 위치시켜 동작상태를 확인하였다. 시험에 사용된 피시험체인 반도채 소자로는 TTL과 CMOS 기반기술의 반도체를 사용하였고, LED 구동회로를 구성하여 LED의 점등 여부로 오동작 및 파괴 여부를 육안 식별하였다. 또한 시험 전후의 반도체 소자 표면을 제거 후 칩 상태를 SEM 분석하였다. 시험 결과 도파관 끝단으로부터 50 cm, 40 cm 떨어진 지점에 반도체 소자를 위치시키고 도파관 끝단에서 발생되는 전자파에 의한 반도체 소자의 피해는 전혀 없었다. 그러나 30 cm 떨어진 지점에서 오동작 및 파괴가 일어났다. 오동작 및 파괴가 일어난 시료의 칩 상태를 SEM 분석한 결과 칩 내부의 onchipwire의 용융으로 인한 파괴와 bondingwire의 완전파괴를 확인할 수 있었다. 위의 시험 결과는 인위적인 전자파 환경에서 반도체 소자의 결합 기구를 해석하는 기초 자료로 활용되며, 전자 장비들의 전자파 장해에 대한 이해에 도움이 되는 자료로 활용될 수 있을 것이다.

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페트리 네트를 이용한 시퀸스 흐름 제어기 설계 및 구현 (Sequence Flow Controller Design and Implementation Using a Petri net)

  • 김문철;김웅석;허우정;신경봉;조영조;류해영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.1254-1256
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    • 1996
  • Design methods for sequence flow controllers play an important role in industrial automation. To design a flexible, reusable, and maintainable control software has become a key issue nowadays. Petri net has been emerging as an important tool to provide an integrated solution for modeling, analysis, simulation, and control of industrial automated systems recently. This paper describes an international standard of programming languages for programmable logic controllers, IEC 1131-3 SFC( Sequential Function Chart), and the sequence flow control method for an SFC using a Petri net-like model.

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IEC1131-3에 입각한 제어 시스템 설계 프로그램 개발 (Development of Control System Design Program Based on IEC1131-3)

  • 허우정;신경봉;김응석;김문철;박정민;김성태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.1263-1265
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    • 1996
  • IEC1131-3 Specification of Programming Controller is established in 1994 and consists of 3 graphical languages and 2 textual languages. It is used in PLC and small scale controller because of its uniformity and extensibility. This paper describes Soft Logic Designer which is a graphical and textual programming editor for IEC1131-3 programming languages. Soft Logic Designer is developed with Object Orient Language, C++ under Microsoft Windows 95. It has two graphic editors for Sequential Function Chart and Function Block Diagram and one textual editor for Structured Text. Users can efficiently write high-level programs with mouse and menu buttons.

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Inhibition of the Replication of Hepatitis C Virus Replicon with Nuclease-Resistant RNA Aptamers

  • Shin, Kyung-Sook;Lim, Jong-Hoon;Kim, Jung-Hye;Myung, Hee-Joon;Lee, Seong-Wook
    • Journal of Microbiology and Biotechnology
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    • 제16권10호
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    • pp.1634-1639
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    • 2006
  • Hepatitis C virus (HCV)-encoded nonstructural protein 5B (NS5B) possesses RNA-dependent RNA polymerase activity, which is considered essential for viral proliferation. Thus, HCV NS5B is a good therapeutic target protein for the development of anti-HCV agents. In this study, we isolated two different kinds of nuclease-resistant RNA aptamers with 2'-fluoro pyrimidines against the HCV NS5B from a combinatorial RNA library with 40 nucleotide random sequences, using SELEX technology. The isolated RNA aptamers were observed to specifically and avidly bind the HCV NS5B with an apparent $K_d$ of 5 nM and 18 nM, respectively, in contrast with the original RNA library that hardly bound the target protein. Moreover, these aptamers could partially inhibit RNA synthesis of the HCV subgenomic replicon when transfected into Huh-7 hepatoma cell lines. These results suggest that the RNA aptamers selected in vitro could be useful not only as therapeutic agents of HCV infection but also as a powerful tool for the study of the HCV RNA-dependent RNA polymerase mechanism.