• 제목/요약/키워드: Hwang Sung-Ha

검색결과 542건 처리시간 0.027초

5-8 GHz 대역 ASK 변조기 MMIC 설계 및 제작 (Design And Implementation Of ASK Modulator MMIC Operating At 5.8 GHz)

  • 장미숙;하영철;허혁;문태정;황성범;송정근;홍창희
    • 한국통신학회논문지
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    • 제26권11B호
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    • pp.1595-1599
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    • 2001
  • 본 논문에서는 ITS 서비스를 위해 개발된 5.8 GHz대역 근거리 전용 무선 통신을 이용한 자동게이트통관시스템의 차량탑재장치(OBE) 구성요소 중 ASK 변조기를 설계 및 제작하였다. 제안된 ASK 변조기는 인접채널간섭을 줄이기 위하여 3 V 단일전압 드레인 제어 변조회로로 설계되었으며 0.7 - 3 V의 넓은 선형변조영역과 40 dB 이상의 On/off Ratio 특성을 얻었다. 회로의 Layout과 공정은 ETRI 0.5$\mu\textrm{m}$ MESFET Library를 사용하였고 칩 면적은 1.0mm $\times$ 1.0mmn로 제작하였다.

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HIGH TEMPERATURE SUPERCONDUCTING THIN FILMS PREP ARED BY PULSED LASER DEPOSITION

  • Park, Yong-Ki;Kim, In-Seon;Ha, Dong-Han;Hwang, Doo-Sup;Huh, Yun-Sung;Park, Jong-Chul
    • 한국표면공학회지
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    • 제29권5호
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    • pp.430-436
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    • 1996
  • We have grown superconducting thin films on various substrates using a pulsed laser deposition (PLD) method. $YBa_2Cu_3O_7-\delta$ (YBCO) superconducting thin films with the superconducting transition temperature ($T_{c. offset}$) of 87K were grown on Si substrates using yittria-stabilized zirconia (YSZ) and $CeO_2$ double buffer layers. We have developed a large area pulsed laser deposition system. The system was designed to deposit up to 6 different materials on a large area substrate up to 7.5cm in diameter without breaking a vacuum. The preliminary runs of the deposition of YBCO superconducting thin films on $SrTiO_3$ substrate using this system showed a very uniform thickness profile over the entire substrate holder area. $T_{c}$ of the deposited YBCO thin film, however, was scattered depending on the position and the highest value was 85K.

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2중 공극형 횡자속 영구자석 동기발전기 설계 및 특성분석 (Design and Characteristics Analysis of Dual Air-Gap Axial-Flux type Permanent-Magnet Synchronous Generator)

  • 배성우;황돈하;강도현;김용주;최경호;김동희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1063-1066
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    • 2003
  • This paper presents the design and characteristics analysis of axial-flux permanent-magnet (PM) synchronous generator of two air-gap. Dual axial-flux type PM synchronous generator commonly appears in applications where the generator axial dimension is more limited than the radial dimension. The strengths of dual axial-flux generator include ; (1) by employing two air-gaps, the rotor-stator attractive forces are balanced and no net axial or thrust load appeals on the generator hearings ; (2) heat produced by the stator windings appears on the outside of the generator, making it relatively easy to remove, and so on. In this paper, the simple magnetic equivalent circuit approach is used for initial design iteration, and the finite-element method is applied to analyze the detailed characteristics. The test results of driving characteristics are presented as well. The results are very similar to predicted performance of design.

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Immunological Assays of Freezing Tolerance in Barley using Antifreeze Proteins Antisera

  • Sung, Ha-Chang;Kim, Dae-In;Hwang, Cheol-Ho
    • 한국작물학회지
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    • 제48권5호
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    • pp.407-412
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    • 2003
  • In order to measure an antifreezing tolerance, antifreeze proteins accumulated upon cold acclimation in apoplast were analyzed. As Dongborilho were cold-acclimated for 3 to 74 days there was an abrupt increase in apoplastic proteins up to 30 days and then decrease to the similar levels. Among the known antifreeze proteins, CLP produced in E. coli. and TLP purified from apoplast were used to generate antisera that allow to measure and localize the proteins in leaves of barley. The CLP of 27.7 kDa and TLPs of 6, 26, 27, 30, and 31 kDa were increased in their amounts in apoplast as cold treatment being longer. There was a correlation among the amounts of those proteins accumulated in apoplast and freezing tolerance as shown in field and ion leakage tests for five cultivars. The deposit of CLP was localized in the marginal area and the area adjacent to leaf vescular bundle cells in an increasing manner according to duration of cold acclimation but no variation was observed in terms of it's distribution. Based on the close correlation between levels of antifreeze proteins and degrees of freezing tolerance, the immunological methods was to develop to estimate a freezing tolerance in barley.

외부투입형 선박 파공 봉쇄장치의 봉쇄패드에 대한 성능 실험적 연구 (Experimental Study on the Performance of Leak Stopping Pad of Outboard type Leak Stopping System Against the Damaged Hole in the Ship Hull)

  • 나용현;박미연;홍영진;지성철;황종하;이현철
    • 한국재난정보학회:학술대회논문집
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    • 한국재난정보학회 2017년 정기학술대회
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    • pp.331-332
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    • 2017
  • 본 논문에서는 선박간의 충돌이나, 항구시설과의 충돌 등으로 선체에 파공이 발생하여 선박내부에 저장되어 있던 해수 및 오염물질이 해양으로 유출되는 해양 재난상황에서 원격제어 방식으로 파공봉쇄장치가 선체 외벽에 부착 이동을 통해 파공부에 접근하여 파공을 봉쇄할 수 있는 장치를 개발하고 성능을 실험적으로 연구 하였다. 이러한 장치는 인력투입이 불가능한 상황에 신속한 초동 조치를 취할 수 있으며 인력으로 불가능한 압력으로 유출되는 상황에서도 봉쇄가 가능한 장치로 개발하였다. 본 연구를 통해 파공부를 직접적으로 봉쇄하는 장치인 봉쇄 패드의 성능시험의 결과 직경 150mm 파공에서 유출압 0.1~0.75bar의 상황에서 안정적인 봉쇄성능을 실험적으로 검증하였다. 또한 봉쇄패드가 결합된 통합방재로봇인 외부 투입형 선박파공 봉쇄 장치를 원격제어하여 0.1 bar의 압력에서 봉쇄 성능 시험을 성공하였다.

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도심환경에서의 밀결합 측위 기법 (Closely Coupled Positioning Technique in Urban Environments)

  • 황유민;오주영;김윤현;김진영;김하성;지규인
    • 한국위성정보통신학회논문지
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    • 제7권2호
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    • pp.104-109
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    • 2012
  • 최근 위치해를 얻기위해서 위성을 기반으로한 GPS(Global Positioning System) 가 많이 이용되고 있다. 그러나 도심지역 등에서는 다중경로에 의한 영향으로 신뢰성 낮은 위치 정보를 수신할 수도 있다. 이러한 문제점을 해결하기 위해 GPS신호와 QZSS(Quasi-Zenith Satellite System) 신호를 통합하는 밀결합 측위기법을 제안하고자 한다. 또한 AP(access point)정보를 이용함으로써 Wi-Fi 신호와 GNSS신호를 통합하는 밀결합 알고리즘을 제안하고자 한다. 본 연구과제는 도심지역에서 항법성능을 향상시키기 위해서 GPS/QZSS/Wi-Fi 통합항법 알고리즘을 개발하고, 이를 차량주행실험을 통하여 위치의 가용성과 정확도를 기준으로 성능분석을 수행하였다.

토양오염 및 훼손 통합관리를 위한 정책방향 설정 (Establishing Policies towards Integrated Management of Soil Pollution and Damage)

  • 김종성;박윤식;이기하;황상일;양재의
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제22권6호
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    • pp.85-93
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    • 2017
  • In this study, the concepts of soil degradation, soil pollution and soil damage are defined, and the domestic and foreign administrative systems related to soil pollution and soil damage management are analyzed. In case of foreign countries, laws and regulations on the soil conservation and soil damage management were analyzed. In case of Korea, the present state of the legal system governing soil pollution and damage management was analyzed in each aspect. Through this study, suggestions for amendments of relevant laws were proposed by establishing policy direction for integrated management of soil pollution and soil damage. The results of this study will provide a basis for integrated management of soil pollution and damage, and it can be utilized in establishing integrated management strategy of long term soil conservation and sustaninable soil development at national level.

가미귀비탕이 환경호르몬(p, p-DDE)에 의한 발기부전 및 염산 Apomorpine의 penile erection에 미치는 영향 (Effect of Gamigyuibi-tang on the Penile Erection Induced by Apomorphine Hel and Erectic Dysfunction Induced by p,p-DDE)

  • 황주민;강동윤;변성희;김은하;김상찬
    • 동의생리병리학회지
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    • 제17권4호
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    • pp.980-990
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    • 2003
  • The effect of Gamigyuibi-tang on the penile erection induced by apomorphine HCI and on the erectile dysfunction induced by p,p-DDE, an environmental hormone derivate of DOT, were monitored using male cats. The changes of penile length, diameter, erectic periods and histological profiles of corpus cavernosum and corpus spongiosum were observed with blood testosterone levels. In conclusion, dose-dependent and significant increase of penile length, diameter, erectic periods and blood testosterone levels were detected in the Gamigyuibitang-dosing groups compared to other groups. In addition, it is also demonstrated that the increasement of congestion of blood vessels and dilation of connective tissues, and decreasement of adipocytes in the corpus cavernosum and/or corpus spongiosum of the Gamigyuibitang-dosing groups. According to these results, it is considered that Gamigyuibitang has some augmentation effect against to apomorphine HCI inducing penile erection and it also suggested that Gamigyuibitang has favorable effect to treatment of erectic dysfunctions induced by p,p-DDE.

지능형 추천시스템 개발을 위한 지식분류, 연결 및 통합 방법에 관한 연구 (Knowledge Classification and Demand Articulation & Integration Methods for Intelligent Recommendation System)

  • 하성도;황인식;권미수
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.440-443
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    • 2005
  • The wide spread of internet business recently necessitates recommendation systems which can recommend the most suitable product fur customer demands. Currently the recommendation systems use content-based filtering and/or collaborative filtering methods, which are unable both to explain the reason for the recommendation and to reflect constantly changing requirements of the users. These methods guarantee good efficiency only if there is a lot of information about users. This paper proposes an algorithm called 'demand articulate & integration' which can perceive user's continuously varying intents and recommend proper contents. A method of knowledge classification which can be applicable to this algorithm is also developed in order to disassemble knowledge into basic units and articulate indices. The algorithm provides recommendation outputs that are close to expert's opinion through the tracing of articulate index. As a case study, a knowledge base for heritage information is constructed with the expert guide's knowledge. An intelligent recommendation system that can guide heritage tour as good as the expert guider is developed.

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자체 바이어스를 갖는 Folded Cascode OP Amp를 사용한 Single Pixel Photon Counter 설계 (Design of a single-pixel photon counter using a self-biased folded cascode operational amplifier)

  • 장지혜;황윤금;강민철;전성채;허영;하판봉;김영희
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2009년도 춘계학술대회
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    • pp.678-681
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    • 2009
  • 본 논문에서는 자체 바이어스가 되는 Folded Cascode CMOS OP Amp를 이용하여 싱글 픽셀 포톤 계수기 회로를 설계하였다. 전압 바이어스 회로가 필요 없으므로 싱글 픽셀의 레이아웃 면적을 줄이고 전류 소모를 줄일 수 있다. 매그나칩 반도체 $0.18{\mu}m$ CMOS 공정을 이용하여 설계된 CSA(Charge Sensitive Amplifier)의 신호 전압은 이론치인 151mV이 근접한 138mV로 simulation되었다. 그리고 싱글 픽셀의 레이아웃 크기는 $100{\mu}m{\times}100{\mu}m$이다.

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