• 제목/요약/키워드: macroscopic

검색결과 1,119건 처리시간 0.021초

이동 무선 채널에서 다이버시티와 채널 부호를 사용한 DS/SSMA DPSK 통신 시스템의 성능 분석 (Performance Analysis of DS/SSMA DPSK Communication System with Diversity and Channel Coding in Mobile Radio Environment)

  • 강병권;조병진;황금찬
    • 전자공학회논문지A
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    • 제30A권7호
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    • pp.1-11
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    • 1993
  • The bit error rates of DS/SSMA DPSK system with diversity and FEC channel coding in Rayleigh fading and log-normal shadowing channel are evaluated. Microscopic postdetection diversity and macroscopic selection diversiity are used to mitigate the effects of Rayleigh fading and log-normal shadowing, respectively. The numerical results show that the composite use of diversity and channel coding is very efficient for improving system performance compared to their respective uses.

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Optical Interferometric Characterization of Nonlinear Optical Polymer Thin Films

  • Wu, J.W.
    • 한국진공학회지
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    • 제7권s1호
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    • pp.149-155
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    • 1998
  • The linear electro-optic (EO) effect is one of the second-order nonlinear optical effects existing in a noncentrosymmetric macroscopic system. In a polymer thin film, the noncentrosymmetry is achieved by electric field poling. The magnitude of the linear EO response is determined through the orientational distribution function of hyperpolarizable molecular dipoles. The relation between the linear EO coefficient and the second-order nonlinear optical susceptibility is explained. Three different methods of measuring the linear EO coefficient of a poled nonliner optical polymer thin film are introduced and discussed. All of them make use of the interferometric technique, the difference being in the optical parameters which are interfering.

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SUS416강의 열처리제어를 통한 미세구조특성에 관한 연구 (A Study on Microstructural Characteristics of SUS416 Steel by Controlling Heat Treatment Process)

  • 김홍건;최창용;김진수
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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    • pp.336-340
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    • 2001
  • Theoretical efforts were taken to investigate an optimum heat treatment process in martensitic stainlesssteel. The approach is based on the combination of the interpolation and extrapolation method of a standard heat treatment technology with the principle of quenching and tempering temperature difference. The relationship of macroscopic structure and fracture toughness and ductility as well as the Hardness and strength has been focused to induce a simple rule to apply with feasibility. As a result it was found that the grain size influences to the fracture toughness and ductility significantly.

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테마 인터뷰-마크로젠 서정선 대표

  • 벤처기업협회
    • 벤처다이제스트
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    • 통권50호
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    • pp.10-11
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    • 2004
  • 얼마전 세계 최초로‘아버지 없는 쥐’가 탄생하였다는 뉴스가 세상을 깜짝 놀라게 하였다. 한일 공동 연구팀이 4월 22일 세계적 권위의 과학지 네이처에 논문을 게재하며 알려진 이 소식은 신화에나 나올법한‘난자만을 이용한 처녀생식이 가능하다’는 것을 증명한 과학사의 쾌거였다. 이 성과의 한 주역이 바로 한국 바이오벤처기업의 선두주자 마크로젠이다. 미세한 유전자(gene)를 통해 거시적(Macroscopic) 현상을 연구한다는 뜻의 회사이름 마크로젠(Macrogen)처럼 작은 체구에도 불구하고 당당하게 유전공학계의 거목으로 자리매김한 서정선 대표를 만나본다.

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전자우편기반의 다형성 바이러스에 대한 거시적 관점에서의 대응기법 (Macroscopic Treatment to Polymorphic E-mail Based Viruses)

  • 김철민;이성욱;홍만표
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
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    • pp.419-421
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    • 2003
  • 최근의 많은 바이러스들이 전달매체(Vector)로서 전자우편을 이용하며 탐지를 어렵게 하기 위해 다형화 기법을 사용한다. 현재의 안티 바이러스(Anti-virus) 제품들은 일반적인 바이러스와 전자우편에 의해 전파되는 바이러스에 대한 탐지 방식을 구분하지 않고 있으므로 전자우편 기반의 바이러스 탐지에 적절치 않다[1]. 또한 시그너쳐(signature) 기반의 탐지 방식을 이용하므로 다형성 바이러스를 탐지 할 수 없다. 본 논문에서는 전자우편을 통해 전파되는 바이러스를 대상으로 전자우편의 특성을 이용하되 시그너쳐에 의존하지 않응으로써 다형성 바이러스를 탐지 할 수 있는 기법을 소개한다.

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TRAFFIC FLOW MODELS WITH NONLOCAL LOOKING AHEAD-BEHIND DYNAMICS

  • Lee, Yongki
    • 대한수학회지
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    • 제57권4호
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    • pp.987-1004
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    • 2020
  • Motivated by the traffic flow model with Arrhenius looka-head relaxation dynamics introduced in [25], this paper proposes a traffic flow model with look ahead relaxation-behind intensification by inserting look behind intensification dynamics to the flux. Finite time shock formation conditions in the proposed model with various types of interaction potentials are identified. Several numerical experiments are performed in order to demonstrate the performance of the modified model. It is observed that, comparing to other well-known macroscopic traffic flow models, the model equipped with look ahead relaxation-behind intensification has both enhanced dispersive and smoothing effects.

동적재료모델에 의한 벌크 비정질 금속의 판재성형성에 대한 고찰 (Dynamic Materials Model-Based Study on the Formability of Bulk Metallic Glass Sheets)

  • 방원규;이광석;안상호;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2002년도 춘계학술대회 논문집
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    • pp.173-176
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    • 2002
  • Viscoplastic deformation and sheet forming behavior of multicomponent Zr-based bulk metallic glass alloy has been investigated. From a series of mechanical test results, basic processing maps based on Dynamic Materials Model have been constructed to establish feasible forming conditions. Stamping in laboratory scale was then performed at the various stroke speeds and temperatures using a hydraulic press. Failure in macroscopic level was examined to check the validity of constructed processing maps.

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소의 주근포자충에 관한 연구 -(제 II 보) : 심장, 간장, 신장, 설, 횡격막 및 교근내 주근포자충의 조사연구- (A Study on the Bovine Sarcocystis -(Report II ):A Survey on the Bovine Sarcocystis in the Muscles of Heart, Liver, Kidney, Tongue, Diaphragm and Masseter -)

  • 윤화중;라성안
    • 대한수의사회지
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    • 제24권2호
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    • pp.92-97
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    • 1988
  • One hundred eighteen cattle in the slaughter houses of kyeong ki-do were examined for Sarcocystis cruzi using macroscopic and microscopic method of detection. Sausage-shaped Sarcocystis were detected from the heart, diaphragm, tongue, masseter, liver, kid

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Single Calcium Channels in Rat Superior Cervical Ganglion Neurons

  • Lee, Hye-Kyung;Keith S. Elmslie
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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    • pp.38-38
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    • 2002
  • Whole-cell recordings from adult rat sympathetic neurons demonstrate that calcium current is comprised of at least three types, N, L '||'&'||' R. We are using cell-attached patch recording to identify the single calcium channels that underlie these macroscopic currents. Single channels were resolved the presence of 100 mM Ba$\^$2+/ and l${\mu}$M BayK 8644 over the voltage range -40 to $\^$+/50 mV.(omitted)

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