• Title/Summary/Keyword: constant envelope

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Studies on the Antigenicity and Immunogenicity of Newcastle Disease Virus Inactivated with Binary Ethylenimine (Binary Ethylenimine으로 불활화(不活化)한 Newcastle Disease Virus의 항원성(抗原性)과 면역원성(免疫原性)에 관한 연구(硏究))

  • Park, Bong-kyun;Jeon, Yun-seong;Lee, Young-soon;Rhee, Young-ok
    • Korean Journal of Veterinary Research
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    • v.25 no.2
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    • pp.155-165
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    • 1985
  • Effects of binary ethylenimine (BEI) treatment on the inactivation of infectivity and hemagglutinin of Newcastle disease virus (NDV) were studied in comparison with those of formalin treatment. Immune responses of chickens vaccinated with BEI-inactivated NDV vaccines were also investigated. The results were summarized as followings; 1. Complete loss of infectivity of NDV (Bl) was observed at 3, 7, and 24 hours after the treatment at $37^{\circ}C$ with BEI concentrations of 0.01M, 0.005M and 0.001M, respectively. 2. The hemagglutinin activity of NDV (Bl) remained constant when treated with 0.01M BEI at $37^{\circ}C$. However, it gradually decreased when treated with 0.1% or 0.2% formalin at $37^{\circ}C$. 3. When 4-week-old chickens were vaccinated with NDV vaccines prepared from Bl or Miyadera strains of NDV, inactivated with 0.1M BEI and adsorbed to aluminium hydroxide gel, favorable immune responses were observed throughout the 8 weeks of observation period. 4. When these chickens were revaccinated at 8 weeks after the first vaccination, strong anamnestic responses were evoked and the immunity maintained for 4 weeks of the observation. Though slightly bettor immune responses were observed after primary vaccination in chickens vaccinated with Bl vaccine compared with those vaccinated with Miyadera vaccine, the differences were not significant. 5. On the electron microscopy, BEI (0.01M) gave least effect to the envelope as well as capsid of NDV.

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Multiple-Symbol Differential Detection Scheme of Differentially Encoded MultiPhase Clipped MultiCode CDMA System (차동 부호화된 MultiPhase Clipped MultiCode CDMA 시스템의 수신 성능 개선을 위한 다중 심볼 차동 검출 방식 연구)

  • 이병하;안철용;김동구;조진웅
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10A
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    • pp.807-815
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    • 2003
  • MultiCode-CDMA (MC-CDMA) system of chip level MPSK incorporating with clipper (MP-CDMA)[l] shows constant envelope signal which can mitigate the performance degradation due to nonlinear transmit amplifier. In this paper, modulation is modified to carry out differential encoded MPSK rather than MPSK. The modified system is called DMP-CDMA. DMP-CDMA using differential detection has advantages on receiver complexity and pilot overhead. However, it is inferior to coherent detection by about 4.0dB due to inherent power inefficiency of noncoherent detection and the error propagation. Multiple symbol differential detection is employed in order to improve DMP-CDMA using differential detection. As the result, the performance of DMP-CDMA system is improved about 3.6dB compared to differential detection.

Estimation of Hoek-Brown Constant mi for the Basaltic Intact Rocks in Jeju Island (제주도 현무암의 Hoek-Brown 계수 mi의 추정)

  • Yang, Soon-Bo
    • Journal of the Korean Geotechnical Society
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    • v.36 no.10
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    • pp.21-31
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    • 2020
  • In this study, Hoek-Brown constants (mi) were calculated through nonlinear regression analyses using the results of the triaxial compression tests for the basaltic intact rocks in Jeju Island. The relationships of the mi with the uniaxial compressive strength (UCS), Brazilian tensile strength (BTS) and UCS/BTS of the Jeju basalts were investigated, respectively. In addition, a method that can be used in determining Hoek-Brown failure envelopes including the tensile and compressive failures of the Jeju basalts has been proposed. As results, the mi values had no clear correlations with the UCS, BTS and UCS/BTS of the Jeju basalts, but there were two strong correlations between UCS and mi/UCS, and between BTS and mi/BTS of the Jeju basalts. In addition, it was found that the tensile strengths calculated by the Hoek-Brown failure criterion underestimate the tensile strengths of the Jeju basalts through the relationship between the mi and UCS/BTS of the Jeju basalts. The method presented in this study is considered to be useful in determining the Hoek-Brown failure envelope for the tensile and compressive failures of the Jeju basalts.

L-shaped Slot Antenna for WLAN MIMO Application (무선랜 MIMO용 L-형 슬롯 안테나)

  • Song, Won-Ho;Nam, Ju-Yeol;Lee, Ki-Yong;Lee, Young-soon
    • Journal of Advanced Navigation Technology
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    • v.20 no.4
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    • pp.344-351
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    • 2016
  • In the present study, a dual-band multiple-input-multiple-output (MIMO) antenna covering WLAN frequency bands of 2.4 GHz (2.4 ~ 2.484 GHz) and 5 GHz (5.15 ~ 5.825 GHz) is newly presented to avoid use of decoupling structure for increasing isolation. The antenna consists of two L-shaped slots with n-shaped slots etched on the floating ground plane surrounded by open ended L-shaped slots which are placed in the left and right corner of PCB respectively. The proposed antenna is designed and fabricated on one side of FR4 substrate with dielectric constant of 4.3, thickness of 1.6 mm, and size of $50{\times}50mm2$. It has been observed that the measured impedance bandwidths ($S_{11}{\leq}-10dB$) are 0.3 GHz (2.28 ~ 2.58 GHz) in 2.4 GHz frequency band and 0.89 GHz (5.11 ~ 6 GHz) in 5 GHz frequency band respectively. In addition, It has been observed that the whole efficiency are more than 80 % in the whole operating frequency band and envelope correlation coefficient of the antenna is less than 0.05 as a very small value in spite of nothing of the decoupling structure.