• Title/Summary/Keyword: B125

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A Perturbation Based Method for Variational Inequality over Convex Polyhedral

  • Park, Koo-Hyun
    • Journal of the Korean Operations Research and Management Science Society
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    • v.20 no.2
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    • pp.125-137
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    • 1995
  • This paper provides a locally convergent algorithm and a globally convergent algorithm for a variational inequality problem over convex polyhedral. The algorithm are based on the B (ouligand)-differentiability of the solution of a nonsmooth equation derived from the variational in-equality problem. Convergences of the algorithms are achieved by the results of Pang[3].

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Preparation and Luminescent Properties of YNbO$_4$ : Bi Phosphors by Flux Technique with B$_2$O$_3$ (Boron Oxide Flux를 이용한 YNbO$_4$ : Bi 청색 형광체의 제조 및 발광 특성)

  • 한정화;김현정;박희동
    • Journal of the Korean Ceramic Society
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    • v.36 no.3
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    • pp.319-324
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    • 1999
  • 기존의 고상 반응법에 의해 합성된 YNbO4 : Bi 형광체의 발광특성을 개선하기 위하여 B2O3 융체 첨가법으로 형광체를 합성하고, 빛발광(PL) 및 저전압 음극선발광(CL)을 측정하였다. PL 및 CL 모두 415~440 nm 영역에서 강한 청색 발광 스펙트럼을 나타냈으며, 고상 반응의 경우와 마찬가지로 Y/Nb 비율이 화학 양론상의 1:1인 경우보다 결함구조를 인위적으로 조절한 51/49나 54/46에서 최대의 발광강도를 보였다. 한편, 고상 반응에서는 125$0^{\circ}C$에서 4시간 열처리하는 것이 최대의 발광효과를 나타냈으나, B2O3융제를 첨가하고 110$0^{\circ}C$에서 열처리한 시료가 결정성이 좋고 입자의 크기 및 형태가 균일하여 PL뿐만 아니라 CL에서도 우수한 발광특성을 보였다. B2O3융제를 첨가하는 방법으로 열처리 온도를 낮추고 입자크기와 형태를 조절하여 형광체의 휘도를 개선할 수 있었다.

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Cell transformation of bisphenol A in Syrian hamster embryo cells and mouse embryo BalB/c 3T3 cells (Syrian hamster embryo 세포와 mouse embryo BalB/c 3T3 세포에서의 bisphenol A의 세포 형질전환 연구)

  • 김종원;한의식;박미선;엄미옥;전혜승;민수진;김인숙;정해관;심웅섭
    • Environmental Mutagens and Carcinogens
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    • v.21 no.1
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    • pp.44-50
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    • 2001
  • To identify nongenotoxic carcinogen determined as negative by ICH guideline-recommended standard genotoxicity test battery; Ames test, chromosome aberration assay, mouse lymphoma $tk^{+/-}$ assay, in vivo micronucleus assay, we picked bisphenol A as a model compound. In this study, we applied in vitro BalB/c 3T3 cell transformation assay and Syrian hamster embryo (SHE) cell transfarmation assay. Bisphenol A was treated upto $769.2 ug/m{\ell}$ in BalB/c 3T3 cells and upto $125 ug/m{\ell}$ in SHE cells. bisphenol A didn't induced morphological transformation both with one stage treatment protocol and with two stage treatment protocol. But, treated far 48 hr, Bisphenol A induced morphological transformation significantly in SHE cells.

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Concanamycin B, Active substance Against Phytophthora capsici Produced by Streptomyces neyagawaensis 38D10 Strain (Streptomyces neyagawaensis 38D10 균주가 생산하는 concanamycin B의 항고추역병 활성)

  • Kim, Chang-Jin;Lee, In-Kyoung;Yun, Bong-Sik;Yoo, Ick-Dong
    • Microbiology and Biotechnology Letters
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    • v.21 no.4
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    • pp.322-328
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    • 1993
  • During the screening of antifungal compounds from microbial secondary metabolites to control phytophthora blight of red pepper caused by Phytophthora capsici, a soil isolate, strain 38D10 was selected. Based on taxonomic studies, this strain was identified as Streptomyces neyagawaensis. The antifungal compound was purified from culture broth by HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, HPLC and identified as concanamycin B by UV. $^1H$-NMR, $^{13}C$-NMR, SIMS analysis. Concanamycin B has strong antifungal activity against some phytopathogenic fungi but not antivacterial activity and preventive value were 50% and 100% at 125ppm and 250ppm in pot assay.

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Development of HEA for Terrestrial Digital TV (지상파 DTV 용 HPA 개발)

  • 송명선;이재욱;김혁제;강상기;최재익
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1999.06b
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    • pp.9-13
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    • 1999
  • 이 논문은 디지털 TV 송신기의 구성 시스템 중 하나인 HPA 서브시스템(이하 HPA 시스템이라고 함)을 구현하는 구현 기술에 대하여 기술한다. HPA 시스템은 레벨 제어부, HPA 모듈, 고출력 결합기, 여파기, HPA 감시, 경보 및 제어 시스템으로 구성되어 있다. 이를 구현하기 위해서 전력레벨을 설계하고, 각 레벨에 맞는 4Wpeak, 30Wpeak, 125Wpeak 단위 증폭기를 설계, 제작 시험하였으며, 이들 단위 증폭기를 전력 분배기/결합기를 이용하여 결합하여 600Wpeak급 HPA 모듈을 제작하였다. 자체 제작한 HPA 모듈과 상용 부품을 이용하여 HPA 서브시스템을 구성하였으며, 현장시험을 통하여 그 성능을 입증하였다. 개발한 HPA 시스템은 동작주파수 470MHz-510MHz, 최대출력 1.6kWpeak, 이득 60dB 이상, 채널내 이득 평탄도 0.6dB 이하, 입력 반사손실 -l8dB이하이며, IMD는 3dB back-off시 -35dB이하이다

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Synthesis and Radical Polymerization of p-(2,2,3,3,-Tetracyanocyclopropyl)phenyl Acrylate and Methacrylate

  • Lee, Ju-Yeon;Kim, Kyoung-Ah;Mun, Gil-Soo
    • Bulletin of the Korean Chemical Society
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    • v.14 no.2
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    • pp.283-287
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    • 1993
  • p-(2,2,3,3-Tetracyanocyclopropyl)phenyl acrylate (3a) and p-(2,2,3,3-tetracyanocyclopropyl)phenyl methacrylate (3b) were prepared by the reactions of bromomalononitrile with p-acryloyloxybenzylidenemalononitrile (2a) or p-methacryloyloxy-benzylidenemalononitrile (2b), respectively. Compounds 3a and 3b were polymerized with free radical initiators to obtain the polymers with multicyano functionalities in the cyclopropane ring. The resulting polymer 4a was soluble in acetone but the polymer 4b was not soluble in common solvents. The inherent viscosities of polymers 4a were in the range of 0.10-0.15 dL/g in acetone and those of 4b were in the range of 0.20-0.30 dL/g in 98% sulfuric acid. Solution-cast films were cloudy and brittle, showing $T_g$ values in the range of 106-125$^{\circ}$C.

Significance of the R16 Korea Contest as Culture Contents ('R16 코리아' 대회의 문화콘텐츠적 가치)

  • Kim, Gigook;Lee, Woojae
    • Cross-Cultural Studies
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    • v.39
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    • pp.97-125
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    • 2015
  • Significance of the R16 Korea Contest as Culture Contents. Known for relentless practice and intense moves, widespread presence on the Internet, strong ethnic elements highlighting Korean physical attributes and collective culture, b-boying occupies a special place in Korea today. News of four consecutive wins in major b-boy contests around the world have changed the common public conception that b-boys are simply a group of problem boys and students in hip-hop clothes intent on showing off their dance moves. B-boying is no longer perceived as a dance that is performed in the shadowy underground but as a dynamic and beautiful art form of physical expression that is part of today's popular culture. This paper examines the significance of R-16 Korea as culture contents and its main event, the World B-boy Masters Championship. It introduces how the contest has developed since 2007 to reach popular influence and gain international recognition. The paper also compares R-16 Korea to the world's four major b-boy contests, Battle Of The Year, UK B-boy Championship, Free Style Session, and Red Bull BC One to see if any distinctions could be found among them and to evaluate the significance of R-16 Korea as cultural content in its rise to one of the world's top 5 major b-boy contests. Finally, this study makes suggestions for b-boying to become more established as part of Korea's culture contents.

The Waveform and Spectrum analysis of Tursiops truncatus (Bottlenose Dolphin) Sonar Signals on the Show at the Aquarium (쇼 학습시 병코돌고래 명음의 주파수 스펙트럼 분석)

  • 윤분도;신형일;이장욱;황두진;박태건
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.36 no.2
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    • pp.117-125
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    • 2000
  • The waveform and spectrum analysis of Tursiops truncatus(bottlenose dolphin) sonar signals were carried out on the basis of data collected during the dolphin show at the aquarium of Cheju Pacificland from October 1998 to February 1999. When greeting to audience, the pulse width, peak frequency and spectrum level from the five dolphins'sonar signals were 3.0ms, 4.54kHz and 125.6dB, respectively. At the time of warm-up just before the show, their figures were 5.0㎳, 5.24kHz and 127.0dB, respectively. During the performance of dolphins, with singing, peak frequency ranged 3.28∼5.78kHz and spectrum level ranged 137.0∼142.0dB. With playing ring, pulse width, peak frequency and spectrum level were 7.0㎳, 2.54kHz and 135.9dB, and when playing the ball, the values were 9.0㎳, 2.78kHz and 135.2dB, respectively. The values determined from the five dolphins during jump-up out of water were : pulse width 2.0㎳, peak frequency 4.50kHz and spectrum level 126.8dB. When they responded to trainer's instructions, the values were 2.25㎳, 248kHz and 148.7dB, respectively, and greeting to audience, the peak frequency and spectrum level were 5.84kHz and 122.5dB. During swimming under water, peak frequency and spectrum level were determined to be 10.10kHz and 126.8dB. It was found that there exited close consistencies in pulse width, frequency distribution and spectrum level between whistle sounds and dolphin's sonar signals. Accordingly, the dolphins can be easily trained by using whistle sound based on the results obtained from the waveform and spectrum of the dolphin's sonar signals.

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