• 제목/요약/키워드: ND5

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땅강아지에 의한 인삼의 피해 (Ginseng Damage by the African Mole Cricket, Gryllotalpa africana Palisot de Beauvois)

  • 김기황
    • 한국응용곤충학회지
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    • 제31권4호
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    • pp.379-385
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    • 1992
  • 땅강아지에 의한 인삼의 피해가 1984~1991년에 야외 및 실내에서 조사되었다. 인삼의 땅강아지 피해는 주로 2년근(2년생) 포장에서 5~6월(춘기)에 발생하였고 성주의 야외 밀도가 높은 9~10월(추기)에는 피해가 거의 인식되지 않았다. 실내 및 강실에서, 2년근의 추기 피해는 뚜렷이 감소하였는데 인삼의 직경과는 무관하였으며, 3년근은 전혀 식해되지 않았다. 토양경도는 땅강아지 성충에 의한 인삼의 피해에 영향을 미치는 것으로 보였다.

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인기아와 비인기아에 대한 아동의 인식 발달 (Development of Children's Perceptions of Popular and Unpopular Peers)

  • 강인설;정계숙
    • 아동학회지
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    • 제30권5호
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    • pp.209-224
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    • 2009
  • This study examined the development of children's perceptions of popular and unpopular peers. Subjects were 784 children in kindergarten, $2^{nd}$, $4^{th}$, and $6^{th}$ grades. Research findings were that : (1)socio-metric popularity and perceived popularity correlated positively with athletic ability, academic ability, and prosocial behavior. Whereas two subtypes of aggression(physical aggression and relational aggression) correlated negatively with sociometric popularity, perceived popularity correlated positively with relational aggression in 6th grade. (2)Social behaviors consistently emerged across developmental periods as predictors of popularity. (3)Academic ability was an important characteristic of popular children. (4)Teachers' praise and punishment affected popularity in kindergarten and $2^{nd}$grade children, but peer effect was more important for $4^{th}$ and $6^{th}$graders.

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ADSL 모뎀용 CMOS 시그마-델타 DAC 칩 개발 (Development of CMOS Sigma-Delta DAC Chip for Using ADSL Modem)

  • 방준호;김선홍
    • 전기학회논문지P
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    • 제52권4호
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    • pp.148-153
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    • 2003
  • In this paper, the low voltage 3V Sigma-Delta Digital Analog Converter(DAC) is designed for using in the transmitter of ADSL analog front-end. We have developed the CMOS DAC according to ANSI T1.413-2(DMT) standard specifications of the chip. The designed 4th-order DAC is composed of three block which are 1-bit DAC, 1st-order Switched-Capacitor filter and analog active 2nd-order Resistor-Capacitor(RC) filter. The HSPICE simulation of the designed DAC showing 65db SNR, is connected with 1.1MHz continuous lowpass filter. And also, we have performed the circuits verification and layout verification(ERC, DRC, LVS) followed by fabrication using TSMC 2-poly 5-metal p-substrate CMOS $0.35{\mu}m$ processing parameter. Finally, the chip testing has been performed and presented in the results.

동적거동 관점에서의 돌풍에 대한 고속전철 운행속도 영향 연구 (Analysis of Dynamic Behavior of the High Speed Train by External Force due to the Gust)

  • 박찬경;김영국;최강윤
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집B
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    • pp.495-500
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    • 2001
  • The dynamic behavior of high speed train is very important because it should be safe and is satisfied with the ride comfort of passengers. The railway is composed of many suspension components-1st springs, 1st dampers, 2nd springs, 2nd dampers etc- that have an influence on the dynamic characteristics of high speed train. Also, the wheel/rail shapes, the track condition and geometry and many environmental factors-rain, snow, wind etc-are affected the dynamic behavior of high speed train. This paper is reviewed the effect of wind(gust) on the dynamic behavior of high speed train. Vampire program is used for this simulation. The result of simulation shows that high speed train should not be operated when the gust speed is beyond 34.5m/sec.

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커플시스템의 파라메트릭 모델링 (Parametric Modelling of Coupled System)

  • 윤문철;김종도;김병탁
    • 한국기계가공학회지
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    • 제5권3호
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    • pp.43-50
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    • 2006
  • In this successive study, the analytical realization of coupled system was introduced using the times series identification and spectrum analysis, which was compared with conventional FFT spectrum. Also, the numerical responses of second order system, which is coupled, were solved using the numerical calculation of Runge-Kutta Gill method. After numerical analysis, the displacement, velocity and acceleration were acquired. Among them, the response of displacement was used for the analysis of time series spectrum. Among several time series, the ARMAX algorithm was proved to be appropriate for the spectrum analysis of the coupled system. Using the separated response of 1st and 2nd mode, the mode was calculated separately. And the responses of mixed modes were also analyzed for calculation of the mixed modes in the coupled system.

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호산춘양조에 관한 문헌적 고찰 (A Bibliographical Study on the Manufacturing Procedure of Hosanchun)

  • 남궁석;이성우;배상면
    • 동아시아식생활학회지
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    • 제2권1호
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    • pp.133-138
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    • 1992
  • The research on the manufacturing procedure of Hosanchun jun in the classical literature(17 kinds) showed that the most usually brewed rice wine in it is the 3rd step rice wine, which is brewed by adding rice wine base to it at the intervals used quantity are as follows. Nonglutinous rice(88.2%), flour(82.3%), and nu-ruk(100%) are used in the 1st step of brewing, and nonglutinous rice(82.3%), glutinous rice(17.6%), flour(23.5%), and nu-ruk(11.3%) are used in the 2nd sep, and glutinous rice, flour, and 3rd step of brewing. The grains are used in the form of -paste(88.2%) in the 1st, and in the form of paste(64.7%) and steamed water-soaked rice(sul-bab)(29.4%) in the second step, and sul-bab(64.7%) in the 3rd step of brewing. Nu-ruk is used in small quantity in the 3rd step but it is used I somewhat larger quantity in the 2nd step of brewing.

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원고리형 레이저광에 의한 근사 무회절 광의 발진 (Generation of non-diffraction beam with annular laser output beam)

  • 김현태;박대윤;김기식
    • 한국광학회지
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    • 제12권6호
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    • pp.496-502
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    • 2001
  • Scraper 출력경을 이용하는 불안전 공진기형 Nd:YAG 레이저 발진기에서 고리 두께 0.145mm인 원고리형 레이저광을 얻었으며, 초점거리에 위치한 베셀렌즈를 통과시켜 근사 무회절 광을 얻었다. 초점거리 1 m의 렌즈를 이용하여 얻은 근사 무회절 광에 대해서 렌즈로부터 거리 z의 변화에 따른 출력세기를 측정하여 이론과 비교 ·분석하였다. 또한 초점거리 5m의 렌즈를 이용한 경우, 거리 33m의 지점에서도 근사 무회절광이 지속됨을 확인하였다

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사중경로 Ti:sapphire 레이저 증폭기의 증폭 특성과 자발방출에 의한 증폭 (Characteristics of four-pass Ti:sapphire laser amplifier and amplified spontaneous emission)

  • 김규옥
    • 한국광학회지
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    • 제11권5호
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    • pp.365-370
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    • 2000
  • 편광특성을 이용하여 일직선 위에서 네 번 통과하는 Ti:sapphire 레이저 증폭기를 구성하였다. 증폭기를 펌핑하는 Q-스위칭된 Nd:YAG 레이저의 제2차 고조파 에너지가 188mJ일 때 450mW의 연속 발진 Ti:sapphire 레이저가 34mJ의 에너지, 25ns의 반치폭을 갖는 펄스로 증폭되었다. 한편 Ti:sapphire 결정의 방향을 조절하는 간단한 방법으로 자발방출에 의한 증폭을 최소화할 수 있었다.

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구조적, 기증적 측면에서 본 아동기의 사회적지지 -Social Convoy Model을 토대로- (Convoys of Social Support in Childhood and Early Sdolescence: Structure and Function)

  • 장영서
    • 대한가정학회지
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    • 제36권3호
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    • pp.191-206
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    • 1998
  • The purpose of this study was to explore social support in childhood and early adolescence. The research was based on the social convoy model(Kahn and Antonucci, 1980). The data were collected from questionnaires completed by 656 elementary school children(2nd and 5th grade) and the middle school children(2nd grade) in rural and urban area. The statistical methods adopted for data analyses were frequencies, mean, standard deviation, T-test, One-way ANOVA, Scheffe-test, Two-way ANOVA, and correlation coefficient. Children received more support from parents and friends in convoy function of social support. Convoy size of social support increased with age. Rural children had larger convoy size in the inner circle, and smaller convoy size in the middle circle than urban children did.

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위상잡음 특성을 개선한 주파수 변환 모듈의 설계 및 제작 (Design and Implement of the Frequency-Shifting Module for the Improvement of Phase Noise Performance)

  • 변종대;하태웅;김진수;박준석;임재봉
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제53권5호
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    • pp.273-278
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    • 2004
  • This paper analyzed the phase noise characteristics of frequency-shifting module by figuring out the relationship between the phase noise components of 1st and 2nd local oscillator composing the frequency-shifting module and those of RF output signals shifted in frequency. Also, frequency-shifting module with the improvement of the phase noise performance was designed and implemented by means that the phase noise components of 1st local oscillator were cancelled in the output signal. Output signal has been affected by only phase noise of 2nd local oscillator, which had excellent phase noise performance than that of the 1st local oscillator.