• 한국광학회지
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• 제14권3호
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• pp.286-291
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• 2003

광대역 이득 특성을 얻기 위한 InGaAsP-InP 응력보상 비대칭 다중 양자우물(Asymmetric Multiple Quantum Well, AMQW) 구조를 성장하고, Ridge Waveguide Laser Diodes(RWG-LDs)를 제작하였다. 제작 후 소자의 동작변수와 모드 이득을 측정하였으며, 얻어진 결과를 비교, 분석하였다. 외부 공진기형 구조에서 넓고 평탄한 이득특성을 얻기 위해 한쪽 단면에 Anti-Reflection(AR) 코팅을 수행하여 AR coated AMQW RWG LD의 이득특성을 분석하였다.

• 한국어류학회지
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• 제32권4호
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• pp.232-238
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• 2020

본 연구는 실내외 양식방법에 따른 미꾸라지 양식장 모니터링과 성장특성을 조사하여 국내 미꾸라지 양식산업에 대한 기초자료를 확보하고자 수행하였다. 조사는 2017년 8월부터 2019년 10월까지 실내 양식장 1개소 (D-site), 실외양식장 2개소 (P1-site, P2-site)를 선정하여 수행하였다. 성장도 측정결과를 토대로 WG (weight gain), DWG (daily weight gain), and SWG (specific weight gain) 분석한 결과 D-site에서는 175.27±36.2%, 7.98±3.3%, 0.94±0.2%, P1-site에서 320±34%, 4.07±0.6%, 0.55±0.1%, P2-site에서 295.9±53%, 4.15±0.5%, 0.62±0.1%로 나타났다. WG는 실외노지 양식장(P1-Site과 P2-site)에서 높았지만 DWG와 SWG는 실내양식장(D-site)에서 높게 나타났다. 본 조사 결과의 차이는 실내외 양식방법에 따른 성장도, 수질환경, 출하시기 및 횟수 차이로 인한 것으로 판단된다. 특히 실외 양식은 출하시기까지 1년 이상 소요되었으나 실내 양식은 1년에 3회의 출하가 가능한 것으로 나타났다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.609-610
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• 2006

A 77GHz MMIC transceiver module consisting of a power amplifier, a low noise amplifier, a drive amplifier, a frequency doubler and a down-mixer has been developed for automotive forward-looking radar sensor. The MMIC chip set was fabricated using $0.15{\mu}m$ gate-length InGaAs/InAlAs/GaAs mHEMT process based on 4-inch substrate. The power amplifier demonstrated a measured small signal gain of over 20dB from $76{\sim}77GHz$ with 15.5dBm output power. The chip size is $2mm{\times}2mm$. The low noise amplifier achieved a gain of 20dB in a band between $76{\sim}77\;GHz$ with an output power of 10dBm. The chip size is $2.2mm{\times}2mm$. The driver amplifier exhibited a gain of 23dB over a $76{\sim}77\;GHz$ band with an output power of 13dBm. The chip size is $2.1mm{\times}2mm$. The frequency doubler achieved an output power of -16dBm at 76.5GHz with a conversion gain of -16dB for an input power of 10dBm and a 38.25GHz input frequency. The chip size is $1.2mm{\times}1.2mm$. The down-mixer demonstrated a measured conversion gain of over -9dB. The chip size is $1.3mm{\times}1.9mm$. The transceiver module achieved an output power of 10dBm in a band between $76{\sim}77GHz$ with a receiver P1dB of -28dBm. The module size is $8{\times}9.5{\times}2.4mm^3$. This MMIC transceiver module is suitable for the 77GHz automotive radar systems and related applications in W-band.

• Asian-Australasian Journal of Animal Sciences
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• 제16권1호
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• pp.70-76
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• 2003

Three experiments were conducted to determine the effects of a sorghum-specific enzyme system, derived from an Aspergillus niger and Bacillus subtilis fermentation extract (carbohydrase activity of 1,650 $\alpha$-amylase units and cellulase activity of 30 fibrinolytic units/mL), on growth performance of finishing pigs. In Exp. 1,192 pigs (average initial BW of 46.1 kg) were fed sorghum-based diets without or with 360 mL of enzyme system per ton of sorghum in a 78 d growth assay. For d 0 to 39, gain/feed was improved (p<0.03) with enzyme supplementation, but ADG was not affected (p>0.15). For d 39 to 78 and overall (d 0 to 78), ADG, gain/feed, and digestibilities of DM and N were not affected (p>0.13) by enzyme supplementation. Backfat thickness, fat-free lean index, and scores for stomach keratinization and ulcers also were not affected (p>0.15) by the dietary treatments. In Exp. 2,168 pigs (average initial BW of 58.4 kg) were fed diets without or with 150, 300, or 450 mL/ton of the same enzyme system used in Exp. 1. Adding as much as 450 mL enzyme system / ton of sorghum did not affect (p>0.15) ADG or gain/feed for d 0 to 29 of the growth assay. However, during d 29 to 63, ADG increased by 11% (linear effect, p<0.02) and gain/feed increased by 10% (linear effect, p<0.06) as enzyme concentration was increased from none to 450 mL/ton of sorghum. For the overall period (d 0 to 63), ADG tended to increase (p<0.08) with enzyme supplementation, but gain/feed and digestibilities of DM and N were not affected (p>0.14). Carcass characteristics (dressing percentage, backfat thickness, and fat free lean index) also were not affected (p>0.20) by addition of the enzyme system. In Exp. 3,176 pigs (average initial BW of 46.7 kg) were fed diets without or with 450, 900, or 1,350 mL/ton of the same enzyme system used in Exp. 1 and 2 in a 71 d growth assay. Adding up to 1,350 mL/ton of enzyme had no effects (p>0.15) on ADG, gain/feed, digestibilities of DM and N, and carcass characteristics (dressing percentage, backfat thickness, and fat-free lean index). In conclusion, finishing pigs fed diets with a sorghum-specific enzyme system showed some positive trends for improved growth performance, but those effects were not large and (or) consistent.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.150-153
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• 2000

In this paper, we have designed a 2 stage MMIC power amplifier which has flat gains of in-band and reasonable out-band cutoff characteristics using 0.5$\mu\textrm{m}$ MESFET libra교 of ETRI. For the 1st stave, we obtaind P$_{1dB}$ of 9.2 dBm and gain 10.8 dB using 6 finger D-MESFET and P$_{1dB}$ of 18.4 dBm and gain of 10.8 dB using 14 finger D-MESFET for the 2nd stage, which is power matched using LIBRA's embedded TUNER. Also in-band gain flatness and out-band cutoff characteristics are obtained by attaching LC tank in the output matching circuit. The designed 2 stage MMIC power amplifier has bandwidth of 0.95～2.8 GHz, gain of 20 dB and P$_{1dB}$of 17.2 dBm. Especially gain flatness of $\pm$0.8dB was obtained in 1.8～2.5 GHz frequency ranges. And chip size is 1.4$\times$1.4 mm..4 mm.

• 대한한의학회지
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• 제39권4호
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• pp.16-29
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• 2018

Introduction: We aimed to investigate the predictive factors and optimal age for response to herbal medicine treatment for height gain in children. Methods: This retrospective chart review included 61 children (age range, 5-16 years) treated for height gain between 2011 and 2015. A predictive model was established by multiple linear regression analysis. Dependent variables were defined by the differences in percentile before and after herbal medicine treatment. The optimal cutoff value of patient age was determined by receiver operating curve analysis. Results : The age of initiation of herbal medicine therapy (p = 0.012) and administration of Forsythiae fructus (p = 0.002) were significant variables for treatment response. The adjusted R2 value was 0.231. The mean ages of the responder and non-responder groups were significantly different (p = 0.023). The optimal cutoff value of age for predicting treatment response was 9.75 years. Treatment response was better among children below 9.75 years of age. Conclusions: Patient age and administration of Forsythiae fructus were identified as determinants of response to herbal medicine treatment. Treatment of rhinitis and initiation of height gain treatment at an early age are critical for better response. These findings will provide fundamental data for further research.

• Asian-Australasian Journal of Animal Sciences
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• 제21권2호
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• pp.262-269
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• 2008

The aim of this study was to determine the effects of breeder age and stocking density on performance, carcass characteristics and some stress parameters (H-L ratio, serum glucose, cholesterol and triglyceride levels, tonic immobility test (TI), antibody production, relative asymmetry (RA) and external appearances). This experiment was carried out with 705 one-day old male broiler chicks (Ross 308) obtained from three different ages of broiler breeder (32, 48 and 61 wks). Each age group was randomly divided into two stocking density groups (11.9 and 17.5 broilers per $m^2$) with 5 replications per group. The experimental period was 6 weeks. Broilers from 32 wk-old breeders had lower initial weight (p<0.001), body weight gain of the first 3 week of rearing (p<0.01), the percentage of abdominal fat (p<0.001) and serum cholesterol level (p<0.01); higher percentage of gizzard (p<0.01) and longer TI duration (p<0.001) than those from 48 and 61 wk-old breeders. Broilers reared at 17.5 b/m2 had lower final BW, body weight gain, feed consumption, feather condition and foot health (p<0.001), higher percentage of heart, H-L ratio, serum glucose and cholesterol levels (p<0.001), and longer TI durations (p<0.001). There were no significant interactions in examined parameters except for feed to gain ratio between breeder age and stocking density.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1245-1249
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• 2001

A study was conducted with 14 gayals to study their growth pattern from birth to 24 months of age, and gayal was compared with native calves and crossbred calves of gayals and exotic animals. A significant difference in liveweight gains up to 3 months (p<0.001) or up to 6 months (p<0.05) was found between gayal and native calves, but the difference reduced with increase of age and found non-significant (p>0.05) at 9 months and 12 months. The daily liveweight gain up to 3, 6, 9 or 12 months of age of gayals were 404.60, 306.80, 315.20 and 312.20 g/d, respectively and of native calves were 217.3, 245.3, 262.0 and 269.0 g/d, respectively. Gayal female calves had lower weights at birth (20.2 kg) and weaning (81.8 kg) and daily liveweight gains (298.5 g/d) than males (24.3 kg, 84.0 kg and 317.8 g/d, respectively) but the differences were not significant (p>0.05). Cross breeding gayal cows with Friesian bulls increased daily liveweight gain of the crossbred calves. The rate of increase of daily liveweight gain may further be increased if gayals are crossed with beef type animals, and optimum feeding may also be required which needs further research.

• 한국광학회지
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• 제6권4호
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• pp.302-309
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• 1995

상온에서 $1.55{\mu}m$ 를 발진하는 격자 정합된 InGaAs/InGaAsP 양자우물 레이저를 설계하여 주입 운반자 밀도와 온도의 함수로 이득 곡선을 계산하였다. 밴드 구조와 운동량 행력 요소의 계산에는 블록대각화된 8*8 이차 k.p 해밀토니안에 근거한 변환행렬법을 사용하였다. 이 격자정합된 양자우물은 TE 모우드로 발진하였다. 온도가 증가함에 따라 발진파장이 길어졌고, 투명 운반자 밀도는 증가하였으며 미분이득은 감소하였다. 이득 곡선의 온도의존도는 밴드 구조의 온도의존성과 페르미 함수의 온도의존성에 기인하는데 이중 후자의 효과가 주도적인 것이었다.

• 한국전자통신학회논문지
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• 제6권5호
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• pp.621-627
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• 2011

본 논문에서는 로드-풀을 이용하여 X-band에서 on-Wafer 상태의 GaN HEMT 소자에 대한 성능을 분석하고 분석한 결과를 바탕으로 최적의 임피던스 점을 분석하였다. 패키징 하기 전 on-Wafer 상태에 있는 반도체 소자의 최적의 임피던스 분석을 통해 소자 자체에서 최적의 성능을 내는 방안을 제안하였다. Gate length가 0.25um이고 Gate Width가 각각 400um, 800um인 소자에 대한 최적의 임피던스를 선정하여 성능을 분석한 결과, 400um는 $P_{sat}$=33.16dBm(2.06W), PAE=67.36%, Gain=15.16dBm의 성능을 가지며, 800um는 $P_{sat}$=35.9 dBm(3.9W), PAE=69.23%, Gain=14.87dB의 성능을 보였다.