• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.286-291
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• 2003

Asymmetric multiple quantum well ridge waveguide laser diodes (AMQW RWG LDs) with a wide and flat gain spectrum were designed and fabricated. The operating parameters and gain spectra were measured and analyzed for uncoated and anti-reflection (AR) coated LDs. For AR coated 500 mm-long RWG LOs, the extremely flat gain spectrum over a spectral range of 90 nm was obtained at the current 75 ㎃.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.232-238
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• 2020

The objective of the present study was to investigate fish farm and growth performances of Chinese muddy loach (Misgurnus mizolepis) under indoor and outdoor aquaculture conditions for the domestic loach aquaculture industry. The investigation was conducted from August 2017 to October 2019 at one indoor farm (D-site) and two outdoor farms (P1-site and P2-site). Results showed that WG (weight gain), DWG (daily weight gain), and SWG (specific weight gain) based on growth measurements were 175.27±36.2%, 7.98±3.3%, and 0.94±0.2% at D-site, 320±34%, 4.07±0.6%, and 0.55±0.1% at P1-site, and 295.9±53%, 4.15±0.5%, and 0.62±0.1% at P2-site, respectively. WG was higher in outdoor farms (P1-site and P2-site), while DWG and SWG were higher in the indoor farm (D-site). Such differences of the present study might be due to differences in growth, water quality, plant and sale frequency depending on aquaculture types. In particular, outdoor farms takes more than a year to have sales whereas indoor farms can have sales three times in a year.

• Proceedings of the IEEK Conference
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• 2006.06a
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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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• v.16 no.1
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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.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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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.

• The Journal of Korean Medicine
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• v.39 no.4
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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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• v.21 no.2
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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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• v.14 no.9
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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.

• Korean Journal of Optics and Photonics
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• v.6 no.4
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• pp.302-309
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• 1995

We desinged a lattice-matched InGaAs/lnGaAsP quantum well laser that lases at $1.55{\mu}m$ at room temperature, and calculated the gain spectrum as a function of injected carrier density and temperature. For the calculation of band structures and momentum matrix elements, we used a transfer JIlatrix method based on a block-diagonalized 8x8 second-order Ii$.$ P Hamiltonian. This lattice-matched quantum well lases in transverse electric mode. As the temperature increases, the lasing wavelength gets longer, the transparency carrier density increases, and the differential gain is reduced. The temperature dependence of the gain spectrum comes from the temperature dependence of the band structure and that of the Fermi function, and the latter contributes dominantly.nantly.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.621-627
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• 2011

In this paper, we analysed performance for on-wafer GaN HEMT using load-pull in X-band, and studied optimum impedance point based on analysis result. We suggested method of optimum performance device by analysis of optimum impedance for solid state device on-wafer condition before packaging. The measured device is gate length 0.25um, and gate width is 400um, 800um. device 400um is performed $P_{sat}$=33.16dBm, PAE=67.36%, Gain=15.16dBm, and device 800um is performed $P_{sat}$=35.91dBm, PAE=69.23%, Gain=14.87dBm.