• Korean Journal of Veterinary Research
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• v.14 no.2
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• pp.233-236
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• 1974

This experiment was carried out for 42 days to investigate the effect of caponizing and diethylstilbestrol (DES) on body weight gain, rate of feed conversion, weight of carcass and percentage of dressing in young chickens. The chickens used were 128 male Hamphorn of 30 days old. In the body weight gain of chickens, control group was higher than the other groups (P<0.01); $T_1$ group was the lowest group. Rate of feed conversion of control group was higher than $T_2$ and $T_3$ groups.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.288-297
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• 2008

Recent research efforts on study of silicon photonics utilizing stimulated Raman scattering have largely overlooked temperature effects. In this paper, we incorporated the temperature dependences into the key parameters governing wave propagation in silicon waveguides with Raman gain and investigated how the temperature affects the solution of the coupled-mode equations. We then carried out, as one particular application example, a numerical analysis of the performance of wavelength converters based on stimulated Raman scattering at temperatures ranging from 298 K to 500 K. The analysis predicted, among other things, that the wavelength conversion efficiency could decrease by as much as 12 dB at 500 K in comparison to that at the room temperature. These results indicate that it is necessary to take a careful account of temperature effects in designing, fabricating, and operating Raman silicon photonic devices.

• Journal of Power Electronics
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• v.14 no.4
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• pp.806-813
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• 2014

Planar electromagnetic interference (EMI) filters are widely used to restrain the conducted EMI of switching power supplies. Such filters are characterized by small size, low parasitic parameters, and better high-frequency performance than the passive discrete EMI filter. However, EMI filter performance cannot be exactly predicted by using existing methods. Therefore, this paper proposes a method to use scattering parameters (S-parameters) for the measurement of EMI filter performance. A planar EMI filter sample is established. From this sample, the relationship between S-parameters and insertion gain (IG) of EMI filter is derived. To determine the IG under different impedances, the EMI filter is theoretically calculated and practically measured. The differential structure of the near-field coupling model is also deduced, and the IG is calculated under standard impedance conditions. The calculated results and actual measurements are compared to verify the feasibility of the theory.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.5
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• pp.319-326
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• 2019

The use of high-voltage gain converters is essential for distributed power generation systems with renewable energy sources, such as fuel and solar cells, due to their low-voltage characteristics. In this study, a novel high-voltage gain non-isolated buck boost converter topology is proposed to cope with the need of a high-voltage conversion ratio without the transformer for the renewable energy sources. Given that the proposed topology utilizes the cascode structure, the voltage gain and the efficiency are higher than those of other conventional non-isolated converters. To demonstrate the feasibility of the proposed topology, the operation principle is presented, and the steady-state characteristics are analyzed in detail. The validity of the proposed converter is verified by experiments with a 400 W prototype converter.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.2
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• pp.147-155
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• 2002

This paper describes RF front-end transceiver chipset for the dual-mode operation of PCS-Korea and IMT-2000. The transceiver chipset has been implemented in a $0.25\mutextrm{m}$ single-poly five-metal CMOS technology. The receiver IC consists of a LNA and a down-mixer, and the transmitter IC integrates an up-mixer. Measurements show that the transceiver chipset covers the wide RF range from 1.8GHz for PCS-Korea to 2.1GHz for IMT-2000. The LNA has 2.8~3.1dB NF, 14~13dB gain and 5~4dBm IIP3. The down mixer has 15.5~16.0dB NF, 15~13dB power conversion gain and 2~0dBm IIP3. The up mixer has 0~2dB power conversion gain and 6~3dBm OIP3. With a single 3.0V power supply, the LNA, down-mixer, and up-mixer consume 6mA, 30mA, and 25mA, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.425-430
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• 2006

Three hundred and sixty sexed 3-day-old broiler chicks were divided randomly into six treatment groups (control, antibiotic and black cumin at four levels) of 60 birds each. Black cumin seeds at 0.5%, 1%, 2% or 3% and avilamycin at 10 mg/kgt were added to the basal diet and their effects determined on feed intake, daily live weight gain, feed conversion ratio and carcass characteristics. There were no significant differences in daily feed intake at 21 and 42 days (p>0.05). Average daily gain was significantly different between the treatments. The birds fed the diet containing 1% black cumin seeds and antibiotic were the highest average daily gain, followed by those the other treatment diets and negative control (p<0.05). From 1 to 42 days of age, feed conversion ratios were improved significantly by supplementation with 1% black cumin seeds and with antibiotic (p<0.05) by approximately 5% compared to the control group. Similarly, the highest cold carcass, thigh, breast, wing, neck and liver weights were observed in the 1% black cumin and antibiotic groups (p<0.05). Accordingly, 1% supplementation of black cumin seeds to diets could be considered as an alternative natural growth promoter for poultry instead of antibiotics.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.3
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• pp.433-437
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• 2015

We have designed and fabricated a low power and high linearity up down convertor for wireless repeaters using $0.35{\mu}m$ SiGe Bipolar CMOS technology. Repeater is composed of a wideband up/down converting mixer, programmable gain amplifiers (PGA), input buffer, LO buffer, filter driver amplifier and integer-N phase locked loop (PLL). As of the measurement results, OIP3 of the down conversion mixer and up conversion mixer are 32 dBm and 17.8 dBm, respectively. The total dynamic gain range is 31 dB with 1 dB gain step resolution. The adjacent channel leakage ratio (ACLR) is 59.9 dBc. The total power consumption is 240 mA at 3.3 V.

• Journal of IKEEE
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• v.24 no.4
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• pp.942-949
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• 2020

In this paper, we propose an improved algorithmic ADC for CMOS Image Sensor that is suitable for a column-parallel readout circuit. The algorithm of the conventional algorithmic ADC is modified so that it can operate as a single amplifier while being independent of the capacitor ratio and insensitive to the gain of the op-amp, and it has a high conversion efficiency by using an adaptive biasing amplifier. The proposed ADC is designed with 0.18-um Magnachip CMOS process, Spectre simulation shows that the power consumption per conversion speed is reduced by 37% compared with the conventional algorithmic ADC.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.377-381
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• 2002

The growth rate, feed conversion efficiency and carcass characteristics of nine native Malpura (M) and eight Awassi ${\times}$ Malpura half bred (AM) male lambs were compared under intensive feeding on 60:40 concentrate and roughage based composite feed. Weaning body weight was similar in the two genetic groups while finishing body weight, total body weight gain and average daily gain during the experiment were higher (p<0.01) in AM than M lambs. The feed conversion efficiency was lower in M than AM lambs with 15.7 and 19.8 per cent feed conversion efficiency, respectively, in the two genetic groups. The dressing yield in terms of preslaughter weight or empty live weight was however similar in the two genetic groups. The loin eye area was also greater (p<0.01) in AM than M lambs. The cutability was similar for the two groups amounting to 33.2, 13.3, 13.2, 23.3 and 16.6% of half carcass, respectively, for leg, loin, rack, neck and shoulder and breast and foreshank. On an average the separable lean, fat and KOH bone content of the half carcass were 48.3, 16.8 and 23.3% for native M and 54.1, 15.0 and 19.0% for AM lambs, respectively. It is concluded that growth rate and feed conversion efficiency were better in Awassi ${\times}$ Malpura half bred than native Malpura lambs while dressing yield and cutability of standard cuts were similar in the two genetic groups.

• Korean Journal of Poultry Science
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• v.28 no.1
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• pp.61-67
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• 2001

Two experiments were conducted to evaluate the dietary supplemental fruit extract(Bio-plus) on performance and intestinal microflora of broiler chicks. Seven treatments were allocated into control, 0.05, 0.10, 0.20, 0.10, 0.20, 0.40, 0.80, 1.60% with four replications for five weeks, in both experiments. Diets contained 21.5% CP, 3, 100 kcal/kg ME for the rest two weeks. Weight gain, feed intake, feed conversion ratio(FCR) were weekly measured. Birds were sacrificed to examine the E. coli and Salmonella from cecum and ileum at the end of experiment. In experiment 1, Weight gain of Bio plus treatments tended to increase compared to that of control, but was not consistency between them. Chicks fed Bio-plus showed significantly lower feed conversion ratio(FCR) than control(P〈0.05). In experiment 2, Weight gain of Bio plus treatments was significantly different from control(P〈0.05) for starting period and linearly increased upto 0.80% for the rest of two weeks, but was not significantly different. Feed intake of chicks fed Bio-plus tended to be higher than control. Bio-plus treatments was not statistically different FCR from control. ND titer showed no significance, but tended to be higher in Bio-plus treatments than control. The number of ileum salmonella was significantly decreased in Bio-plus treatments compared to that of control in expt 2 (P〈0.05). Total yeast and Lactobacillus spp. of illeum tended to increase in expt 1 and were significantly higher in expt 2 than control(P〈0.05). The results of these experiment indicated that dietary Bio-plus supplements increased weight gain, the number of ileum yeast and Lactobacillus spp. of broiler chicks.