• Asian-Australasian Journal of Animal Sciences
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• v.31 no.11
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• pp.1773-1780
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• 2018

Objective: This study was to evaluate effects of mixed plant oils (identified as mixed oil 1 [MO1] and mixed oil 2 [MO2]) on performance, serum composition, viscera percentages, meat quality, and fatty acid deposition of broilers. Methods: A total of 126 one-day-old Arbor Acres male broiler chicks (weighing $44.91{\pm}0.92g$) were randomly allocated to 1 of 3 treatments with 7 replicate pens per treatment (6 broilers per pen). Dietary treatments included a corn-soybean basal diet supplemented with 3% soybean oil (CTR), basal diet with 3% MO1 (a mixture of 15% corn oil, 10% coconut oil, 15% linseed oil, 20% palm oil, 15% peanut oil and 25% soybean oil; MO1), or basal diet with 3% MO2 (a combination of 50% MO1 and 50% extruded corn; MO2). The trial consisted of phase 1 (d 1 to 21) and phase 2 (d 22 to 42). Results: Compared to CTR, broilers fed MO (MO1 or MO2) had greater (p<0.05) average daily gain in phase 1, 2, and overall (d 1 to 42), redness in thigh muscle, concentrations of serum glucose, serum albumin, saturated fatty acids (SFA) and n-6/n-3 polyunsaturated fatty acids (PUFA) ratio in breast muscle, while these broilers also showed lower ($p{\leq}0.05$) drip loss and concentrations of C18:3n-3 and PUFA/SFA ratio in breast muscle. Broilers fed MO2 had higher (p<0.05) liver percentage, while broilers fed MO1 had lower ($p{\leq}0.05$) feed conversion ratio in phase 1 and increased (p<0.05) contents of C18:2n-6, C20:5n-3, C22:6n-3, and n-3 PUFA in breast muscle compared to CTR. Conclusion: Mixed plant oils had positive effects on performance, serum parameters, meat quality, liver percentage and fatty acid deposition in broilers, which indicates they can be used as better dietary energy feedstocks than soybean oil alone.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.938-945
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• 2010

This study was conducted to investigate the dietary effects of germinated and fermented (with Monascus pupureus) soybean screenings (GFS) on growth performance and meat quality in broiler chicken. A total of 750 1-day-old Ross ${\times}$ Ross male broiler chicks were randomly allocated into five groups (five replications with 30 birds each) and fed experimental diets for 5 wks as follows: Group 1, negative-control (antibiotics-free diet); Group 2, positive-control (negative-control with 10 ppm of Avilamycin); Group 3, negative-control with 0.3% GFS; Group 4, negative-control with 0.5% GFS; Group 5, negative-control with 1% GFS. The final body weight of each group fed a diet containing 1% GFS was significantly higher than that of the negative-control group. The feed conversion ratios of all groups fed diets containing GFS and the positivecontrol group were significantly improved compared to the negative-control group during the whole period (p<0.05). The relative weights of various organs along with the activities of serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) were not influenced by the dietary treatments. The levels of total serum cholesterol in groups fed diets containing 0.5% and 1% GFS were more significantly lowered compared to those of the control groups without GFS (p<0.05). There were no significant differences in the cecal microflora profiles among the groups. Further, the dietary treatments did not influence the physico-chemical properties of the edible meat, including the shear force, pH, meat color (CIE $L^*$, $a^*$ and $b^*$), and content of malondialdehyde (MDA). Cooking loss of breast muscle in the groups fed GFS was significantly lowered compared to that of the negative control group (p<0.05). These results indicate that dietary GFS could improve growth performance in broiler chicken and may affect meat quality in some instances.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.375-382
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• 2009

This study examined the influence of forage source (grass hay and rice straw) and shipping time (24, 26, 28 and 30 months) on feed conversion ratio, growth performance and carcass characteristics of Hanwoo steers. Sixty four Hanwoo steers at 6 months age were fed either grass hay (n=32) or rice straw (n=32) for 24, 26, 28 and 30 months of age. Steers fed on mixed grass hay gained significantly higher body weight at 24, 26, 28 and 30 months compared with those fed on rice straw. Feed efficiency was slightly better in steers fed mixed grass hay compared to those fed rice straw. Back fat thickness and marbling score were increased with the age of steers (p<0.05). Carcass quality traits (meat color, fat color, texture and maturity) were not affected by forage source and shipping time. Shear force, cooking loss and water holding capacity of beef were reduced with advancing age of steers (p<0.05). Moisture content was lower and fat content was higher in beef produced from steers fed mixed grass hay than those fed rice straw (p<0.05). Beef juiciness was reduced with the advancing shipping time of steers. In conclusion, it would be beneficial to feed hay compared with rice straw during whole period of Hanwoo steer to produce high quality beef.

• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.139-146
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• 2011

This study was carried out to investigated astaxanthin producing "Xanthophyllomyces dendrohous" on growth performances and meat quality in ducks. A total of 450 ducks (cheribery) were allotted into 3 groups. The three groups were control (commercial feed), treatment 1 (0.1% feed additives), and treatment 2 (0.2% feed additives). Each group had 3 replicates. Viable cell number of "Xanthophyllomyces dendrohous" is $1.0{\times}10^8$ cfu/g. Growth performance carried out during 39 days. Average weight gain was significantly higher (p<0.05) in treatment 2 than that of control. Feed conversion was significantly lower (p<0.05) in treatment 1 and 2 than that of control. The results of nutrients composition analysis of duck meat showed that treatment 1 and 2 had significantly lower (p<0.05) fat and cholesterol levels. Water holding capacity showed significantly higher (p<0.05) value than that of control. Both treatment groups showed lower (p<0.05) value than control in drip loss and shear force. Control showed higher unsaturated fatty acids(palmitic acid, stearic acid) content than treatment 1 and 2. Treatment 1 and 2 showed significantly lower (p<0.05) saturated fatty acids (oleic acid, linoleic acid) levels than control. These results suggested that the supplementation of feed additives containing "Xanthophyllomyces dendrohous" might be used effectively for inproving productivity and meat quality of ducks.

• Journal of Animal Science and Technology
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• v.62 no.1
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• pp.43-51
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• 2020

This experiment was conducted to investigate the effects of exogenous emulsifier supplementation on growth performance, energy digestibility, and meat quality in broilers. A total of 60 Ross 308 broilers were treated for two weeks. The three dietary treatments were: (CON) basal diet; (T1) basal diet + 0.1% exogenous emulsifier, and (T2) basal diet + 0.2% exogenous emulsifier. In Period 1 (0-7 days), broilers in the T2 group showed significantly higher body weight gain (BWG) (p < 0.05) and broilers in the T1 and T2 treatment groups had significantly lower feed conversion ratios (FCR) (p < 0.05). In Period 2 (8-14 days), broilers in the T2 treatment group had significantly higher feed intake (FI) (p < 0.05). Therefore, in this experiment (from days 0 to 19), BWG and FCR were affected (p < 0.05) by the T1 and T2 treatments. Additionally, the T1 and T2 treatments with added exogenous emulsifier in the broiler feed showed significantly higher energy digestibility (p < 0.05) than the CON treatment. Broilers fed the T2 diet had higher water-holding capacity (WHC) (p < 0.05) and cooking loss than the broilers fed the CON and T1 diets. Moreover, the shearing force in the meat was decreased (p < 0.05) in broilers fed the T2 diet. In conclusion, supplementation with exogenous emulsifier to broiler diets improved growth performance, energy digestibility, and meat quality. The optimal amount of exogenous emulsifier supplementation requires further investigation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11A
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• pp.1104-1109
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• 2005

In this paper, a Ka-band harmonic mixer is designed and fabricated on the base of the multiplier theory that there is a bias point to maximize the third harmonic order($3f_{LO}$) with respect to a fundamental LO frequency($f_{LO}$), which can make the high-order mixing element($f_{RF}{\pm}3f_{LO}$) to be greater than other mixing elements, Pumping a RF frequency($f_{RF}$) and LO frequency($f_{LO}$). The harmonic mixer by the proposed design method is fabricated by using a commercial GaAs MESFET device with a plastic package and overcome these disadvantages that a conventional mixer in Ka-band suffer from a high cost, inefficient productivity and circuit complexity. The harmonic mixer have a -10 dB conversion loss at the IF Sequency($3f_{LO}-f_{RF}$=1.0GHz) by selecting a gate bias voltage for the maximum third-order LO harmonic element($3f_{LO}$=34.5 GHz) as pumping LO frequency($f_{LO}$=11.5 GHz) With respect to RF Sequency ($f_{RF}$=33.5GHz)

• Korean Journal of Poultry Science
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• v.47 no.1
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• pp.1-7
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• 2020

The effect of stocking density on the growth and meat quality of native Korean chickens was investigated. A total of 364 one-day-old native Korean chickens were randomly assigned to one of 5 treatments, each of which was replicated 4 times. Five distinct stocking densities-14, 15, 16, 18, and 22 birds/㎡-were compared. The diet was fed ad libitum for 10 weeks. Results indicated that the final body weight, body weight gain, and feed intake were lower (P<0.05) for the 22 birds/㎡ stock density as compared to the other stock densities. There was no significant difference in the feed conversion ratio, proximate analysis (DM, crude protein, crude fat, and crude ash), water-holding capacity, and cooking loss among the different stock densities. These results indicate that increasing the stock density to 22 birds/㎡ elicits some negative effects on the growth performance and meat quality of Korean-native chickens.

• Polymer(Korea)
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• v.30 no.6
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• pp.478-485
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• 2006

Physical properties and flammability of polyhydroxyamides (PHAs) haying poly (ethylene-glycol) methyl ether (MPEG) and/or dimethylphenoxy pendants were studied by using DSC, TGA, FTIR, pyrolysis combustion flow calorimeter (PCFC), and X-ray diffractometer. The degradation temperatures of the polymers were recorded in the ranges of $276{\sim}396^{\circ}C$ in air. PCFC results showed that the heat release (HR) capacity and total heat release (total HR) values of the PHAs were increased with in-creasing molecular weight of MPEG. In case of M-PHA 2 annealed at $290^{\circ}C$, the values of HR capacity were siginificantly decreased from 253 to 42 J/gK, and 60% weight loss temperatures increased from 408 to $856^{\circ}C$ with an annealing temperature. The activation energy for the decomposition reaction of the PHAs showed in the range of $129.3{\sim}235.1kJ/mol$, which increased with increasing conversion. Tensile modulus of PHAs were decreased as increasing chain of MPEG, and showed an increase more than initial modulus after converted to PBOs.

• Journal of the Korean Vacuum Society
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• v.20 no.2
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• pp.77-85
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• 2011

The silicon-germanium (SiGe) alloy, which is compatible with silicon semiconductor technology and has a smaller band gap and a lower thermal conductivity than silicon, has been used to fabricate electronic devices such as transistors, photodetectors, solar cells, and thermoelectric devices. This paper reviews the application of SiGe alloys to electronic devices and related technical issues. Since the SiGe alloy comprises germanium whose band gap is smaller than silicon, its band gap is also smaller than that of silicon irrespective of the ratio of silicon to germanium. This narrow band gap of SiGe enables the base thickness of bipolar transistors to decrease without a loss in current gain so that it is possible to improve the speed of bipolar transistors by adopting the SiGe-base. In addition, the conversion efficiency of solar cells is enhanced by the absorption of long-wavelength light in the SiGe absorption layer. Phonon scattering caused by the irregular distribution of alloying elements induces the lower thermal conductivity of SiGe than those of pure silicon and germanium. Because a thin film layer with a low thermal conductivity suppresses thermal conduction through a thermal sink, the SiGe alloy is considered to be a promising material for silicon-based thermoelectric systems.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.1 s.116
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• pp.37-43
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• 2007

In this.paper, we introduce design and implementation results of the single balanced diode mixer for European point-to-point microwave radio in order to improve flatness performance. When a resonator such as RF filter is integrated with a mixer, impedance characteristic of 50 ohm is maintained only in RF band, not in LO band resulting deterioration of flatness performance because of LO power variation on the diode. In the paper, we suggest a design method of mixer integrated with image rejection filter and LO harmonic filter to have a better performance of flatness using embedding electrical length between filter and mixer's port. Frequency specification of fabricated mixer is $21.2{\sim}22.6\;GHz$ for RF, $19.32{\sim}20.72\;GHz$ for LO and 1.88 GHz+/-50 MHz for IF, respectively. Measured results show conversion loss of 8.5 dB, flatness of 2 dB, input PldB of 8 dBm, IIP3 of 15 dBm under LO power level of 10 dBm. Return losses of RF, LO and IF port are under -12 dB, -10 dB and -5 dB, respectively. Isolations of LO/RF and LO/IF are 20 dB and 50 dB, respectively.