• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.527-532
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• 2015

This study was performed to investigate the phyico-chemical characteristics of breast meat from spent hens (SP) in comparison with the same part from the broilers (BR). The moisture and crude protein contents for SP were 72.56% and 24.26%, which were lower than 75.87% and 24.64% for BR. Crude fat and crude ash contents in SP were 0.45% and 1.00%, which were higher than the BR contents of 0.41% and 0.51%. The respective L, a and b value for SP were 48.61, 2.40 and 2.42, which were lower than the BR values of 49.41, 1.45 and 3.06 respectively. The pH for SP was 5.89, which was higher than pH 5.79 for BR. The WHC for SP was 50.29%, which was lower than that of BR at 62.31%. SP scored 28.04% in the heating loss test, which was significantly higher than 19.09% for BR. The shear forces for SP and BR were 4.86 kg and 1.36 kg respectively, which meant that the texture of SP was much tougher than that of BR. Hardness for SP was 8.89 kg while that of BR was 3.92 kg indicating that the SP texture is firmer than that of BR. Oleic acid was most abundant fatty acid in both samples and was at 44.15% in SP and 27.68% in BR.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.1
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• pp.113-117
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• 1994

The effect if heat treatment (autoclave) in amino acid digestibility of winged bean determined using intact cockerels had been investigated. The winged beans were autoclaved at $120^{\circ}C$ for 45 or 90 min, respectively, and the soybean were autoclaved for 45 min. The treated winged bean and soybean were fed to 3 intact cockerels, which had been previously starved for 24 h. Excreta were collected individually for 49 h. The amino acids contained in the diets and excreta were determined to measure the digestibility values. Apparent and true digestibilities of all amino acids except histidine of unheated winged bean were significantly (P < 0.05) lower than those of heated winged bean and soybean. Heat treatment significantly (p < 0.05) improved amino acid digestibility of winged bean, However, over heating (90 min if autoclaving) destroyed lysine, cystine and arginine of winged bean. The true digestibility values of all amino acids of winged bean heated for 90min were the same as those values of treated soybean. However, true digestibilities of glycine, alannine, phenylalanine and lysine of treated soybean were significantly (p < 0.05) higher than those of winged bean heated for 45 min.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.104.1-104.1
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• 2010

We investigated combustion characteristics of wood pellets in a combustion equipment with adjusting amount of flue gas. Maximum temperature in a combustion chamber was $850^{\circ}C$. Higher heating Value of a domestic wood pellet tested is 19.1 MJ/kg and water content was 8.3%. Amount of flue gas causes big effect on burning characteristics in $450{\sim}600^{\circ}C$. Wood pellet does not burn in low temperature atmosphere less than $450^{\circ}C$ and low flue gas flow rate. We made burning the pellet that is made in Korea, USA, Chile and Canada. Color of foreign pellets are bright brown and they made by mainly sawdust. Korean pellet is a dark brown color because it contains bark. There are some differences in the result of elementary analysis and technical analysis. According to the result of burning experiment, burning times of each countries's pellet are similar.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.4
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• pp.593-600
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• 1992

Animal welfare is often neglected by livestock productionists when considering the utilization of animal wastes for livestock feeds. The present review has been carried out to examine the nutritive value of poultry wastes for ruminants, the health risks involved with feeding it, the treatment and feeding methods and the production responses of animals fed on it. It was found that mineral, crude protein, crude fibre and metabolisable energy concentrations are influenced by the system of poultry production, the storage of the waste and the treatment method. Heating at $60^{\circ}C$ kills all pathogens apart from Clostidium botulinum whereas proper ensiling kills all. Apart from the kidney fat and the liver, animal tissues have not shown residues of drugs or heavy metals from poultry wastes. Palatability is affected when the moisture is more than 200 g/kg. Production responses are satisfactory when poultry wastes replace portions of concentrates. It was concluded that poultry litter generally has higher metabolisable energy contents than poultry manure, but research is needed to classify poultry litters on their energy values. The adverse effects of toxic minerals and drug residues are negligible in balanced poultry waste feeding systems.

• Journal of IKEEE
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• v.22 no.1
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• pp.213-215
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• 2018

In this study, we fabricate amorphous carbon thin films on silicon substrates by DC sputtering method and investigate the optical property and photothermal characteristics. A representative amorphous carbon thin film has a absorption value of 97% at a wavelength of 1000 nm and shows a temperature increase of $3^{\circ}C$ from $21.1^{\circ}C$ to $24.1^{\circ}C$ during white light irradiation. In addition, the amorphous carbon film has a heating rate four times higher than that of the substrate during light irradiation for 50 sec.

• Architectural research
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• v.18 no.4
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• pp.151-155
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• 2016

It is necessary to improve the performance of buildings with respect to the energy efficiency while improving the quality of occupants' lives through a sustainable built environment. During the design and development process, building projects must have a comprehensive, integrated perspective that seeks to reduce heating, cooling and lighting loads through climate-responsive designs. The aim of this study is to find an optimal thermal transmittance (U-values) for building envelope elements for low energy multi-rise residential buildings in the early design phase in Korea. The study found that using small U-values of $0.15w/m^2K$ for exterior walls, ceilings and floors and $1.0w/m^2K$ for south and north facing windows has resulted in energy reduction of 22.1%-59.4% in the south facing rooms and 43%-77.6% of the north facing rooms. It has also found the energy load reduction potential of using small U-values are higher on the north facing rooms. The findings of this study can be suggested to be used as a baseline case for low energy consumption studies. It can also be used to determine appropriate envelope materials and insulation values.

• Journal of the Korean housing association
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• v.21 no.6
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• pp.81-90
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• 2010

The existing most studies on the apartment sales prices have been limited to relatively small size apartment complexes and have not categorized the apartment complexes based on the number of households. Some of them uses the apartment-related indices such as regional value estimates, sales unit price, and view right values. In the case of Seoul Metropolitan Area, the size of apartment complex has been growing to the level of large complex over more than 1,000 households through new town development, redevelopment and reconstruction. People prefers to choose a large scale complex instead of small complex based on their perception that a large scale apartment complex provides more conveniences in living. The result of this analysis revealed that the variables chosen as important determinants of the hedonic price model for large scale apartment complexes were square meters of apartment unit, rent/price ratio, number of bays, distance to the nearest subway station, and heating system method. This means that the sales price of apartment unit will be higher as the square meters of apartment unit increase, as the rent/price ratio decreases, as the distance to the nearest subway station increases, and as the number of bays increase.

• Journal of Microbiology
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• v.33 no.2
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• pp.115-119
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• 1995

The alkaline protease of Xanthomonas sp. YL-37 has been purified, and the properties of the enzyme investigated. The alkaline protease of Xanthomonas sp. YL-37 was purified form crude enzyme by ammonium sulfate fractionation, CM-cellulose ion exchange chromatography, and Sephadex G-100 gel filtration. Through the series of chromatographies, the enzyme was purified to homogenecity with specific activity of 4.23 fold higher than that of the crude broth. The molecular weight of the purified protease has been estimated to be 62 KDa on SDS-polyacrylamide gel electrophoresis. The optimal pH and temperature for alkaline protease activity were 11.0 and 50.deg.C, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to 50.deg.C. Enzyme activity was lost up to 50% on heating at 70.deg.C for 30 minutes. The activity of alkaline protease was inhibited by Cu$\^$2+/, Zn$\^$2+/, Hg$\^$2+/, PMSF, and activated by Mn$\^$2+/ and Ca$\^$2+/. The $K_{m}$ value for casein as a substrate was 4.0 mg/ml.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.1
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• pp.54-61
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• 2008

Integrated Gasification Combined Cycle (IGCC) power plant converts coal to syngas, which is mainly composed of hydrogen and carbon monoxide, by the gasification process and produces electric power by the gas and steam turbine combined cycle power plant. The purpose of this study is to investigate the influence of using syngas in a gas turbine, originally designed for natural gas fuel, on its performance. A commercial gas turbine is selected and variations of its performance characteristics due to adopting syngas is analyzed by simulating off-design gas turbine operation. Since the heating value of the syngas is lower, compared to natural gas, IGCC plants require much larger fuel flow rate. This increases the gas flow rate to the turbine and the pressure ratio, leading to far larger power output and higher thermal efficiency. Examination of using two different syngases reveals that the gas turbine performance varies much with the fuel composition.

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.14-20
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• 2018

Purpose: The purpose of this study was to investigate the performance of a vacuum pyrolysis system, to analyze bio-oil characteristics, and to examine the applicability for farm-scale capacity. Methods: The biomass was pyrolyzed at 450, 480, and $490^{\circ}C$ on an electric heat plate in a vacuum reactor. The waste heat from the heat exchanger of the reactor was recycled to evaporate water from the bio-oil. The chemical composition of the bio-oil was analyzed by gas chromatography-mass spectrometry (GC-MS). Results: According to the analysis, the moisture content (MC) in the bio-oil was approximately 9%, the high heating value (HHV) was approximately 26 MJ/kg, and 29 compounds were identified. These 29 compounds consisted of six series of carbohydrates, 17 series of lignins, and six series of resins. Conclusions: Owing to low water content and the oxygen content, the HHV of the bio-oil produced from the vacuum reactor was higher by about 6 MJ/kg than that of the bio-oil produced from a fluidized bed reactor.