• Food Science of Animal Resources
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• v.24 no.3
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• pp.209-215
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• 2004

In a trial involving 120 pigs, the growth performance of finishing pigs and proximate composition, physicochemical properites and fatty acid composition of loin muscle were investigated by feeding the high-energy density diet and low-energy density diet. The treatments included feeding 1) the low-energy density diet (3,290 cal/kg DE, 14.50% CP, 0.70% lysine and 0.78% Ca) for 38 days and 2) the hight-energy density diet (3,350 cal/kg ME, 15.0% CP, 0.70% lysine and 0.78% Ca) for 27 days. The average daily gains were significantly higher for pigs fed the high-energy density diet than those fed the low-energy density diet, but average daily feed intake and feed conversion rate were significantly lower than those fed the low-energy density diet (p<0.05). The cooking loss and yellowness of pork were significantly (p<0.05) lower for pigs fed the low-energy density diet than those fed the high-energy density diet. There were no significant differences in carcass characteristics, proximate composition and fatty acid composition of pork. In conclusion, the results of the experiment suggested that the high-energy density diet for pigs tended to improve the growth performance, but the cooking loss and yellowness of pork were higher for pigs fed the high-energy density diet than those fed the low-energy density diet.

• Journal of the Semiconductor & Display Technology
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• v.13 no.3
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• pp.39-43
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• 2014

The effect of electrode charging on the ion energy distribution (IED) was investigated in the dual-frequency capacitively coupled plasma source which was powered of 100 MHz RF at the top electrode and 400 kHz bias on the bottom electrode. The charging property was analyzed with the distortion of the measured current and voltage waveforms. The capacitance and the resistance of electrode sheath can change the property of ion and electron charging on the electrode so it is sensitive to the plasma density which is controlled by the main power. The ion energy distribution was estimated by equivalent circuit model, being compared with the measured distribution obtained from the ion energy analyzer. Results show that the low frequency bias power changes effectively the low energy population of ion in the energy distribution.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.669-674
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• 1996

The theory of quantum mechanics states that for any system there are a set of discrete physical states, quantum states, which corresponds a particular energy level of the system. The lowest energy the system can have, corresponding to its ground state, is not necessarily zero, but depends only on the precise microscopic nature of the system under consideration. At the absolute zero of temperature all systems will be in their lowest energy state (zero point energy) and as the system is warmed from OK, the higher energy states become occupied. The probability of occupancy of the excited states relative to that of the ground state is proportional to the absolute temperature. Therefore we can obtain nuclear dipole and quadrupole moment very accurately at ultra low temperature (<15mk) by NMR and from the destruction of anisotropy. The former is called LTNO/NMR and the latter is called LTNO (Low Temperature Nuclear Orientation). In this paper we discuss and introduce only an experimental apparatus with results of cooling power test, a helium dilution refrigerator, which can reache 8mK, and an actual technique for the experiment, a theory and results will be presented in another papers.

• Nuclear Engineering and Technology
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• v.44 no.4
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• pp.429-436
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• 2012

Critical heat flux (CHF) is the thermal limit of a phenomenon in which a phase change occurs during heating (such as bubbles forming on a metal surface used to heat water), which suddenly decreases the heat transfer efficiency, thus causing localized overheating of the heating surface. The enhancement of CHF can increase the safety margins and allow operation at higher heat fluxes; thus, it can increase the economy. A very interesting characteristic of nanofluids is their ability to significantly enhance the CHF. Nanofluids are nanotechnology-based colloidal dispersions engineered through the stable suspension of nanoparticles. All experiments were performed in round tubes with an inner diameter of 0.01041 m and a length of 0.5 m under low pressure and low flow (LPLF) conditions at a fixed inlet temperature using water, 0.01 vol.% $Al_2O_3$/water nanofluid, and SiC/water nanofluid. It was found that the CHF of the nanofluids was enhanced and the CHF of the SiC/water nanofluid was more enhanced than that of the $Al_2O_3$/water nanofluid.

• 한국초전도학회:학술대회논문집
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• 2008.08a
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• pp.79-79
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• 2008

• 한국초전도학회:학술대회논문집
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• 2008.08a
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• pp.7-7
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• 2008

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.125-129
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• 1996

The energy response of HPGe detector for low energy Photons was determined by using three Monte Carlo codes. MCNP4A. EGS4, and CYLTRAN in ITS3. In this study. bare HPGe detector$(100 mm^2{\times}10mm)$ was used and a pencil beam was incident perpendicularly on the center of the detector surface. The photopeak efficiency, $K_{\alpha}$ and $K_{\beta}$ escape fractions were calculated as a function of incident X-ray energies ranging from 12 to 60 keV in 2-keV increments. Since the Compton. elastic. ana penetration fraction were negligible in this energy range. they were ignored in the calculation. Although MCNP. EGS, and CYLTRAN codes calculated slightly different energy response of HPGe detector for low energy Photons, it appears that the three Monte Carlo codes can Predict the low energy Photon scattering Processes accurately. The MCNP results, which are generally known as to be less accurate at low energy ranges than the EGS and ITS results. are comparable to the results of EGS and ITS and are applicable to the calculation of the low energy response data of a detector.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.5 no.1
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• pp.7-11
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• 2009

The purpose of this study is to investigate the performance of a water heat source cascade heat pump system R717(Ammonia) is used for a low-stage working fluid while R134a is for a high-stage. In order to gain a high temperature supply water in winter season, the system is designed to perform a cascade cycle. In this study, two experiments were carried out. One is a system starting test from the low load temperature of $10^{\circ}C$. The other is a system performance investigation over the R717 compressor capacity changes. Experimental results show that when it starts from the low load temperature, the suction temperature of the low-stage compressor is higher than that of a high-stage. The system performance increases when a water source temperature or a low-stage compressor rotational frequency goes higher.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.10
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• pp.80-87
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• 2006

Metallic sandwich plate with a truss core has metallic inner structures which have low relative density between a pair of metal skin sheets or face sheets. In this work, low impact tests have been carried out to examine the behavior of sandwich plates with a pyramidal truss core. For the low velocity impact, the impact apparatus of drop weight type has been fabricated. From the results of the experiments, maximum energy absorption is found to happen when the upper sheet fails. The sandwich plate loses its absorption ability as soon as the inner structures have been crashed completely and optimal core thickness has existed to maximize energy absorption. Comparing the metallic sandwich plate with the monocoque plate, the absorbed energy has been improved up to 160 % and the deflection decreased by up to 76%. As a result, the metallic sandwich plate with a truss core is shown to have good material for impact resistance and energy absorption.

• Journal of the Korean Society for Advanced Composite Structures
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• v.3 no.2
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• pp.36-46
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• 2012

Structure Insulated Panel (SIP) is an wooden structure material with which structure and insulation functions are satisfied. Hence, it would be a cost-effective model to implement low energy house which has higher insulation and structure performance and which the wall thickness is able to be reduced. In this study, performance of thermal insulation and fire resistance were evaluated in order to verify applicability to low energy house. Fire resistance test is performed on vertical load bearing members for partitions, and the test results satisfy one hour of fire resistance condition according to KS F 2257. The members include two layers of fireproof gypsum board with thicknesses of 12.5mm attached to SIP. Thermal insulation performance is satisfied with the 2012 standard ($0.225W/m^2{\cdot}K$). As the performance of resistance and thermal insulation are satisfied, SIP is expected to be applied to low energy building materials. In the future, the structural safety will be confirmed by structural performance and seismic performance test and the guidelines for distribution will be drawn up.