• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.378-378
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• 2010

The ZnSe epilayers were grown on the GaAs substrate by hot wall epitaxy. After the ZnSe epilayers treated in the vacuum-, Zn-, and Se-atmosphere, respectively, the defects of the epilayer were investigated by means of the low, temperature photoluminescence measurement. The dominant peaks at 2.7988 eV and 2.7937 eV obtained from the PL spectrum of the as-grown ZnSe epilayer were found to be consistent with the upper and the lower polariton peak of the exciton, $I_2$ ($D^{\circ}$, X), bounded to the neutral donor associated with the Se-vacancy. This donor-impurity binding energy was calculated to be 25.3 meV. The exciton peak, $I_l^d$, at 2.7812 eV was confirmed to be bound to the neutral acceptor corresponded with the Zn-vacancy.

• 한국연초학회지
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• 제7권1호
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• pp.25-31
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• 1985

For shortening the tobacco breeding cycle, seedlings with 6, 8 and II leaves of 2 flue.cured tobacco varieties, day. neutral type and photoperiod-sensitive type, were grown in controlled-environment room (CER), programmed for temperature of $18^{\circ}C$ and 8.hour day period of 30 klux, for 20, 30 and 40 days. All of plants of day.neutral type variety treated in CER, regardless of seedling stage and duration, flowered earlier than the untreated plants. In the 6.leaf seedlings stage of photoperiod-sensitive type variety, plants treated for 20 and 30 days in CER did not accelerate the flowering. the tobacco plants, treated with low temperature for 20 days at 8.leaf seedling stage, flowered earlier in comparison with. the other treatment.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.299-302
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• 2008

The behavior of continuous welded rail tracks is directly affected by the following various parameters: rail size; track curvature; neutral temperature; misalignment; and ballast resistance. Most of these parameters are having the nature of random variables. Therefore, uncertainties exist in the buckling safety assessments. The evaluation of the buckling safety and the maintenance strategy based on the deterministic analysis are very inefficient since the value of deterministic parameters are selected in worst track condition. In this study, the probabilistic approach method were investigated considering the probabilistic distribution of major parameters such as the neutral temperature of rail and the ballast resistance.

• Wind and Structures
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• 제4권6호
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• pp.469-480
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• 2001

The Leipzig Wind Profile is generally known as a typical neutral planetary boundary layer flow. But it became clear from the present research that it was not completely neutral but weakly stable. We examined whether we could simulate the Leipzig Wind Profile by using a ($k-{\varepsilon}$) turbulence model including the equation of potential temperature. By solving analytically the Second Moment Closure Model under the assumption of local equilibrium and under the condition of a stratified flow, we expressed the turbulent diffusion coefficients (both momentum and thermal) as functions of flux Richardson number. Our ($k-{\varepsilon}$) turbulence model which included the equation of potential temperature and the turbulent diffusion coefficients varying with flux Richardson number reproduced the Leipzig Wind Profile.

• 천문학회보
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• 제44권2호
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• pp.78.3-78.3
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• 2019

We develop a novel technique that can constrain the evolutionary track of the epoch of reionization (EoR) by applying the convolutional neural network (CNN) to the 21-cm differential brightness temperature. We use 21cmFAST, a fast semi-numerical cosmological 21-cm signal simulator, to produce mock 21-cm map between z=6-13. We design a CNN architecture that predicts the volume-averaged neutral hydrogen fraction from the given 21-cm map. The estimated neutral fraction has a good agreement with its truth value even after smoothing the 21-cm map with somewhat realistic choices of beam size and the frequency bandwidth of the Square Kilometre Array (SKA). Our technique could be further utilized to denoise the 21-cm map or constrain the properties of the radiation sources.

• 천문학회보
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• 제45권1호
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• pp.66.2-66.2
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• 2020

We propose a deep learning analysis technique with a convolutional neural network (CNN) to predict the evolutionary track of the Epoch of Reionization (EoR) from the 21-cm differential brightness temperature tomography images. We use 21cmFAST, a fast semi-numerical cosmological 21-cm signal simulator, to produce mock 21-cm maps between z = 6 ~ 13. We then apply two observational effects, such as instrumental noise and limit of (spatial and depth) resolution somewhat suitable for realistic choices of the Square Kilometre Array (SKA), into the 21-cm maps. We design our deep learning model with CNN to predict the sliced-averaged neutral hydrogen fraction from the given 21-cm map. The estimated neutral fraction from our CNN model has great agreement with the true value even after coarsely smoothing with broad beam size and frequency bandwidth and heavily covered by noise with narrow beam size and frequency bandwidth. Our results show that the deep learning analyzing method has the potential to reconstruct the EoR history efficiently from the 21-cm tomography surveys in future.

• 한국조리학회지
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• 제3권
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• pp.259-270
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• 1997

The experiment was carried out to investigate the change of pH, total lipid, neutral lipid and phospholipid of pork portions which are picnic shoulder, loin, ham, boston butt and bacon belly during storage at 4$^{\circ}C$ weeks. The results obtained were as follows, 1. pH of butt, ham, bacon, picnic and loin stored at 4$^{\circ}C$ for 2 days were 6.3, 5.9, 5.8, 5.6 and 5.2 respectively. And then pH of pork portions increased gradually during storage period. 2. Total lipid content of the pork portions were 2.13% in ham, 2.78% in loin 4.55% in picnic, 5.74% in butt and 7.11% in bacon. During storage period, total lipid content decreased slightly. 3. In case of neutral lipid, the content in bacon, butt, picnic, loin and ham were 6.68%, 5.32%, 4.22%, 2.53%, and 1.88% respectively. During storage period, neutral lipid content decreased slightly. 4. Phospholipid content showed little differences among the portions. And then phospholipid content decreased significantly during storage period.

• 한국초전도ㆍ저온공학회논문지
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• 제15권4호
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• pp.34-38
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• 2013

According to the increase of electric consumption nowadays, power system becomes complicated. Due to this, the size of single line-to-ground fault from power system also increases to have many problems. In order to resolve these problems effectively, an Superconducting Fault Current Limiter(SFCL) was proposed and continuous study has been done. In this paper, an SFCL was combined to the neutral line of a transformer. An superconductivity has the characteristics of zero resistance below critical temperature. because of this, SFCL has nearly zero resistance. so we connecting SFCL to neutral line will not only have any loss in the normal operation but also have the less burden of electric power because of only limiting the initial fault current. We analyzed the characteristics of current, voltage according to the changes of turn ratio of 3 phase system in case of combinations of an SFCL to the neutral line. It was confirmed that the limiting rate of initial fault current by the increase of turn ratio was reduced.

• Asian-Australasian Journal of Animal Sciences
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• 제14권10호
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• pp.1400-1404
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• 2001

$Holstein\;{\times}\;indigenous$ multiparous dairy cows were offered diets with increasing roughage neutral detergent fiber (NDF) contents to determine the effects on intake, milk yield and compositions. Roughage NDF contents were 15, 18, 21 and 24% dry matter (DM), and concentrate NDF content was 10% DM. Experimental treatments were isonitrogenous and isocaloric diets. Maximum and minimum temperature humidity index during the experimental period were 85.9 and 76, respectively. Intakes of DM, crude protein and net energy, 4% fat corrected milk, milk protein and average daily gain decreased with increasing roughage NDF contents (p<0.05). Intakes of ether extract (p<0.01) and dietary NDF (p>0.05) and milk fat (p<0.01) increased with increasing roughage NDF contents. The results support the conclusion that higher DM intake, optimal milk yield and compositions can be maintained with lower roughage NDF diets for dairy cows under tropical conditions.

• 설비공학논문집
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• 제2권4호
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• pp.268-278
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• 1990

Hydrodynamic stability equations are formulated for natural convection flows adjacent to a heated or cooled, inclined, isothermal surface in pure water at $4^{\circ}C$, where the density variation with temperature becomes nonlinear. The resulting stability equations, when reduced to ordinary differential equations by a similarity transformation, constitute a two-point boundary-value problem, which was solved numerically. It is found from the obtained stability results that the neutral stability curves are systematically shifted to have lower critical Grashof numbers, as the inclination angle of upward-facing plate increases. Also, the nose of the neutral stability curve becomes blunter as the angle increases. It implies that the greater the inclination of the upward-facing plate, the more susceptible of the flow to instability for the wide range of disturbance wave number and frequency.