• Korean Journal of Soil Science and Fertilizer
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• v.49 no.3
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• pp.282-286
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• 2016

This study was carried out to evaluate the effect of application of urea and combination of urea and pig manure compost (PMC) on the occurrence of and the recovery from ammonium ($NH_4{^+}$) toxicity in Chinese cabbage. To identify $NH_4{^+}$ toxicity of the crop four levels of urea at 0, 160, 320, and $480kg\;N\;ha^{-1}$ were applied, in addition, three levels of PMC at 10, 20, and $40M/T\;ha^{-1}$ was also applied with urea $320kg\;ha^{-1}$. For recovery $NH_4{^+}$ toxicity, six levels of sucrose were treated at the amount of 0, 600, 1,200, 1,800, 2,400, and $3,000kg\;C\;ha^{-1}$ at each level of combining treatments of urea and PMC. Our results showed that $NH_4{^+}$ toxicity was occurred at every urea application of $320kg\;N\;ha^{-1}$ regardless of PMC applied to the soils because $NH_4{^+}$ contents in the soils were more than $155mg\;kg^{-1}$ which was found to be the critical level to damage crop growth at 2 days after transplanting (DAT) in this experiment, the more sucrose was applied up to $1,800kg\;C\;ha^{-1}$ for the plants damaged by ammonium toxicity occurred at $320kg\;N\;ha^{-1}$, the greater extents recover the plants from the toxicity. PMC showed the similar effect with sucrose on recovering Chinese cabbage plants from $NH_4{^+}$ toxicity at 30 DAT.

• Magazine of the Korea Concrete Institute
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• v.11 no.1
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• pp.255-266
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• 1999

The objective of this experiment is to observe the elastic and inelastic behaviors of high-rise reinforced concrete frames having non-seismic details. To do this, a building frame designed according to Korean seismic code and detailed in the Korean conventional practice was selected. A 1:12 scale plane frame model was manufactured according to similitude law. A reversed lateral load test and a monotonic pushover test were performed under the displacement control. To simulate the earthquake effects, the lateral force distribution was maintained to be an inverse triangle by using a whiffle tree. From the tests, base shears, crack pattern, local rotations in the ends of critical members and the relations between interstory drift versus story shear are obtained. Based on test results, conclusions are drawn on the implications of the elastic and inelastic behaviors of a high-rise reinforced concrete frame having non-seismic details.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.7
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• pp.695-701
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• 2013

The suppression of a thermocapillary flow (Marangoni flow) by a nonionic surfactant is experimentally investigated for evaporating pure water droplets on hydrophobic substrates. The experiment shows that as the initial concentration of the surfactant increases, the velocity and lifetime of the flow monotonically decrease. The result confirms the no-slip boundary condition at a liquid-air interface, which is explained on the basis of the previous model regarding the effect of surfactants on the no-slip condition. Interestingly, at an initial concentration much less than a critical value, it is found that depinning of the contact line occurs during the early stage of evaporation, which is ascribed to a reduction in the contact angle hysteresis owing to the presence of the Marangoni flow.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.384-388
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• 2003

Twenty yearling lambs of Southeast Nigeria dwarf, liveweight ($18{\pm}1.9 kg$) were grouped into 5 treatments. Dry brewer's grain was substituted for maize offal in the experiment diets namely A to E at 0%, 15%, 30%, 45% and 60% respectively, as supplement to low quality, dry season cassava leaf top and Andropogan gayanus hay at 1:1 ratio that lasted for 56 days. After which 5 of the lambs (average bodyweight=$24.3{\pm}1.5kg$) were transferred to metabolism crates to determine the digestibility and nitrogen/protein balance studies. While the mean group intakes were (945.9, 996.1, 1,040.5, 1,148.5 and 1,037.7 g conc. DM/day), the growth rates were (115.1, 124.1, 152.5, 168.5 and 123.1 g liveweight gain/day), respectively. There was a recorded decline in both intake (p>0.05) and growth rate (p<0.05) as the level of dry brewer's grain was increased beyond 45% of the supplement. Similar trend was observed on the protein and organic matter efficiency ratios (p>0.05) together with the organic matter intake. The urine nitrogen output was also significant (p>0.05). The work further revealed that, at a certain critical level of intake, dry brewer's grain is able to support growth rates measurable to or better than those noted when feeding maize offal to lambs, and went on to prove dry brewer's grain as an attractive supplementary feed for the drier months of the year, in the Southeast of Nigeria.

• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.415-419
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• 2018

This paper predicts and measures the C/N ratio of a beacon signal transmitted from geostationary orbit satellite KorSat 5A ($113^{\circ}E$) at a ground station located in Kimpo. Based on the ground stations, we compared the rain attenuation of the zone K of ITU-R and the rain attenuation which analyzed the domestic weather information. In ITU-R, the Korean rainfall characteristics are classified into zone K, but forecasting the rainfall intensity and attenuation of three adjacent cities based on the cumulative rainfall data per minute from 2013 to 2017. The calculation of rainfall path and attenuation is based on ITU-R recommendations. The change of the C/N according to the rainfall amount was confirmed through the 2 week satellite beacon signal C/N measurement. The predicted critical C/N was decreased to 12 dB at $A_{0.3}$. During the experiment, it was confirmed that it decreased up to 8 dB according to the concentrated rainfall.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.465-469
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• 2016

The usage of the correct combustion characteristic of the treated substance for the safety of the process is critical. For the safe handling of cumene being used in various ways in the chemical industry, the flash point and the autoignition temperature (AIT) of cumene was experimented. And, the lower explosion limit of cumene was calculated by using the lower flash point obtained in the experiment. The flash points of cumene by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $33^{\circ}C$, respectively. The flash points of cumene by using the Tag and Cleveland open cup testers are measured $43^{\circ}C$ and $45^{\circ}C$. The AIT of cumene by ASTM 659E tester was measured as $419^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• Journal of ILASS-Korea
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• v.20 no.1
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• pp.28-34
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• 2015

Recently, some researchers have been carried out risk assessment of vehicles exhaust on human health. Especially, some of VOCs which is non-controlled, was classified to hazardous pollutant, such as 1,3-Butadiene and BTEX(Benzene, Toluene, Ethylbenzene and Xylene). Therefore, the profile on non-controlled pollutant may be needed in the future, because it would be critical data or information to control them. Additionally, with increasing amount of motorcycle, the source profiling is essential for estimating emission factor and amount on motorcycle exhaust. For these, in this study, imported motorcycles (8 vehicles) were selected as a test model while considering the increasing ratio on sales volume between 2013 and 2014; it was also compared with domestic motorcycles on those. The experiment was conducted by driving mode, UDC and ECE+EUDC that made from EURO III. In addition, it was performed at cold start driving mode without effect by displacement, for evaluating only correlation of BTEX with HC. In order to apply the ratio (m,p-Xylene/o-Xylene) as a marker, the ratio was compared with those of tunnel, road side and residential area. As a result, it showed best correlation ($R^2=0.98$) among those. In the future, it has to be considered as a marker for effect evaluation to atmospheric environment by exhaust emission.

• Journal of KIISE:Software and Applications
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• v.32 no.5
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• pp.385-395
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• 2005

Long sentence analysis has been a critical problem in machine translation because of high complexity. The methods of intra-sentence segmentation have been proposed to reduce parsing complexity. This paper presents the intra-sentence segmentation method based on maximum entropy probability model to increase the coverage and accuracy of the segmentation. We construct the rules for choosing candidate segmentation positions by a teaming method using the lexical context of the words tagged as segmentation position. We also generate the model that gives probability value to each candidate segmentation positions. The lexical contexts are extracted from the corpus tagged with segmentation positions and are incorporated into the probability model. We construct training data using the sentences from Wall Street Journal and experiment the intra-sentence segmentation on the sentences from four different domains. The experiments show about $88\%$ accuracy and about $98\%$ coverage of the segmentation. Also, the proposed method results in parsing efficiency improvement by 4.8 times in speed and 3.6 times in space.

• Journal of Power Electronics
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• v.18 no.3
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• pp.841-852
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• 2018

This paper presents a dual-algorithm search method (GWO-GSO) combining grey wolf optimization (GWO) and golden-section optimization (GSO) to realize maximum power point tracking (MPPT) for photovoltaic (PV) systems. First, a modified grey wolf optimization (MGWO) is activated for the global search. In conventional GWO, wolf leaders possess the same impact on decision-making. In this paper, the decision weights of wolf leaders are automatically adjusted with hunting progression, which is conducive to accelerating hunting. At the later stage, the algorithm is switched to GSO for the local search, which play a critical role in avoiding unnecessary search and reducing the tracking time. Additionally, a novel restart judgment based on the quasi-slope of the power-voltage curve is introduced to enhance the reliability of MPPT systems. Simulation and experiment results demonstrate that the proposed algorithm can track the global maximum power point (MPP) swiftly and reliably with higher accuracy under various conditions.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.2
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• pp.145-153
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• 2009

This research utilized the manual to calculate the structural scale of stone and gabion, which was developed through comparison and verification of the results drawn by hydraulic model experiment and existing empirical formula. Appropriate structural scale of stone according to the construction site when the critical velocity was exceeded, utilizing the previously expected and recorded data on current velocity per day and per hour during the final closure period for Saemangeum sea dike. Also, the scale of rocks was presented, considering the altercation in water depth according to the construction. The developed manual offered appropriate rate of mixed use of stone and gabion that suits various flow velocities, which will minimize any loss of stone-gabion and contribute to successful final closure, and proved the utility and application of the manual.